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Objective To explore the effect of short-term semi-immersion teaching and training based on the learning pyramid model to improve the capacity building of to find early gastric cancer by digestive endoscope physicians. Methods Thirty digestive refresher doctors were randomly selected from our center for 4-week semi-immersion training. The capacity of the trainees to recognize early gastric cancer was tested before and after 4 weeks of training, and the accuracy of the test was compared. Results The accuracy of the test before training, after theoretical lesson and after 4 weeks of training were 44.58%±16.39%, 48.54%±16.95% and 68.75%±12.06% respectively. The test accuracy after theory lesson plus 4 weeks of training was higher than that before training and after only theoretical lesson (P＜0.001).The test accuracy after theoretical lesson was higher than that before the training(P＜0.05). When grouping by the number of cases in previous gastroscopy, no matter before training or after theoretical lesson, the test accuracy with experience in testing was higher than group with less experience. However, the test accuracy of the two groups almost reached a same level after 4 weeks of training(P＜0.01). With the extension of training time, the test accuracy gradually increased (P＜0.001). There was an interaction between grouping and training time (P＜0.001).In the correlation analysis, the number of cases of the previous gastroscopy performance was positively correlated with the test accuracy before training and after theoretical lesson (r=0.668,＜0.001,r=0.581, P＜0.01). Conclusions Semi-immersion training guided by the learning pyramid model can effectively improve the capacity of digestive endoscope physicians to recognize early gastric cancer.

Second-order nonlinear optics is a crucial technique for light frequency conversion with broad applications in scientific research and technological advancements. Monolayer transition metal dichalcogenides exhibit extraordinarily high second-order nonlinear susceptibilities, indicating their significant potential for efficient nonlinear optical response. Maintain the giant nonlinear coefficient of monolayer, expand material thickness and frequency response region, and improve nonlinear response is an important challenge. This paper presents an overview of the regulation of second-order nonlinear optical effects based on monolayer transition metal dichalcogenides. We discuss the frequency dependence of monolayer transition metal dichalcogenides, as well as multi-layer stacking of different symmetric phases. Additionally, we summarize the potential applications of their nonlinear optical effects. [ABSTRACT FROM AUTHOR]

To implement the thought of people-oriented, to carry out the scheme of high-quality applied talents, and to achieve the training goal of independent colleges, the reform and innovation of experimental teaching pattern and promotion of experimental teaching quality are important initiatives to cultivate students' innovation consciousness and innovative ability. This paper analyzed the problems of independent college laboratories in their opening process. The problems contained that lab resources were not concentrated, laboratory staff were not enough and measures lacked for incentiving corresponding teachers. Zhijiang college optimized and integrated experimental resource, set up an opening experimental platform, established experimental management system and encouraged the students to participate in the opening experimental teaching. The students achieved remarkable results by participating in the practice of open experimental teaching activities. A new approach to experimental teaching and the talent cultivation of independent colleges had been explored. [ABSTRACT FROM AUTHOR]

Well Fenghuang-X1 is a risk exploratory well in Fuyang exploratory area. In the drilling process, some problems were met, such as stratum uncertainty, poor drillability and grindability of Middle Paleozoic strata, uncontrollable trajectory of big size wellbore with diameter of 311.1 mm, coal mudstone collapse, mass leaking layers, etc. Based on the analyses on the strata characteristics and drillability, the efficient PDC bit and roller bit were selected. For the reasons of uncertainty of deflecting capacity and uncontrollable well track using normal BHA in big size wellbore and hard strata, the new single bending bistable BHA which increased the distance between two centralizers was taken into usage. The methods of plugging while drilling, pressure sealing and novel explosive plugging were taken as plugging methods. The treatments above were taken to raise mud density, and to enhance mud inhibition capacity and anti-collapsing and sealing capacity. The application of the drilling technique on Well Fenghuang-X1 was successful, and offered some experience for drilling similar type of wells. [ABSTRACT FROM AUTHOR]

