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Vegetation and climate change during Marine Isotope Stage 3 in China 被引量:2
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作者 Yan Zhao Zicheng Yu +5 位作者 Ulrike Herzschuh Bao Yang Hui Zhao Keyan Fang Huan Li Quan Li 《Chinese Science Bulletin》 SCIE EI CAS 2014年第33期4444-4455,共12页
Fossil pollen records from 45 sites across China were evaluated and synthesized to document vegetation and climate change during Marine Isotope Stage 3(MIS 3)at 60–27 ka and to understand the large-scale controls.Dur... Fossil pollen records from 45 sites across China were evaluated and synthesized to document vegetation and climate change during Marine Isotope Stage 3(MIS 3)at 60–27 ka and to understand the large-scale controls.During MIS3, vegetation type was dominantly forest in eastern China, forest steppe/meadow in the north and Tibetan Plateau, and steppe desert in northwestern arid China. We developed a semi-quantitative vegetation index to reflect change in plant abundance(by inferring the general climate conditions), with a vegetation score from 1to 3 based on the different vegetation types inferred from pollen data at individual sites at intervals of 2,000 years.The reconstructed vegetation index shows higher values during MIS 3, especially during the period 53–40 ka, than at the Last Glacial Maximum. Our results also suggest that climate on the basis of vegetation change was cooler and drier during MIS 3 than during the Holocene optimum;however, MIS 3 vegetation was probably similar to modern vegetation. The close relationship between vegetation change, insolation and Asian summer monsoon strength suggests that climate variations, probably in both temperature and precipitation, are the primary drivers of regional vegetation change. Additional well-dated, high-resolution palaeoclimate records from many locations across China will be needed to understand the vegetation change and climate forcings on millennial and centennial scales within MIS 3. 展开更多
关键词 深海氧同位素 植被类型 气候变化 中国海洋 草原化荒漠 植被变化 中国东部地区 森林草原
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TBtools: An Integrative Toolkit Developed for Interactive Analyses of Big Biological Data 被引量:1302
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作者 Chengjie Chen Hao Chen +4 位作者 Yi Zhang Hannah R.Thomas Margaret H.Frank Yehua He Rui Xia 《Molecular Plant》 SCIE CAS CSCD 2020年第8期1194-1202,共9页
The rapid development of high-throughput sequencing techniques has led biology into the big-data era.Data analyses using various bioinformatics tools rely on programming and command-line environments,which are challen... The rapid development of high-throughput sequencing techniques has led biology into the big-data era.Data analyses using various bioinformatics tools rely on programming and command-line environments,which are challenging and time-consuming for most wet-lab biologists.Here,we present TBtools(a Toolkit for Biologists integrating various biological data-handling tools),a stand-alone software with a userfriendly interface.The toolkit incorporates over 130 functions,which are designed to meet the increasing demand for big-data analyses,ranging from bulk sequence processing to interactive data visualization.A wide variety of graphs can be prepared in TBtools using a new plotting engine("JIGplot")developed to maximize their interactive ability;this engine allows quick point-and-click modification of almost every graphic feature.TBtools is platform-independent software that can be run under all operating systems with Java Runtime Environment 1.6 or newer.It is freely available to non-commercial users at https://github.com/CJ-Chen/TBtools/releases. 展开更多
关键词 TBtools BIOINFORMATICS big data data visulization gene family
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Characterization of microRNAs in serum: a novel class of biomarkers for diagnosis of cancer and other diseases 被引量:985
