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Effect of the extrahepatic bile duct anatomy on choledocholithiasis and its clinical significance

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1363-1370页

作者： Zheng Cao Jia Zhou li Wei Hai-Yu he jun li Department of Gastroenterology The Second Affiliated Hospital of Kunming Medical UniversityKunming 650000Yunnan ProvinceChina

BACKGROUND A comprehensive understanding of the extrahepatic bile duct anatomy is vital to guide surgical procedures and perform endoscopic retrograde *** irregularities within the extrahepatic bile duct may increase susceptibility to bile duct *** To investigate the anatomical risk factors associated with extrahepatic bile ducts in patients diagnosed with choledocholithiasis,with a specific focus on preventing stone recurrence after surgical intervention and endoscopic *** We retrospectively analyzed the medical records of 124 patients without choledocholithiasis and 108 with confirmed choledocholithiasis who underwent magnetic resonance cholangiopancreatography examinations at our center between January 2022 and October *** regression analyses were conducted to identify the anatomical risk factors influencing the incidence of common bile duct *** Multivariate logistic regression analysis revealed that several factors independently contributed to choledocholithiasis *** independent risk factors for choledocholithiasis were diameter of the common hepatic[adjusted odds ratio(aOR)=1.43,95%confidence interval(CI):1.07-1.92,adjusted P value=0.016]and common bile(aOR=1.68,95%CI:1.27-2.23,adjusted P valuehe common hepatic duct(aOR=0.92,95%CI:0.84-0.99,adjusted P value=0.034),and angle of the common bile duct(aOR=0.92,95%CI:0.89–0.95,adjusted P valuehe anatomical features of the extrahepatic bile duct were directly associated with choledocholithiasis *** risk factors include an enlarged diameter of the common hepatic and bile ducts,a shorter length of the common hepatic duct,and a reduced angle of the common bile duct.

关键词： Bile ducts Extrahepatic Choledocholithiasis Cholangiopancreatography Magnetic resonance Cholangiopancreatography Endoscopic retrograde

C-reactive protein decreases interleukin-8 production in human endothelial progenitor cells by inhibition of p38 MAPK pathway

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Chinese Medical Journal 2009年第16期122卷 1922-1928页

作者： NAN Jing-long li Jian-jun he Jian-guo Department of Cardiology Fu Wai Hospital Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100037 China

Background C-reactive protein （CRP） has been reported to damage the vascular wall by inducing endothelial dysfunction and inflammation, and it is also speculated to have a role in attenuating angiogenic functions of human endothelial progenitor cells （EPCs）. Interleukin-8 （IL-8） is an important mediator of the paracrine mitogenic effect of EPCs which has direct angiogenic effects on mature endothelial cells. We, herein, investigated the direct effect of CRP on IL-8 production and gene expression in cultured human EPCs. Methods EPCs were isolated from the peripheral venous blood of healthy male volunteers. Cells were cultured in EndoCultTM liquid medium in the absence and presence of CRP at clinically relevant concentrations （5 to 25 μg/ml） for different durations （3 to 48 hours）. IL-8 protein and mRNA of cultured EPCs were evaluated using EliSA and real-time PCR. Results The results showed that CRP at a concentration of 10 μg/ml significantly reduced IL-8 secretion of cultured EPCs with a peak at 25 μg/ml, and also decreased mRNA expression in EPCs with a peak at 12 hours. In addition, preincubation of EPCs with SB203580, an inhibitor of p38 mitogen-activated protein kinase （MAPK） decreased CRP inhibition of IL-8 mRNA expression at 12 hours in EPCs. Conclusions Our study, for the first time, demonstrates that CRP directly inhibits EPCs IL-8 secretion, a key cytokine player of angiogenesis induced by EPCs. Inhibition occurred in part via an effect of CRP to active the p38 MAPK signal transduction pathway in EPC. The ability of CRP to inhibit EPCs IL-8 secretion may represent an important mechanism that further links inflammation to cardiovascular disease.