As one of the common traumatic diseases in clinical practice, peripheral nerve injury (PIN) often causes nerve pain, abnormal reflexes, autonomic disorders, and even sensorimotor disorders due to the slow regeneration rate after injury, which seriously affects body function. Even as the gold standard of treatment, autologous nerve transplantation has limitations such as limited donor area and donor injury, which greatly limits its clinical application effect. Therefore, the preparation of artificial nerve grafts suitable for clinical practice has become the future development trend of peripheral nerve injury treatment, and the repair of injury defects and the promotion of nerve regeneration have also become research hotspots in tissue engineering and regenerative medicine. In recent years, extensive research has been carried out on nerve guidance conduits (NGCs) in the field of nerve regeneration and repair, in which scaffold materials and internal fillers have also become the focus of research as the core elements of neural catheters, and a series of achievements have been made in the application of new materials, embedding stem cells/precursor cells, and developing trophic factors and drug-loaded sustained-release systems. Therefore, this paper focuses on the application progress of hydrogel and its related derivative materials in the field of peripheral nerve injury repair, and provides new ideas for promoting the related research of tissue engineering and clinical medicine.

Objective: To evaluate the regulation efficacy of oral tangeretin on testosterone and cortisol in sprinters at winter training season. Methods: Twenty-four sprinters were paired and randomly divided into experimental group (EG) and control group (CG). During winter training season, EG were treated with 200 mg tangeretin by oral, and CG were treated with placebo for 4 weeks. Blood samples were collected on the first day of each week (T1, T2, T3, T4) and after the intervention (T5) to detect serum levels of testosterone, cortisol, superoxide dismutase (SOD), and adrenocorticotropic hormone (ACTH). The body composition was tested at T1 and T5. Results: After 4 weeks, ①the serum cortisol level of CG was increased, and the serum levels of testosterone and SOD were decreased significantly ( P ＜0.05). ②In EG, the serum levels of cortisoland ACTH were decreased significantly ( P ＜0.05, P ＜ 0.01), while the serum testosterone level was remained stable, and the level of SOD was increased slightly. ③The muscle mass of EG and CG were increases, but that of EG was increased higher than that of CG. Conclusion: Tangeretin reduces the oxidative stress response that caused by high-intensity exercise during winter training, which maintain the serum testosterone level and inhibit cortisol excessive secretion and promote muscle synthesis.

Dendroclimatology is one of the important methods for studying climate changes in the past. Previous studies showed that tree-ring density is an important proxy for temperature in the growing season. In this study, we established 132-135 years chronologies of tree-ring maximum density, the minimum density, the latewood and the earlywood average density of Picea crassifolia at the western Qilian Mountains. We compared the climatic signal and its seasonal best combination of different tree-ring density chronologies, and evaluated their potential values as climate proxies. The responses of tree-ring latewood average density and the earlywood average density to climate signals during the growing season were much lower than that of tree-ring maximum and the minimum den-sity. The tree-ring earlywood average density and the minimum density had a strong relationship with the Palmer drought index, indicating that the earlywood average density and the minimum tree-ring density had the potential as substitute indicators for drought.

Age is the sole criterion for identifying ancient trees. Dendrochronology was used to examine the age of the old trees of Pyrus ussuriensis in the Fourth group of Doujiadun Village (formerly Yangjiayuanzi), Mogao Town, Dunhuang City. As all the old pear trees had been decayed and hollow, we collected cores of P. ussuriensis of different ages to establish the age-related curve of tree radial growth, and estimated the number of tree rings in the missing segment. Combined with accurate count on tree rings, the age of P. ussuriensis was restored. The results showed that the average age of the 13 old pear trees in the orchard was (280±35) years, presenting further evidence for the record about old pear trees in Dunhuang Zhi . These old trees could be classified as the third-class ancient tree according to tree age, and should be properly protected and preserved. This study provided a detailed scientific basis to resolve the dispute over the conservation of ancient P. ussuriensis in Dunhuang City.

The stem radius growth of Pinus tabuliformis was monitored by dendrometer during the growing season in 2017 and 2018 at two altitudes (2010 and 2330 m) in the Helan Mountains. We investigated the responses of tree radial growth to drought events. The results showed that drought event in June 2018 reduced stem growth rate of P. tabuliformis . The precipitation in July and August reactivated the stem radius growth. The main growing season of P. tabuliformis stem was June-August in 2018, which was a month longer than that in 2017. The response patterns between stem radial growth of P. tabuliformis and climatic factors were consistent across forest stands in different altitudes. Drought in the early growing season suppressed the radial growth of trees, while precipitation in the mid- and late growing seasons played an important role in promoting the radial growth of trees. The effects of climatic factors in August on tree-ring width should be considered during climate reconstruction in this region.

