52 results on '"Xiao-Yuan Li"'
Search Results
2. Laboratory assessment of capillary rising in cement- and lime-treated engineered loess
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Sheng-Lin Wang, Xiao-Yuan Li, and Shunde Yin
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General Environmental Science ,Civil and Structural Engineering - Abstract
The capillary rising is one of the most common phenomena in fine-grained soils. However, research is limited for capillary actions in cementitiously treated engineered soils. In this study, a soil column test was performed for the free capillary rising in compacted loess and modified loess samples. Moisture content of compacted soil samples was measured and analyzed to determine capillary height and rising rate. Results indicated that there was a considerable capillary rising in loess and lime-modified loess, while the capillary rising in cement-treated loess was significantly restrained. Current models are not appropriate for the rate and height predictions of capillary rising in cementitiously treated loess, especially in early ages. Therefore, a logarithmic form correlation was suggested and validated. In addition, salt migration effect and microscopic properties of soils after capillary rising were evaluated. Overall, the paper presented an experimental study and prediction on the capillary rising behavior of treated and recompacted engineered loess.
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- 2022
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3. M1 acetylcholine receptors in somatostatin interneurons contribute to GABAergic and glutamatergic plasticity in the mPFC and antidepressant-like responses
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Manoela V. Fogaça, Min Wu, Chan Li, Xiao-Yuan Li, Ronald S. Duman, and Marina R. Picciotto
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Pharmacology ,Psychiatry and Mental health - Published
- 2023
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4. Mechanisms of the Ping-wei-san plus herbal decoction against Parkinson’s disease: Multiomics analyses
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Ding Li, Hong-juan You, Guo-jie Hu, Ru-yong Yao, An-mu Xie, and Xiao-yuan Li
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Nutrition and Dietetics ,Endocrinology, Diabetes and Metabolism ,Food Science - Abstract
IntroductionParkinson’s disease is a neurodegenerative disorder involving loss of dopaminergic neurons. Multiple studies implicate the microbiota-gut-brain axis in Parkinson’s disease pathophysiology. Ping-wei-san plus Herbal Decoction, a traditional Chinese medicine composition with beneficial effects in Parkinson’s disease, may have a complex array of actions. Here we sought to determine whether gut microbiota and metabolic pathways are involved in Ping-wei-san plus herbal therapy for Parkinson’s disease and to identify functional pathways to guide research.Methods and resultsThe model of Parkinson’s disease were induced with the rotenone. The Ping-wei-san plus group received the PWP herbal decoction for 90 days, after which all groups were analyzed experimentally. PWP herbal treatment improved motor behavior and emotional performance, balanced gut microbiota, and benefited dietary metabolism. Tandem Mass Tags mass spectrometry identified many differentially expressed proteins (DEPs) in the substantia nigra and duodenum in the PWP group, and these DEPs were enriched in pathways such as those involving cAMP signaling, glutamatergic synapses, dopaminergic synapses, and ribosome-rich functions in the gut. The PWP group showed increases in recombinant tissue inhibitors of metalloproteinase 3, and nucleotide-binding oligomerization domain, leucine rich repeat, and pyrin domain containing proteins 6 in the substantia nigra and decreased parkin, gasdermin D, recombinant tissue inhibitors of metalloproteinase 3, and nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing proteins 6 in the duodenum.DiscussionIn conclusion, this study combined gut microbiota, metabolomics, and proteomics to evaluate the mechanism of action of Ping-wei-san plus on Parkinson’s disease and revealed that PWP herbal treatment modulated gut microbiota, altered metabolite biological pathways, and affected functional pathway protein expression in Parkinson’s disease mice, resulting in therapeutic effects.
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- 2023
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5. The Research on the Treatment of Metastatic Skin Cutaneous Melanoma by Huanglian Jiedu Decoction Based on the Analysis of Immune Infiltration Analysis
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Shi-Fang Li, Tian-Yue Sun, Xiao-Wei Sun, Guo-Jie Hu, Ding Li, and Xiao-Yuan Li
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0303 health sciences ,Article Subject ,business.industry ,Decoction ,Geo database ,medicine.disease ,Huanglian jiedu ,Metastasis ,Other systems of medicine ,03 medical and health sciences ,0302 clinical medicine ,Complementary and alternative medicine ,Immune infiltration ,030220 oncology & carcinogenesis ,Cutaneous melanoma ,Cancer research ,medicine ,Signal transduction ,business ,Immune cell infiltration ,RZ201-999 ,Research Article ,030304 developmental biology - Abstract
Objective. To explore the potential mechanism of Huanglian Jiedu Decoction (HJD) treatment and prevention of metastatic Cutaneous Melanoma (CM) occurrence and metastasis based on network pharmacological methods and immune infiltration analysis. Methods. The GEO database was used to obtain metastatic CM disease targets, the TCMSP database and the HERB database were used to obtain HJD action targets, core genes were screened by protein interaction network, and the potential mechanism of HJD in the treatment of metastatic CM was explored by enrichment analysis, prognostic analysis and immune infiltration analysis. Results. HJD treatment of metastatic CM involved 60 targets, enrichment analysis showed that HJD treatment of metastatic CM involved Chemokine signaling pathway, NF-kappa B signaling pathway, and Fluid shear stress and atherosclerosis, etc. Prognostic analysis revealed that HJD had a certain ability to improve the prognosis of metastatic CM patients. Immune infiltration analysis showed that HJD could inhibit the immune cell infiltration of metastatic CM patients by acting on related targets. Conclusions. Our study identified the potential mechanism of HJD in the treatment of metastatic CM through network pharmacology, and revealed the mechanism of HJD in the prevention of Skin Cutaneous Melanoma metastasis through immune infiltration analysis and prognostic analysis.
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- 2021
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6. [Pharmacokinetics of eight active ingredients of Salviae Miltiorrhizae Radix et Rhizoma-Puerariae Lobatae Radix combination in rats]
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Xiao-Yan, Liu, Xiao-Yuan, Li, Xu, Chen, Zhi-Fang, Huang, Yun-Hua, Liu, Yu-Hong, Liu, Yan, Chen, Zheng-Huai, Tan, and Jin-Hai, Yi
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Pueraria ,Tandem Mass Spectrometry ,Animals ,Salvia miltiorrhiza ,Plant Roots ,Chromatography, High Pressure Liquid ,Rhizome ,Drugs, Chinese Herbal ,Rats - Abstract
To reveal the rationality of compatibility of Salviae Miltiorrhizae Radix et Rhizoma(SMRR) and Puerariae Lobatae Radix(PLR) from the perspective of pharmacokinetics, this study established a UPLC-MS/MS method for quantitative determination of PLR flavonoids(3'-hydroxy puerarin, puerarin, puerarin 6″-O-xyloside, 3'-methoxy puerarin, puerarin apioside) and salvianolic acids and tanshinones(salvianolic acid B, cryptotanshinone, and tanshinone Ⅱ_A) in plasma of rats. Rats were given SMRR extract, PLR extract, and SMRR-PLR extract by gavage and then plasma was collected at different time. UPLC separation was performed under the following conditions: Eclipse C_(18) column(2.1 mm×50 mm, 1.8 μm), 0.1% formic acid in water(A)-0.1% formic acid in acetonitrile(B) as mobile phase for gradient elution. Conditions for MS are as below: multiple reaction monitoring(MRM), ESI~(+/-). Comprehensive validation of the UPLC-MS/MS method(specifically, from the aspects of calibration curve, precision, accuracy, repeatability, stability, matrix effect, extract recovery) was performed and the result demonstrated that it complied with quantitative analysis requirements for biological samples. Compared with SMRR extract alone or PLR extract alone, SMRR-PLR extract significantly increased the AUC and C_(max) of PLR flavonoids and tanshinones in rat plasma, suggesting that the combination of SMRR and PLR promoted the absorption of the above components. The underlying mechanism needs to be further studied.
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- 2022
7. Efficacy and Safety of Anlotinib Combined with PD-1 Blockades for Patients with Previously Treated Epithelial Ovarian Cancer: A Retrospective Study
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Xiao-Yuan Li, Yang Rao, Bing Sun, and Xue-Mei Mao
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International Journal of General Medicine ,General Medicine - Abstract
Xiao-Yuan Li,1,* Yang Rao,2,* Bing Sun,3 Xue-Mei Mao4 1Department of Medical Oncology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, Peopleâs Republic of China; 2Department of Gynecological Oncology, Tianjin Central Obstetrics and Gynecology Hospital, Tianjin, 300199, Peopleâs Republic of China; 3Department of Radiation Oncology, The Fifth Medical Center, Chinese PLA General Hospital, Beijing, 100071, Peopleâs Republic of China; 4Department of Obstetrics and Gynecology, Tianjin Integrated Traditional Chinese and Western Medicine Hospital (Nankai Hospital), Tianjin, 300102, Peopleâs Republic of China*These authors contributed equally to this workCorrespondence: Xue-Mei Mao; Bing Sun, Tel +86 13820312420 ; +86 13810193881, Email mxm0206@163.com; sunice116@163.comPurpose: This study was to investigate the efficacy and safety of anlotinib combined with programmed cell death protein 1 (PD-1) blockades for patients with previously treated advanced epithelial ovarian cancer (EOC).Patients and Methods: Present study was designed as a retrospective study, a total of 32 patients with advanced EOC who progressed after at least two lines previously available standard therapy were included in this study. All the patients were administered with anlotinib combined with PD-1 blockades administration. Clinical activity was implemented and analyzed, which was assessed according to the change of target lesion by imaging evidence and all the subjects were followed up regularly. Safety profile were collected and documented during the treatment. Univariate analysis was carried out using log rank test and multivariate analysis were adjusted by Cox regression analysis.Results: The best overall response suggested that partial response was noted in 12 patients, stable disease was observed in 14 patients, progressive disease was found in 6 patients. Therefore, the objective response rate (ORR) of the 32 patients was 37.5% (95% CI: 21.1â 56.3%), disease control rate (DCR) of the patients was 81.3% (95% CI: 63.6â 92.8%). The median follow-up duration of this study was 17.5 months (follow-up range: 0.9â 33.5 months). And the median PFS and OS of the 32-patient cohort was 6.8 months (95% CI: 2.64â 10.96) and 18.5 months (95% CI: 14.08â 22.92), respectively. The most common treatment-related adverse reactions were fatigue (68.8%), nausea and vomiting (56.3%), hypertension (50.0%) and diarrhea (40.6%). Multivariate Cox regression analysis for PFS indicated that ECOG performance status and FIGO stage were independent factors to predict PFS of patients with previously treated EOC.Conclusion: Anlotinib combined with PD-1 blockades demonstrated promising efficacy and tolerable safety profile for patients with previously treated advanced EOC preliminarily. The conclusion should be confirmed in more patients with advanced EOC subsequently.Keywords: epithelial ovarian cancer, anlotinib, PD-1 blockade, efficacy, safety
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- 2021
8. Adaptive Interference Simulation of Environment Noise
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Chun Xia Meng, Xiao Yuan Li, and Liang Zhang
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Physics ,Noise ,Interference (communication) ,Computer Science::Sound ,Frequency band ,Acoustics ,Speed of sound ,Ambient noise level ,Underwater acoustics ,Sonar ,Signal - Abstract
The sonar equation satisfied by the acoustic signal of the moving sound source is derived in the presence of artificial interference noise. Then, under the typical sound velocity conditions of shallow sea, considering the sound absorption of seawater, the propagation loss value of each frequency in the frequency band of 20–40 kHz is calculated, and the noise intensity of the marine environment is quantitatively analyzed from the sonar equation according to the speed of sound source motion. Change over time. Finally, in different time periods, the simulation generates artificial intervention noise. The spectrum of this noise satisfies the spectral statistical characteristics of the measured ambient noise, and its intensity enables the sonar equation to be established all the time. The simulation results show that when using the transducer to transmit human intervention noise, we can change the ocean environment noise level and significantly reduce the acoustic performance of the moving sound source.
