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Albumin resuscitation protects against traumatic/hemorrhagic shock-induced lung apoptosis in rats

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第11期9卷 871-878页

作者： Yun zhang Zhong-yan LIANG shao-yang zhang Fang-fang HUANG Wei WU Yuan GAO Zuo-bing CHEN Department of Emergency Surgery the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Department of Intensive Care Unit the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Institute of lnfectious Diseases the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective: To determine the effects of albumin administration on lung injury and apoptosis in traumatic/hemorrhagic shock (T/HS) rats. Methods: Studies were performed on an in vivo model of spontaneously breathing rats with induced T/HS; the rats were subjected to femur fracture, ischemia for 30 min, and reperfusion for 20 min with Ringer's lactate solution (RS) or 5% (w/v) albumin (ALB), and the left lower lobes of the lungs were resected. Results: Albumin administered during reperfusion markedly attenuated injury of the lung and decreased the concentration of lactic acid and the number of in situ TdT-mediated dUTP nick-end labelling (TUNEL)-positive cells. Moreover, immunohistochemistry performed 24 h after reperfusion revealed increases in the level of nuclear factor κB (NF-κB), and phosphorylated p38 mitogen-activated protein kinase (MAPK) in the albumin-untreated group was down-regulated by albumin treatment when compared with the sham rats. Conclusion: Resuscitation with albumin attenuates tissue injury and inhibits T/HS-induced apoptosis in the lung via the p38 MAPK signal transduction pathway that functions to stimulate the activation of NF-κB.

关键词： Traumatic/hemorrhagic shock (T/HS) Mitogen-activated protein kinase (MAPK) Nuclear factor κB (NF-κB) Albumin Apoptosis

Impact of misplaced subclavian vein catheter into jugular vein on transpulmonary thermodilution measurement variables

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2016年第1期17卷 60-66页

作者： Wen-qiao YU Yun zhang shao-yang zhang Zhong-yan LIANG Shui-qiao FU Jia XU Ting-bo LIANG Department of Hepatobiliary and Pancreatic Surgery and Intensive Care Unit the Second Affiliated HospitalSchool of MedicineZhejiang University Hangzhou 310021 China Women's Hospital School of MedicineZhejiang University Hangzhou 310006 China Department of Emergency the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective： The subclavian vein （SCV） is usually used to inject the indicator of cold saline for a transpul- monary thermodilution （TPTD） measurement. The SCV catheter being misplaced into the internal jugular （IJV） vein is a common occurrence. The present study explores the influence of a misplaced SCV catheter on TPTD variables. Methods： Thirteen severe acute pancreatitis （SAP） patients with malposition of the SCV catheter were enrolled in this study. TPTD variables including cardiac index （CI）, global end-diastolic volume index （GEDVI）, intrathoracic blood volume index （ITBVI）, and extravascular lung water index （EVLWl） were obtained after injection of cold saline via the misplaced SCV catheter. Then, the misplaced SCV catheter was removed and IJV access was constructed for a further set of TPTD variables. Comparisons were made between the TPTD results measured through the IJV and mis- placed SCV accesses. Results： A total of 104 measurements were made from TPTD curves after injection of cold saline via the IJV and misplaced SCV accesses. Bland-Altman analysis demonstrated an overestimation of ＋111.40 ml/m2 （limits of agreement： 6.13 and 216.70 ml/m2） for GEDVI and ITBVI after a misplaced SCV injection. There were no significant influences on CI and EVLWI. The biases of ＋0.17 L/（min.m2） for CI and ＋0.17 ml/kg for EVLWI were re- vealed by Bland-Altman analysis. Conclusions： The malposition of an SCV catheter does influence the accuracy of TPTD variables, especially GEDVI and ITBVI. The position of the SCV catheter should be confirmed by chest X-ray in order to make good use of the TPTD measurements.

关键词： Transpulmonary thermodUution Jugular vein catheter Misplaced subclavian vein catheter Severe acutepancreatitis

Dexamethasone protects the glycocalyx on the kidney microvascular endothelium during severe acute pancreatitis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2019年第4期20卷 355-362页

作者： Wen-qiao YU shao-yang zhang Shui-qiao FU Qing-hui FU Wei-na LU Jian zhang Zhong-yan LIANG Yun zhang Ting-bo LIANG Department of Hepatobiliary and Pancreatic Surgery and Intensive Care Unit the First Affiliated Hospital School of Medicine Zhejiang University Department of Surgical Intensive Care Unit the Second Affiliated Hospital School of Medicine Zhejiang University Department of Reproductive Medicine Women's Hospital School of Medicine Zhejiang University