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作者 Xi Chen Yi Ba +26 位作者 Lijia Ma Xing Cai Yuan Yin Kehui Wang Jig ang Guo Yujing Zhang Jiangning Chen Xing Guo Qibin Li Xiaoying Li Wenjing Wang Yan Zhang Jin Wang Xueyuan Jiang Yang Xiang Chen Xu Pingping Zheng Juanbin Zhang Ruiqiang Li Hongjie Zhang Xiaobin Shang Ting Gong Guang Ning Jun Wang Ke Zen Junfeng Zhang Chen-Yu Zhang 《Cell Research》 SCIE CAS CSCD 2008年第10期997-1006,共10页
Dysregulated expression of microRNAs (miRNAs) in various tissues has been associated with a variety of diseases, including cancers. Here we demonstrate that miRNAs are present in the serum and plasma of humans and o... Dysregulated expression of microRNAs (miRNAs) in various tissues has been associated with a variety of diseases, including cancers. Here we demonstrate that miRNAs are present in the serum and plasma of humans and other animals such as mice, rats, bovine fetuses, calves, and horses. The levels of miRNAs in serum are stable, reproducible, and consistent among individuals of the same species. Employing Solexa, we sequenced all serum miRNAs of healthy Chinese subjects and found over 100 and 91 serum miRNAs in male and female subjects, respectively. We also identified specific expression patterns of serum miRNAs for lung cancer, colorectal cancer, and diabetes, providing evidence that serum miRNAs contain fingerprints for various diseases. Two non-small cell lung cancer-specific serum miRNAs obtained by Solexa were further validated in an independent trial of 75 healthy donors and 152 cancer patients, using quantitative reverse transcription polymerase chain reaction assays. Through these analyses, we conclude that serum miRNAs can serve as potential biomarkers for the detection of various cancers and other diseases. 展开更多
关键词 serum-microRNA expression profile FINGERPRINT blood-based biomarker Solexa CANCERS diabetes
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Evolution of the novel coronavirus from the ongoing Wuhan outbreak and modeling of its spike protein for risk of human transmission 被引量:782
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作者 Xintian Xu Ping Chen +5 位作者 Jingfang Wang Jiannan Feng Hui Zhou Xuan Li Wu Zhong Pei Hao 《Science China(Life Sciences)》 SCIE CAS CSCD 2020年第3期457-460,共4页
Dear Editor,The occurrence of concentrated pneumonia cases in Wuhan city,Hubei province of China was first reported on December 30,2019 by the Wuhan Municipal Health Commission(WHO,2020).The pneumonia cases were found... Dear Editor,The occurrence of concentrated pneumonia cases in Wuhan city,Hubei province of China was first reported on December 30,2019 by the Wuhan Municipal Health Commission(WHO,2020).The pneumonia cases were found to be linked to a large seafood and animal market in Wuhan,and measures for sanitation and disinfection were taken swiftly by the local government agency.The Centers for Disease Control and Prevention(CDC)and Chinese health authorities later determined and announced that a novel coronavirus(CoV),denoted as 2019-nCoV,had caused the pneumonia outbreak in Wuhan city(CDC,2020).Scientists from multiple groups had obtained the virus samples from hospitalized patients(Normile,2020).The isolated viruses were morphologically identical when observed under electron microscopy. 展开更多
关键词 WUHAN EVOLUTION measures
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Future Physics Programme of BESⅢ 被引量:543
