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GdCl₃ abates hepatic ischemia-reperfusion injury by inhibiting apoptosis in rats

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Hepatobiliary & Pancreatic Diseases International 2009年第5期8卷 518-523页

作者： Jian-Yi Li xi gu Wen-Hai Zhang Shi Jia Yong Zhou Department of General Surgery Shengjing Hospital China Medical University Shenyang 110004 China.

BACKGROUND:Gadolinium chloride(GdCl3)is a specific inhibitor of Kupffer cells(KCs),which are important promoters of various liver *** is therefore of interest to explore the role of KCs in liver ischemia-reperfusion injury and their relations with apoptosis caused by ischemia-reperfusion injury. METHODS:One hundred male Wistar rats(190-210 g, 6-7 weeks old)were divided into two groups at random, GdCl3 group and control *** were collected at 0.5,1,6,12,and 24 hours from each group after *** alanine aminotransferase(ALT)and aspartate aminotransferase(AST)were measured by an automatic biochemical ***-αin serum was measured by enzyme-linked immunosorbent assay(ELISA). Malondialdehyde(MDA)in the liver mitochondria was measured by a colorimetric *** changes in the liver and immunohistochemical staining for caspase-3 were observed under an optical *** ratio of apoptotic cells was measured by TdT-mediated dUTP nick-end labeling(TUNEL),and ultrastructural features of apoptosis were observed with a transmission electron microscope(TEM). RESULTS:The levels of ALT in the GdCl3 group were lower than those in the control group after reperfusion for 0.5, 1,6 and 12 hours(P<0.05);and the levels of AST in the GdCl3 group were lower than those in the control group after reperfusion for 6 and 12 hours(P<0.05).The levels of TNF-αin the GdCl 3 group were lower than those in the control group after reperfusion for each time(P<0.05). The concentrations of MDA after reperfusion in the GdCl3 group were lower than those in the control group after reperfusion for 6,12 and 24 hours(P<0.05).After reperfusion for 0.5,1,6 and 12 hours,the integral optical density(IOD)of caspase-3-positive cells was lower in theGdCl3 group than in the control group(P<0.05).After reperfusion for 1,6,and 12 hours,the IOD of cells stained by TUNEL in the GdCl3 group was lower than that in the control group(P<0.05). CONCLUSIONS:GdCl3

关键词： gadolinium chloride Kupffer cell ischemia-reperfusion injury caspase-3 apoptosis

Study on products and reaction paths for synthesis of 3,4-dihydro-2H-3-phenyl-1,3-benzoxazine from phenol,aniline and formaldehyde

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Chinese Chemical Letters 2015年第3期26卷 348-352页

作者： Cheng-xi Zhang Yu-Yuan Deng Yi-Yang Zhang Po Yang Yi gu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan University

To study the synthesis of 3,4-dihydro-2H-3-phenyl-1,3-benzoxazine（benzoxazine）,the reaction paths of phenol,aniline and formaldehyde were investigated by analyzing the synthesis crude *** the aid of high-performance liquid chromatography（HPLC）,chromatographic column and preparative HPLC,seven compounds originated from the crude products were obtained and their chemical structures were *** reaction paths are proposed based on these *** show that Nhydroxymethyl aniline（HMA） derived from the reaction of formaldehyde and aniline is probably the key intermediate during the *** can react with itself or other reactants to form other intermediates,such as 1,3,5-triphenyl-1,3,5-triazinane and 2-（（phenylamino）methyl）phenol,and further form benzoxazine and byproducts.

关键词： aniline phenol formaldehyde itself crude originated react monomer probably claimed

Generation of human/rat xenograft animal model for the study of human donor stem cell behaviors in vivo

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World Journal of Gastroenterology 2007年第19期13卷 2707-2716页

作者： Yan Sun Dong xiao xing-Hua Pan Ruo-shuang Zhang guang-Hui Cui xi-gu Chen Center of Experimental Animals Sun Yat-sen University Guangzhou 510080 Guangdong Province China Institute of Comparative Medicine and Center of Experimental Animals Southern Medical University Guangzhou 510515 Guangdong Province China Clinic Experimental Department Kunming General Hospital Chengdu Military District of PLA Kunming 650032 Yunnan Province China