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- 2021
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9. Efficacy of Shenling Baizhu San on stable chronic obstructive pulmonary disease patients: A systematic review and meta-analysis
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Qingyan Meng, Guo-Jie Hu, Mao Yuquan, Hui Liu, Tingting Zhang, Xin Du, Zhou Jie, Chunhong Wang, Xiao-Wei Sun, and Xiao-Yuan Li
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medicine.medical_specialty ,Walk Test ,law.invention ,Pulmonary function testing ,03 medical and health sciences ,FEV1/FVC ratio ,Pulmonary Disease, Chronic Obstructive ,0302 clinical medicine ,Randomized controlled trial ,law ,Internal medicine ,Forced Expiratory Volume ,Drug Discovery ,Medicine ,Humans ,030304 developmental biology ,Pharmacology ,0303 health sciences ,COPD ,Clinical Trials as Topic ,business.industry ,Maximal Voluntary Ventilation ,Odds ratio ,Publication bias ,medicine.disease ,Databases, Bibliographic ,respiratory tract diseases ,Respiratory Function Tests ,Clinical trial ,Treatment Outcome ,030220 oncology & carcinogenesis ,Meta-analysis ,Quality of Life ,business ,Drugs, Chinese Herbal - Abstract
Ethnopharmacological relevance Shenling Baizhu San (SBS) as a classic Chinese medicine prescription, has been extensively used in gastrointestinal diseases, such as ulcerative colitis and chronic diarrhea. In recent years, SBS has shown a beneficial effect on chronic obstructive pulmonary disease (COPD) patients. However, clinical trials had shown conflicting results of SBS on improving pulmonary function and other related indicators of patients with stable COPD. The efficacy of SBS on stable COPD patients has not been fully assessed. Aim of the study To determine whether the SBS used in the treatment of gastrointestinal disease was effective to treat COPD, we assessed the clinical evidence and efficacy of SBS supplemental treatment on stable COPD patients by a systematic review and meta-analysis of clinical trials. Materials and methods Nine electronic databases were searched to include clinical trials (published until August 31, 2020) with SBS as a supplementation treatment on stable COPD. Mean difference (MD) was used to evaluate continuous variables, odds ratio (OR) was calculated to evaluate dichotomous. The Egger's test was applied for publication bias. Results A total of 770 COPD participants from 11 trials that met the inclusion criteria were included. The meta-analysis showed that modified SBS could improve the exercise endurance, life quality scores of stable COPD patients, and also showed the potential benefits to pulmonary function of COPD patients than original SBS. Conclusion The methodological quality of included trials may limit the conclusions that indicate that modified SBS may have a promising treatment for improving FEV1/FVC and MVV, increasing exercise endurance and life quality scores on stable COPD patients.
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- 2020
10. Exploring the Effects of Changping Decoction on Irritable Bowel Syndrome by Pathway and Pharmacology Network Bioinformatics Analysis
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Xiao-Wei Sun, Guo-Jie Hu, Shi-Fang Li, Ding Li, Xiao-Yuan Li, and Tian-Yue Sun
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Bioinformatics analysis ,business.industry ,education ,Medicine ,Decoction ,business ,Bioinformatics ,medicine.disease ,Irritable bowel syndrome - Abstract
Background An increasing body of research has confirmed the effectiveness of Traditional Chinese Medicine (TCM) for the treatment of irritable bowel syndrome (IBS).Methods We explored the potential mechanism of Changping decoction (CPD) in the treatment of IBS through pathway analysis based on a network pharmacology approach. Public databases, including the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform, Gene Expression Omnibus, and STRING, were used to screen the active ingredients and targets of CPD. Enrichment analysis was performed using the R-3.6.0 software to expound the biological functions and related pathways of CPD targets. The Cytoscape software was used to construct a “disease-CPD-target” network and identify hub genes of CPD relevant for the treatment of IBS. Employing rat models, pathological observation and abdominal withdrawal reflex tests were used to verify the effectiveness of CPD in the treatment of IBS. Immunohistochemistry was used to confirm the relationship between the CPD treatment and hub genes.Results Network pharmacological analysis of CPD for the treatment of IBS identified 159 active ingredients. A total of 118 key targets were identified, including MAPK8, VEGFA, PTGS2, and others. A series of signaling pathways, such as MAPK, Kaposi sarcoma-associated herpesvirus infection, and IL-17 signaling pathway were found to play an important role in the therapeutic mechanism of CPD in the treatment of IBS. Pathological observation and abdominal withdrawal reflex tests confirmed that the symptoms of IBS in rats were relieved by CPD. Moreover, immunohistochemistry confirmed that CPD could inhibit the expression of inflammation-associated factors, such as VEGFA, MAPK8, and PTGS2.Conclusions Based on network pharmacology analysis, the present study provides insights into the potential mechanism of CPD in the treatment of IBS after successfully screening for associated key target genes and signaling pathways. These findings establish a theoretical basis for the development of CPD-derived therapeutics.
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- 2020
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11. Microbiota dysbiosis in honeybee (
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Man-Hong, Ye, Shu-Hang, Fan, Xiao-Yuan, Li, Islam Mohd, Tarequl, Chun-Xiang, Yan, Wan-Hong, Wei, Sheng-Mei, Yang, and Bin, Zhou
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Ecology, Conservation, and Global Change Biology ,fungi ,chalkbrood disease ,agrochemical exposure ,bacterial and fungal compositions ,honeybee ,American foulbrood disease ,Research Article - Abstract
American foulbrood (AFB) disease and chalkbrood disease (CBD) are important bacterial and fungal diseases, respectively, that affect honeybee broods. Exposure to agrochemicals is an abiotic stressor that potentially weakens honeybee colonies. Gut microflora alterations in adult honeybees associated with these biotic and abiotic factors have been investigated. However, microbial compositions in AFB- and CBD-infected larvae and the profile of whole-body microbiota in foraging bees exposed to agrochemicals have not been fully studied. In this study, bacterial and fungal communities in healthy and diseased (AFB/CBD) honeybee larvae were characterized by amplicon sequencing of bacterial 16S rRNA gene and fungal internal transcribed spacer1 region, respectively. The bacterial and fungal communities in disordered foraging bees poisoned by agrochemicals were analysed. Our results revealed that healthy larvae were significantly enriched in bacterial genera Lactobacillus and Stenotrophomonas and the fungal genera Alternaria and Aspergillus. The enrichment of these microorganisms, which had antagonistic activities against the etiologic agents for AFB and CBD, respectively, may protect larvae from potential infection. In disordered foraging bees, the relative abundance of bacterial genus Gilliamella and fungal species Cystofilobasidium macerans were significantly reduced, which may compromise hosts' capacities in nutrient absorption and immune defence against pathogens. Significantly higher frequency of environmentally derived fungi was observed in disordered foraging bees, which reflected the perturbed microbiota communities of hosts. Results from PICRUSt and FUNGuild analyses revealed significant differences in gene clusters of bacterial communities and fungal function profiles. Overall, results of this study provide references for the composition and function of microbial communities in AFB- and CBD-infected honeybee larvae and foraging bees exposed to agrochemicals.
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- 2020
12. Reconstruction and Evaluation of Ship Radiated Noise Signal in Ocean Channel
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Chun Yan Xia, Xiao Yuan Li, and Chun Xia Meng
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Physics ,Noise measurement ,Noise (signal processing) ,Acoustics ,Continuous spectrum ,Probability density function ,Time domain ,White noise ,Signal ,Time–frequency analysis - Abstract
Ship radiated noise can generally be regarded as a random process that undergoes steady states, but the complexity of its generation mechanism makes its spectral characteristics different from white noise signals. Realistic simulation of the time domain signal of ship radiated noise can improve performance of acoustic equipment. In this paper, the analysis methods of the ship's radiation noise line spectrum and continuous spectrum characteristics are studied. The near-field radiation noise data of a certain type of ship under the same operating conditions is analyzed in the time-frequency domain, and the statistically significant radiation noise spectrum characteristics are obtained. The probability density function is used to generate random numbers that meet this statistical characteristic to describe the frequency spectrum of underwater radiating sound sources at various frequencies, and the Fourier synthesis method is used to reconstruct the time-domain pass characteristic of the ship's radiated noise signal under arbitrary sound velocity conditions in shallow water. Finally, the evaluation method of the radiated noise signal modeling results is studied, and the reconstructed signal is evaluated by the similarity calculation between the measured and simulated signal. The results show that the reconstructed time domain signal has higher fidelity.
