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系统工程理论与实践 2018年第5期38卷 1118-1131页

作者：张婷邓新明黄瑜武汉大学经济与管理学院武汉430072 武汉大学战略管理研究所武汉430072 中国指数研究院北京100070

本文试图以探讨多点接触、市场进入和企业绩效三者间的关系作为切入点,达到为企业在动态的竞争环境下如何采取理性有效的竞争战略提出相关建议的目的.通过利用回归分析以及稳健性检验对所提出的假设进行了验证,其结果表明：多点接触与... 详细信息

本文试图以探讨多点接触、市场进入和企业绩效三者间的关系作为切入点,达到为企业在动态的竞争环境下如何采取理性有效的竞争战略提出相关建议的目的.通过利用回归分析以及稳健性检验对所提出的假设进行了验证,其结果表明：多点接触与市场进入行为间呈倒U型关系;市场进入行为对多点接触与企业绩效两者间的关系有着遮掩效应.具体表现为多点接触对企业绩效产生的正向直接效应大于其通过市场进入对企业绩效产生的负向间接效应;CEO政治背景对多点接触与市场进入行为间的关系有负向调节作用.因此基于以上分析结果,本文认为企业主动增加与竞争对手间存在的多点接触程度可以视为一种重要的非市场战略.

关键词：多点接触市场进入企业绩效 CEO政治背景非市场战略

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Nuclear Stopping and Nuclear Equation of State

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Nuclear Stopping and Nuclear Equation of State

Upregulation of PTEN involved in rosiglitazone-induced apoptosis in human hepatocellular carcinoma cells

第十三届全国核结构研讨会暨第九次全国“核结构与量子力学”专题讨论会

作者： Ying Yuan~(1 1)) Qingfeng Li~(2 2)) Zhuxia Li~(3.3.) Fu-Hu Liu~(1 4)) 1(Institute of Theoretical Physics,Shanxi University,Taiyuan,Shanxi 03.006,Peoples Republic of China) 2(School of Science,Huzhou Teachers College,Huzhou,Zhejiang 3.3.00,Peoples Republic of China) 3.China Institute of Atomic Energy,Post Office Box 275(18),Beijing 102413.Peoples Republic of China)

Nuclear stopping in heavy-ion collisions over a beam energy range from SIS and AGS up to SPS is studied in the framework of the modified Ultrarelativistic Quantum Molecular Dynamics transport model (UrQMD),in which mean field potentials of both formed and"preformed"hadrons(from string fragmentation) and medium-modified nucleon-nucleon elastic cross sections are *** is found that nuclear stopping is influenced by both the stiffness of the equation of state and medium modifications of nucleon-nucleon cross sections at SIS *** high SPS energies,a two-bump structure is shown in the experimental rapidity distribution of free protons,which can be understood by considering the preformed hadron *** details,please read.

关键词： Nuclear Stopping equation of state mean-field potential medium-modified cross section

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Acta Pharmacologica Sinica 2007年第6期28卷 879-887页

作者： Liang-qi CAO~2,Xi-lin CHEN~2,Qian WANG~3.Xiao-hui HUANG,Mao-chuan ZHEN,Long-juan ZHANG,Wen LI,Jiong BIDepartment of Hepatobiliary Surgery the First Affiliated Hospital of Sun Yat-Sen University,Guangzhou 510080,China Department of Hepatobiliary Surgery the First Affiliated Hospital of Sun Yat-Sen University Guangzhou China

Aim:To investigate the effects of rosiglitazone,a peroxisome proliferator-ac-tivated receptor gamma (PPART) agonist,on the expression of the phosphataseand tensin homologue deleted on chromosome 10 gene (PTEN) and cell growthin hepatocellular carcinoma cells,as well as the underlying mechanisms of ***:RT-PCR and Western blotting analyses were performed to de-tect transcription and the expression of PTEN in Hep3. cells treated withrosiglitazone.3.(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide as-say was used to evaluate cell *** cytometry,DNA fragmentation analysis,caspase enzymatic assay,and Hoechst 3.258 staining were used to determine ***,small interfering RNA was used to suppress ***:Rosiglitazone increased the expression of PTEN in a dose-and time-dependent manner through the PPARγ-dependent signal *** upregulation was concomitant with a decreased level of Aktphosphorylation,subsequently resulting in cell growth inhibition and apoptosisin Hep3. *** knockdown dramatically blocked these effects ***,the exposure of cells to rosiglitazone activated caspases-9and-3.during apoptotic ***:Thus,upregulation of PTENis involved in the inhibition of cell growth and the induction of cell apoptosis byrosiglitazone,suggesting that rosiglitazone may be useful in liver cancer therapyvia apoptosis.

