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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 730000 2Affiliated Hospital,gansu Chinese Medical College,lanzhou 730020,china Department of Physiology Lanzhou Medical College Lanzhou 730000 Affiliated Hospital Gansu Chinese Medical College Lanzhou 730020

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

Textual research of Wudu earthquake in 186 B.C. in gansu province, china and discussion on its causative structure

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Acta Seismologica Sinica(English Edition) 2007年第6期20卷 696-707页

作者：袁道阳雷中生何文贵熊振葛伟鹏刘兴旺刘百篪 lanzhou Institute of Seismology China Earthquake Administration earthquake administration of Jiangsu province

On the basis of the textual research on the historical earthquake data and the field investigation of Wudu earthquake occurred in 186 B.C., we suggest that the earthquake parameters drawn from the present earthquake catalogs are not definite and amendments should be made. The heavily-damaged area of this earthquake should be located between Jugan township of Wudu County and Pingding township of Zhouqu County. Its epicenter should be in the vicinity of Lianghekou in Wudu County with a magnitude of about 7-7 1/4 and an intensity of about IX-X. The major axis direction of the heavily-damaged area should be in the WNW direction that is approximately consistent with the strike of the middle-east segment of Diebu-Bailongjiang active fault zone, and the origin time should match up to that of the latest paleoearthquake event [before （83±46） B.C.] obtained by the trench investigation. Certain seismic rupture evidences are still preserved on this fault segment. Therefore, we propose on the basis of comprehensive analysis that the causative structure of the M 7-7 1/4 Wudu earthquake in 186 B.C. should be in the middle-east segment of Diebu-Bailongjiang active fault zone.

关键词： Wudu earthquake in 186 B.C. textual research of historical earthquake causative structure Diebn-Bailongjiang fault zone

Upper crust structure of eastern A’nyemaqên suture zone: Results of Barkam-Luqu-Gulang deep seismic sounding profile

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Acta Seismologica Sinica(English Edition) 2007年第6期20卷 628-640页

作者：张先康Geophysical Exploration Center china earthquake administration 杨卓欣Geophysical Exploration Center china earthquake administration 徐朝繁Geophysical Exploration Center china earthquake administration 潘纪顺Geophysical Exploration Center china earthquake administration 刘志Geophysical Exploration Center china earthquake administration 王夫运Geophysical Exploration Center china earthquake administration 嘉世旭Geophysical Exploration Center china earthquake administration 赵金仁Geophysical Exploration Center china earthquake administration 张成科Geophysical Exploration Center china earthquake administration 孙国伟 Geophysical Exploration Center China Earthquake Administration

Barkam-Luqu-Gulang deep seismic sounding profile runs from north of Sichuan province to south of gansu province. It is located at the northeastern edge of Tibetan Plateau and crosses eastern A＇nyemaqên suture zone. The upper crust structures around eastern A＇nyemaqên suture zone and its adjacent area are reconstructed based on the arrival times of refracted Pg and Sg waves by using finite difference method, ray tracing inversion, time-term method and travel-time curve analysis. The results show that the depth variation of basement along profile is very strong as indicated by Pg and Sg waves. The basement rose in Zoigê basin and depressed in eastern A＇nyemaqên suture zone, and it gradually rose again northward and then depressed. The results also indicate that eastern A＇nyemaqên suture zone behaves as inhomogeneous low velocity structures in the upper crust and is inclined to- ward the south. Hoh Sai Hu-Maqên fault, Wudu-Diebu fault and Zhouqu-Liangdang fault are characterized by low velocity distributions with various scales. The distinct variation in basement depth occurred near Hoh Sai Hu-Maqên fault and Zhouqu-Liangdang fault, which are main tectonic boundaries of A＇nyemaqên suture zone. Wudu-Diebu fault, located at the depth variation zone of the basement, possibly has the same deep tectonic background with Zhouqu-Liangdang fault. The strongly depressed basement characterized by low velocity distribution and lateral inhomogeneity in A＇nyemaqên suture zone implies crushed zone features under pinching action.