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- 2020
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13. Modeling of High Frequency Sound Propagation Characteristics in Shallow Sea
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Liang Zhang, Xiao Yuan Li, and Chun Xia Meng
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Waves and shallow water ,Computer Science::Sound ,Acoustics ,Vertical direction ,Reflection (physics) ,Calibration ,Refraction (sound) ,Seawater ,Signal ,Geology ,Radio spectrum - Abstract
10kHz~38kHz High frequency sound signal is common signal form of marine acoustic equipment, when the high frequency acoustic signal propagates in seawater, it not only produces reflection and refraction on the seawater interface, but also is obviously affected by the sound absorption of seawater. In order to obtain the law of high frequency sound propagation in shallow sea, this paper uses several self-condenser hydrophones and depth sensors placed vertically at equal intervals as receiving device, fixed point high frequency sound propagation experiments with different frequency and frequency bands were carried out in a shallow sea in China. Then setting the acoustic parameters of the ocean guide and the acoustic absorption coefficient of the sea water at various frequencies, A high frequency near-field acoustic propagation model in shallow water is established by using ray acoustics. Finally, the measured sound propagation loss in the vertical direction of seawater is compared with the propagation loss predicted by the model. The analysis results show that different frequencies and frequency bands, at different horizontal distances, the measured propagation loss values are in good agreement with the theoretical values, and the sound propagation model established in this paper can accurately describe the high frequency sound propagation characteristics of the sea area. The research method in this paper is of great significance for the offshore calibration and performance prediction of high frequency marine acoustic equipment under shallow sea conditions.
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- 2020
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14. Distinct downstream targets of the medial prefrontal cortex underlie discrete antidepressant responses to ketamine
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Ryota Shinohara, Brendan D. Hare, Rong-Jian Liu, Jin Hua Li, Xiao-Yuan Li, Catharine H. Duman, Ralph J. DiLeone, and Ronald S. Duman
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Applied Mathematics ,General Mathematics - Published
- 2022
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15. Medial PFC AMPA receptor and BDNF signaling are required for the rapid and sustained antidepressant-like effects of 5-HT
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Kenichi, Fukumoto, Manoela V, Fogaça, Rong-Jian, Liu, Catharine H, Duman, Xiao-Yuan, Li, Shigeyuki, Chaki, and Ronald S, Duman
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Depressive Disorder, Major ,Depression ,musculoskeletal, neural, and ocular physiology ,Brain-Derived Neurotrophic Factor ,Prefrontal Cortex ,Antidepressive Agents ,Article ,Mice ,nervous system ,Receptor, Serotonin, 5-HT1A ,Animals ,Humans ,Female ,Receptors, AMPA - Abstract
We previously reported that the serotonergic system is important for the antidepressant-like effects of ketamine, a non-competitive N-methyl-D-aspartate receptor antagonist, which produces rapid and long-lasting antidepressant effects in patients with major depressive disorder (MDD). In particular, selective stimulation of the 5-HT(1A) receptor in the medial prefrontal cortex (mPFC), as opposed to the somatic 5-HT(1A) autoreceptor, has been shown to play a critical role in the antidepressant-like actions of ketamine. However, the detailed mechanisms underlying mPFC 5-HT(1A) receptor-mediated antidepressant-like effects are not fully understood. Here we examined the involvement of the glutamate AMPA receptor and brain-derived neurotrophic factor (BDNF) in the antidepressant-like effects of 5-HT(1A) receptor activation in the mPFC. The results show that intra-mPFC infusion of the 5-HT(1A) receptor agonist 8-OH-DPAT induces rapid and long-lasting antidepressant-like effects in the forced swim, novelty-suppressed feeding, female urine sniffing, and chronic unpredictable stress tests. In addition, the results demonstrate that the antidepressant-like effects of intra-mPFC infusion of 8-OH-DPAT are blocked by co-infusion of an AMPA receptor antagonist or an anti-BDNF neutralizing antibody. In addition, mPFC infusion of 8-OH-DPAT increased the phosphorylation of signaling proteins downstream of BDNF, including mTOR, ERK, 4EBP1, and p70S6K. Finally, selective stimulation of the 5-HT(1A) receptor increased levels of synaptic proteins and synaptic function in the mPFC. Collectively, these results indicate that selective stimulation of 5-HT(1A) receptor in the mPFC exerts rapid and sustained antidepressant-like effects via activation of AMPA receptor/BDNF/mTOR signaling in mice, which subsequently increase synaptic function in the mPFC, and provide evidence for the 5-HT(1A) receptor as a target for the treatment of MDD.
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- 2019
16. Apatinib in the treatment of advanced non-small-cell lung cancer: A meta-analysis
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Guocan Yu, Bo Ye, Xiao-Yuan Li, Guan-Rong Zheng, Jun Yang, and Li-Liang Xu
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Oncology ,medicine.medical_specialty ,Lung Neoplasms ,Pyridines ,Antineoplastic Agents ,02 engineering and technology ,law.invention ,chemistry.chemical_compound ,Randomized controlled trial ,law ,Internal medicine ,Carcinoma, Non-Small-Cell Lung ,0502 economics and business ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Odds Ratio ,Humans ,Apatinib ,Lung cancer ,Proportional Hazards Models ,Randomized Controlled Trials as Topic ,business.industry ,Applied Mathematics ,05 social sciences ,Hazard ratio ,General Medicine ,Odds ratio ,medicine.disease ,Confidence interval ,Progression-Free Survival ,Computational Mathematics ,Treatment Outcome ,chemistry ,Modeling and Simulation ,Meta-analysis ,Relative risk ,020201 artificial intelligence & image processing ,General Agricultural and Biological Sciences ,business ,050203 business & management - Abstract
Objectives: The purpose of this meta-analysis was to evaluate the efficacy and toxicity profile of apatinib for the treatment of advanced non-small cell lung cancer (NSCLC). Methods: We systematically searched databases for randomized clinical trials published as of November 25, 2017, in which apatinib treatment was compared to placebo or chemotherapy in patients with advanced NSCLC. Two investigators independently assessed the articles and extracted their data. The hazard ratios (HRs) for progression-free survival (PFS), relative risks (RRs) for overall response rates (ORRs), disease control rates (DCRs), and odds ratios (ORs) for main toxicity were analyzed using the RevMan 5.3 software (Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014). Results: Our analysis included 413 patients from 5 clinical studies. The pooled HR for PFS was 0.32 (95% confidence interval (CI) 0.21-0.48; P < 0.00001). The pooled RRs for ORR and DCR were 2.03 (95% CI 1.36-3.01; P = 0.0005) and 1.66 (95% CI 1.07-2.57; P = 0.02), respectively. The pooled OR for main toxicity was 1.34 (95% CI, 0.57-3.17; P = 0.5). Conclusions: Apatinib was a viable treatment alternative for advanced NSCLC, as it offered a clinically meaningful and statistically significant improvement in PFS, ORR, and DCR. Moreover, therapy with apatinib did not significantly increase toxicity.
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- 2019
17. Heavy-ion and pulsed-laser single event effects in 130-nm CMOS-based thin/thick gate oxide anti-fuse PROMs
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Bing Ye, Zhang Zhangang, Peixiong Zhao, Xiao-Yuan Li, Chao Geng, Tianqi Liu, Jie Liu, Qing-Gang Ji, Chang Cai, Dongqing Li, and Li-Hua Mo
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Nuclear and High Energy Physics ,Materials science ,010308 nuclear & particles physics ,business.industry ,Linear energy transfer ,Integrated circuit ,01 natural sciences ,Upset ,law.invention ,Nuclear Energy and Engineering ,CMOS ,Gate oxide ,Single event upset ,law ,0103 physical sciences ,Optoelectronics ,010306 general physics ,business ,Radiation hardening ,Electronic circuit - Abstract
Single event effects of 1-T structure programmable read-only memory (PROM) devices fabricated with a 130-nm complementary metal oxide semiconductor-based thin/thick gate oxide anti-fuse process were investigated using heavy ions and a picosecond pulsed laser. The cross sections of a single event upset (SEU) for radiation-hardened PROMs were measured using a linear energy transfer (LET) ranging from 9.2 to 95.6 MeV cm2 mg−1. The result indicated that the LET threshold for a dynamic bit upset was ~ 9 MeV cm2 mg−1, which was lower than the threshold of ~ 20 MeV cm2 mg−1 for an address counter upset owing to the additional triple modular redundancy structure present in the latch. In addition, a slight hard error was observed in the anti-fuse structure when employing 209Bi ions with extremely high LET values (~ 91.6 MeV cm2 mg−1) and large ion fluence (~ 1 × 108 ions cm−2). To identify the detailed sensitive position of a SEU in PROMs, a pulsed laser with a 5-μm beam spot was used to scan the entire surface of the device. This revealed that the upset occurred in the peripheral circuits of the internal power source and I/O pairs rather than in the internal latches and buffers. This was subsequently confirmed by a 181Ta experiment. Based on the experimental data and a rectangular parallelepiped model of the sensitive volume, the space error rates for the used PROMs were calculated using the CREME-96 prediction tool. The results showed that this type of PROM was suitable for specific space applications, even in the geosynchronous orbit.