Objective: This study demonstrated that dexamethasone(DEX) protects the endothelial glycocalyx from damage induced by the inflammatory stimulus tumor necrosis factor-α(TNF-α) during severe acute pancreatitis(SAP), and improves the renal microcirculation. Methods: Ninety mice were evenly divided into 3 groups(Sham, SAP, and SAP+DEX). The SAP mice model was established by ligature of pancreatic duct and intraperitoneal injection of cerulein. Renal perfusion and function, and morphological changes of the glycocalyx were evaluated by laser Doppler velocimetry, electron microscopy, and histopathology(hematoxylin and eosin(H&E) staining), respectively. Serum levels of syndecan-1 and TNF-α were assessed by enzyme-linked immunosorbent assay(ELISA). The proàtectiveì effects of dexamethasone on the glycocalyx and renal microcirculation were evaluated. Results: Significantly high levels of serum TNF-α were detected 3 h after the onset of SAP. These levels might induce degradation of the glycocalyx and kidney hypoperfusion, resulting in kidney microcirculation dysfunction. The application of dexamethasone reduced the degradation of the glycocalyx and improved perfusion of kidney. Conclusions: Dexamethasone protects the endothelial glycocalyx from inflammatory degradation possibly initiated by TNF-α during SAP. This is might be a significant discovery that helps to prevent tissue edema and hypoperfusion in the future.

关键词： Severe acute pancreatitis(SAP) Acute kidney injury(AKI) Glycocalyx Dexamethasone Tumor necrosis factor-α(TNF-α)

The Influence of Deposition Temperature on the Epitaxial Growth of La_(0.7)Ca_(0.3)MnO_3 Thin Film

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北京印刷学院学报 2011年第4期19卷 72-75页

作者： yang shao-bo,zhang Ao(Beijing Institute of Graphic Communication,Beijing 102600,China)

The growth conditions of La0.7Ca0.3MnO3(LCMO) epitaxial thin film are *** results indicate that the deposition temperature plays a crucial role on the growth mode of LCMO thin *** is an optimal deposition temperature,To,for the epitaxial growth of LCMO thin *** only at the To,the real epitaxial LCMO thin film can be *** the deposition temperature deviates from the To,the thin film tends to be polycrystalline,although it orientes growth along a certain direction(a or c axis).Moreover,the experimental results show that just only for the epitaxial thin film the ferromagnetic-paramagnetic transition temperature(*** Courier temperature Tc) equals to the metal-semiconductor transition temperature(Tp).The ferromagnetic state shows metallicity and the paramagnetic state exhibits semiconducting character.

关键词： epitaxial polycrystalline thin film electric and magnetic phase transition

白内障术后晶状体前囊膜收缩对人工晶状体偏心的影响

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国际眼科杂志 2019年第9期19卷 1583-1585页

作者：张绍阳李莉广西壮族自治区人民医院眼科

目的:评价白内障术后晶状体前囊膜收缩对人工晶状体偏心的影响。方法:选取40例40眼年龄相关性白内障患者行白内障超声乳化吸除联合人工晶状体植入术,术后使用Photoshop软件测量术后3mo内的晶状体前囊膜口面积,使用iTrace视觉质量分析仪... 详细信息

目的:评价白内障术后晶状体前囊膜收缩对人工晶状体偏心的影响。方法:选取40例40眼年龄相关性白内障患者行白内障超声乳化吸除联合人工晶状体植入术,术后使用Photoshop软件测量术后3mo内的晶状体前囊膜口面积,使用iTrace视觉质量分析仪测量人工晶状体偏心距离,采用Pearson相关性分析晶状体前囊膜收缩对人工晶状体偏心的影响。结果:术后1d,1、3mo,前囊膜口面积逐渐缩小(P0.05),前囊膜口面积变化量与初始面积呈负相关(r=-0.476,P<0.05)。结论:白内障术后晶状体前囊膜的收缩可导致IOL偏心。

关键词：晶状体前囊膜收缩人工晶状体偏心

高质量分数Al_2O_3/Al复合材料的硬度和耐磨性能

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材料保护 2018年第4期51卷 47-50,140页

作者：杨绍斌张旭谢帅辽宁工程技术大学材料科学与工程学院辽宁阜新123000

现有的Al_2O_3颗粒增强铝基复合材料中的Al_2O_3质量分数低于10%,对于加入10%以上Al_2O_3的增强铝基复合材料的研究报道较少。以粉末冶金法制备了Al_2O_3(~40%)增强铝基复合材料,采用现代表面分析技术和ML-10型摩擦磨损试验机研究了这... 详细信息

