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Phytoestrogen genistein decreases contractile response of aortic artery in vitro and arterial blood pressure in vivo

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Acta Pharmacologica Sinica 2004年第3期25卷 59-64页

作者： Hong-fang LI1,Long-de WANG2,Song-yi QU department of Physiology,lanzhou Medical College,lanzhou {3. 2Affiliated Hospital,Gansu Chinese Medical College,lanzhou 73.020,china department of Physiology Lanzhou Medical College Affiliated Hospital Gansu Chinese Medical College

AIM: To determine the mechanisms of effects of phytoestrogen genistein on the contracted rabbit aortic arteries in vitro, and observe the effect of genistein and 17-β estradiol on mean arterial pressure (MAP) in ovariectomized (OVX) rats. METHODS: (1) Strips of rabbit aortic smooth muscle were suspended in organ baths containing Kreb’s solution, and then isometric tension was measured. (2) Female mature Wistar rats underwent a bilateral ovariectomy (OVX). Sham-operated rats (SHAM) were used as controls. After administration of genistein (0.4 mg·kg-1·d-1, sc), 17-β estradiol (1 mg·kg-1·d-1, sc) or theirvehicle sesame oil for 21 d,MAP was measured. RESULTS: (1) Similar to 17-β estradiol, genistein could dose-dependently relax 40 mmol/L KCl-precontracted arterial strips. Incubation with Nω-L-nitro-arginine (L-NNA), methylene blue (MB), indomethacin, propranolol or endothelium removal did not affect relaxation induced by genistein. In calcium-free solution containing 0.01mmol/L egtazic acid (EGTA), genistein inhibited not only the first phase contraction induced by noradrenaline (NA), but also the second contraction induced by CaCl2. In addition, genistein could reduce the contractile responses of NA, KCl and CaCl2, and shift their cumulative concentration-response curves rightward. (2) MAP in OVX rats was significantlyhigher compared with that of SHAM rats. However,after chronically treatment with genistein or 17-β estradiol for 21 d the baseline MAP in OVX rats was reduced significantly. CONCLUSIONS: (1) The vasodilator effect of genistein in vitro is endothelium independent and not related to the nitric oxide, its mechanisms being probably due to inhibition of Ca2+ influx through calcium channels in a noncompetitive manner and Ca2+ release from intracellular store induced by NA. (2) Administration of genistein or 17-β estradiol can chronically decrease MAP in OVX rats.

关键词： genistein aorta smooth muscle muscle relaxation calciumchannel vascular endothelium blood pressure

The relativistic consistent angular-momentum projected shell model study of the N=Z nucleus ^(52)Fe

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1471-1476页

作者： LI YanSong1,2 & LONG GuiLu1,2 1 department of Physics,Tsinghua university,Beijing 100084,china 2 Center of Nuclear Theory,National Laboratory of Heavy Ion Accelerator of {3.,{3. 73.000,china 1. department of Physics Tsinghua University Beijing 100084 China 2. Center of Nuclear Theory National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

The relativistic consistent angular-momentum projected shell model(ReCAPS) is used in the study of the structure and electromagnetic transitions of the low-lying states in the N=Z nucleus *** model calculations show a reasonably good agreement with the *** backbending at 12+ is reproduced and the energy level structure suggests that neutron-proton interactions play important roles.

关键词： ReCAPS relativistic mean field angular-momentum projection method 52Fe neutron-proton interaction

Gas formation mechanism of marine carbonate source rocks in china

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Science china Earth Sciences 2005年第4期48卷 441-453页

作者： ZHAO Wenzhi1, WANG Zhaoyun1, HE Haiqing2, ZHANG Mingjie3. WANG Hongjun1, WANG Yunpeng4 & QIN Yong5 1. Research Institute of Petroleum Exploration & Development, Petrochina, Beijing 100083. china 2. Petrochina Exploration & Production, Beijing 100011, china 3. department of geology, lanzhou university, lanzhou 73.000, china 4. Guangzhou Geochemical Institute, Chinese Academy of Sciences, Guangzhou 510640, china 5. china university of Mining and Technology, Xuzhou 221000, china 1. Research Institute of Petroleum Exploration & Development 100083 PetroChinaBeijin China 2. Petrochina Exploration & Production 100011 Beijing China 3. department of geology Lanzhou University 730000 Lanzhou China 4. Guangzhou Geochemical Institute Chinese Academy of Sciences 510640 Guangzhou China 5. china university of Mining and Technology 221000 Xuzhou China

By breaking through the conventional ideology on the study of gas-formation mechanism of source rocks which focused on merely the characteristics of source rocks them- selves, and based on the development and distribution characteristics of marine carbonate source rocks in the medium-to-bottom parts of the Chinese superimposed sedimentary basins as well as various processes in the course of gas generation and reservoir forming, the complex hydrocarbon-generating model of carbonates is established. Such a model concerns not only the “three-stage” gas formation characteristics of carbonates, but also the gas generation process due to a thermal cracking of oil and the re-generation process of gas from heated secondary organic matters during the gas-generation and reservoir-forming course. The high-quality hy- drocarbon generating matter of marine carbonate source rocks determined a high gas-oil ratio and tended to form paleo-oil-reservoirs, representing an enrichment process of organic matters. The thermal cracking of oil in palaeo-oil-reservoirs is an important means for the effective forma- tion of gas reservoirs. The secondary organic matters in carbonate reservoirs may regenerate gas after a secondary deep burial, thus becoming an effective gas source.

关键词： carbonate, three-stage hydrocarbon generation, inhibitive effect of maturity, oil-cracking gas, second-ary asphalt gas.