Objective: To analyze the influence of preoperative serum nutritional indexes and postoperative nutritional guidance on 1-year mortality in elderly patients with hip fracture., Methods: From January 2015 to December 2017, 396 elderly patients with hip fracture were included in the study, including 267 females and 129 males, aged 68 to 80(75.48±2.62) years; the course of disease was 2 to 10 (6.12±1.35) days;all patients were followed up for 1-year, and were divided into death group and survival group according to whether the patients died or not. Multivariate logistic regression model was used to analyze the influencing factors of 1 year mortality., Results: Duringthe follow-up, 4 patients lost contact and were treated as shedding, among which 67 patients died and 325 patients survived. The age, male patients, patients with more than three basic diseases, American Society of Anesthesiologists grade Ⅲ-Ⅳ and patients with postoperative complications in the death group were significantly higher than those in the survival group (all P <0.05). There was no significant difference in body mass index(BMI), number of smokers, fracture type and operation type (all P >0.05). The serum albumin (ALB), prealbumin (PA), lymphocyte (LYM), lymphocyte percentage(LYM%), hemoglobin(HB), transferrin(TRF), total protein(TP) in the death group were significantly lower than those in the survival group ( t =5.884, 5.826, 2.020, 5.665, 4.726, 4.935, 2.862;all P <0.05). The number of patients receiving nutritional guidance in the death group was significantly less than that in the survival group ( χ 2 =12.597, P = 0.000). There were no significant difference on white blood cell(WBC) and red blood cell(RBC) between two groups. Multivariate logistic regression analysis showed that old age, male and not receiving significant nutritional guidance were independent risk factors for 1 year mortality of elderly patients with hip fracture ( OR =1.309, 43.548, 6.032;all P <0.05);high serum ALB, PA, HB, LYM% levels and combined with two or less basic diseases were protective factors ( OR =0.958, 0. 913, 0.985, 0.954, 0.832; all P <0.05)., Conclusion: Advanced age, male and multiple underlying diseases were independent risk factors for 1-year mortality in elderly patients with hip fracture, while higher preoperative nutritional level and routine nutritional guidance were protective factors.

Objective: To investigate the activation and its role of bone morphogenetic protein 2 (BMP2)/Smad1/Runt-related transcription factor 2 (Runx2) signal pathway in renal artery of rat models with vascular calcification., Methods: Twenty four male SD rats were randomly divided into control group and calcification group. Rat vascular calcification model was constructed by administration of vitamin D3 plus nicotine. Vascular calcification was confirmed by Von Kossa staining and calcium content was detected by calcium assay. Real time-PCR was applied to detect the expression of BMP2, Smad1, Runx2 mRNA, and immunohistochemistry was used to measure the protein levels of BMP2, Smad1, Runx2, α-smooth muscle actin (α-SMA)., Results: Von Kossa staining showed a large number of black granules deposited in renal artery. Calcium content in calcification group was significantly higher than that in normal group. Compared with the control group, the expressions of BMP2, Smad1 and Runx2 mRNA in renal artery were increased in calcification group. The protein levels of BMP2, Smad1 and Runx2 were higher while the expression of α-SMA was lower in calcification group than those in control group. The correlation analysis was found a positivie correlation between the calcium content and BMP2 mRNA (r = 0.655, P < 0.05), Smad1 mRNA (r = 0.735, P < 0.05), Runx2 mRNA (r = 0.734, P < 0.05)., Conclusion: The expression of BMP2/Smad1/Runx2 signal pathway was strongly correlated with the severity of vascular calcification, which may be involved in the occurrence and development of vascular calcification.