关键词： C-reactive protein endothelial progenitor cells interleukin-8

Changes in microstructure and properties of weld heat-affected zone of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第8期31卷 2041-2052页

作者： Shu-jun Jia Qi-lin Ma Yu Hou Ba li he-song Zhang Qing-you liu Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Collaborative Innovation Center for Steel Commonality University of Science and Technology BeijingBeijing 100083China Construction Project Management Branch of China National Petroleum Pipeline Network Group Co. Ltd.Langfang 065000HebeiChina

The evolution of the microstructure and toughness of APL5L X80 pipeline steel after thermal welding simulation was investigated by X-ray diffraction,electron backscatter diffraction,and transmission electron *** results indicated that primary heat-affected zones can be divided into weld,coarse-grained,fine-grained,intercritical,and sub-critical *** microstructure of the weld zone is mainly composed of bainitic ferrite and a small amount of granular bainite;however,the original austenite grains are distributed in the columnar *** structure of the coarse-grained zone is similar to that of the weld zone,but the original austenite grains are *** contrast,the microstructure in the fine-grained zone is dominated by fine granular bainite,and the effective grain size is only 8.15μm,thus providing the highest toughness in the entire heat-affected *** intercritical and subcritical zones were brittle valley regions,and the microstructure was dominated by granular ***,the martensite-austenite(M/A)constituents are present in island chains along the grain boundaries,and the coarse size of the M/A constituents seriously reduces the *** results of the crack propagation analyzes revealed that high-angle grain boundaries can significantly slow down crack growth and change the crack direction,thereby increasing the material *** impact toughness of the low-temperature tempering zone was equivalent to that of the columnar grain zone,and the impact toughness was between those of the critical and fine-grained zones.

关键词： Welding thermal simulation Impact toughness Crack propagation Martensite-austenite constituent High-strength low-alloy steel weld heat-affected zone

Observation of robust anisotropy in WS_(2)/BP heterostructures

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Nano Research 2024年第7期17卷 6749-6756页

作者： Xinran li Xing Xie Biao Wu junying Chen Shaofei li jun he Zongwen liu Jian-Tao Wang Yanping liu Institute of Quantum Physics School of PhysicsCentral South University932 South Lushan RoadChangsha 410083China State Key Laboratory of Precision Manufacturing for Extreme Service Performance Central South University932 South Lushan RoadChangsha 410083China School of Chemical and Biomolecular Engineering The University of SydneyNSW 2006Australia The University of Sydney Nano Institute The University of SydneyNSW 2006Australia Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China Shenzhen Research Institute of Central South University Shenzhen 518000China

Two-dimensional(2D)anisotropic materials have garnered significant attention in the realm of anisotropic optoelectronic devices due to their remarkable electrical,optical,thermal,and mechanical *** extensive research has delved into the optical and electrical characteristics of these materials,there remains a need for further exploration to identify novel materials and structures capable of fulfilling device requirements under various ***,we employ heterojunction interface engineering with black phosphorus(BP)to disrupt the C_(3) rotational symmetry of monolayer WS_(2).The resulting WS_(2)/BP heterostructure exhibits pronounced anisotropy in exciton emissions,with a measured anisotropic ratio of 1.84 for neutral *** a comprehensive analysis of magnetic-field-dependent and temperature-evolution photoluminescence spectra,we discern varying trends in the polarization ratio,notably observing a substantial anisotropy ratio of 1.94 at a temperature of 1.6 K and a magnetic field of 9 *** dynamic behavior is attributed to the susceptibility of the WS_(2)/BP heterostructure interface strain to fluctuations in magnetic fields and *** findings provide valuable insights into the design of anisotropic optoelectronic devices capable of adaptation to a range of magnetic fields and temperatures,thereby advancing the frontier of material-driven device engineering.