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作者 M.Ablikim M.N.Achasov +147 位作者 P.Adlarson S.Ahmed M.Albrecht M.Alekseev A.Amoroso F.F.An Q.An Y.Bai O.Bakina R.Baldini Ferroli Y.Ban K.Begzsuren J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi J Biernat J.Bloms I.Boyko R.A.Briere L.Calibbi H.Cai X.Cai A.Calcaterra G.F.Cao N.Cao S.A.Cetin J.Chai J.F.Chang W.L.Chang J.Charles G.Chelkov Chen G.Chen H.S.Chen J.C.Chen M.L.Chen S.J.Chen Y.B.Chen H.Y.Cheng W.Cheng G.Cibinetto F.Cossio X.F.Cui H.L.Dai J.P.Dai X.C.Dai A.Dbeyssi D.Dedovich Z.Y.Deng A.Denig Denysenko M.Destefanis S.Descotes-Genon F.De Mori Y.Ding C.Dong J.Dong L.Y.Dong M.Y.Dong Z.L.Dou S.X.Du S.I.Eidelman J.Z.Fan J.Fang S.S.Fang Y.Fang R.Farinelli L.Fava F.Feldbauer G.Felici C.Q.Feng M.Fritsch C.D.Fu Y.Fu Q.Gao X.L.Gao Y.Gao Y.Gao Y.G.Gao Z.Gao B.Garillon I.Garzia E.M.Gersabeck A.Gilman K.Goetzen L.Gong W.X.Gong W.Gradl M.Greco L.M.Gu M.H.Gu Y.T.Gu A.Q.Guo F.K.Guo L.B.Guo R.P.Guo Y.P.Guo A.Guskov S.Han X.Q.Hao F.A.Harris K.L.He F.H.Heinsius T.Held Y.K.Heng Y.R.Hou Z.L.Hou H.M.Hu J.F.Hu T.Hu Y.Hu G.S.Huang J.S.Huang X.T.Huang X.Z.Huang Z.L.Huang N.Huesken T.Hussain W.Ikegami Andersson W.Imoehl M.Irshad Q.Ji Q.P.Ji X.B.Ji X.L.Ji H.L.Jiang X.S.Jiang X.Y.Jiang J.B.Jiao Z.Jiao D.P.Jin S.Jin Y.Jin T.Johansson N.Kalantar-Nayestanaki X.S.Kang R.Kappert M.Kavatsyuk B.C.Ke I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L. 《Chinese Physics C》 SCIE CAS CSCD 2020年第4期I0001-I0004,1-102,共106页
There has recently been a dramatic renewal of interest in hadron spectroscopy and charm physics. This renaissance has been driven in part by the discovery of a plethora of charmonium-like XYZ states at BESⅢ and B fac... There has recently been a dramatic renewal of interest in hadron spectroscopy and charm physics. This renaissance has been driven in part by the discovery of a plethora of charmonium-like XYZ states at BESⅢ and B factories, and the observation of an intriguing proton-antiproton threshold enhancement and the possibly related X(1835) meson state at BESⅢ, as well as the threshold measurements of charm mesons and charm baryons. We present a detailed survey of the important topics in tau-charm physics and hadron physics that can be further explored at BESⅢ during the remaining operation period of BEPCⅡ. This survey will help in the optimization of the data-taking plan over the coming years, and provides physics motivation for the possible upgrade of BEPCⅡ to higher luminosity. 展开更多
关键词 MESON HADRON optimization
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DCT域图像水印:嵌入对策和算法 被引量:292
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作者 黄继武 Yun Q.SHI 程卫东 《电子学报》 EI CAS CSCD 北大核心 2000年第4期57-60,共4页
DCT域的隐形水印应嵌入哪里 ,水印才足够稳健 ?尽管许多关于DCT域水印算法的文献赞成水印应放在对视觉效果重要的分量 ,但DC分量总是被无一例外地排除在外 .本文提出了一个DCT域隐形水印的嵌入对策和一个应用该对策的自适应水印算法 .... DCT域的隐形水印应嵌入哪里 ,水印才足够稳健 ?尽管许多关于DCT域水印算法的文献赞成水印应放在对视觉效果重要的分量 ,但DC分量总是被无一例外地排除在外 .本文提出了一个DCT域隐形水印的嵌入对策和一个应用该对策的自适应水印算法 .基于对图像DCT系数振幅的定量分析 ,我们指出 :DC分量比任何AC分量有更大的感觉容量 ,从稳健性的角度 ,DC分量最适合用来嵌入水印 .应用这个对策 ,本文提出了一个把视觉系统纹理掩蔽特性结合到水印编码过程的自适应水印算法 .实验结果有效地支持了这个结论 ,所产生的隐形水印体现了很好的稳健性 . 展开更多
关键词 图像水印 嵌入对策 DCT域 加密算法
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SHEsis,a powerful software platform for analyses of linkage disequilibrium,haplotype construction,and genetic association at polymorphism loci 被引量:386
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作者 Yong Yong SHI Lin HE 《Cell Research》 SCIE CAS CSCD 2005年第2期97-98,共2页
In multiloci-based genetic association studies of complex diseases, a powerful and high efficient tool for analyses oflinkage disequilibrium (LD) between markers, haplotype distributions and many chi-square/p values w... In multiloci-based genetic association studies of complex diseases, a powerful and high efficient tool for analyses oflinkage disequilibrium (LD) between markers, haplotype distributions and many chi-square/p values with a large numberof samples has been sought for long. In order to achieve the goal of obtaining meaningful results directly from raw data,we developed a robust and user-friendly software platform with a series of tools for analysis in association study withhigh efficiency. The platform has been well evaluated by several sets of real data. 展开更多
关键词 SOFTWARE linkage disequilibrium haplotype analysis genetic association study.