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- 2019
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18. Research on Synergistic Development of New Industrialization and Scientific and Technological Talents
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Zhi-Qian Wang, Yun-Feng Gao, and Xiao-Yuan Li
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Engineering ,Industrialisation ,business.industry ,Economic system ,business - Published
- 2019
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19. Practice and Optimization Suggestion of Precise Poverty Alleviation in Jiangxi Province under the Rural Revitalization Strategy
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Yan Tang and Xiao-Yuan Li
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Economic growth ,Poverty ,Economics - Published
- 2019
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20. Volume change behaviour and microstructure of stabilized loess under cyclic freeze–thaw conditions
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Yan-xu Zhao, Sheng-Lin Wang, Xiao-yuan Li, Hassan Baaj, and Qingfeng Lv
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Materials science ,010504 meteorology & atmospheric sciences ,Loess ,0211 other engineering and technologies ,Geotechnical engineering ,02 engineering and technology ,Volume change ,Microstructure ,01 natural sciences ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,General Environmental Science ,Civil and Structural Engineering - Abstract
Freeze–thaw action is considered to be one of the most destructive actions that can induce significant damage in stabilized subgrades in seasonally frozen loess areas. Laboratory tests including frost heave – thaw shrinkage and microstructure change during freeze–thaw cycles were conducted to evaluate the volume change rate of loess stabilized with cement, lime, and fly ash under the impact of cyclic freeze–thaw conditions. The loess specimens collapsed after eight freeze–thaw cycles (192 h), but most stabilized loess specimens had no visible damage after all freeze–thaw cycles were completed. All of the stabilized loess samples underwent a much smaller volume change than the loess alone after the freeze–thaw cycles. Although surface porosity and equivalent diameter of stabilized loess samples increased, the stabilized loess can retain its microstructure during freeze–thaw cycles when the cement content was less than 6%. To ensure freeze–thaw resistance of stabilized loess subgrades, the mix proportions of the three additives was recommended to be 4 to 5% cement, 6% lime, and 10% fly ash.
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- 2016
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21. Association of AKT1 gene polymorphisms with sporadic Parkinson’s disease in Chinese Han population
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Xiao-Yuan, Li, Ji-Jun, Teng, Yang, Liu, Yu-Bin, Wu, Yu, Zheng, and An-Mu, Xie
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Male ,0301 basic medicine ,China ,General Neuroscience ,Parkinson Disease ,Middle Aged ,Polymorphism, Single Nucleotide ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Asian People ,Gene Frequency ,Humans ,Female ,Genetic Predisposition to Disease ,Proto-Oncogene Proteins c-akt ,Genetic Association Studies ,030217 neurology & neurosurgery - Abstract
Genetic variants of AKT1 have been shown to influence brain function of Parkinson's disease (PD) patients, and in this paper our aim is to investigate the association between the three single-nucleotide polymorphisms (rs2498799; rs2494732; rs1130214) and PD in Han Chinese. 413 Han Chinese PD patients and 450 healthy age and gender-matched controls were genotyped using the Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) method. Both the patient and control groups show similar genotype frequencies at the three loci: rs2498799, rs2494732 and rs1130214. We are able to identify a significant difference in the frequencies of genotype (p=0.019) and G allele (OR=0.764, 95% CI=0.587-0.995, p=0.045) both at rs2498799 between the patient and control groups. Furthermore, the association of subjects with GG genotypes versus those with GA+AA genotype remain significant after adjusting for age in the Han Chinese female cohort (OR=0.538, 95%CI=0.345-0.841, p=0.006), which is especially evident in the late-onset cohort (OR=0.521, 95%CI=0.309-0.877, p=0.012). In contrast, allele frequencies at rs2494732 and rs1130214 were similar between patients and controls in all subgroup analyses. These results suggest that polymorphism of AKT1 locus is associated with risk of PD and that the G allele at rs2498799 may decrease the risk of PD in the North-eastern part of Han Chinese female population.
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- 2016
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22. Role of bicyclol in preventing chemotherapeutic agent-induced liver injury in patients over 60 years of age with cancer
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Xiao-Yuan Li, Yingyi Wang, Hongyan Ying, Jian-feng Zhou, Yanping Zhou, Shuchang Chen, Mei Guan, and Lin Zhao
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Male ,medicine.medical_specialty ,Bilirubin ,medicine.medical_treatment ,Antineoplastic Agents ,Biochemistry ,Gastroenterology ,chemistry.chemical_compound ,Liver Function Tests ,Neoplasms ,Internal medicine ,medicine ,Humans ,In patient ,Prospective Studies ,Transaminases ,Aged ,Aged, 80 and over ,Liver injury ,Chemotherapy ,business.industry ,Incidence (epidemiology) ,Biphenyl Compounds ,Biochemistry (medical) ,Cancer ,Cell Biology ,General Medicine ,Middle Aged ,medicine.disease ,Surgery ,Liver ,chemistry ,Female ,Pre-Exposure Prophylaxis ,Liver function ,Chemical and Drug Induced Liver Injury ,business ,Serum transaminase - Abstract
Objective To evaluate the efficacy of bicyclol in preventing chemotherapy-induced liver damage. Methods Patients ≥60 years of age with cancer were equally randomized into control (chemotherapy alone) or prophylactic (chemotherapy supplemented with 75 mg bicyclol, oral, daily) groups. Liver function indices were assessed immediately before treatment, during each therapy cycle and following treatment. Results Of 306 patients enrolled, 300 patiets completed the study ( n = 147 and n = 153; prophylactic and control groups, respectively). Incidence of grade I–IV elevation of serum transaminase and/or bilirubin was significantly lower in the prophylactic group (17.1%) compared with the control group (47.1%). Incidence of grade II–IV hepatic injury was also significantly lower in the prophylactic group (0.7%) than in the control group (12.4%). Conclusions Prophylactic bicyclol (75 mg daily) could significantly reduce the incidence and degree of chemotherapeutic agent-induced liver damage in elderly patients with cancer. Further studies are recommended with larger sample sizes and long-term follow up.
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- 2014
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23. Two new isomerous fluorescent chemosensors for Al3+ based on photoinduced electron transfer
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Shuang-Quan Zang, Thomas C. W. Mak, Xiao-Yuan Li, Xiu-Juan Jiang, Hongwei Hou, and Hao Tang
- Subjects
Acetonitriles ,Magnetic Resonance Spectroscopy ,Light ,Analytical chemistry ,chemistry.chemical_element ,Electrons ,Crystallography, X-Ray ,Photoinduced electron transfer ,Analytical Chemistry ,chemistry.chemical_compound ,Isomerism ,Instrumentation ,Spectroscopy ,Fluorescent Dyes ,Detection limit ,Anthracene ,Nuclear magnetic resonance spectroscopy ,Fluorescence ,Sulfur ,Atomic and Molecular Physics, and Optics ,Crystallography ,Spectrometry, Fluorescence ,chemistry ,Proton NMR ,Spectrophotometry, Ultraviolet ,Titration ,Aluminum - Abstract
Two new isomerous PET fluorescent chemosensors (L and L') for Al(3+) have been designed, synthesized and characterized. The two chemosensors exhibited fluorescence enhancement upon binding Al(3+) in CH3CN by PET inhibition processes from both the sulfur and the nitrogen donors to anthracene. The job's plot, Benesi-Hildebrand plot and (1)H NMR titration experiments indicate that both chemosensors form a 1:1 complex with Al(3+). The binding constants were calculated to be (1.432±0.186)×10(5) and (1.427±0.970)×10(5), respectively. Furthermore, the lowest detection limit for Al(3+) in CH3CN was determined to be 4.8×10(-7)M and 2.2×10(-7)M, respectively.
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- 2013
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24. Two metal–organic coordination polymers assembled from a flexible iodo-dicarboxylate ligand and N-donor ancillary ligands
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Xiao-Yuan Li, Hong Xu, Yan Zhao, Shuang-Quan Zang, and Lu-Lu He
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chemistry.chemical_classification ,Halogen bond ,Hydrogen bond ,Stereochemistry ,Ligand ,Coordination polymer ,Supramolecular chemistry ,Polymer ,Inorganic Chemistry ,Supramolecular polymers ,Metal ,Crystallography ,chemistry.chemical_compound ,chemistry ,visual_art ,Materials Chemistry ,visual_art.visual_art_medium ,Physical and Theoretical Chemistry - Abstract
Two metal–organic coordination polymers, namely, {[Zn(L)(4,4′-bpy)1.5(H2O)]·H2O}n (1) and [Zn(L)(bpe)]n (2), have been hydrothermally synthesized through the reaction of 5-iodo-benzene-1,3-dioxyacetic acid (H2L) with divalent zinc salts in the presence of ancillary nitrogen ligands (4,4′-bpy = 4,4′-bipyridine, bpe = 1,2-bis(4-pyridyl)ethylene) and structurally characterized by elemental analysis, IR and X-ray diffraction. Complex 1 shows a metal–organic chain structure, the adjacent chains are further linked by hydrogen bonds and C−I⋯O halogen bonding to form a 3D supramolecular structure. Compound 2 contains interesting threefold parallel interpenetrated two-dimensional (2D) → two-dimensional (2D) network motifs which are united together to yield a 3D supramolecular structure through inter-layer C−H⋯O interactions. In addition, thermal analysis and photoluminescent properties of the complexes have also been investigated.
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- 2013
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25. Finite Element Numerical Simulation Analysis on Deformation of Adjacent Building with Shallow Foundation due to Excavation
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Yong Kang Yang, Wu Yang, Chun Yan Feng, and Xiao Yuan Li
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Engineering ,Computer simulation ,business.industry ,Foundation (engineering) ,Stiffness ,General Medicine ,Structural engineering ,Deformation (meteorology) ,Finite element method ,Displacement (vector) ,Shallow foundation ,medicine ,Geotechnical engineering ,medicine.symptom ,business ,Pile - Abstract
Based on deformation of adjacent building with shallow foundation of foundation pit excavation, Midas GTS is adopted to establish the finite element model. Through the numerical simulation, the maximum horizontal and vertical displacement in different conditions, Influence of different SMW pile stiffness and influence of different anchor position are analyzed. The results show that (1) horizontal deformation of SMW pile is decreased at the anchor construction; (2) compared with maximum horizontal displacement of SMW pile with 25a25b28a, the maximum horizontal displacement of SMW pile with 28b is increased by 50.9, 43.3, 11.5% respectively; (3) compared with the second anchor at 1.5, 3.5m, the horizontal displacement of adjacent building is minimal by the second anchor at 2.5m.