关键词： two-dimensional materials in-plane anisotropy black phosphorus heterojunctions optoelectronic devices photoluminescence spectra

Au nanoclusters anchored on TiO_(2) nanosheets for high-efficiency electroreduction of nitrate to ammonia

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Nano Research 2024年第3期17卷 1209-1216页

作者： Miaosen Yang Tianran Wei Jia he Qian liu ligang Feng Hongyi li jun Luo Xijun liu School of Chemical Engineering Northeast Electric Power UniversityJilin 132012China Nanchang Institute of Technology Nanchang 330044China State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830017China State Key Laboratory of Featured Metal Materials and life-cycle Safety for Composite Structures Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured MaterialsSchool of ResourcesEnvironment and MaterialsGuangxi UniversityNanning 530004China Institute for New Energy Materials and Low-Carbon Technologies School of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Institute for Advanced Study Chengdu UniversityChengdu 610106China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Guangzhou Panyu Polytechnic Guangzhou 511483China ShenSi Lab Shenzhen Institute for Advanced StudyUniversity of Electronic Science and Technology of ChinaLonghua DistrictShenzhen 518110China

Electrocatalytic nitrate reduction reaction(NO_(3)RR)offers a unique rationale for green NH_(3) synthesis,yet the lack of high-efficiency NO_(3)RR catalysts remains a great *** this work,we show that Au nanoclusters anchored on TiO_(2) nanosheets can efficiently catalyze the conversion of NO_(3)RR-to-NH_(3) under ambient conditions,achieving a maximal Faradic efficiency of 91%,a peak yield rate of 1923μg·h^(-1)·mgcat.-1,and high durability over 10 consecutive cycles,all of which are comparable to the recently reported metrics(including transition metal and noble metal-based catalysts)and exceed those of pristine TiO_(2).Moreover,a galvanic Zn-nitrate battery using the catalyst as the cathode was proposed,which shows a power density of 3.62 mW·cm^(-2) and a yield rate of 452μg·h^(-1)·mgcat.-*** simulations further indicate that the atomically dispersed Au clusters can promote the adsorption and activation of NO_(3)-species,and reduce the NO_(3)RR-to-NH_(3) barrier,thus leading to an accelerated cathodic *** work highlights the importance of metal clusters for the NH_(3) electrosynthesis and nitrate removal.

关键词： NH3 electrosynthesis Zn-nitrate battery Au nanoclusters nitrate reduction reaction(NRR) TiO_(2)nanosheets

Natural rubber latex as a potential additive for water-based drilling fluids

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Petroleum Science 2024年第4期21卷 2677-2687页

作者： jun Yang Guan-Cheng Jiang Jing-Tian Yi Yin-Bo he li-li Yang Teng-Fei Dong Guo-Shuai Wang College of Petroleum Engineering China University of Petroleum (Beijing) National Engineering Research Center of Oil & Gas Drilling and Completion Technology Changqing Drilling General Company CNPC Chuanqing Drilling Engineering Company Limited

The environmental hazards and "carbon footprint" of oil and gas drilling can be significantly reduced by replacing traditional petroleum-based chemical additives with natural materials derived from plants and animals. This paper explored for the first time the interaction mechanism between natural rubber latex(NRL) and bentonite suspensions(BTs) through a series of characterization experiments, as well as the potential applications in water-based drilling fluids(WBDF). The gel viscoelasticity experiments showed that NRL could decrease the consistency coefficient(k) and flow index(n) of BTs, and enhance the shear thinning performance of BTs as pseudo-plastic fluids. In addition, 0.5 w/v% NRL not only increased the critical yield stress and strengthened the structural strength between the bentonite particles, but also facilitated the compatibility of pressure loss and flow efficiency. The evaluation of colloidal stability and WBDF performance indicated that NRL particles could promote the hydration and charge stability on the surface of BTs particles, and optimize the particle size distribution and flow resistance of WBDF under the "intercalation-exfoliation-encapsulation" synergistic interaction. Moreover, NRL can improve the rheological properties of WBDF at high temperatures(ling the pores and cracks of the filter cake, which ultimately reduces the permeability of the cake and the filtration loss of WBDF.