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Data Processing System (DPS) software with experimental design, statistical analysis and data mining developed for use in entomological research 被引量:364
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作者 Qi-Yi Tang Chuan-Xi Zhang 《Insect Science》 SCIE CAS CSCD 2013年第2期254-260,共7页
A comprehensive but simple-to-use software package called DPS (Data Pro- cessing System) has been developed to execute a range of standard numerical analyses and operations used in experimental design, statistics an... A comprehensive but simple-to-use software package called DPS (Data Pro- cessing System) has been developed to execute a range of standard numerical analyses and operations used in experimental design, statistics and data mining. This program runs on standard Windows computers. Many of the functions are specific to entomological and other biological research and are not found in standard statistical sottware. This paper presents applications of DPS to experimental design, statistical analysis and data mining in entomology. 展开更多
关键词 data mining DPS entomological research experimental design software statistical analysis
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Measurements of dihadron correlations relative to the event plane in Au+Au collisions at√^(S)NN=200 GeV 被引量:351
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作者 H.Agakishiev M.M.Aggarwal +140 位作者 Z.Ahammed A.V.Alakhverdyants I.Alekseev J.Alford B.D.Anderson C.D.Anson D.Arkhipkin G.S.Averichev J.Balewski D.R.Beavis N.K.Behera R.Bellwied M.J.Betancourt R.R.Betts A.Bhasin A.K.Bhat H.Bichsel J.Bieleik J.Bielcikova B.Biritz L.C.Bland W.Borowski J.Bouchet E.Braidot A.V.Brandin A.Bridgeman S.G.Brovko E.Bruna S.Bueltmann I.Bunzarov T.P.Burton X.Z.Cai H.Caines M.Calderon de la Barca Sanchez D.Cebra R.Cendejas M.C.Cervantes Z.Chajecki P.Chaloupka S.Chattopadhyay H.F.Chen J.H.Chen J.Y.Chen L.Chen J.Cheng M.Cherney A.Chikanian K.E.Choi W.Christie P.Chung M.J.M.Codrington R.Corliss J.G.Cramer H.J.Crawford S.Dash A.Davila Leyva L.C.De Silvat R.R.Debbe T.G.Dedovich A.A.Derevschikov R.Derradi de Souza L.Didenko P.Djawotho S.M.Dogra X.Dong J.L.Drachenberg J.E.Draper J.C.Dunlop L.G Efimov M.Elnim J.Engelage G Eppley M.Estienne L.Eun O.Evdokimov R.Fatemi J.Fedorisin A.Feng R.G.Fersch P.Filip E.Finch V.Fine Y.Fisyak C.A.Gagliardi D.R.Gangadharan A.Geromitsos F.Geurts P.Ghosh Y.N.Gorbunov A.Gordon O.Grebenyuk D.Grosnick S.M.Guertin A.Gupta W.Guryn