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Integrity of the pancreatic duct-acinar system in the pathogenesis of acute pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2010年第3期9卷 242-247页

作者： wang, guo-jun Li, Yuan Zhou, Zong-Guang wang, Cun Meng, Wen-Jian Sichuan Univ W China Hosp Inst Digest Surg Chengdu 610041 Peoples R China Sichuan Univ W China Hosp Dept Gen Surg Chengdu 610041 Peoples R China

BACKGROUND: Acute pancreatitis is an acute inflammatory process of the pancreas that frequently involves peripancreatic tissues and at times remote organ systems. For a long time, the etiology and pathogenesis of acute pancreatitis has been intensively investigated worldwide, but the pathogenetic theories are controversial. The integrity of the pancreatic duct-acinar system might play an important role in the pathogenesis of this disease. DATA SOURCES: Web of Science and PubMed databases were searched for published studies (between January 1966 and june 2009) to identify relevant articles using the keywords 'acinar hyperstimulation', 'pathogenesis', 'acute pancreatitis', 'pancreatic duct-acinar system', and 'pancreatic duct pressure'. Most of the relevant articles were reviewed. RESULTS: From critical reading of the relevant articles, we found that the underlying mechanisms involved in the pathogenesis of acute pancreatitis are still under debate and ill-understood. On the basis of the relevant studies, we propose a hypothesis for the pathogenesis of acute pancreatitis, in which the integrity of the pancreatic duct-acinar system plays an essential role in the onset and progression of various forms of the disease. CONCLUSIONS: In our hypothesis, pancreatic duct obstruction and hyperstimulation of the exocrine pancreas are preconditions for the onset of acute pancreatitis; under the common conditions of pancreatic duct obstruction and acinar hyperstimulation, acute pancreatitis arises and develops. This may be an important common pathophysiological mechanism causing various forms of acute pancreatitis. (Hepntobiliary Pancreat Dis Int 2010; 9: 242-247)

关键词： pancreatic duct-acinar system pathogenesis acute pancreatitis acinar hyperstimulation pancreatic duct pressure

Effects of B on the Microstructure and Oxidation Resistance of Nb-Ti-Si-based Ultrahigh-temperature Alloy

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Chinese Journal of Aeronautics 2009年第5期22卷 544-550页

作者： wang jun guo Xiping guo Jinming State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi 'an 710072 China

Nb-Ti-Si-based ultrahigh-temperature alloys concocted with boron ranging from 0 to 2 at% are prepared by arc-melting technology. The effects of adding boron on their as-melted microstructure and oxidation resistance are analyzed. The （Nb,Ti）ss, β-（Nb,Ti）5Si3 and γ-（Nb,Ti）5Si3 exist in Nb-22Ti-16Si-6Cr-3Al-4Hf alloy, while （Nb,Ti）ss, α-（Nb,Ti）5Si3 and γ-（Nb,Ti）5Si3 are present in Nb-22Ti-16Si-6Cr-3Al-4Hf-lB and Nb-22Ti-16Si-6Cr-3Al-4Hf-2B alloys. The oxidation of Nb-Ti-Si-based ultrahigh-temperature alloys is dominated by the diffusion of oxygen through （Nb,Ti）ss. Compared to boron-free alloys, the boron-containing alloys have significantly lower oxidation rate when oxidized at 1 200 ℃ for less than 50 h, but, for more than 50 h, their oxidation resistance deteriorates.

关键词： oxidation resistance constituent phase oxidation kinetics ultrahigh-temperature alloy arc-melting

Ultrasonic Degradation of Methyl Orange in Presence of Y2O3 Doping Anatase TiO2 Catalyst

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Journal of Rare Earths 2004年第Z1期22卷 160-164页

作者： wang jun guo Baodong Pan Zhijun Liu Zhenrong Wen Fuyu Zhang Zhaohong Department of Chemistry Liaoning University Shenyang 110036 China Department of Chemistry Liaoning University Shenyang 110036 China Department of Chemistry Liaoning University Shenyang 110036 China Department of Chemistry Liaoning University Shenyang 110036 China Department of Chemistry Liaoning University Shenyang 110036 China Department of Chemistry Liaoning University Shenyang 110036 China