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- 2013
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26. Enhanced stability of benvitimod loaded nanoemulsion based on the PIT method
- Author
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Wen-Jing Li, Yue Zhang, Xiao-He Liu, Fu Yajing, Zhaohuan Niu, and Xiao-Yuan Li
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Materials science ,Benvitimod ,Chemical engineering ,Stability (probability) - Published
- 2016
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27. A Two-fold Interpenetrated Diamondlike 3D Metal-Organic Cd(II) Complex Based on 5-Iodo-isophthalic Acid and 1,3-Bi(4-pyridyl)propane
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Yan Zhao, Deng-Yong Zhu, Ming-Ming Dong, Xiao-Yuan Li, and Shuang-Quan Zang
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Hydrogen bond ,Infrared spectroscopy ,chemistry.chemical_element ,General Chemistry ,Nitrogen ,Metal ,Isophthalic acid ,Thermogravimetry ,chemistry.chemical_compound ,chemistry ,Propane ,Elemental analysis ,visual_art ,Polymer chemistry ,visual_art.visual_art_medium - Abstract
A metal-organic framework based on 5-iodo-isophthalic acid (5-iipaH2) and the ancillary nitrogen ligand 1,3-bi(4- pyridyl)propane (bpp), namely [Cd(5-iipa)(bpp)(H2O)]n (1), has been synthesized, and characterized by IR spectroscopy, elemental analysis, thermogravimetry, and X-ray crystallography. Complex 1shows a two-fold interpenetrating 3D diamond-like architecture that is stabilized by hydrogen bonding, μ...μ, I...μ, and C-H...p interactions.
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- 2012
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28. Influence of Cleanliness on Mechanical Property of 40CrNi2Mo Steel
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Xiao-yuan Li, Jie Shi, and Han Dong
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Mechanical property ,Materials science ,Mechanics of Materials ,Ultimate tensile strength ,Metallurgy ,Materials Chemistry ,Metals and Alloys ,Vacuum arc remelting ,Percentage reduction ,Tempering ,Composite material ,Strain hardening exponent - Abstract
40CrNi2Mo steels were prepared by vacuum arc remelting (VAR) and electroslag remelting (ESR). The cleanliness was evaluated and its effect on mechanical property of the two steels at different tempering temperature was investigated. The results show that because of cleanliness of the VAR steel is higher than that of the ESR steel, the impact absorbing energy (−40°C) and percentage reduction of area of the former are higher than the latter, while there is little influence of cleanliness on hardness, tensile strength, yield strength, yield-to-tensile-strength ratio and strain hardening exponent of the two steels.
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- 2007
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29. The Influence of La on the Corrosion Resistance of Hot-Dip Aluminized Steel
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Quan An Li, Jiu Ba Wen, Xiao Yuan Li, and Wei Zhang
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Materials science ,Mechanical Engineering ,Metallurgy ,Aluminized steel ,chemistry.chemical_element ,engineering.material ,Condensed Matter Physics ,Microstructure ,Corrosion ,chemistry ,Mechanics of Materials ,Aluminium ,visual_art ,Phase (matter) ,Aluminium alloy ,visual_art.visual_art_medium ,engineering ,General Materials Science ,Layer (electronics) - Abstract
The influence of the content of rare-earth La on the microstructure and corrosion-resistance of hot-dipped aluminum was studied in this paper .The results show that ,under the same technology conditions, the thickness of hot-dipped aluminizing layer by adding the appropriate content of rare-earth La is about 2~3 times as much as that without rare-earth La, and the microstructure of hot-dipped aluminizing layer has also greatly changed ,and a great deal of phase Fe3Al was precipitated along the boundary of a phase. The corrosion resistance of the hot-dipped layer with rare-earth La is greatly increased.
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- 2005
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30. Preparation of bowl-like and eggshell-like hollow carbon microspheres from potato starch
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Xiao-yuan Li, Shuo Zhao, Chengyang Wang, and Mingming Chen
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Thermogravimetric analysis ,Materials science ,Morphology (linguistics) ,Scanning electron microscope ,Mechanical Engineering ,chemistry.chemical_element ,Zinc ,Microporous material ,Condensed Matter Physics ,Microstructure ,behavioral disciplines and activities ,chemistry ,Chemical engineering ,Mechanics of Materials ,mental disorders ,embryonic structures ,Organic chemistry ,General Materials Science ,sense organs ,Potato starch ,Carbon - Abstract
Hollow carbon microspheres (HCS) were prepared from potato starch by ZnCl2 activation. The morphology and surface areas of the HCS were studied by scanning electron microscopy and N2 adsorption method, respectively. The results show that the HCS with bowl-like and eggshell-like structures are microporous materials. The preparation mechanism of the HCS was investigated by X-ray diffraction and thermogravimetric analysis. The results indicate that basic zinc chloride formed during impregnation decomposes into ZnO, HCl and H2O. ZnO and HCl play an important role in the preparation of the HCS. Moreover, removal of ZnO grains by HCl washing contributes to the total surface areas of the HCS.
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- 2012
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31. Crystal structure of cis -prenyl chain elongating enzyme, undecaprenyl diphosphate synthase
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Masahiro Fujihashi, Yuan-Wei Zhang, Xiao-Yuan Li, Kunio Miki, Tanetoshi Koyama, and Yoshiki Higuchi
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Models, Molecular ,Protein Conformation ,Stereochemistry ,Molecular Sequence Data ,Crystallography, X-Ray ,Catalysis ,Substrate Specificity ,chemistry.chemical_compound ,Protein structure ,Biosynthesis ,Prenylation ,Transferase ,Amino Acid Sequence ,Binding site ,Peptide sequence ,chemistry.chemical_classification ,Alkyl and Aryl Transferases ,Multidisciplinary ,Sequence Homology, Amino Acid ,ATP synthase ,biology ,Biological Sciences ,Micrococcus luteus ,Enzyme ,chemistry ,Biochemistry ,biology.protein - Abstract
Undecaprenyl diphosphate synthase (UPS) catalyzes the cis -prenyl chain elongation onto trans , trans -farnesyl diphosphate (FPP) to produce undecaprenyl diphosphate (UPP), which is indispensable for the biosynthesis of bacterial cell walls. We report here the crystal structure of UPS as the only three-dimensional structure among cis -prenyl chain elongating enzymes. The structure is classified into a protein fold family and is completely different from the so-called “isoprenoid synthase fold” that is believed to be a common structure for the enzymes relating to isoprenoid biosynthesis. Conserved amino acid residues among cis -prenyl chain elongating enzymes are located around a large hydrophobic cleft in the UPS structure. A structural P-loop motif, which frequently appears in the various kinds of phosphate binding site, is found at the entrance of this cleft. The catalytic site is determined on the basis of these structural features, from which a possible reaction mechanism is proposed.
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- 2001
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32. Clinical observation of the effect of CO 2 pneumoperitoneum on haemorrheology
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Guo‐Tai Chen, Philip Wai Yan Chiu, Liu‐Hua Chen, Zhi‐Mian Wu, and Xiao‐Yuan Li
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Red Cell ,business.industry ,Relative viscosity ,Blood viscosity ,medicine.disease ,Thrombosis ,body regions ,Pneumoperitoneum ,Co2 pneumoperitoneum ,Anesthesia ,medicine ,Deformity ,Surgery ,medicine.symptom ,business ,Blood gas analysis - Abstract
Objective: To discuss the relationship between CO2 pneumoperitoneum and haemorrheology and the possibility of thrombosis caused by CO2. Material and Methods: We compared indices of haemorrheology just prior to operation, 5 min after anaesthesia and 30 min after inflation or operation, and 24 h after operation. The indices included low-shear and high-shear whole-blood relative viscosity; plasma relative viscosity; red cell aggregation index; red cell filtration index; haematocrit; and blood gas analysis. We analysed the relationship between a variation in haemorrheology and CO2 pneumoperitoneum. Results: After pneumoperitoneum, blood viscosity and red cell aggregation index rises markedly and red cell deformity weakens markedly. Conclusion: Carbon dioxide pneumoperitoneum can cause an increase in blood viscosity, red cell aggregation and a weakening of red cell deformity, and may lead to thrombosis after laparoscopic surgery.
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- 2000
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33. [Correlation between KRAS mutations and clinicopathologic features in colorectal carcinomas]
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Jie, Gao, Jing, Zhang, Tao, Lu, Xiao-yuan, Li, Ning, Jia, and Zhi-yong, Liang
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Adult ,Aged, 80 and over ,Male ,Ovarian Neoplasms ,Genotype ,DNA Mutational Analysis ,Liver Neoplasms ,Adenocarcinoma ,Middle Aged ,Adenocarcinoma, Mucinous ,Proto-Oncogene Proteins p21(ras) ,Young Adult ,Sex Factors ,Proto-Oncogene Proteins ,Mutation ,ras Proteins ,Humans ,Female ,Codon ,Colorectal Neoplasms ,Aged - Abstract
To investigate mutations of KRAS gene and clinicopathological characteristics of colorectal carcinomas (CRC) in Chinese.Tumor cells were collected by microdissection from paraffin-embedded tumor specimens and adjacent normal colon tissues from 167 CRC patients. Genomic DNA was extracted and mutations of KRAS gene (codons 12 and 13) were detected by scorpions amplification refractory mutation system (Scorpions ARMS).KRAS mutations were identified in 66 patients (39.5%), including G13D (21 cases, 12.6%), G12D (15 cases, 9.0%), G12V (13 cases, 7.8%), G12C (6 cases, 3.6%), G12A (5 cases, 3.0%), G12S (4 cases, 2.4%) and G12R (2 cases, 1.2%). Female patients had a higher KRAS mutation rate than male (50.0%, 29/58 vs.33.9%, 37/109, P0.05). However, KRAS mutations did not correlate with the patient age, tumor sites, histological types and grades (P0.05). Additionally, 7 of 18 patients with metastatic CRC had KRAS gene mutations. Overall, KRAS gene mutation was identified in 59 patients among 149 primary CRC (39.6%). There was no significant difference in KRAS mutation between primary and metastatic tumors (P0.05).The detection rate of KRAS mutation is higher in female CRC patients than the males. The presence of KRAS mutation does not significantly correlate with the patients' age, tumor site, differentiation grades and histological types. There was no significant difference in KRAS mutation between the primary and metastatic tumors.