AIM： TO accurately and realistically elucidate human stem cell behaviors in vivo and the fundamental mechanisms controlling human stem cell fates in vivo, which is urgently required in regenerative medicine and treatments for some human diseases, a surrogate human-rat chimera model was developed. METHODS： Human-rat chimeras were achieved by in utero transplanting low-density mononuclear cells from human umbilical cord blood into the fetal rats at 9-11 d of gestation, and subsequently, a variety of methods, including flow cytometry, PCR as well as immunohistochemical assay, were used to test the human donor contribution in the recipients. RESULTS： Of 29 live-born recipients, 19 had the presence of human CD45^＋ cells in peripheral blood （PB） detected by flow cytometry, while PCR analysis on genomic DNA from 11 different adult tissues showed that 14 selected from flow cytometry-positive 19 animals possessed of donor-derived human cell engraftment in multiple tissues （i.e. liver, spleen, thymus, heart, kidney, blood, lung, muscle, gut and skin） examined at the time of tissue collection, as confirmed by detecting human 132- microglobulin expression using immunohistochemistry. Tn this xenogeneic system, the engrafted donor-derived human cells persisted in multiple tissues for at least 6 mo after birth. Moreover, transplanted human donor cells underwent site-specific differentiation into CK18-positive human cells in chimeric liver and CEHS-positive human cells in chimeric spleen and thymus of recipients. CONCLUSION： Taken together, these findings suggest that we successfully developed human-rat chimeras, in which xenogeneic human cells exist up to 6 mo later. This humanized small animal model, which offers an in vivo environment more closely resembling to the situations in human, provides an invaluable and effective approach for in vivo investigating human stem cell behaviors, and further in vivo examining fundamental mechanisms controlling human stem cell fates in the fut

关键词： Human umbilical cord blood-derived cells In utero xenogeneic transplantation Human-rat chimeras Embryonic microenvironment In vivo model

Design and Motion Control of Space Net Projectiles System 36

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Design and Motion Control of Space Net Projectiles System

Extraction of reflected waves from acoustic logging data using variation mode decomposition and curvelet transform

第36届中国控制会议

作者： xi Liang Yang Zhao Haiyu gu Cheng Wei Harbin Institute of Technology

ISBN: (纸本)9781538629185

Space net is an effective means of catching non-cooperative target without stability in high orbit,and it has a strong adaptability to the target *** this paper,a new net projectile mechanical structure is designed to improve mobility and safety at rail services,which can adjust the angle and the velocity of projectile *** unfolding mechanism dynamics model is built based on Lagrange’s *** motion control system is designed based on solution of the acceleration *** dynamic model of rope and net is established based on absolute nodal coordinate formulate（ANCF）,and the projection process is *** study can make important references on projectile strategy of space net.

关键词： Space net Capturing non-cooperative target Motion control Projectiles net system Dynamic simulation

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Petroleum Science 2024年第5期21卷 3142-3156页

作者： Fan-Tong Kong Yong-xiang Liu xi-Hao gu Li Zhen Cheng-Ming Luo Sheng-Qing Li Ocean College Jiangsu University of Science and TechnologyZhenjiang212100jiangsuChina School of Geosciences China University of Petroleum(East China)Qingdao266580Shandong.China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu610059SichuanChina

Remote reflection waves, essential for acquiring high-resolution images of geological structures beyond boreholes, often suffer contamination from strong direct mode waves propagating along the ***, the extraction of weak reflected waves becomes pivotal for optimizing migration image quality. This paper introduces a novel approach to extracting reflected waves by sequentially operating in the spatial frequency and curvelet domains. Using variation mode decomposition(VMD), single-channel spatial domain signals within the common offset gather are iteratively decomposed into high-wavenumber and low-wavenumber intrinsic mode functions(IMFs). The low-wavenumber IMF is then subtracted from the overall waveform to attenuate direct mode waves. Subsequently, the curvelet transform is employed to segregate upgoing and downgoing reflected waves within the filtered curvelet domain. As a result, direct mode waves are substantially suppressed, while the integrity of reflected waves is fully preserved. The efficacy of this approach is validated through processing synthetic and field data, underscoring its potential as a robust extraction technique.

关键词： Borehole acoustic reflection imaging Variation mode decomposition Curvelet transform Weak signal extraction

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反弹对撞式冲击放大器机理研究

工程力学 2023年第8期40卷 235-242页

作者：武双双金映丽闫明顾西平沈阳工业大学机械工程学院

为了在传统跌落冲击试验台上开展强冲击试验，以获得更高的加速度峰值。采用动态接触理论与经典碰撞理论相结合的方法，考虑能量损失，引入碰撞恢复系数，建立反弹对撞式冲击放大器的运动学模型，推导了加速度及其放大倍数计算公式，研... 详细信息

为了在传统跌落冲击试验台上开展强冲击试验，以获得更高的加速度峰值。采用动态接触理论与经典碰撞理论相结合的方法，考虑能量损失，引入碰撞恢复系数，建立反弹对撞式冲击放大器的运动学模型，推导了加速度及其放大倍数计算公式，研究了预留间隙、弹力绳刚度对冲击放大的影响规律。设计实验装置并进行试验，验证了理论模型的可行性和有效性。结果表明：理论计算与实验结果较吻合，最大误差约为7%；冲击放大台的最大加速度可达3780 g，加速度放大约13.5倍；存在一个理想预留间隙，使放大台加速度取得最大值，且选取较大跌落高度及理想预留间隙，更利于冲击放大；小刚度弹力绳对加速度具有一定的放大作用，但与预留间隙相比，影响较小。

关键词：强冲击放大台加速度冲击放大器理想预留间隙弹力绳刚度

Microstructural evolution of a Ni-Co based superalloy during hot compression atγ'sub-/super-solvus temperatures

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Journal of Materials Science & Technology 2021年第18期77卷 66-81页