B.Haag O.Hajkova A.Hamed L-X.Han J.W.Harris J.P.Hays-Wehle M.Heinz S.Heppelmann A.Hirsch E.Hjort G.W.Hoffmann D.J.Hofiman B.Huang H.Z.Huang T.J.Humanic L.Huo G.Igo P.Jacobs W.W.Jacobs C.Jena F.Jin J.Joseph E.G.Judd S.Kabana K.Kang J.Kapitan K.Kauder H.Ke D.Keane A.Kechechyan D.Kettler D.P.Kikola J.Kiryluk A.Kisiel V.Kizka A.G.Knospe D.D.Koetke T.Kollegger J.Konzer I.Koralt L.Koroleva W.Korsch L.Kotchenda V.Kouchpil P.Kravtsov K.Krueger 《Chinese Physics C》 SCIE CAS CSCD 2021年第4期198-241,共44页
Dihadron azimuthal correlations containing a high transverse momentum(pr)trigger particle are sensit-ive to the properties of the nuclear medium created at RHIC through the strong interactions occurring between the tr... Dihadron azimuthal correlations containing a high transverse momentum(pr)trigger particle are sensit-ive to the properties of the nuclear medium created at RHIC through the strong interactions occurring between the traversing parton and the medium,ie.jet-quenching.Previous measurements revealed a strong modification to di-hadron azimuthal correlations in Au+Au collisions with respect to ptp and d+Au collisions.The modification in-creases with the collision centrality,suggesting a path-length or energy density dependence to the je-quenching ef-fect.This paper reports STAR measurements of dihadron azimuthal correlations in mid-central(20%-60%)Au+Au collisions at√^(S)NN=200 GeV as a function of the trigger particle's azimuthal angle relative to the event plane,Ф_(s)=|Ф_(t)-ψ_(Ep)|.The azimuthal correlation is studied as a function of both the trigger and associated particle pr.The subtractions of the combinatorial background and anisotropic flow,assuming Zero Yield At Minimum(ZYAM),are described.The correlation results are first discussed with subtraction of the even harmonic(elliptic and quadrangu-lar)flow backgrounds.The away-side correlation is strongly modifed,and the modification varies withФ_(s),with a double-peak structure for out-of-plane trigger particles.The near-side ridge(long range pseudo-rapidity△_(η)correla-tion)appears to drop with increasingФ_(s)while the jet-like component remains approximately constant.The correla-tion functions are further studied with the subtraction of odd harmonic triangular flow background arising from fluc-tuations.It is found that the triangular flow,while responsible for the majority of the amplitudes,is not sufficient to explain theφs-dependence of the ridge or the away-side double-peak structure.The dropping ridge withФ_(s)could be attributed to aФ_(s)-dependent lliptie anisotropy;however,the physics mechanism of the ridge remains an open ques-tion.Even with aФ_(s)-dependent elliptic flow,the away-side correlation structure is robust.These results,with exte 展开更多
