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MASS SPECTROMETRLC STUDY OF THE CHEMLCALKINETICS OF THE CH2CIO OXY RADLCAL REACTIONS

质谱学报 1999年第Z1期 25-26页

作者： Fuxiang WU, Robert.CARR (department of Chemical Engineering and Materials Scienceuniversity of minnesota 421 Washington Avenue S.E,{3. mn 55455, usa)

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Comparison of Renal Hemodynamic Effect of Ramiprilat to Captopril: Possible Role of Kinins

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中华高血压杂志(中英文) 1994年第2期 108-113页

作者： Ke Chen Zimmerman BG(department of Pharmacology, university of minnesota Medical School, minneapolis,{3. )

The purpose of this study was to compare the angiotensin converting enzyme (ACE ) inhibitor ramiprilat to captopril with respect to its efficacy in decreasing blood pressure (BP) and increasing renal blood flow (RBF),when administered intravenously (i. v. ),or as in a separate group of experiments when given intrarenally (i. a ). Thirty-four anesthetized rabbits were employed in 3.groups of experiments in which BP and RBF were the measured parameters. In Group I,ramiprilat (1 mg/kg and 0. 5 mg/kg· h-1 i. v. )decreased BP from 107 ± 5 to 83. 8 mmHg and increased RBF from 3.± 3.ml/min to 44± 7 ml/min. Captopril (2 mg/kg and 1 mg/kg· h-1 i. v. ) decreased BP from 99 ± 6 to 77 ± 8 mmHg and increased RBF from 3.±1 to 42± 3.ml/min. Both ramiprilat and captopril abolished the pressor effect and greatly attenuated the renal vasoconstrictor response to injected angiotensin I. When the ACE inhibitors were administered in graded doses i. a. (Group Ⅱ ), they caused a similar increase in RBF , but a lesser decrease in BP compared to those when given i. v. Ramiprilat was more potent than captopril by either route of administration. In the presence of HK2 kinin receptor blockade by HOE 140 (Group Ⅲ ), the effect of ramiprilat and captopril on BP and RBF did not differ from that in Group Ⅱ. In conclusion, ramiprilat and captopril cause a similar renal hemodynamic effect and decrease in BP,and there is no difference in their efficacy either in the presence or absence of BK antagonism.

关键词： angiotensin converting enzyme captopril renal blood flow

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Abrupt climate change of EastAsian Monsoon at 13. kaBP inferred from a high resolu-tion stalagmite δ18O record

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Science Bulletin 2005年第23期50卷 2765-2769页

作者： JIANG Xiuyang1, WANG Yongjin1, KONG Xinggong1,WU Jiangying1, SHAO Xiaohua1, XIA Zhifeng1 & CHENG Hai2 1. College of Geography Science, Nanjing Normal university, Nanjing210097, China 2. department of geology and {3., university of minnesotaminneapolis, mn 55455, usa College of Geography Science Nanjing Normal University Nanjing 210097 China department of geology and geophysics University of Minnesota Minneapolis MN 55455 USA

23.Th ages and oxygen isotope data of a stalagmite from Shanbao Cave in Hubei Province characterize thEast Asian Monsoon precipitation from 13. to127 ka. Thdecadal-scale high-resolution δ18O record reveals a detailedtransitional process from the Penultimate Glaciation to thLast Interglaciation. As established with 23.Th dates, the agof the Termination II is determined to be 129.5±1.0 kaBPwhich supports the Northern Hemisphere insolation as thtriggers for the ice-age cycles. In our δ18O record, the glacialinterglacial fluctuation reaches about 4‰, almost the samlevel as in other Asian Monsoon cave stalagmite δ18O recordThe transition of the glacial/interglacial period in our recordcan be recognized as four stepwise stages, among which, arapid rise of monsoon precipitation follows the stage o“Termination II pause”. The rapid rise is synchronous withthe abrupt change of global methane concentration, whichreflects that an increase in both Asian Monsoon precipitationand tropical wetland plays an important role in the globaclimate changes.

关键词： stalagmite high-resolution U/Th age Termination II.