作者： Peng Liu Rui Zhang Yong Yuan Chuanyong Cui Faguang Liang xi Liu Yuefeng gu Yizhou Zhou xiaofeng Sun Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China xi'an Thermal Power Research Institute Co.Ltd. Xi'an 710032China

The effects of strain rate on the microstructural evolution and deformation mechanism of a Ni-Co based superalloy were investigated by isothermal compression tests performed atγ'sub-solvus(1090℃)andγ'super-solvus temperatures(1150℃)with a wide strain rate range from 0.001 to 10 s^(-1)under a true strain of *** backscatter diffraction(EBSD),electron channeling contrast imaging(ECCI)and transmission electron microscope(TEM)techniques were used to characterize the *** results revealed that the dynamic recrystallization(DRX)volume fraction increased and stored energy of theγ'matrix grains decreased with increasing the strain rate duringγ'sub-solvus temperature deformation,while the opposite phenomena were observed duringγ'super-solvus temperature *** comprehensive effect of initial grain size,primaryγ'phase,twins and adiabatic temperature rise led to these *** primaryγ'particles undergone the deformation behavior within itself and obviously accelerated the DRX of the *** microstructural evolution proved that discontinuous dynamic recrystallization(DDRX)was the dominant mechanism during the hot deformation carried out at bothγ'sub-solvus andγ'super-solvus ***γ'particles obviously accelerated the nucleation step and retarded the growth step of DDRX duringγ'sub-solvus temperature ***,the acceleration effect of primaryγ'particles on DDRX increased with the increase of strain *** dynamic recrystallization(CDRX)was confirmed to be an assistant mechanism duringγ'super-solvus temperature deformation and was promoted with the increase of strain rate.

关键词： Ni-Co based superalloy Strain rate Primaryγ'precipitates Dynamic recrystallization Microstructural evolution

Optical Properties of Fullerenated Poly(epoxy propyl carbazole)

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Chinese Chemical Letters 1998年第9期9卷 835-837页

作者： Tao gu Wan xi CHEN Zhu De XU (Department of Chemistry, Zhejiang University, Hangzhou 310027) Zhejiang Univ Dept Chem Hangzhou 310027 Peoples R China

The optical properties of the fullerenated poly(epoxy propyl carbazole) (PEPC) have been investigated. Compared with pure PEPC, fullerenated PEPC has the same structure in the UV region of the absorption spectrum, and extends the active range to a longer wavelength. The apparent quenching of PEPC fluorescence was observed in the fullerenated polymer and it can be attributed to intramolecular excited state energy transfer.

关键词： fullerene (fullerenated) PEPC (poly(epoxy propyl carbazole)) optical properties

Phenotypic changes of human cells in human-rat liver during partial hepatectomy-induced regeneration

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World Journal of Gastroenterology 2009年第29期15卷 3611-3620页

作者： Yan Sun Dong xiao Hong-An Li Jin-Fang Jiang Qing Li Ruo-shuang Zhang xi-gu Chen Institute of Comparative Medicine andCenter of Experimental Animals Southern Medical UniversityGuangzhou 510515 Guangdong Province China Cancer Research Institute Southern Medical University Guangzhou 510515 GuangdongProvince China Department of Pathology ShiheziUniversity Shihezi 832002 Xinjiang Uygur AutonomousRegion China Institute of Gynecology and Obstetrics the ThirdAffiliated Hospital of Guangzhou Medical College Guangzhou510150 Guangdong Province China Center of ExperimentalAnimals Sun Yat-Sen University Guangzhou 510080 Guangdung Province China

AIM： To examine the human hepatic parenchymal and stromal components in rat liver and the phenotypic changes of human cells in liver of human-rat chimera （HRC） generated by in utero transplantation of human cells during partial hepatectomy （PHx）-induced liver regeneration. METHODS： Human hepatic parenchymal and stromal components and phenotypic changes of human cells during liver regeneration were examined by flow oytometry, in situ hybridization and immunohistochemistry. RESULTS： ISH analysis positive cells in hepatic demonstrated human Aluparenchyma and stroma of recipient liver. Functional human hepatocytes generated in this model potentially constituted human hepatic functional units with the presence of donor-derived human endothelial and biliary duct cells in host liver. Alpha fetoprotein （AFP）^＋, CD34^＋ and CD45^＋ cells were observed in the chimeric liver on day 10 after PHxinduced liver regeneration and then disappeared in PHx group, but not in non-PHx group, suggesting that dynamic phenotypic changes of human cells expressing AFP, CD34 and CD45 cells may occur during the chimeric liver regeneration. Additionally, immunostaining for human proliferating cell nuclear antigen （PCNA） showed that the number of PCNA-positive cells in the chimeric liver of PHx group was markedly increased, as compared to that of control group, indicating that donor-derived human cells are actively proliferated during PHx-induced regeneration of HRC liver. CONCLUSION： HRC liver provides a tool for investigating human liver regeneration in a humanized animal model.

关键词： Human-rat chimera Humanized liver Human hepatocyte-like cells Humanized hepaticfunctional unit Partial hepatectomy model Liver regeneration