SYNTHESIS, CHARACTERIZATION OF 2-[2-(3.NITRO-4-METHOXYLPHENYL) VINYLI-1-METHYLPYRIDINIUM PENTA AND HEXANITRATO RARE EARTH(Ⅲ) COMPLEXES

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Chinese Chemical Letters 1996年第1期7卷 89-90页

作者： Huan Wang JING Zi Jie HOU Shu Ying CHEN Du LI(department of Chemistry lanzhou university, lanzhou 73.000) department of Chemistry Lanzhou University Lanzhou 730000

The bile complexes have been Synthesised by the reaction of rare earth nitrate with 2-[2-3.nitro- 4-methoxylphenyl) vinyl ]-1-methylpyridinium nitrate in ethanol solution and have been characterized by IR. UV and 1H NMR spectre TG-DTA, molar conductance and X-ray powder diffraction . The results show that the Crystal form of Nd complex containing one molecular water as a ligand is eleven coordinated and is different from the others.

关键词： VINYLI-1-ME CHARACTERIZATION OF 2 NITRO-4-METHOXYLPHENYL

ANALYTICAL FORMULAS OF SOLUTIONS OF GEOMETRICALLY NONLINEAR EQUATIONS OF AXISYMMETRIC PLATES AND SHALLOW SHELLS

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Acta Mechanica Sinica 1990年第1期6卷 69-80页

作者： Zheng Xiaojing Zhou Youhe, department of Mechanics, lanzhou university 1. department of Mechanics Lanzhou University Lanzhou China

Starting from the step-by-step iterative method, the analytical formulas of solutions of the geometrically nonlinear equations of the axisymmetric plates and shallow shells, have been obtained. The uniform convergence of the iterative method, is used to prove the convergence of the analytical formulas of the exact solutions of the equa- tions.

关键词： circular thin plates and shallow shells axisymmetric deformation nonlinear equations exact solution analytical formulas

Hydrogen isotopic characteristics and their genetic relationships for individual n-alkanes in plants and sediments from Zoigê marsh sedimentary environment

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Science china Earth Sciences 2010年第9期53卷 1329-1334页

作者： DUAN Yi1, ZHENG ChaoYang2 & WU BaoXiang1 1 Key Laboratory of Petroleum Resources Research, Institute of geology and Geophysics, Chinese Academy of Sciences, lanzhou 73.000, china 2 {3. of geology, Northwest university, Xi’an 710069, china 1. Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China2. Department of Geology Northwest University Xi’an 710069 China

To understand internal relations of their hydrogen isotopic compositions in typical marsh environment, we, using GC-IRMS analytical technique, measured the hydrogen isotopes of individual n-alkanes in the herbaceous plant, woody plant leaf, and sediments from Zoigê marsh in china. The results show significant differences in the hydrogen isotopic compositions of n-alkanes among the different kinds of plants and the different species in the same kind. δD values of n-alkanes in the herbaceous plants (from -254‰ to -184‰) are lighter than those in woody plant leaf ( from -195‰ to -142‰ ), and the hydrogen isotopic compositions of n-alkanes in K. tibetica P. are lighter than P. pratensis L. The mean δD values of n-alkanes in the sediments from Zoigê marsh reflect that they were derived from herbaceous plants, which is consistent with the peat samples being composed mainly of herbaceous plant remnants. The significant differences in hydrogen isotopic compositions of n-alkanes among the sedimentary samples are caused possibly by environment factors and the difference in input quantity of different herbaceous plants. A certain negative correlation exists between the δ13. and δD values of n-alkanes in the samples, and plant types can be distinguished using the cross plot of δD vs. δ13. values of n-alkanes in the plants. These data and recognitions provide scientific basis for hydrogen isotopic applied research of individual n-alkanes.

关键词： marsh environment plants sediments individual lipids hydrogen isotopes genetic relationship

Texual Cohesion and Coherence

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兰州大学学报（社会科学版） 2000年第S1期28卷 250-256页

作者： Zhang Haiying (Foreign Languages Teaching department, Northwest Normal university lanzhou,{3., china)

Cohesion and coherence are two of the most important components in discourse analysis. This thesis investigales some cohesive devices and coherent means. At zhe same time, it gives an account of how a text is identifi... 详细信息

关键词： text cohesion coherence

A Few Words on Lennie

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兰州大学学报（社会科学版） 2000年第S1期28卷 12-14页

作者： Zhang Li (Foreign Languages of department, Northwestern Nationalities university, lanzhou, 73.070,{3.)

Some aspects of Lennies character are discussed in this paper. Lennie appears in the novel Of Mice and Men by John Steinbeck.

关键词： Steinbeck Of Mice and Men Lennie’s character

A Study on the Driving Force for Binding of Benzene Derivatives by α-and β-Cyclodextrin

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Chinese Chemical Letters 1998年第5期9卷 463-464页

作者： Shuang Hui LUO Hui Ming JMNG You Cheng LIU(National Laboratory of Applied organic Chemistry, lanzhou university, lanzhou 73.000)Qing Xiang GUO (department of Chemistry, {3. of Science and Technology of china, Hefei 23.026) lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China Univ Sci & Technol china Dept Chem Hefei 230026 Peoples R China

A three-dimensional diagram shows that the association constants (Ka) for the inclusionof a- and 6-CD with substitUted benzene are mainly correIated with the molar refraction (R.) andhydrophobic constant (%) of the substitUents of guest compounds. It reveals that the inclusion ofcyclodextrin with the substitUted benzene is dondnantly driYen by van der Waals forces andhydrophobic interactions.

关键词： benzene derivatives cyclodextrin driving force inclusion complexation