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Stem cell pluripotency and transcription factor Oct4

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Cell Research 2002年第Z2期 321-329页

作者： GUANG JIN PAN, ZENG YI CHANG, HANS R. SCHOLER, DUANQING PEI departments of Pharmacology and Biological Sciences & Biotechnology, Schools of Sciences and Medicine,Tsinghua university, Beijing 100084, China Center for Animal Transgenesis and Germ Cell Research, School of Veterinary Medicine, department of Animal Biology, university of Pennsylvania, New Bolton Center, 3.2 West Street Road, Kennett Square, PA 193.8, usa,department of Pharmacology, university of minnesota, minneapolis, mn 55455, usa

Mammalian cell totipotency is a subject that has fascinated scientists for generations. A long lasting question whether some of the somatic cells retains totipotency was answered by the cloning of Dolly at the end of the 20th century. The dawn of the 21st has brought forward great expectations in harnessing the power of totipotentcy in medicine. Through stem cell biology, it is possible to generate any parts of the human body by stem cell engineering. Considerable resources will be devoted to harness the untapped potentials of stem cells in the foreseeable future which may transform medicine as we know today. At the molecular level, totipotency has been linked to a singular transcription factor and its expression appears to define whether a cell should be totipotent. Named Oct4, it can activate or repress the expression of various genes. Curiously, very little is known about Oct4 beyond its ability to regulate gene expression. The mechanism by which Oct4 specifies totipotency remains entirely unresolved.

关键词： Oct4 ES cells pluripotency totipotency stem cells cloning.

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盾构推进对相邻桩体力学影响的实用计算方法

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同济大学学报（自然科学版） 1997年第3期25卷 274-280页

作者：李永盛黄海鹰同济大学地下建筑与工程系上海200092 美国明尼苏达大学土木与环境工程系明尼阿波利斯mn55455

利用弹性力学开尔文（Kelvin）解及弹性地基梁理论导出盾构推进对相邻桩体内力及挠曲影响的计算公式，结合上海地铁一号线的实测结果进行了工程实例分析．所提出的计算方法及其计算程序为预估桩体因盾构推进产生的挠曲与弯矩、确定盾构... 详细信息

利用弹性力学开尔文（Kelvin）解及弹性地基梁理论导出盾构推进对相邻桩体内力及挠曲影响的计算公式，结合上海地铁一号线的实测结果进行了工程实例分析．所提出的计算方法及其计算程序为预估桩体因盾构推进产生的挠曲与弯矩、确定盾构与桩体的最小允许间距等提供了定量化分析依据．

关键词：盾构桩基挠曲弯矩地基计算

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Stable isotope records of plant cover change and monsoon variation in the past 2200 years:evidence from laminated stalagmites in Beijing,China

Stable isotope records of plant cover change and monsoon var...

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中国科学院地质与地球物理研究所2003.术年会

作者： JU ZHI HOU,MING TAN.HAI CHENG AND TUNG SHENG LIU Institute of geology and geophysics,Chinese Academy of Sciences,Beijing 100029. China Institute of Earth Environment.Chinese Academy of Sciences.Xi’an.Shaanxi Province 710054.department of geology and geophysics,university of minnesota,minneapolis mn 55455,usa

Two stalagmites collected from the Shihua cave in the southwestern suburb of Beijing were dated by annual layer *** results are consistent with thermal ionization mass spectrometry Th *** carbon isotope variation of stalagmites is dominated by plant cover change,which largely reflects climate change and monsoon *** isotopes are mainly affected by *** is related to summer and winter monsoon *** combination of carbon and oxygen isotopes can therefore be a proxy of plant cover change and monsoon *** stable isotope results show that lower carbon isotope values of the stalagmites between 200 BC and AD 1000 probably imply dense plant cover and an episode dominated by humid summer ***～1000 to AD *** dominant monsoon alternated between the winter monsoon and the summer ***～AD 1450.a significant jump in carbon isotope ratios and increasing oxygen isotope ratios has been *** less plant cover and the probable dominance of dry winter *** results are consistent with historical documents of the region.

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EPR studies of mn^(2+) in the Loess Plateau of central China: Implication for variation of the East Asia summer monsoon

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Chinese Science Bulletin 1998年第1期43卷 72-75页

作者： CHEN Jun\+1, JI Junfeng\+1, SU Yuanxia\+2 and LU Huayu\+3.. department of Earth Sciences, Nanjing university, Nanjing 210093. China 2. Center of Material Analysis, Nanjing university, Nanjing 210093. China 3. Xi’an Laboratory of Loess and Qu department of Earth Sciences Nanjing University Nanjing China Center of Material Analysis Nanjing University Nanjing China Xi’an Laboratory of Loess and Quaternary geology Chinese Academy of Sciences Xi’an China

mn 2+ EPR intensity recorded in the Chinese loess_paleosol sequence shows close correlation with magnetic susceptibility and Sr content as well as the oscillation of paleoclimate. Thus mn 2+ EPR signal can serve as an... 详细信息

关键词： paleomonsoon loess paleosol EPR signal of mn 2+

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一氧化氮参与大鼠脊髓中伤害性信号的传递和对此传递的下行抑制 :免疫细胞化学研究(英文)

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山西医科大学学报 2000年第S1期31卷 93-96页