关键词： Natural materials Water-based drilling fluids Natural rubber latex Bentonite suspensions Filtration loss

Separation of Ephedrines Using 1-Butyl-3-methylimidazolium-tetrafluoroborate Ionic liquids as Eluent in High-performance liquid Chromatography (HPLC)

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Chinese Chemical Letters 2003年第6期14卷 603-604页

作者： li jun he, Wen Zhu ZHANG, Bo WEN, Xia liU, Sheng Xiang JIANG* Lanzhou Institute of Chemical Physics, Chinese Academy of Science, Lanzhou 730000 Lanzhou Inst. of Chemical Physics Chinese Academy of Science Lanzhou 730000 China

A simple, effective HPLC method for separation of ephedrines was achieved by using 1-butyl-3-methylimidazolium-tetrafluoroborate ionic liquid solution (0.1% v/v) as eluent at pH 3.0. The involved mechanism may be due to that the imidazolium cations can effectively shield the silanol groups of alkylsilica surface, thereby decreasing band tailing and increasing the separation efficiency.

关键词： Ionic liquid ephedrine HPLC.

Advances in Mycobacterium siderophore-based drug discovery

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Acta Pharmaceutica Sinica B 2011年第1期1卷 8-13页

作者： jun-li he Jian-ping Xien Institute of Modern Biopharmaceuticals Southwest UniversityChongqing 400715China

Tuberculosis remains a public health threat of global *** is a scarce resource indispensable to both host and pathogen during infection with Mycobacterium tuberculosis,the causative agent of *** are critical molecules for iron acquisition under iron-limiting conditions and,as a very efficient pathogen,*** has evolved elaborate siderophores knowledge of which is being intensively translated into clinical *** paper summarizes the structures,types and physiological functions of Mycobacterium siderophores with emphasis on siderophore-inspired design of drugs and drug delivery vehicles.

关键词： Tuberculosis Mycobacterium tuberculosis Siderophore Drug vector Drug design

Effects of mid-passage gap with a variable surface angle on a turbine vane endwall’s aerothermal and film cooling performances

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Chinese Journal of Aeronautics 2024年第6期37卷 20-37页

作者： Zhiyu li Kaiyuan ZHANG Zhigang li jun li Institute of Turbomachinery Xi’an Jiaotong UniversityXi’an 710049China

The mid-passage gap is an inevitable structure in a vane passage due to turbine vanes being manufactured *** coolant from this gap is able to prevent hot mainstream ingression and provide cooling protection for the endwall.A novel idea of enlarging the endwall’s coverage area and reducing the endwall’s thermal load by applying the mid-passage gap with variable surface angles is carried out in this *** endwall’s aerothermal and film cooling performances under four mid-passage gap modes at three typical mass flow ratio conditions are numerically *** indicate that under the traditional mid-passage mode,the coolant flows into the mainstream with a perpendicular incidence angle and can’t stick to the ***,cooling failure occurs,and the endwall’s thermal load is badly *** film cooling level at the suction-side endwall is improved when applying the mid-passage gap of a 45surface angle due to the secondary vortex being *** addition,when applying the mid-passage gap of a 135surface angle,the horseshoe vortex is pushed away,and the coverage area at the pressure-side endwall is enlarged *** best film cooling performance is achieved when the upstream surface angle is 135and the downstream surface angle is 45due to the adiabatic film cooling effectiveness being increased at both the pressure-and suction-side *** the mass flow ratio is 1.5%,the coverage area is enlarged by 43%,and the area-averaged adiabatic film cooling effectiveness is increased by 37%,when compared with those under the traditional mid-passage mode.

关键词： Film cooling heat transfer Surface angle Mid-passagegap Turbinevane endwall