- Published
- 2012
34. Folfox4 regimen administered through combined hepatic arterial and systemic infusion for treatment of colorectal cancer with unresectable liver metastases
- Author
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Mei, Guan, Shu-Chang, Chen, Hong-Yan, Ying, Lin, Zhao, Xiao-Yuan, Li, Jian-Feng, Zhou, Ya-Juan, Shao, Xian-da, Yang, Yi, Lin, Xiao-Hong, Ning, and Chun-Mei, Bai
- Subjects
Adult ,Aged, 80 and over ,Male ,CA-19-9 Antigen ,Organoplatinum Compounds ,Liver Neoplasms ,Leucovorin ,Middle Aged ,Carcinoembryonic Antigen ,Hepatic Artery ,Antineoplastic Combined Chemotherapy Protocols ,Humans ,Infusions, Intra-Arterial ,Female ,Fluorouracil ,Colorectal Neoplasms ,Aged - Abstract
Hepatic arterial infusion chemotherapy for liver metastases is under evaluation because of the high target dose and low general toxicity. To investigate the efficacy and safety of a Folfox4 regimen administered through a combined hepatic arterial and systemic infusion for the first-line treatment of colorectal cancer (CRC) with unresectable liver metastases.Twenty-seven CRC patients with unresectable hepatic metastases and no prior chemotherapy were enrolled into the study. They received a Folfox4 regimen; 1st day: HAI of oxaliplatin 85 mg/m(2) and L-folinic acid 200 mg/m(2), followed by a bolus hepatic arterial injection of 5-fluorouracil 400 mg/m(2), then continuous HAI of 5-FU 600 mg/m(2); 2nd day: infusion of L-folinic acid 200 mg/m(2) i.v. followed by an intravenous bolus injection of 5-Fluorouracil 400 mg/m(2), then continuous infusion of 5-fluorouracil 600 mg/m(2) i.v. The patients received HAI during the odd cycles, and the intravenous administration of the same Folfox4 regimen during the even cycles.A total of 236 treatment cycles were given with a median of 10 cycles. The therapy generated the following results after six treatment cycles: complete response (CR) 1/27 (3.7%), partial response (PR) 17/27 (63.0%), stable disease (SD) 6/27 (22.2%), and progress disease (PD) 3/27 (11.1%). Five patients had hepatectomy. The serum levels of both carcinoembryonic antigen (CEA) and CA19-9 were significantly reduced (P0.05). A median time to progression of 11 months and a median overall survival of 24 months were documented. The major adverse events included grade 1/2 nausea/vomiting, upper abdominal pain, peripheral neuropathy, and neutropenia/thrombocytopenia.The Folfox4 regimen administered through combined hepatic arterial and systemic infusions is efficacious and safe for the treatment of CRC with unresectable liver metastases, and it facilitates the control of local lesions.
- Published
- 2012
35. Development of microsatellite markers for Lagerstroemia indica (Lythraceae) and related species
- Author
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Ming Cai, Xiao-Yuan Li, Huitang Pan, Yang Liu, Dan He, Wan Tang, and Qixiang Zhang
- Subjects
Lythraceae ,Genetic diversity ,microsatellite ,biology ,cross-transferrable ,Population genetics ,food and beverages ,Locus (genetics) ,Plant Science ,Lagerstroemia indica ,biology.organism_classification ,Primer Note ,lcsh:QK1-989 ,lcsh:Biology (General) ,lcsh:Botany ,Botany ,Microsatellite ,Lagerstroemia ,Allele ,lcsh:QH301-705.5 ,Ecology, Evolution, Behavior and Systematics ,SSR-enriched library - Abstract
Premise of the study: Microsatellite markers were developed and characterized to analyze genetic diversity within Lagerstroemia cultivars and related species. Methods and Results: Using simple sequence repeat (SSR)-enriched libraries, 11 species-specific polymorphic genomic SSRs were developed from L. indica ‘Hong Die Fei Wu’. All primers were tested on 48 L. indica individuals from China, the United States, and France. The primers amplified four to 12 alleles per locus, including di-, tri-, and tetranucleotide repeats. Observed and expected heterozygosities ranged from 0.1875 to 0.7609 and 0.2836 to 0.8385, respectively. The primers were also highly cross-transferrable to L. subcostata, L. limii, L. fauriei, L. caudata, and L. speciosa. Conclusions: The new primers will enlarge the bank of SSRs available to genetic research of Lagerstroemia. These SSR markers will facilitate population genetics and molecular marker-assisted selection of L. indica.
- Published
- 2012
36. Endostar combined with chemotherapy for treatment of metastatic colorectal and gastric cancer: a pilot study
- Author
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Jian-Feng, Zhou, Chun-Mei, Bai, Yu-Zhou, Wang, Xiao-Yuan, Li, Yue-Juan, Cheng, and Shu-Chang, Chen
- Subjects
Adult ,Male ,Treatment Outcome ,Stomach Neoplasms ,Antineoplastic Combined Chemotherapy Protocols ,Humans ,Antineoplastic Agents ,Female ,Middle Aged ,Colorectal Neoplasms ,Aged ,Endostatins - Abstract
Antiangiogenesis is a promising field of cancer therapy. Endostar, a novel recombinant human endostatin, is one of the few approved drugs acting as angiogenesis inhibitors of cancer in China. However, there are few clinical studies about Endostar in gastrointestinal cancer. This pilot study aimed to evaluate the efficacy and safety of the combination of Endostar and chemotherapy in patients with metastatic colorectal and gastric cancers.From March 2007 to October 2009, 23 patients were enrolled. Patients received Endostar intravenously at a dose of 15 mg daily from day 1 to 14 and day 1 to 7 when combined with 3- and 2-week chemotherapy regimens, respectively, which were determined according to patients' previous chemotherapy history. Treatment was repeated until disease progression, unacceptable toxicity or patients' refusal.Seven, six and ten patients received Endostar as first-, second- and third-line therapy, respectively. A total of 75 cycles were administered. Twenty-one patients were assessable for responses. The overall response rate and disease control rate were 19.0% and 47.6%, respectively. All the four partial responses were among patients receiving Endostar as first-line therapy, whose response rate was 57.1%. The median time to progression and overall survival were 2.6 months (95%CI, 2.0 - 3.2 months) and 10.3 months (95%CI, 3.9 - 16.7 months), respectively. Toxicity was tolerable, with grade 3-4 toxicities observed for leucopenia (30.4%), neutropenia (34.8%), thrombocytopenia (17.4%) and anemia (13.0%). Three patients (13.0%) encountered transient sinus bradycardia with spontaneous remission.Endostar combined with chemotherapy is well-tolerated in patients with metastatic colorectal and gastric cancers, and it is relatively effective as a first-line therapy.
- Published
- 2012
37. Similarity of Macaque Face Images based on PCA
- Author
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Xiao Yuan Li, Zhen Long Wang, Jia Qi Zhang, and H. Yu Xia
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education.field_of_study ,biology ,business.industry ,Computer science ,Speech recognition ,Population ,General Engineering ,Value (computer science) ,Pattern recognition ,Linear subspace ,Macaque ,Image (mathematics) ,Similarity (network science) ,biology.animal ,Face (geometry) ,Artificial intelligence ,education ,business ,Mathematics ,Block (data storage) - Abstract
In this Work, Block PCA Based Method is Used to Build Several Subspaces for each Macaque Face Image and a Similarity Criterion is Proposed to Distinguish Family Properties of Macaques. A Proper Threshold Value is Determined through Statistical Analysis. then, a Series of Experiments are Carried out to Verify the Feasibility of this Approach. the Results Demonstrate that it is Proper to Utilize Similarity Value as Judgment Criterion of Macaque Family Properties and Higher Accurate Rate is Obtained. it can Provide an Effective way for Population Recognition of other Species.
- Published
- 2012
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38. Solid malignancies complicated with pulmonary embolism: clinical analysis of 120 patients
- Author
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Shui-qing, Ma, Yi, Lin, Hong-yan, Ying, Ya-juan, Shao, Xiao-yuan, Li, and Chun-mei, Bai
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Adult ,Aged, 80 and over ,Male ,Adolescent ,Heparin ,Anticoagulants ,Middle Aged ,Young Adult ,Child, Preschool ,Neoplasms ,Humans ,Female ,Child ,Pulmonary Embolism ,Aged - Abstract
Pulmonary embolism, a potentially fatal event, occurs more frequently in cancer patients than in the general population. To offer an accurate diagnosis and effective treatment to such patients in China, we analyzed the incidence rate and clinical features of pulmonary embolism in patients with solid tumor hospitalized in the Peking Union Medical College (PUMC) Hospital.A retrospective analysis was made of the hospitalized patients with solid malignancies complicated with pulmonary embolism who had been admitted into the PUMC Hospital from January 2002 to December 2008.The incidence of pulmonary embolism in hospitalized patients with solid malignancies was 0.27% (120/43 967). The median age at diagnosis was 57.5 years. The male to female ratio was 1.0:1.4 (49:71). Patients with non-small-cell lung cancer (NSCLC) constituted the largest proportion of the 120 patients (37.5%), followed by patients with breast (9.2%), ovarian (8.3%), pancreatic (6.7%), and liver cancer (6.7%). Eighty patients (66.7%) had stage IV cancer. Bone was the most common site of distant metastasis (46.3%). D-dimer level was elevated in 90.9% of the 66 tested patients. The incidence of bleeding due to anti-coagulation therapy was 3.6%. Thirty-six (30.0%) of the 120 patients had concurrent deep venous thrombosis in the lower extremities. Seventeen patients developed acute pulmonary embolism within 2 weeks after surgery, 3 of whom died suddenly. Four patients presented with deep venous thrombosis and 1 with pulmonary embolism prior to the identification of malignancy.Patients with cancer of the lung, ovarian, breast, pancreas, and liver are more likely to be complicated with pulmonary embolism than those with other types of solid tumors. Patients with distant metastasis are at a higher risk of pulmonary embolism. Pulmonary embolism without concurrent deep venous thrombosis is more frequently observed than concurrence of both disorders in the clinical setting.