现有的Al_2O_3颗粒增强铝基复合材料中的Al_2O_3质量分数低于10%,对于加入10%以上Al_2O_3的增强铝基复合材料的研究报道较少。以粉末冶金法制备了Al_2O_3(~40%)增强铝基复合材料,采用现代表面分析技术和ML-10型摩擦磨损试验机研究了这一复合材料的显微硬度和耐磨性。结果表明:在Al_2O_3粒度为10μm,质量分数为40%时,复合材料的显微硬度达到55.3 HV;在Al_2O_3粒度为10μm,质量分数为30%时,相对磨损最小值,为0.728%,空隙率也达到最小;复合材料中的Al_2O_3粒度和质量分数与紧密堆积理论要求的粒度和质量分数配比一致。

关键词：高质量分数Al2O3 铝基复合材料粉末冶金法显微硬度耐磨性

Microstructural evolution during the progressive transformation-induced plasticity effect in a Fe-0.1C-5Mnmedium manganese steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 369-379页

作者： Mei zhang Wenhao Li yangfei Chen yang Jiang Xiaofei Guo Han Dong School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China

The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile ***-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation *** findings were discussed with the local strain measurements via digital image *** results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of *** small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier *** volume fraction of RA gradually decreased from 26.8%to 8.2%prior to *** the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.

关键词： medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation

Ammonia pyrolysis oxidation excited by nanosecond pulsed discharge:Global/fluid models hybrid solution

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Journal of Energy Chemistry 2025年第1期100卷 385-396页

作者： Mingming zhang Hanyu Wu Qi Chen Jiaxin yang Bonan Liu School of Mechanical Electronic and Control Engineering Beijing Jiaotong University China University of Petroleum

The kinetic characteristics of plasma-assisted oxidative pyrolysis of ammonia are studied by using the global/fluid models hybrid solution ***,the stable products of plasma-assisted oxidative pyrolysis of ammonia are *** results show that the consumption of NH3/O2and the production of N2/H2change linearly with the increase of voltage,which indicates the decoupling of nonequilibrium molecular excitation and oxidative pyrolysis of ammonia at low ***,the detailed reaction kinetics mechanism of ammonia oxidative pyrolysis stimulated by a nanosecond pulse voltage at low pressure and room temperature is *** on the reaction path analysis,the simplified mechanism is *** detailed and simplified mechanism simulation results are compared with experimental data to verify the accuracy of the simplified ***,based on the simplified mechanism,the fluid model of ammonia oxidative pyrolysis stimulated by the nanosecond pulse plasma is established to study the pre-sheath/sheath behavior and the resultant consumption and formation of key *** results show that the generation,development,and propagation of the pre-sheath have a great influence on the formation and consumption of *** consumption of NH3by the cathode pre-sheath is greater than that by the anode pre-sheath,but the opposite is true for OH and O（1S）.However,within the sheath,almost all reactions do not ***,by changing the parameters of nanosecond pulse power supply voltage,it is found that the electron number density,electron current density,and applied peak voltages are not the direct reasons for the structural changes of the sheath and ***,the discharge interval has little effect on the sheath structure and gas mixture *** research results of this paper not only help to understand the kinetic promotion of non-equilibrium excitation in the process of oxidative pyrolysis but also help to explore th

关键词： Nanosecond pulsed discharge Ammonia Oxidative pyrolysis Fluid model Global model

基于简单线性迭代聚类超像素的meanshift跟踪

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应用光学 2017年第2期38卷 193-199页

作者：邵辰琳杨卫平张志龙国防科技大学电子科学与工程学院湖南长沙410073

为了增强目标跟踪算法在被跟踪目标发生运动位移、遮挡、形变、相似物体干扰等情况下的鲁棒性,提出利用超像素构建目标外观模型,将外观模型与候选区域进行匹配,获取候选区域当中目标超像素,并用Meanshift算法确定目标中心点的跟踪算法... 详细信息

为了增强目标跟踪算法在被跟踪目标发生运动位移、遮挡、形变、相似物体干扰等情况下的鲁棒性,提出利用超像素构建目标外观模型,将外观模型与候选区域进行匹配,获取候选区域当中目标超像素,并用Meanshift算法确定目标中心点的跟踪算法。仿真实验选取Benchmark库当中在运动位移、遮挡、形变、相似物体干扰方面具有代表性的视频Girl和FaceOcc1。该算法在视频Girl中的跟踪成功率和跟踪精度为0.601、0.856,比对比实验的经典算法当中跟踪效果最好的KCF算法的成功率和精度分别高0.059和0.084;在视频FaceOcc1中跟踪成功率和精度仅次于KCF。表明该跟踪算法在受到相似物体干扰和目标遮挡时具有良好的鲁棒性。

关键词：超像素颜色直方图 Meanshift算法外观模型跟踪