关键词 relativistic heavy ion collisions dihadron correlations jet-medium interactions anisotropic flow background event plane
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CONSORT 2010说明与详述:报告平行对照随机临床试验指南的更新 被引量:348
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作者 David Moher Sally Hopewell +9 位作者 Kenneth F Schulz Victor Montori Peter C Gφtzsche P J Devereaux Diana Elbourne Matthias Egger Douglas G Altman 周庆辉 卞兆祥 刘建平 《中西医结合学报》 CAS 2010年第8期701-741,共41页
大量证据显示随机对照临床试验(randomised controlled trial,RCT)的报告质量不理想。报告不透明,则读者既不能评判试验结果是否真实可靠,也不能从中提取可用于系统综述的信息。最近的方法学分析表明,报告不充分和设计不合理与对治疗效... 大量证据显示随机对照临床试验(randomised controlled trial,RCT)的报告质量不理想。报告不透明,则读者既不能评判试验结果是否真实可靠,也不能从中提取可用于系统综述的信息。最近的方法学分析表明,报告不充分和设计不合理与对治疗效果产生评价偏倚有关。这种系统误差对RCT损害严重,而RCT正是以其能减少或避免偏倚而被视为评价干预措施的金标准。为了提高RCT的报告质量,一个由专家和编辑组成的工作组制定了临床试验报告的统一标准(Consolidated Standards of Reporting Trials,CONSORT)声明。CONSORT声明于1996年首次发表,并于2001年更新。声明由对照检查清单和流程图组成,供作者在报告RCT时使用。许多核心医学期刊和主要国际性编辑组织都已认可CONSORT声明。该声明促进了对RCT的严格评价和解释。2001年,在对CONSORT进行修订时,人们就已经清楚地认识到,解释和说明制定CONSORT声明的原理,有助于研究人员等撰写或评价临床试验报告。一篇CONSORT说明与详述文章于2001年同2001版CONSORT声明一起发表。2007年1月的专家会议之后,对CONSORT声明作了进一步修订并已发表,即"CONSORT2010声明"。这次更新对原版对照检查清单作了文字上的修改,使其更为明晰,并收入了与一些新近才认识到的主题相关的建议,如选择性报告结局产生的偏倚。说明与详述文件旨在加强人们对CONSORT声明的理解、应用和传播,这次也作了大量修订,对每一项新增或更新的清单条目的含义和增改理由进行了解释,提供了优秀的报告实例,还尽可能地提供了相关的经验性研究的参考文献。文中收入了若干流程图实例。"CONSORT2010声明"、其说明与详述文件,以及相关网站(www.consort-statement.org),对于改进随机临床试验报告必将有所裨益。 展开更多
关键词 临床试验 随机对照试验 指南 CONSORT
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极高强度他汀治疗对冠状动脉粥样硬化消退的影响——ASTEROID试验 被引量:347
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作者 Steven E. Nissen Stephen J. Nicholls +16 位作者 Ilks Sipahi Peter Libby Joel S. Raichlen Christie M. Ballantyne Jean Davignon Raimund Erbel Jean Charles Fruchart Jean-Claude Tardif Paul Schoenhagen Tim Crowe Valerie Cain Kathy Wolski Marlene Coormastic E. Murat Tuzcu 仝其广(译) 王淑敏(译) 胡大一(校) 《美国医学会杂志(中文版)》 2006年第4期215-223,共9页