Various affecting factors and degradation mechanism were studied on ultrasonic degradation of methyl orange adopting Y2O3 doping anatase TiO2 catalyst prepared in *** the experiment, the UV-VIS spectrophotometer was used to follow and inspect the degradation process of methyl *** results indicate that the ultrasonic degradation ratios of methyl orange in the presence of anatase TiO2 catalyst are much better than those without ***, the catalytic performance of Y2O3 doping anatase TiO2 catalyst is obviously higher than that of anatase TiO2 catalyst without *** optimal conditions were adopted in this work and the degradation and COD elimination ratio of methyl orange got to98% and 99.0% in 90 min, respectively.

关键词： Y2O3 doping anatase TiO2 catalyst ultrasonic degradation methyl orange rare earths

3DFD Simulation of Asymmetric Wave Field by Side-wall Acoustic Tool in Open and Cased Wells

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Petroleum Science 2006年第2期3卷 47-52页

作者： Tao guo He Fengjiang wang Bing guo jun Well Logging Key Laboratory of CNPC China University of Petroleum Beijing 102249 China

We developed a parallelized scheme of 3D finite difference （3DFD）with non-oniform staggered grid to simulate the eccentric borehole acoustic field with side-wall acoustic logging tools in open and cased wells. Higher accuracy and lower computation cost were achieved with this scheme for modeling such an asymmetric wave field generated by a high frequency source near or on the borehole wall. We also modeled the cases with and without considering the effects of the tool body. The simulation results demonstrated that the logging tool body would attenuate the direct waves but have only little influence on the interface waves in such a borehole condition. The effects of the tool body on the wave field were significant only when the contrast of the elastic properties between tool body and borehole fluid was large.

关键词： Borehole acoustic logging eccentric acoustic field 3D FD non-uniform staggered grid OpenMp PML

Can the inner gap sparking take place in millisecond pulsars?

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Chinese Journal of Astronomy and Astrophysics 2003年第5期3卷 443-452页

作者： Hong-Guang wang, guo-jun Qiao and Ren-Xin XuDepartment of Astronomy, Peking University, Beijing 100871 Department of Astronomy Peking University Beijing 100871

The inner vacuum gap model has become the foundation stone of most theorieson pulsar radio emission. The fundamental picture of this model is the sparking, which wasconjectured to be induced by magnetic absorption of background gamma photons. However, a questionis, can the sparking be triggered in the millisecond pulsars (MSPs) with magnetic fields (B) onlyabout 10~8 G? We investigate this problem by including the pair production above the inner *** the assumption that the magnetic field is dipolar, our results show the background gamma-rayemission can not be the key factor that triggers the sparking, at least not in MSPs with B ～ 10~8G, if the temperature in the polar cap region is only so high as is observed (< 4 x 10~6K). Someother mechanisms are required.

关键词： pulsar: general gamma rays magnetic fields

How Fast Could a Proto-pulsar Rotate?

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Chinese Journal of Astronomy and Astrophysics 2002年第6期2卷 533-538页

作者： Ren-Xin Xu, Hong-Guang wang and guo-jun QiaoDepartment of Astronomy, School of Physics, Peking University, Beijing 100871 Department of Astronomy School of Physics Peking University Beijing 100871

According to two estimated relations between the initial period and the dynamo-generated magnetic dipole field of pulsars, we calculate the statistical distributions of pulsar initial periods. It is found that proto-pulsars are very likely to have rotation periods between 20 ms and 30 ms, and that most of the pulsars rotate initially at a period < 60 ms. Our result supports the asymmetric neutrino emission model for pulsar kick.

关键词： pulsars neutron stars magnetic fields

A Novel Flavonoid Glucoside from Anoectochilus roxburghii （Wall,） Lindl.