关键词： eastern A'nyemaqên suture zone deep seismic refraction upper crust structures

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以科学发展观推进金昌市防震减灾事业发展

西北地震学报 2005年第4期27卷 394-396页

作者： earthquake administration of Jinchang City(earthquake administration of Jinchang City,Jinchang gansu 737100,china) 金昌市地震局甘肃金昌737100

前言金昌市位于河西走廊中东部,近年来一直被中国地震局列为全国地震重点监视防御区和重点危险区,同时又是甘肃省政府确定的防震减灾十年目标首批达标城市之一,防震减灾工作任务艰巨.

关键词：金昌防震减灾发展

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张掖市震灾预防和灾后重建工作

西北地震学报 2005年第4期27卷 392-393页

作者： earthquake administration of Zhangye City(earthquake administration of Zhangye City,Zhangye gansu 734000,china) 张掖市地震局甘肃张掖734000

前言省委、省政府的正确领导下,在省地震局具体指导和大力支持下,张掖市政府和地震局认真贯彻"预防为主,防御与救助相结合"的防震减灾工作方针,始终把防震减灾工作当作事关人民生命财产安全、经济发展和社会稳定的大事来抓,切实加强对... 详细信息

前言省委、省政府的正确领导下,在省地震局具体指导和大力支持下,张掖市政府和地震局认真贯彻"预防为主,防御与救助相结合"的防震减灾工作方针,始终把防震减灾工作当作事关人民生命财产安全、经济发展和社会稳定的大事来抓,切实加强对全市防震减灾工作的领导,狠抓震害预防、地震应急和灾后重建工作,最大限度减轻地震灾害损失,保障和促进了全市经济社会的可持续发展.

关键词：张掖地震灾害预防重建

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玉门市地震宣传和应急工作

西北地震学报 2005年第4期27卷 397-399页

作者： earthquake administration of Yumen City(earthquake administration of Yumen City,Yumen gansu 735200,china) 玉门市地震局甘肃玉门735200

前言甘肃省玉门市位于河西走廊西端,处在阿尔金山断裂带和祁连山北缘断裂带的交汇地带,境内地质构造复杂,历史上曾经发生过多次破坏性地震,其中包括产生广泛影响的1932年昌马7.6级大地震和2002年青西5.9级地震,近年来被中国地震局和省... 详细信息

前言甘肃省玉门市位于河西走廊西端,处在阿尔金山断裂带和祁连山北缘断裂带的交汇地带,境内地质构造复杂,历史上曾经发生过多次破坏性地震,其中包括产生广泛影响的1932年昌马7.6级大地震和2002年青西5.9级地震,近年来被中国地震局和省地震局确定为地震注意监视区.面对严峻的地震环境和震情趋势,玉门市委、市政府一直十分重视防震减灾工作,坚持以建立健全防震减灾"三大工作体系"为重点,加强领导,精心部署,狠抓落实,在防震减灾宣传和地震应急工作方面积累了一定的经验.

关键词：玉门地震应急地震宣传

Sap-flow measurement and scale transferring from sample trees to entire forest stand of Populus euphratica in desert riparian forest in extreme arid region

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Research in Cold and Arid Regions 2009年第3期1卷 258-266页

作者： JianHua Si 1, Qi Feng 1, HaiYang Xi 1, ZongQiang Chang 1, YongHong Su 1, Kai Zhang 1,2 1. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, lanzhou, gansu 730000, china. 2. Institute of Arid Meteorology, china Meteorological administration, lanzhou, gansu 730020, china. Chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst 320 Donggang West Rd Lanzhou 730000 Gansu Peoples R China china Meteorol Adm Inst Arid Meteorol Lanzhou 730020 Gansu Peoples R China