The hydrophilicity of the normal decoction pieces (NDP) of Indigo Naturalis is not good, therefore, it is not suit for decoctions. In this paper, powder modification technology is used and some NDP and alcohol are ground together in the vibromill to prepare the hydrophilic decoction pieces (HDP) of Indigo Naturalis. Initially, the properties of NDP, ultrafine decoction pieces (UDP) and HDP are compared, the hydrophilicity of UDP was promoted slightly, that of HDP is promoted dramatically. Then, three batches of Indigo Naturalis are prepared to HDP separately, but there is no obvious difference in the contact angle. Furthermore, the size distribution, surface area and micro-shape of HDP are bigger than that of UDP and smaller than NDP. The contents of indigo and indirubin in three decoction pieces are the same, as well as the species of inorganic substance, although there is a little difference in the proportion of five inorganic substances. The fact suggests the change of physical state and the qualitative and quantitative change of organism and inorganic substances are not the main factors to influence the hydrophilicity. In addition, hydroxyl, methylene and methyl can be identified at the wavenumber of 3 356 cm(-1) and 1 461 cm(-1) in infrared spectrum; the content of alcohol in HDP is 0.67% measured by gas chromatogram. The stability of HDP in the heating condition is studied, the fact suggests the hydrophilic effect of HDP at 40 degrees C is relatively stable. All above research suggests that the alcohol is the main factor to influence the hydrophilicity and maybe the intermolecular force which fixed alcohol molecule on the surface of Indigo Naturalis is the basic principle to produce the hydrophilicity.

Objective: To evaluate clinical value of denaturing high performance liquid chromatography (DHPLC) used in detecting transforming growth factor beta receptor 3 (TGFBR-3) exons 11 and 12 polymorphism in women with idiopathic premature ovarian failure (POF)., Methods: From Feb. 2009 to Dec. 2011, 110 patients with idiopathic POF undergoing treatment at Shenzhen Maternal & Child Health Institute affiliated to Southern Medical University were enrolled as POF group in this study. In the mean time, 110 women under 40 years old with normal hormonal level and menstrual cycles as control group. The exons 11 and 12 of TGFBR-3 gene polymorphism were screened by using DHPLC, and results of DNA sequencing was as golden standard. Some related indexes were calculated, such as sensitivity, specificity, false negative value, false positive value, Youden index, positive predictive value, and negative predictive value. At the same time, 20% of the tested specimens were chosen randomly and detected by DHPLC again. The value of Kappa index were calculated by comparing the results between the first and second DHPLC analysis., Results: The exon 11 of TGFBR-3 were not identified gene polymorphism and two nucleotide polymorphisms were identified in exon 12. For 2022 T/C polymorphism, the frequencies of CC with 0.9% (1/110), TC with 22.7% (25/110), TT with 76.4% (84/110), C with 12.3% (27/220) and T with 87.7% (193/220) in POF group were significantly different from CC with 0, TC with 9.1% (10/110) and TT with 90.9% (100/110), C with 4.5% (10/220) and T with 95.5% (210/220) in control group (all P<0.05). Allelic and genotypic frequencies of 2161-75 C/T were not differed significantly between the two groups (all P>0.05). As DNA sequencing as golden standard, DHPLC showed that the sensitivity was 100%, specificity was 97.9%, Youden index was 97.9%, positive predictive value was 96.3%, negative predictive value was 100%, and Kappa index was 0.888 (P<0.05)., Conclusion: DHPLC analysis is higher validity, reliability and practicability method in detecting TGFBR-3 polymorphism in idiopathic premature ovarian failure.

Objective: To study the micromeritic properties of different particle size of Scutellaria baicalensis and provide a basis for being directly used or as raw material of Chinese herba preparation., Methods: Size distribution, surface area and pore volume, contact angle, angle of repose and bulk density, moisture absorption, micromorphology, Infrared spectrum, HPLC fingerprint were used to evaluate the differences of micromeritic properties of 4 kinds of Scutellaria baicalensis superfine grinding., Results: With the particle size of powders decreased, size distribution and bulk density decreased, the surface area and pore volume, contact angle and moisture absorption increased, angle of repose first increased and then decreased. Infrared spectrum and HPLC fingerprint showed no change of chemical composition of Scutellaria baicalensis., Conclusion: Different particle size of Scutellaria baicalensis leads to the differences of micromeritic properties. Superfine grinding III is determined as a better particle size.