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Journal of Integrative Plant Biology 2006年第3期48卷 359-363页

作者： Chun-Nian He Chun-Lan wang Shun-Xing guo jun-Shan Yang Pei-Gen Xiao Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100094 China

Eight compounds were isolated from the ethyl acetate- and n-butanol-soluble fractions of the ethanollc extract of the whole plant of Anoectochllus roxburghll（Wali.） Lindi. （Orchidaceee）. On the basis of spectroscopic methods, the structures of these compounds were elucidated as quercetin-7-O-β-D-[6＂-O-（trans-feruloyi）]- giucopyranosids （compound 1）, 8-C-p-HydroxybenzyiquerceUn （compound 2）, isorhamnetin-7-O-β-D- giucopyranoside （compound 3）, isorhamnetin-3-O-β-D-giucopyranoside （compound 4）, kaempferoi-3-O-β-D- giucopyranoside （compound 5）, kaempferoi-7-O-β-D-giucopyranoside （compound 6）, 5-hydroxy-3＇,4＇,7- trimethoxyfiavonoi-3-O-β-D-rutinoside （compound 7）, and isorhamnetin-3-O-β-D-rutinoside （compound 8）. Of the compounds isoisted, compound 1 was a new flavonoid giucoside and exhibited strong scavenging activity against the 1,1-diphenyi-2-picryihydrazyi free radical, whereas the ethanolic extract showed weak activity. Compounds 2-8 were obtained from this family for the first time.

关键词： Anoectochilus roxburghii quercetin-7-O-β-D-[6"-O-(trans-feruloyl)]-glucopyranoside radical-scavenging activity.

NuMED CHEATHAM-PLATINUM STENT AND BALLOON IN BALLOON DELIVERY CATHETER FOR TREATMENT OF NATIVE COARCTATION OF THE AORTA

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Chinese Medical Sciences Journal 2006年第1期21卷 65-67页

作者： Guang-yi wang Bo Yang Zhi-feng wang jun guo Lu-yue Gai Guang Zhi Department of Cardiology General Hospital of People＇s Liberation Army Beijing 100853

COARCTATION of the aorta (CoA) is a congenital heart defect involving a narrowing of the *** narrowed segment called coarctation is most likely to happen in the segment just after the aortic *** narrowing can be removed by surgery or sometimes by a nonsurgical balloon ***, aortic coarctation may recur even after successful surgery or balloon ***, coarctation can now be treated with nonsurgical balloon dilation associated with implanting a stent using cardiac *** we reported our experience in a 19-year-old boy with CoA who underwent successful covered Cheatham-Platinum (CP) stent implantation for the coarctation.

关键词： covered stent coarctation of the aorta catheter intervention

Dicamba and Sugar Effects on Callus Induction and Plant Regeneration from Mature Embryo Culture of Wheat

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Agricultural Sciences in China 2010年第1期9卷 31-37页

作者： REN Jiang-ping,wang Xin-guo and YIN jun National Engineering Research Center for Wheat/Henan Agricultural University,Zhengzhou 450002,P.R.China National Engineering Research Center for Wheat/Henan Agricultural University Zhengzhou 450002 P.R. China

To establish a highly efficient plant regeneration system for wheat genetic transformation, the effects of three different concentrations of dicamba and two different sugar types on callus induction and plant regeneration from mature embryo cultures were evaluated. Callus induction and plant regeneration were obtained from mature embryos of two commercial cultivars Zhoumai 18 and Yumai 34 （Triticum aestivum L.） cultured on L3 basal medium. The results showed that the efficiency of mature embryo culture was significantly influenced by the genotypes, sugar types and dicamba concentrations. 4 mg L^-1 dicamba proved the best effective for inducing embryogenic callus and also gave the highest proportion of plants regenerated across the two cultivars. Substitution of maltose by sucrose significantly improved the plant regeneration efficiency in both cultivars. There was a significant interaction between genotype-by-sugar types, and sugar types-bydicamba concentrations. Overall, Zhoumai 18 gave the highest frequency of plant regeneration （82.65%） when dicamba concentration was 4.0 mg L^-1 and with sucrose in initial callus induction. These results will facilitate genetic transformation work with elite wheat.

关键词： wheat mature embryo tissue culture plant regeneration