作者：高旺才美国明尼苏达大学神经科学研究

一氧化氮 (NO)近来被认为是神经系统执行各种信息传递任务的气体性递质或调质 ,现已知NO易化脊髓水平痛觉的传递。我们推测 ,在此处 ,NO可能也参与痛觉的脑干下行性抑制系统。本实验用脚掌注射福尔马林引起同侧脊髓腰膨大背角神经元伤害... 详细信息

一氧化氮 (NO)近来被认为是神经系统执行各种信息传递任务的气体性递质或调质 ,现已知NO易化脊髓水平痛觉的传递。我们推测 ,在此处 ,NO可能也参与痛觉的脑干下行性抑制系统。本实验用脚掌注射福尔马林引起同侧脊髓腰膨大背角神经元伤害性c fos表达 ,结合鞘内注射一氧化氮合成酶抑制剂的方法 ,来观察NO是否参与脊髓背角神经元痛反应以及对于该反应的下行抑制活动。第一部分实验表明 ,一侧脚掌注射福尔马林可引起同侧脊髓腰膨大背角神经元伤害性c fos表达 ;鞘内注射一氧化氮合成酶抑制剂左旋硝基精氨酸L NNA可剂量依赖性地抑制其表达。在第二部分实验中 ,先对大鼠实施了脊髓胸段背半部单侧离断手术 ,然后双侧脚掌注射福尔马林 ,此时可见完好侧脊髓背角c fos表达数量明显少于损伤侧。这种差异只能解释为完好侧保存着由脑干发出、下行投射到脊髓腰膨大的痛觉抑制系统抑制了该侧背角c fos表达的结果 ;进一步实验证明 ,这种抑制作用可以被鞘内注射L NNA取消。这个结果表明 :NO不仅易化脊髓水平伤害性信号的传递活动 ,同时也增强痛觉的下行性抑制系统的作用。

关键词：一氧化氮精氨酸脱敏作用脊髓疼痛基因,Fos 大鼠

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Geochemistry of Sedimentation and Diagenesis in Qixia Formation (Early Permian) of Badong, Hubei Province, China: Implications for T-R Cycle Interpretation

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Journal of Earth Science 1999年第2期18卷 56-62页

作者： Yan Jiaxin Zhao Laishi Faculty of Earth Sciences, China university of Geosciences, Wuhan 43.074 Fang Nianqiao department of geology and Mineral Resources, China university of Geosciences, Beijing 100083

Combined with sedimentary observation and mineralogical research on a type of drusy celestite of early diagenesis in origin, this geochemical study on the Qixia Formation at the Shuibuya Section, Badong County, Hubei Province of south China evaluates the contribution of sedimentation and diagenesis to the mass fractions of CaO, Al 2O 3. MgO, SiO 2, Fe 2O 3. Na 2O, K 2O, mn, Sr, P and Ba in the carbonates. The Sr, initially released from the stabilization of carbonate calcium mineral, precipitated with sulfate ion as celestite in early diagenetic environment, where sulfate reduction was the minimum. Then it redistributed in burial diagenetic environment, where celestite was replaced by calcite. The fractions of the MgO and SiO 2 in the carbonates were mainly modified by the early dolomitization and silicification respectively. That of the Na 2O was overprinted by the burial diagenesis. Multivariate statistical analysis on data of sixty bulk rocks indicates that the mass fractions of the Al 2O 3. K 2O, Fe 2O 3. mn, CaO, P and Ba were affiliated with the sedimentary factor despite the obvious decrease of CaO during early dolomitization and silicification. Among them, the Al 2O 3.and K 2O mainly represent the detrital components. In addition, a dysaerobic sedimentary background was confirmed by trace element measurement and information derived from the formation of the celestite. This genetic discrimination facilitates the interpretation of the transgressive regressive (T R) cycle and specialities featured this unusual carbonate unit.

关键词： sedimentation diagenesis celestite geochemistry T R cycle.

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TRACE AND MINOR ELEMENT GEOCHEMISTRY OF XIANGDONG TUNGSTEN DEPOSITS

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Journal of Central South university 1996年第1期8卷 75-77页

作者： Chen Zilong Yang Chuxiong(department of geology, Central South university ofTechnology, Changsha 410083. China)

Geochemical characteristics of trace and minor elements in some strata of geosynclinal tectonic layer, platform tectonic layer, in granite of Diwa stage, altered rocks and wolframite in the Xiangdong Tungsten Mine are systematically studied. Enrichment of W, Sn and Cu in geosynclinal tectonic layer could be one part of mineralization. Different types of alteration might result in variance of distribution of the same trace or minor element. mNb/mTa and mmn/mFe ratios, contents of Nb and Ta in wolframite vary with vein groups′ location.

关键词： trace element minor element granite tungsten deposits Hunan

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