Understanding how the transpiration of this vegetation type responds to environmental stress is important for determining the wa-ter-balance dynamics of the riparian ecosystem threatened by groundwater depletion. Transpiration and sap flow were measured using the heat-pulse technique. The results were then projected up to the stand level to investigate the stand’s water-use in relation to climate forcing in the desert riparian forest in an extreme arid region. This study took place from April through October 2003 and from May through October 2004. The experimental site was selected in the Populus euphratica Forest Reserve (101o10' E, 41o59' N) in Ejina county, in the lower Heihe River basin, china. The sapwood area was used as a scalar to extrapolate the stand-water consumption from the whole trees’ water consumption measured by the heat-pulse velocity recorder (HPVR). Scale transferring from a series of individual trees to a stand was done according to the existing natural variations between trees under given environmental conditions. The application of the biometric parameters available from individual tree and stand levels was proved suitable for this purpose. A significant correlation between the sapwood area and tree diameter at breast height (DBH) was found. The prediction model is well fitted by the power model. On the basis of the prediction model, the sapwood area can be cal-culated by DBH. The sap-flow density can then be used to extrapolate the stand-water use by means of a series of mathematical models.

关键词： sap flow heat-pulse technique sapwood area scale transferring extreme arid region Populus euphratica

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增值税留抵退税对企业投资的激励效应研究

税务研究 2024年第9期 114-121页

作者：国家税务总局甘肃省税务局课题组于洋吕冰洋牛梦琪不详

增值税留抵退税政策作为近年来大规模税费支持政策的重要内容,对缓解经营主体资金困难、推动企业投资和转型升级具有重要作用。本文基于甘肃省重点税源月度数据和留抵退税数据,采用双重差分方法考察增值税留抵退税政策对企业投资的影响... 详细信息

增值税留抵退税政策作为近年来大规模税费支持政策的重要内容,对缓解经营主体资金困难、推动企业投资和转型升级具有重要作用。本文基于甘肃省重点税源月度数据和留抵退税数据,采用双重差分方法考察增值税留抵退税政策对企业投资的影响。研究发现,增值税留抵退税政策能够有效激励企业投资,对制造业企业、小微企业、民营企业和初创企业等的投资激励效应尤为明显。留抵退税制度可从以下三方面进行完善:一是完善留抵退税制度设计,实施差异化留抵退税;二是健全留抵退税分担机制,保障各地负担公平;三是强化退税风险监管,严厉打击骗税行为。

关键词：增值税留抵退税税收优惠企业投资减税降费

Analysis on a Cold Wave Weather Process in Winter in gansu

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Meteorological and Environmental Research 2011年第11期2卷 25-28页

作者： SUN Yu-lian 1,2,ZHANG Shu-fang 2,ZHANG Li-lu 3,HUANG Cheng-xiu 2,HE Yu-chun 2 1.lanzhou Institute of Arid Meteorology,china Meteorological administration,lanzhou 730020,china 2.Linxia Meteorological Bureau in gansu,Linxia 731100,china 3.Yongjing Meteorological Bureau in Linxia of gansu,Yongjing 731600,china

[Objective]The research aimed to analyze a cold wave weather process in winter in gansu.[Method] Based on routine observation data and numerical forecast products,formation reason and physical quantity characteristics of a cold wave process during 2-5 December,2008 were comprehensively analyzed by synoptic analysis and diagnostic analysis methods.[Result]The cold wave weather belonged to ' translot turning vertical type'.Collapse of the Urals ridge,turning vertical of the translot and strengthening south of the ground cold high induced the cold *** of the Siberian low vortex drove the small branch of cold air in polar region supplementing south,playing certain promoting role in outbreak of the cold *** quantities in the cold wave process also had very good expression,such as vorticity,temperature advection,etc.[Conclusion]This research had important indication effect for early warning,forecast and decision service of the future similar weather process.

关键词： Cold wave Physical quantity characteristics Formation reason gansu china