背景:以前的血管内超声(intravascular ultrasound,IVUS)试验证实,他汀治疗可减缓或阻止动脉粥样硬化的进展,但是迄今尚无应用动脉粥样斑块体积百分比(percent atheroma volume,PAV)证实粥样硬化消退的确切证据。PAV是最严格... 背景:以前的血管内超声(intravascular ultrasound,IVUS)试验证实,他汀治疗可减缓或阻止动脉粥样硬化的进展,但是迄今尚无应用动脉粥样斑块体积百分比(percent atheroma volume,PAV)证实粥样硬化消退的确切证据。PAV是最严格的评价病变进展和消退的IVUS测量指标。 目标:评价极高强度他汀治疗是否能逆转IVUS确定的冠状动脉粥样硬化。 设计和地点:于美国、加拿大、欧洲和澳大利亚53个社区和3级保健中心进行前瞻性开标盲法终点试验(A Study to Evaluate the Effect of Rosuvastatin on Intravascular Ultrasound-Derived Coronary Atheroma Burden,ASTEROID)。应用马达驱动回撤IVUS评价基线和治疗24个月时冠状动脉粥样斑块负荷。每对基线和随访IVUS测量结果均进行盲法分析。 病例:从2002年11月到2003年10月,507例患者有基线IVUS检查结果,并接受至少1个剂量的研究药物。在24个月后,349例患者具有可用于评估的系列IVUS检查结果。 干预:所有患者均接受瑞舒伐他汀40ms/d强化治疗。 主要观测指标:预先设定了两个一级疗效指标:PAV变化和基线最严重病变10min节段动脉粥样斑块体积变化。二级疗效指标为整个动脉标准化总斑块体积的变化。结果:平均(SD)LDL—C水平由基线时的130.4(34.3)ms/dL降至60.8(20.0)ms/扎,平均下降了53.2%(P〈0.001)。平均(SD)HDL-C水平从基线时的43.1(11.1)ms/dL升至49.0(12.6)ms/dL,平均增加了14.7%(P〈0.001)。整个血管PAV平均(SD)变化为-0.98%(3.15%),中位数为-0.79%(97.5%CI,-1.21%~-0.53%)(与基线比较,P〈0.001)。最严重病变10min节段斑块体积平均(SD)变化为-6.1(10.1)mm^3,中位数为-5.6mm^3(97.5%CI,-6.8~-4.0mm^3)(与基线比较,P〈0.001)。总斑块体积变化中位数降低了6.8%,� 展开更多
关键词 冠状动脉粥样硬化 瑞舒伐他汀 强化治疗 斑块消退 冠状动脉粥样斑块 INTRAVASCULAR 试验 强度 ROSUVASTATIN 冠心病患者
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再论南岭燕山早期花岗岩的成因类型与构造意义 被引量:305
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作者 李献华 李武显 李正祥 《科学通报》 EI CAS CSCD 北大核心 2007年第9期981-991,共11页
中国东南部南岭地区广泛出露的燕山早期(侏罗纪)花岗岩与稀有金属成矿作用有非常密切的关系,这些花岗岩以弱过铝质黑云母二长花岗岩和黑云母钾长花岗岩为主,并和一些规模较小的含角闪石花岗岩和含白云母±石榴子石的浅色花岗岩在时... 中国东南部南岭地区广泛出露的燕山早期(侏罗纪)花岗岩与稀有金属成矿作用有非常密切的关系,这些花岗岩以弱过铝质黑云母二长花岗岩和黑云母钾长花岗岩为主,并和一些规模较小的含角闪石花岗岩和含白云母±石榴子石的浅色花岗岩在时-空上密切共生.在以往的文献中,这些黑云母花岗岩一般被认为是陆壳改造型(相当于S型)花岗岩,是区域元古代变质沉积岩重熔的产物.对南岭燕山早期一些代表性花岗岩的岩石化学特征和SiO2-P2O5相关关系进行了系统的分析研究,结果显示这些花岗岩的SiO2-P2O5均呈明显的负相关关系,表明南岭燕山早期的含角闪石花岗闪长岩-黑云母二长花岗岩-黑云母钾长花岗岩-二(白)云母花岗岩为准铝质-弱过铝质的I型/分异I型花岗岩演化系列,其源岩主要为元古代火成岩,少量新生地壳和/或地幔分异物质很可能参与了花岗岩的形成.同时,这些I型/分异I型花岗岩在时空上和A型酸性、基性火山/侵入岩以及碱性岩密切共生,构成了一个比较典型的板内非造山火成岩组合,反映了燕山早期南岭及邻区大陆岩石圈以伸展背景为主. 展开更多
关键词 花岗岩 成因分类 燕山早期 南岭 华南 岩石圈伸展
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高质量发展背景下的现代化经济体系建设:一个逻辑框架 被引量:300
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作者 高培勇 杜创 +2 位作者 刘霞辉 袁富华 汤铎铎 《经济研究》 CSSCI 北大核心 2019年第4期4-17,共14页
本文以经济体系为核心概念,综合运用政治经济学、微观经济学与宏观经济学方法,建立一个逻辑框架,阐述现代化经济体系建设的理论逻辑。主要结论如下:(1)建设现代化经济体系本质上是经济体系转换的过程,即从传统经济体系转换到现代化经济... 本文以经济体系为核心概念,综合运用政治经济学、微观经济学与宏观经济学方法,建立一个逻辑框架,阐述现代化经济体系建设的理论逻辑。主要结论如下:(1)建设现代化经济体系本质上是经济体系转换的过程,即从传统经济体系转换到现代化经济体系;具体包括"四个转向":社会主要矛盾、资源配置方式、产业体系、增长阶段等方面的特征性变化。(2)与"四个转向"相对应,现代化经济体系运转体现为"四个机制",即社会主要矛盾的性质决定了资源配置方式的选择,资源配置方式决定产业体系特征,产业体系特征与经济增长阶段一致,高速增长引起社会主要矛盾转化。上述结果表明,现代化经济体系建设是社会经济系统的综合转型,是中国经济走向高质量发展的必由之路。 展开更多
关键词 经济体系 社会主要矛盾 资源配置方式 产业体系 增长阶段
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The Influence of ENSO on the Summer Climate Change in China and Its Mechanism 被引量:289