Objective: To prepare dental ulcer powder by using particle design technology, and compare the effect on the micromeritic property of dental ulcer powder with regular grinding and ultrafine grinding methods., Method: Above three methods were respectively used to make dental ulcer powder, in order to evaluate their difference in appearance character, grain size distribution, specific surface area and porosity, contact angle, micro-morphological character and borneol's stability., Result: Compared with normal powder, ultrafine powder and particle design showed increase in color uniformity and decrease in sour taste, and the particle design powder smells almost no borneol. Their grain size distributions were significantly less that of normal powder (P < 0.01), with the same grain size distribution in ultrafine powder and particle design powder. Their specific surface areas and porosities were significantly more than that of normal powder (P < 0.01), with the highest figures in ultrafine powder. Their contact angles were significantly more than that of normal powder (P < 0.01), with the highest figure in particle design powder. The surface of normal powder was smooth, with a few of small particle adhered. The surface of ultrafine powder was partially coated with small particles, where as the surface of particle design powder was mostly coated with particles. There was difference in micro-morphological character and surface attachment among the three. The 10-day accelerate stability experiment showed that normal power, ultrafine powder and particle design powder lost borneol by 90. 13% , 66. 48% and 40.57%, respectively. Particle design powder showed the highest stability, followed by ultrafine powder and normal powder., Conclusion: The preparation process can affect the micromeritic properties, by changing microscopic structure of the powders. We can design the macroscopic property of powder by regulating the formation of the microscopic structure with particle design technology.

Objective: To summarize the clinical features of idiopathic premature ovarian failure (POF) and explore the early diagnosis and intervention., Methods: A retrospective study was conducted in 39 women with idiopathic POF treated between February, 2009 and January, 2010. The clinical data of the patients including the menstrual feature, POF incidence, vaginal ultrasound and pregnancy outcomes were investigated., Results: One patient had primary amenorrhea and 38 had secondary amenorrhea with an average duration of amenorrhea of 5.82 years. Abrupt cessation occurred after 1-2 menstruations following the menarche in 2 cases (5.1%) and without identifiable preceding signs in 9 cases (23%). The mean uterine and ovarian volume was significantly smaller in POF group than in the control group. Antral follicle count (AFC) was also significantly lower in POF group. Vaginal ultrasound detected at least one ovary in 89.7% and follicular activity in 79.5% of the POF patients. Evidence of ovulation was found in 12 patients, and spontaneous pregnancy occurred in 2 patients with a pregnancy rate of 5.1%., Conclusion: Patients with menstrual disturbance, polymenorrhea and oligomenorrhea are at risk of developing POF, in which case regular detection of the mean uterine volume, ovarian volume and AFC by vaginal ultrasound may help in early POF detection. Close monitoring can be necessary in the course of hormone replacement therapy, and timely intervention with assisted reproductive techniques may increase the chance of pregnancy.

Objective: To explore the best waist circumference (WC) cut-point for identifying cardiovascular risk factors among adolescents., Methods: Human basic parameters were measured among 3986 adolescents aged 14 - 18 in Qinhuangdao. Receiver operator characteristic curve (ROC) analysis was employed to determine the optimal WC cut-point for detecting cardiovascular risk factors., Results: The prevalence of the clustering of cardiovascular risk factors significantly increased after the WC was >or= 80th percentiles (77.0 - 79.0 cm for the boys and 70.0 - 72.5 cm for the girls). The age standardization detection rate was 24.9% in boys and 9.9% in girls. ROC analysis showed that the optimal WC cut-point was 80th percentiles, with the sensitivity of 84.3% and specificity of 85.9% in boys, and with sensitivity of 90.7% and specificity of 83.2% in girls., Conclusion: There is a significant correlation between WC and cardiovascular risk factors. The optimal WC cut-point for predicting the clustering of cardiovascular risk factors is the 80th percentile.