关键词： rosiglitazone PTEN apoptosis hepato cellular carcinoma PPARγ

Intramuscular delivery of rAAV-mediated kallikrein gene reduces hypertension and prevents cardiovascular injuries in model rats

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Acta Pharmacologica Sinica 2007年第12期28卷 1898-1906页

作者： Yao WANG~(2,3.,Ling-bo HOU~(2,3.,Zhen-jun LIU~2,Yan WANG~2,Chun-lian CHEN~2,Xiao XIAO~(2,4),Dao-wen WANG~(2,5)~2 Institute of Hypertension and Department of Internal Medicine,Tongji Hospital,Tongji Medical College,Huazhong University of Science andTechnology,Wuhan 43.03.,China ~4 Departments of Molecular Genetics and Biochentistry and Gene Therapy Center University of Pittsburgh,Pittsburgh,PA 15261,USA Institute of Hypertension and Department of Internal Medicine Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China Departments of Molecular Genetics and Biochemistry and Gene Therapy Center University of Pittsburgh Pittsburgh USA

Aim:The overexpression of the human tissue kallikrein （HK） gene can reduceblood pressure and ameliorate the secondary syndromes associated with hyper-tension in animal *** current study was designed to investigate hy-potensive effect of intramuscular delivery of HK ***:We generatedan recombinant adeno-associated virus （rAAV） vector expressing human tissuekallikrein under the control of a cytomegalovirus promoter and administered therAAV-HK vector to a spontaneously hypertensive rat model at a dose of 1×1010virons/rat through intramuscular ***:A persistent,high-level ex-pression of HK post-gene delivery was confirmed by *** systolic bloodpressure in the rats receiving rAAV-LacZ and saline increased from 171.3.mmHg to182.3.mmHg 28 weeks' post *** contrast,the delivery of the HK gene byAAV vectors attenuated the increase of the systolic blood pressure in the *** systolic blood pressure was only slightly lowered （from a level of 174mmHg to 170.5 mmHg） post-vector *** difference in blood pres-sure between the treated group and the control groups is statistically significantat 12.6 *** hypotensive effect of rAAV-HK persisted until the end of thetesting *** addition,a significant amelioration of cardiovascularhypertrophy,renal injury,and collagen depositions in the rAAV-HK-treated ani-mals were also ***:All the effects are comparable with thoseof intravenous ***,the intramuscular administration of rAAV-HKmay be used in gene therapy for hypertension.

关键词： recombinant adeno-associated virus vector human tissue kallikrein intramuscular administration hypertension gene therapy cardiovascular remodeling spontaneously hypertensive rat

呼伦贝尔草原辉河湿地不同淹水状态的土壤碳氮磷特征比较

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生态学报 2018年第6期38卷 2204-2212页

作者：李兴福苏德荣吕世海布和沃强韩立亮罗琰北京林业大学草地资源与生态研究中心北京100083 中国环境科学研究院北京100012 内蒙古辉河国家级自然保护区管理局海拉尔021100

碳(C)、氮(N)、磷(P)生态化学计量比是生态系统过程及其功能的重要特征。为了比较不同淹水状态下草原区河岸湿地土壤生态化学计量特征差异,探讨用土壤生态化学计量特征来表征草原河岸湿地的退化状态,以呼伦贝尔草原辉河河岸湿地为研究对... 详细信息

