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Atomic oxygen reactions can contribute significantly to the oxidation of unsaturated aliphatic and aromatic hydrocarbons. The reaction mechanism is started by electrophilic O atom addition to the unsaturated bond(s) to form "chemically activated" triplet oxy-intermediate(s), which can evolve adiabatically on the triplet potential energy surface (PES) and nonadiabatically

The O(3P) + 1,3 C4H6 reaction is studied through non adiabatic AITSTME simulations and CMB experiments. The main reaction channels are HCO + C3H5, CO + C3H6, H2CO + C3H4, and H + C4H5O. Temperature dependent rates are then theoretically determined.

通过检索文献数据库中双环醇治疗酒精性肝病的随机对照试验，对1 149篇文献中9个随机对照试验，723例酒精性肝病患者的双环醇治疗酒精性肝病进行Meta分析，评价了双环醇治疗酒精性肝病的疗效和安全性。结果显示双环醇可显著改善酒精性肝病血清生物化学指标，具有较高安全性。.

Nanocomposites of Poly(butylene succinate) (PBS) and poly(∊-caprolactone) (PCL)-coated nano-TiO2 (C–TiO2) are prepared by melt-blending technique. The influence of high loading C–TiO2 on the microstructure, mechanical, thermal and dynamic rheological properties of pure PBS and its nanocomposites are studied. Scanning Electron Microscope results demonstrate that the surface modification and content of TiO2 are main factors to affect the microstructure of composites. Mechanical tests show that adding C–TiO2 into PBS matrix is an effective way to improve the impact strength of the PBS. Impact property and tensile property are sensitive to different microstructure, the former is distance between particles and the latter is the aggregation of particles. Dynamic rheological tests show that the incorporation of C–TiO2 particles into PBS can improve the elastic properties of PBS nanocomposites and restrict the mobility of PBS chains. Differential scanning calorimeter indicates the addition of C–TiO2 can increase the crystallization rate but do not influence the main PBS crystals. Depending on the state of composites, the C–TiO2 restricts or improves the mobility of PBS molecules.

To evaluate the diagnostic performance of bi-exponential modeling of intravoxel incoherent motion (IVIM) imaging for laryngeal and hypopharyngeal carcinoma.A total of 32 patients with pathologically proven laryngeal and hypopharyngeal squamous cell carcinoma were included in this study from November 2014 to August 2015.All patients underwent IVIM-DWI by using twelve b values (0, 10, 20, 30, 50, 70, 100, 150, 200, 400, 800 and 1 000 s/mm(2)). Using the IVIM approach, D, D(*) and f values were extracted using a bi-exponential fit.These quantitative parameters of primary carcinoma and normal pharyngeal tissue were compared.Statistical methods were used to assess differences between the tumor and normal pharyngeal tissue.There were no significant differences of D (P=0.903) and f (P=0.223) values observed among laryngeal carcinoma and hypopharyngeal carcinoma, and D(*) value was significantly different among the two groups (P=0.028). The values of D, D(*,) and f for primary carcinoma were (0.84±0.22)×10(-3) mm(2)/s, (65.71±19.66)×10(-3) mm(2)/s, and 45%±14%, respectively; for normal pharyngeal tissue were (1.48±1.04)×10(-3) mm(2)/s, (37.85±14.04)×10(-3) mm(2)/s, and 36%±12%, respectively (P=0.001, 0.000, and 0.006, respectively). Setting D value 0.949×10(-3) mm(2)/s was threshold to distinguish abnormal and normal tissues, the sensitivity, specificity and accuracy were 91.2%, 88.2% and 92.5%, respectively.There was no statistically significant difference of D and f values(both P0.05)in different pathological grades of primary carcinoma, and there was statistically significant difference in D(*) values found among the different pathological grades of primary carcinoma (P=0.001). There were statistically significant differences in D(*) values between the well differentiated group and the other two group (both P0.05), and there was no statistically significant difference between the moderately differentiated group and poorly differentiated group (P0.05).IVIM parameters can reflect the difference between laryngeal and hypopharyngeal carcinoma and normal pharyngeal tissue, and the D value has the best diagnostic performance.D(*) value in different pathological grades of laryngeal and hypopharyngeal squamous cell carcinoma is distinct, and it could reflect the pathological grade of tumor to some extent.