Objective: Based on 'Back-tracking' method, identification and quality evaluation of complex traditional Chinese medicine (TCM) preparation of Baoji pills (BJP) were carried out by HPLC fingerprint analysis., Method: HPLC-DAD fingerprint of BJP was conducted with Zorbax SB-C18 column and non-linear elution with the mobile phase consisted of acetonitrile-0.5% glacial acetic acid at column temperature 30 degrees C and detective wavelengths of 250 nm and 283 nm. From the established chromatographic pattern of BJP, track backward to the corresponding crude herbal drugs in the formula, attribution ofmost peaks in the BJP fingerprint can be disclosed., Result: The BJP HPLC fingerprint consisted of 44 peaks among which 35 peaks were assigned by parallel comparison with the fingerprint of the 10 corresponding crude drugs in the formula such as pueraria, pummelo peel, and magnolia bark, etc. and 22 peaks we reidentified by comparison with the chemical reference substances., Conclusion: The established HPLC fingerprint represents the whole character of BJP, which enhanced the specialty for control and assessment of the product quality. It exemplified much more effective for quality control than selecting any marker for qualitative or quantitative testing target. And the Back-tracking' experimental method extended the study mentality for complex formula TCM products chromatographic fingerprinting analysis.

Dermal defection and the degree of its loss determine the natural process of wound healing, which is the key reason leading to excess scar hyperplasia. The function of tri-dimensional structure in dermis acts as a template to regulate the properties of reparative cells. The template structure induces the reparative cells to grow into the structure which changes the skin mechanic status on wound area. Also, the component of extracellular matrix can affect behaviours of fibroblasts negatively or positively, for the reason that the structure of dermal tissue has a permissive effect on the dermal components in regulating behaviours of reparative cells. Therefore, the behaviors of cells depend on the structure of the template. The suitable tri-dimensional structure of dermis facilitates normal cell cycling. The more the structure of dermis closed to its physiological status, the better the biological behaviors of cells act. Moreover, the integrity as well as the continuity of dermal tissue is the prerequisite for serving as a template. The damage to the integrity and the continuity of dermal tissue may be one of the key reasons to lead abnormal tissue repair and scar formation. Thus, we hypothesize that the loss of dermal template may be one of the mechanism of abnormal scar formation and propose the theory of extracellular matrix framework deficiency or destruction.

Objective: To discuss the clinical feature, diagnosis and treatment options of adolescent endometriosis., Methods: The records of adolescent patients with endometriosis (11-20 years old) who were admitted to First, Second and Third Affiliated Hospital of Zhongshan University and Guangdong Provincial People's Hospital between 1990 and 2003 were retrospectively reviewed., Results: Forty-three patients were diagnosed as endometriosis either by laparotomy or laparoscopy. The chief symptoms leading to the diagnosis were palpable pelvic mass (18/43), dysmenorrhea (15/43), chronic pelvic mass (10/43) and acute pelvic pain (4/43). The majority of patients (53%) presented with the revised AFS-r classification stage III, 8 cases (19%) presented with stage I, 3 cases (7%) with stage II and 9 cases (21%) with stage IV. Nine cases (21%) had complicated genital tract abnormalities. Conservative operations, including salpingo-oophorectomy ins cases, ovarian cystectomy in 31 cases and laparoscopic vaporization in 8 cases, were performed. Surgeries were followed by hormonal suppression using oral contraceptives in a continuous or cyclic manner., Conclusions: Adolescent endometriosis may occur around 4.6 years after menarche. The chief symptoms are palpable pelvic mass and dysmenorrhea. The treatment of endometriosis in adolescence does not differ principally from that in adult women. In the treatment of endometriosis and for the prevention of recurrence, it is recommended to give 3-6 months of oral contraceptives.

Objective: To develop the quality control standard of Zhishidaozhi Tabloid Pills., Method: Applying TLC to identify Radix et Rhizoma Rhei, Fructus Aurantii Immaturus, Rhizoma Coptidis, Radix Scutellariae, and HPLC to determine the content of emodin of Radix et Rhizoma Rhei., Result: Radix et Rhizoma Rhei, Fructus Aurantii Immaturus, Rhizoma Coptidis and Radix Scutellariae could be indentified by TLC. Emodin showed a good linear relationship at a rang of 0.0612-0.612 microgram, r = 0.9999. The average recovery was 97.9%, and RSD was 2.1%., Conclusion: The methods are accurate and quick, and can be used for the quality control of Zhishidaozhi Tabloid Pills.