- Published
- 2010
39. A bulky bis-pocket manganese(V)-oxo corrole complex: observation of oxygen atom transfer between triply bonded Mn(V)[triple bond]O and alkene
- Author
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Hai-Yang, Liu, Fei, Yam, Yu-Tao, Xie, Xiao-Yuan, Li, and Chi K, Chang
- Subjects
Oxygen ,Manganese ,Porphyrins ,Molecular Structure ,Alkenes ,Spectrum Analysis, Raman - Abstract
The highly bulky bis-pocket corrole 5,10,15-tris(2,4,6-triphenylphenyl)corrole (H(3)TTPPC) has been synthesized. Resonance Raman spectroscopy revealed a triply bonded Mn[triple bond]O moiety in its manganese(V)-oxo complex. Direct oxygen atom transfer from (TTPPC)Mn[triple bond]O to styrene was confirmed by an (18)O-labeling experiment. The (TTPPC)Mn(III) complex also exhibits significant shape selectivity in the catalytic epoxidation of nonconjugated dienes.
- Published
- 2009
40. THE UNIFIED SCHEME OF THE EFFECTIVE ACTION AND CHIRAL ANOMALIES IN ANY EVEN DIMENSIONS
- Author
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Xiao-yuan Li, Han-Ying Guo, Kuang-Chao Chou, Ke Wu, and Xing-Chang Song
- Subjects
Physics ,Pseudoscalar ,Theoretical physics ,High Energy Physics::Lattice ,Skyrmion ,High Energy Physics::Phenomenology ,Goldstone boson ,Homomorphism ,Abelian group ,Anomaly (physics) ,Space (mathematics) ,Effective action - Abstract
Based on the Weil homomorphism method, a unified scheme in which all the important topological properties of the pseudoscalar Goldstone boson and gauge fields in even dimensional space are described in one remarkably compact form is given. These properties include the effective action, the skyrmion anomalous current, Abelian anomaly, symmetric and asymmetric non-Abelian chiral anomalies, and anomaly free conditions.
- Published
- 2009
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41. [Post-operative adjuvant treatment with oxaliplatin, fluorouracil, and leucovorin for local advanced gastric cancer]
- Author
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Lin, Zhao, Xiao-yuan, Li, Chun-mei, Bai, and Shu-chang, Chen
- Subjects
Adult ,Male ,Organoplatinum Compounds ,Leucovorin ,Middle Aged ,Survival Analysis ,Drug Administration Schedule ,Oxaliplatin ,Young Adult ,Treatment Outcome ,Chemotherapy, Adjuvant ,Stomach Neoplasms ,Antineoplastic Combined Chemotherapy Protocols ,Humans ,Female ,Fluorouracil ,Infusions, Intravenous ,Aged ,Follow-Up Studies ,Retrospective Studies - Abstract
To evaluate the toxicity and efficacy of combination regimen with oxaliplatin plus fluorouracil and leucovorin(FOLFOX) as post-operative adjuvant chemotherapy in local advanced gastric cancer.Twenty-five gastric cancer patients, 2 at the stage II, 17 at the stage III, and 6 at the stage IV received the FOLFOX regimen after surgery: intravenous infusion of oxaliplatin 85 mg/m2 for 2 h on day 1, intravenous infusion of leucovorin 200 mg/m2 for 2 h on days 1-2, and intravenous bolus injection of 5-fluorouracil (5-FU) 400 mg/m2 on days 1-2, and continuous infusion of 5-FU 600 mg/m2 for 22 h on days 1-2; and this regimen was repeated every 2 weeks. The effect and adverse reactions were recorded.The median disease free survival time and overall survival time were 26.0 months and 38.0 months respectively. The frequent grade 3/4 toxicity of the FOLFOX regimen included: neutropenia (12.4%), thrombocytopenia (8.2%), and nausea (7.5%).The post-operative adjuvant chemotherapy of FOLFOX regimen has expectable efficacy in treatment of gastric cancer with light and well tolerable toxicity.
- Published
- 2008
42. [Expression of transcription factors T-bet/GATA-3 mRNA and its effect on Tc1/Tc2 balance in asthmatic children]
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Wei-Ping, Tan, Xian-di, Mai, Bao-Qing, Wu, Xiao-Yuan, Li, Jing, Li, Jing, Wei, Hua-Rong, Huang, and Shao-Liang, Huang
- Subjects
Male ,Adolescent ,Case-Control Studies ,Child, Preschool ,Humans ,Female ,GATA3 Transcription Factor ,RNA, Messenger ,Child ,T-Box Domain Proteins ,Asthma ,T-Lymphocytes, Cytotoxic - Abstract
In contrast to CD(4)(+) helper T-lymphocytes (T(H)), little is known about the transcriptional regulation of CD(8)(+) cytotoxic T-lymphocytes (Tc) and its role in the pathogenesis of asthma is unclear. This study was conducted to investigate the effect of T-bet and GATA-3 mRNA expression on profiles of type 1 and type 2 cytotoxic T lymphocytes in asthmatic children.Totally 38 asthmatic children, including acute attack group composed of 20 cases (age 3 - 13 years, mean 6.2 +/- 2.9), remission group with 18 cases (age 3 - 12 years, mean 6.1 +/- 2.5) and 20 healthy control children (age 3 - 12, 6.9 +/- 2.7) were recruited in this study from Sep. 2005 to Mar. 2006. The mRNA expression of T-bet and GATA-3 in the peripheral blood mononuclear cells were detected by using semi-quantitative PCR and Tc1, Tc2 cell numbers by flow cytometry analysis system.T-bet mRNA in asthmatic children was lower than that in control group and lower in attack stage than in remission stage (0.14 +/- 0.04, 0.21 +/- 0.03, 0.28 +/- 0.03, P0.05). In contrast, GATA-3 mRNA was higher in asthmatic children than in control group and higher in attack stage than in remission stage (0.49 +/- 0.09, 0.44 +/- 0.08, 0.37 +/- 0.04, P0.05). It was shown that Tc1 percentage was lower in asthmatic children than those of control group and lower in attack stage than those of remission stage (6.6 +/- 2.4, 14.2 +/- 4.3, 31.2 +/- 3.8, P0.05). Tc2 percentage in asthmatic children was higher than that of control group and higher in attack stage than that of remission stage (10.0 +/- 4.2, 5.4 +/- 2.2, 3.5 +/- 1.1, P0.05). Spearman correlation analysis revealed that T-bet mRNA was positively correlated with Tc1 percentage (r = 0.704) and negatively correlated with Tc2 percentage (r = -0.629). GATA3 mRNA was negatively correlated with Tc1 percentage (r = -0.612) and positively correlated with Tc2 percentage (r = 0.673). The T-bet/GATA-3 mRNA ratio was positively correlated with Tc1 percentage (r = 0.731) and Tc1/Tc2 (r = 0.773), while negatively correlated with Tc2 percentage (r = -0.642).The imbalance of T-bet/GATA-3 mRNA expression is closely correlated with skewed Tc2 dominance in asthmatic children.
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- 2007
43. The Influence of La on the Corrosion Resistance of Hot-Dip Aluminized Steel
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Jiu ba Wen, Wei Zhang, Xiao Yuan Li, and Quan An Li
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- 2005
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44. Synthesis and structural characterization of di- and tetranuclear zinc complexes with phenolate and carboxylate bridges. Correlations between 13C NMR chemical shifts and carboxylate binding modes
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Bao-Hui, Ye, Xiao-Yuan, Li, Ian D, Williams, and Xiao-Ming, Chen
- Abstract
Two di- and a tetranuclear zinc-carboxylate complexes with different coordination modes, [Zn(2)L(mu(1,3)-OAc)(2)](ClO(4)) (1), [Zn(2)L(mu(1,3)-Pro)(2)](ClO(4)) (2), and [Zn(2)L(mu(1,1)-HCO(2))(mu(1,3)-HCO(2))](2)(ClO(4))(2) (3) (where L = 2,6-bis(N-2-(2'-pyridylethyl)formimidoyl)-4-methylphenol, OAc = acetate, and Pro = propionate) have been synthesized. Their compositions and structures have been identified by elemental analyses, IR, NMR, and X-ray single-crystal diffraction. The cations in both 1 and 2 reveal that the two zinc ions are assembled by a phenolate and a pair of syn-syn mu(1,3)-carboxylate bridges with metal-metal distances of 3.281 and 3.331 A, respectively, and each polyhedron around the zinc ion is a slightly distorted trigonal bipyramid. Compound 3 is a tetranuclear complex consisting of two identical dinuclear subunits that connect to each other by the two formate groups. In each subunit, the pair of metal ions separated at 3.130(1) A is assembled by a phenolate oxygen from L, and a monodentate and a syn-syn bidentate formate bridges. The formate group displays a novel tridentate mode, namely, monodentate and syn-anti bidentate bridges. On the other hand, the solid-state (13)C NMR technique was employed to distinguish the different binding modes of acetate group in five-coordinate zinc complexes. The chemical shifts are as follows: chelating mode (ca. 184 ppm)bidentate bridge (ca. 180 ppm)monodentate bridge (ca. 176 ppm).