Under different reaction conditions, the expected and unexpected reaction products (of which X-ray crystallographic structure was presented) of etherification of 2-per(poly)fluoroethyl 4-substituted phenol with β-haloethanol can be obtained respectively.

To investigate the value of diffusion weighted imaging (DWI) in predicting the efficacy of preoperative chemoradiotherapy (CRT) for locally advanced rectal cancer.From 2007 to 2012, 86 patients with histopathologicaIly proven rectal cancer who underent pre-CRT were enrolled in this study prospectively. Diffusion-weighted MRl was performed in all patients before pre-CRT, while it was performed in part of the patients during and after pre-CRT as well.ADC values of the tumors were calculated on the workstation. Patients were assigned to the tumor downstaged group or the tumor nondownstaged group on the basis of T staging. The change in ADC following treatment and the difference in ADC between groups were analyzed.Of the 86 patients after surgery, 20 were diagnosed with T0, 2 with T1, 17 with T2, 44 with T3 and 3 with T4. 39 patients were classified as the downstaged group, of which 18 were of pCR. The remaining 47 patients were classified as the nondownstaged group. Of the total of 86 patients, the mean ADC values before, during, and after pre-CRT (pre-ADC, during-ADC, and post-ADC) were (1.03±0.17)×10(-3), (1.39±0.28)×10(-3), and (1.61±0.27)×10(-3) mm(2)/s and there was a significant difference (P0.001). However, the pre-CRT ADC of the downstaged group did not differ significantly from that of the nondownstaged group (P=0.615). Of the 43 patients who underwent MRI before, during and after pre-CRT, the mean ADC values were (1.05±0.16)×10(-3), (1.39±0.29)×10(-3)and (1.67±0.30)×10(-3) mm(2)/s, respectively, showing a significant difference (P0.001)as well.The mean ADC value of rectal cancer is gradually increasing along with the course of chemotherapy. Pre-ADC is not a good parameter to be used to predict the efficacy of pre-CRT for locally advanced rectal cancer.

The recent state-of-the-art of molecular-scale device systems utilizing self-assembled oligomers as the key fabrication strategy is discussed. A variety of devices have been demonstrated, including switches with inherent mechanisms significantly different from conventional solid state devices.

Presented here are several convergent synthetic routes to conjugated oligo(phenylene ethynylene)s. Some of these oligomers are free of functional groups, while others possess donor groups, acceptor groups, porphyrin interiors, and other heterocyclic interiors for various potential transmission and digital device applications. The syntheses of oligo(phenylene ethynylene)s with a variety of end groups for attachment to numerous metal probes and surfaces are presented. Some of the functionalized molecular systems showed linear, wire-like, current versus voltage (I(V)) responses, while others exhibited nonlinear I(V) curves for negative differential resistance (NDR) and molecular random access memory effects. Finally, the syntheses of functionalized oligomers are described that can form self-assembled monolayers on metallic electrodes that reduce the Schottky barriers. Information from the Schottky barrier studies can provide useful insight into molecular alligator clip optimizations for molecular electronics.

To duplicating the regulatory subunit p35Nck5a gene of mouse neuronal cdc2-like kinase in embryonic stem (ES) cells, about 12.2 kb of pGDTV vector for p35Nck5a gene duplication was constructed. The linearized pGDTV vectors were transfected into ES cells by electroporation. 245 drug-resistant cell clones were obtained in both G418 and GANC medium and the frequency of surviving cells was 6.22 x 10(-5). The ES cell clones were identified to have duplicated the p35Nck5a gene by use of both PCR and genomic Southern blotting, and the frequency of homologous recombination is 5.08 x 10(-7). The use of negative selection gene (HSV-tk) results in 7-fold increase at selection efficiency. This study lays the foundations of preparing mouse models of Alzheimer's disease.