碳(C)、氮(N)、磷(P)生态化学计量比是生态系统过程及其功能的重要特征。为了比较不同淹水状态下草原区河岸湿地土壤生态化学计量特征差异,探讨用土壤生态化学计量特征来表征草原河岸湿地的退化状态,以呼伦贝尔草原辉河河岸湿地为研究对象,分别选择完全退化和未退化河岸湿地,从中选取常年淹水区域(W)、年际干湿交替区域(WD)以及河岸带边缘多年未曾淹没的干燥区域(D)为观测样地,对比研究退化与未退化草原河岸湿地土壤C、N、P化学计量比在不同淹水状态下的表征。结果表明:(1)随着淹水状态的改变,不论是退化河岸湿地还是未退化河岸湿地,不同淹水状态下的土壤C/N、C/P、N/P均差异显著(P3.08和28.25,与未退化河岸湿地相比(7.85、95.48、11.41)值显著升高;(3.相关性分析结果显示,土壤总磷与有机碳、全氮显著正相关,与C/N、C/P、N/P负相关,这可能是限制退化河岸湿地土壤养分元素循环的主要因素。研究结果表明:呼伦贝尔草原辉河河岸湿地不同淹水状态的土壤碳、氮、磷特征差异明显(P<0.05),尤其是土壤C/P和N/P。与未退化河岸湿地相比,退化河岸湿地的C/N、C/P、N/P均明显高于未退化河岸湿地(P<0.05),因此可以将土壤碳、氮、磷化学计量比特征作为草原区河岸湿地退化的评价指标。

关键词：草原区河岸湿地土壤碳氮磷比不同淹水状态辉河湿地

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Effects of hypoxia,hyperoxia on the regulation of expression and activity of matrix metalloproteinase-2 in hepatic stellate cells

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World Journal of Gastroenterology 2001年第5期7卷 647-651页

作者： Ping-Sheng Chen~(1,2) Wei-Rong Zhai~1 Xiao-Mei Zhou~3.Jin-Sheng Zhang~1 Yue-E Zhang~1 Yu-Qin Ling~1 Ying-Hong Gu~1 1 Department of Pathology,School of Basic Medical Sciences,Fudan University,Shanghai 20003.,China2 Ping-Sheng Chen now works in the Department of Pathology,School of Basic Medical Sciences the (former Nanjing Railway Medical College),Southeast University,Nanjing 210009,China3.Institute of Cancer Research,Shanghai 20003.,China Department of Pathology School of Basic Medical Sciences Fudan University 138 Yixueyuan Road Shanghai 200032 China.

AIM: To study the effects of hypoxia, hyperoxia on the regulation of expression and activity of matrix metalloproteinase-2 (MMP-2) in hepatic stellate cells (HSC). METHODS: The expressions of MMP-2, tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) and membrane type matrix metalloproteinase-1 (MT1-MMP) in cultured rat HSC were detected by immunocytochemistry (ICC) and in situ hybridization (ISH). The contents of MMP-2 and TIMP-2 in culture supernatant were detected with ELISA and the activity of MMP-2 in supernatant was revealed by zymography. RESULTS: In the situation of hypoxia for 12h, the expression of MMP-2 protein was enhanced (hypoxia group positive indexes: 5.7 +/- 2.0, n=10; control: 3.2 +/- 1.0, n = 7; P3.6 +/- 1.0, n = 7; P 3.4 +/- 1.922, n = 9; control: 17.277 +/- 7.424, n = 11; P 3.4 +/- 1.083. n = 12; P < 0.05), and the expression of MT1-MMP was increased. CONCLUSION: HSC is sensitive to the oxygen, hypoxia enhances the expression of MMP-2 and the effect is more marked at the early stage; hyperoxia mainly raises the activity of MMP-2.

关键词： Animals Cell Division Cell Hypoxia Cells, Cultured Gelatinase A Gene Expression Regulation, Enzymologic Hepatocytes Hyperoxia Metalloendopeptidases RNA, Messenger Rats Rats, Sprague-Dawley Research Support, Non-U.S. Gov't Tissue Inhibitor of Metalloproteinase-2

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黑铁国家与白雪人民

今日民航 2010年第10期 72-73页

作者： 3.O

《44号孩子》[英]汤姆·罗伯·史密斯在这个彼此怀疑、人人自危,随时面临生存危险的残酷世界里,主人公里奥经历了命运的大翻转,迷失的自我慢慢觉醒。因为44号孩子,他看到了他一直忠诚效命的国家的真相:因为44号孩子,他得以窥破他与妻子... 详细信息

《44号孩子》[英]汤姆·罗伯·史密斯在这个彼此怀疑、人人自危,随时面临生存危险的残酷世界里,主人公里奥经历了命运的大翻转,迷失的自我慢慢觉醒。因为44号孩子,他看到了他一直忠诚效命的国家的真相:因为44号孩子,他得以窥破他与妻子关系的真相;因为44号孩子,他看到了自己一直不愿正视的与家人关系的真相。其实救赎,也是自救。

关键词：悬疑小说国家机器吉田修一主人公史密斯心理师