- Published
- 2002
45. Unsupervised synthetic aperture radar image segmentation with superpixels in independent space based on independent component analysis
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Jian Ji and Xiao-yuan Li
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Synthetic aperture radar ,business.industry ,Computer science ,Segmentation-based object categorization ,Feature extraction ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Scale-space segmentation ,Image processing ,Pattern recognition ,Speckle noise ,Image segmentation ,ComputingMethodologies_PATTERNRECOGNITION ,Computer Science::Graphics ,Minimum spanning tree-based segmentation ,Computer Science::Computer Vision and Pattern Recognition ,General Earth and Planetary Sciences ,Computer vision ,Artificial intelligence ,business - Abstract
Synthetic aperture radar (SAR) image segmentation is a challenging problem in recent years because of the speckle noise. An unsupervised SAR image segmentation with superpixels by independent component analysis (ICA) is proposed. ICA independent space is proposed to represent SAR images for feature extraction effectively. First, the SAR image is divided into small regions by mean-shift algorithm and then those regions are merged in region adjacent graph and full-connected graph based on the Mining Spanning Tree theory, which balances the speed and quality of segmentation. Finally, experiments on X-band TerraSAR images and comparisons with simple linear iterative clustering and graph-cut illustrate the excellent performance of the new method.
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- 2014
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46. Chain length determination of prenyltransferases: both heteromeric subunits of medium-chain (E)-prenyl diphosphate synthase are involved in the product chain length determination
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Tanetoshi Koyama, Xiao-Yuan Li, and Yuan-Wei Zhang
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Stereochemistry ,Protein subunit ,Molecular Sequence Data ,Bacillus subtilis ,Biochemistry ,Catalysis ,Hemiterpenes ,Organophosphorus Compounds ,Prenylation ,Polyisoprenyl Phosphates ,Amino Acid Sequence ,chemistry.chemical_classification ,Alkyl and Aryl Transferases ,biology ,ATP synthase ,biology.organism_classification ,Dimethylallyltranstransferase ,Peptide Fragments ,Recombinant Proteins ,Amino acid ,Kinetics ,Micrococcus luteus ,Heptaprenyl diphosphate synthase ,Enzyme ,chemistry ,biology.protein ,Mutagenesis, Site-Directed ,Dimerization ,Sesquiterpenes - Abstract
Among prenyltransferases, medium-chain (E)-prenyl diphosphate synthases are unusual because of their heterodimeric structures. The larger subunit has highly conserved regions typical of (E)-prenyltransferases. The smaller one has recently been shown to be involved in the binding of allylic substrate as well as determining the chain length of the reaction product [Zhang, Y.-W., et al. (1999) Biochemistry 38, 14638-14643]. To better understand the product chain length determination mechanism of these enzymes, several amino acid residues in the larger subunits of Micrococcus luteus B-P 26 hexaprenyl diphosphate synthase and Bacillus subtilis heptaprenyl diphosphate synthase were selected for substitutions by site-directed mutagenesis and examined by combination with the corresponding wild-type or mutated smaller subunits. Replacement of the Ala at the fifth position upstream to the first Asp-rich motif with bulky amino acids in both larger subunits resulted in shortening the chain lengths of the major products, and a double combination of mutant subunits of the heptaprenyl diphosphate synthase, I-D97A/II-A79F, yielded exclusively geranylgeranyl diphosphate. However, the combination of a mutant subunit and the wild-type, I-Y103S/II-WT or I-WT/II-I76G, produced a C(40) prenyl diphosphate, and the double combination of the mutants, I-Y103S/II-I76G, gave a reaction product with longer prenyl chain up to C(50). These results suggest that medium-chain (E)-prenyl diphosphate synthases take a novel mode for the product chain length determination, in which both subunits cooperatively participate in maintaining and determining the product specificity of each enzyme.
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- 2000
47. Site-directed mutagenesis of the conserved residues in component I of Bacillus subtilis heptaprenyl diphosphate synthase
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Yuan-Wei Zhang, Hiroshi Sugawara, Xiao-Yuan Li, and Tanetoshi Koyama
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Hot Temperature ,Molecular Sequence Data ,Prenyltransferase activity ,Bacillus subtilis ,Biochemistry ,Conserved sequence ,Substrate Specificity ,Protein structure ,Enzyme Stability ,Amino Acid Sequence ,Site-directed mutagenesis ,Protein Structure, Quaternary ,Conserved Sequence ,chemistry.chemical_classification ,Alkyl and Aryl Transferases ,ATP synthase ,biology ,Sequence Homology, Amino Acid ,biology.organism_classification ,Recombinant Proteins ,Amino acid ,Kinetics ,Heptaprenyl diphosphate synthase ,chemistry ,Amino Acid Substitution ,biology.protein ,Mutagenesis, Site-Directed - Abstract
Heptaprenyl diphosphate synthase of Bacillus subtilis is composed of two dissociable heteromeric subunits, component I and component II. Component II has highly conserved regions typical of (E)-prenyl diphosphate synthases, but it shows no prenyltransferase activity alone unless it is combined with component I. Alignment of amino acid sequences for component I and the corresponding subunits of Bacillus stearothermophilus heptaprenyl diphosphate synthase and Micrococcus luteus B-P 26 hexaprenyl diphosphate synthase shows three regions of high similarity. To elucidate the role of these regions of component I during catalysis, 13 of the conserved amino acid residues in these regions were selected for substitution by site-directed mutagenesis. Kinetic studies indicated that substitutions of Val-93 with Gly, Leu-94 with Ser, and Tyr-104 with Ser resulted in 3-10-fold increases of K(m) values for the allylic substrate and 5-15-fold decreases of V(max) values compared to those of the wild-type enzyme. The three mutated enzymes, V93G, L94S, and Y104S, showed little binding affinity to the allylic substrate in the membrane filter assay. Furthermore, product analyses showed that D97A yielded shorter chain prenyl diphosphates as the main product, while Y103S gave the final product with a C(40) prenyl chain length. These results suggest that some of the conserved residues in region B of component I are involved in the binding of allylic substrate as well as determining the chain length of the enzymatic reaction product.
- Published
- 1999
48. Nerve welding by Ar<formula><roman>+</roman></formula> laser
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Gue-Xiang Xu, Xiao-Yuan Li, Ai-Hua Zhang, Dong-Ji Wei, and Zue-Xing Deng
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Argon ,Quartz fiber ,Materials science ,technology, industry, and agriculture ,Laser beam welding ,chemistry.chemical_element ,Welding ,Anatomy ,respiratory system ,Laser ,law.invention ,Suture (anatomy) ,chemistry ,law ,Sciatic nerve ,Laser beams ,Biomedical engineering - Abstract
techniques was made on rats. Total tests included electrophysiological and histopathological studies. The result of theexperiment showed that nerve welding with laser is better than conventional suture techniques.Key words: Ar laser, laser welding, sciatic nerve, rat1. INTRODUCTIONThe main drawback of conventional microsurgical suture repair of nerve is that the suture of operation stay on theanastemotic epineurial. It is the of foreign body reaction. Because they are the gap between suture the regenerated neuraxoncomes out of the neurotube often when it identify the far end of nerve inner tube and the connective tissue hyperpigsia at therepair site Therefore many people try to make nerve repaired with the laser welding of different wavelength [1-4]. Thisstudy was designed to investigate the sciatic nerve of rat welded by Ar laser.2. MATERIALS AND METHODS2.1 Equipment of laser weldingAn argon ion (Ark) laser (model 360) of 488.Onm wavelength was used. The laser beam is focused to a optic deliverysystem of quartz fiber (600j.tm) The laser output is 700mW. The pacula of welding place is 1mm. In each welding point theirradiating time is 0.5 sec controlled by a model SDK-2 interval timer
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- 1998
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49. Formation of a novel tetranuclear iron(III) complex with a μ4-PO4 bridge from 4-nitrophenyl phosphate
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Bao-Hui Ye, Xiao-Yuan Li, Feng Xue, and Thoms C. W. Mak
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Tris ,Stereochemistry ,Metals and Alloys ,General Chemistry ,Crystal structure ,Phosphate ,Catalysis ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,Hydrolysis ,chemistry ,Polymer chemistry ,Materials Chemistry ,Ceramics and Composites ,Nitrophenyl phosphate ,Amine gas treating - Abstract
A novel tetranuclear iron(III) complex, [{Fe2(tren)2(µ-O)}2(µ4-PO4)][ClO4]5·2.5H2O 1 [tren = tris(2-aminoethyl)amine], is synthesized; X-ray crystal structure analysis reveals that 1 contains a tetranuclear cation in which the iron atoms are linked by a µ4-PO43– bridge, which is a hydrolytic product from 4-nitrophenyl phosphate.
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- 1997
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50. The Unified Scheme of the Effective Action and Chiral Anomalies in any Even Dimensions
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Kuang-Chao Chou, Xing-Chang Song, Ke Wu, Xiao-yuan Li, and Han-Ying Guo
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Physics ,Chiral anomaly ,Particle physics ,Physics and Astronomy (miscellaneous) ,High Energy Physics::Lattice ,Skyrmion ,High Energy Physics::Phenomenology ,Mixed anomaly ,Theoretical physics ,Goldstone boson ,Anomaly (physics) ,Chiral symmetry breaking ,Effective action ,Gauge anomaly - Abstract
Based on the Weil homomorphism method, a unified scheme in which all the important topological properties of the pseudoscalar Goldstone boson and gauge fields in even dimensional space are described in one remarkably compact form is given. These properties include the effective action, the skyrmion anomalous current, Abelian anomaly, symmetric and asymmetric non-Abelian chiral anomalies, and anomaly free conditions.
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- 1984
- Full Text
- View/download PDF
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