This paper considers the effects of non-Newtonian lining-fluid viscosity, particularly shear thinning and yield stress, on the reopening of the airways. The airway was simulated by a very thin, circular polyethylene tube, which collapsed into a ribbonlike configuration. The non-Newtonian fluid viscosity was described by the powerlaw and Herschel-Buckley models. The speed of airway opening was determined under various opening pressures. These results were collapsed into dimensionless pressure-velocity relationships, based on an assumed shear rate γ˙ = U/(0.5 H), where U and H are the opening velocity and fluid film thickness, respectively. It was found that yield stress, like surface tension, increases the yield pressure and opening time. However, shear thinning reduces the opening time. An increased film thickness of the non-Newtonian lining fluid generally impedes airway reopening; a higher pressure is needed to initiate the airway reopening and a longer time is required to complete the opening process.

Two patients with unusual findings of renal angiomyolipoma (AML) were reported. One had intratumoral giant pseudoaneurysm with mural thrombus and hemorrhage, the other had intrarenal and perirenal hemorrhage, due to vascular malformation, rupture of small aneurysms and pseudoaneurysms within the tumor. Since imaging techniques such as CT, ultrasonography, MRI are being so commonly used, the detectability of renal AML is increased. Understanding of the various composition of renal AML and their accompanied pathology is most helpful in improving the accuracy of imaging diagnoses.

Five hybridomas stably secreting monoclonal antibodies (McAbs) to androstenedione were prepared by using artificially synthesized androstenedion-11 alpha-succinyl conjugate with bovine serum albumin (BSA) as antigen. These McAbs showed slightly high cross-reactivity with testosterone (8.1-12.3%) and estrone (0.8-2.5%) and high affinities ranging from 2.0 x 10(7) to 2.8 x 10(8) L/M. They were all of the IgG1 subclass. Xinjiang finewool ewes which were passively immunized with McAbs had higher circulating levels of progesterone (P) and luteinizing hormone (LH) than those of control ewes in two oestrous cycles and these changes led to increased ovulation rate and twin lambs born in young ewes.

Pelvic CT scans of 102 patients who underwent resection of rectosigmoid carcinoma are reviewed. Sixty one patients had abdominoperineal resection and 41 had abdominal resection and colostomy. Recurrent tumors developed in 31 patients (30.4%). The interval between surgery and tumor relapse ranged from 3 months to 108 months (median, 14 months). CT findings indicative of tumor recurrence included an eccentric, round or irregular presacral soft-tissue mass, 2-20 cm (16), marked enhancement after i.v. contrast administration (15), invasion of surrounding muscle and/or bone (4), six patients had perineal recurrent tumor which was eccentrically located and irregular in shape. Fifteen patients developed recurrent tumor after abdominal resection and colostomy. There were anastomotic recurrence (15), pari-anastomotic mass (5), regional metastatic adenopathy (6), ranging from 0.3 to 1.2 cm. Routine follow-up CT scan after rectosigmoid carcinoma resection is useful in depicting early recurrence and survival could be improved after salvage operation. Appropriate scanning techniques including air inflation of the remaining rectum and colon, i.v. contrast administration for enhancement of tumor mass and blood vessels are emphasized for improving the quality of CT images in order to differentiate recurrence or postoperative change, adenopathy or blood vessels. Enhancement of tumor mass and blood vessels are emphasized for improving the quality of CT images in order to differentiate recurrence or postoperative change, adenopathy or blood vessels.

Among 11,821 cases of esophageal carcinoma treated in a 32 year period, 7 were found to be associated with achalasia (0.059%). Five cases were proved by biopsy or cytology and 2 were diagnosed by esophagograms. There were 4 men and 3 women. The age ranged from 30-54 years with a median of 38. The age was younger than that of esophageal carcinoma unassociated with achalasia. Duration of achalasia was from 7 to 20 years. Three patients died within 1 year and 1 died 17 months after diagnosis. Three were lost to follow-up. The presenting symptoms were aggravating dysphagia in 4; and hoarseness, dyspnea and bloody regurgitation in the other two. Patients with achalasia should be treated energetically in the early stage. Double contrast esophagography and esophagoscopy should be done carefully during the followup. Preparation of the esophagus is most important when performing the X-ray examination of the esophagus.