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作者 黄荣辉 吴仪芳 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1989年第1期21-32,共12页
The influence of ENSO on the summer climate change in China and its mechanism from the observed data is discussed. It is discovered that in the developing stage of ENSO, the SST in the western tropical Pacific is col... The influence of ENSO on the summer climate change in China and its mechanism from the observed data is discussed. It is discovered that in the developing stage of ENSO, the SST in the western tropical Pacific is colder in summer, the convective activities may be weak around the South China Sea and the Philippines. As a consequence, the subtropical high shifted southward. Therefore, a drought may be caused in the Indo-China peninsula and in the South China. Moreover, in midsummer the subtropical high is weak over the Yangtze River valley and Huaihe River valley, and the flood may be caused in the area from the Yangtze River valley to Huaihe River valley. On the contrary, in the decaying stage of ENSO. the convective activities may be strong around the Philippines, and the subtropical high shifted northward, a drought may be caused in the Yangtze River valley and Huaihe River valley. 展开更多
关键词 The Influence of ENSO on the Summer Climate Change in China and Its Mechanism ENSO
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DREB转录因子在提高植物抗逆性中的作用 被引量:176
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作者 刘强 赵南明 +1 位作者 K.Yamaguch-Shinozaki K.Shinozaki 《科学通报》 EI CAS CSCD 北大核心 2000年第1期11-16,共6页
拟南芥rd29A基因编码一种与LEA蛋白相似的亲水性很强的蛋白,该基因的表达受干旱、高盐及低温的诱导.rd29A基因启动子区域中,有两个与上述环境胁迫应答有关的DRE顺式作用元件.利用 rd29A基因启动子的 DRE ... 拟南芥rd29A基因编码一种与LEA蛋白相似的亲水性很强的蛋白,该基因的表达受干旱、高盐及低温的诱导.rd29A基因启动子区域中,有两个与上述环境胁迫应答有关的DRE顺式作用元件.利用 rd29A基因启动子的 DRE 顺式作用元件和酵母 One-Hybrid方法,两类(共 5个)与DRE元件特异结合、在低温或干旱、高盐胁迫条件下调控报道基因表达的拟南芥DREB转录因子被克隆及鉴定,分别定名为 DREB1A~C和 DREB2A~B. DREB转录因子和 DRE元件在干旱、高盐及低温胁迫信号传递中起重要作用.一个DREB转录因子可以调控多个与植物干旱、高盐及低温耐性有关的功能基因的表达.因此,利用转录因子来改良植物抗逆性,能获得较为理想的综合效果。 展开更多
关键词 DREB 转录因子 基因表达调控 植物 抗逆性
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Spatiotemporal characteristics, patterns, and causes of land-use changes in China since the late 1980s 被引量:271
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作者 LIU Jiyuan KUANG Wenhui +13 位作者 ZHANG Zengxiang XU Xinliang QIN Yuanwei NING Jia ZHOU Wancun ZHANG Shuwen LI Rendong YAN Changzhe WU Shixin SHI Xuezheng JIANG Nan YU Dongsheng PAN Xianzhang CHI Wenfeng 《Journal of Geographical Sciences》 SCIE CSCD 2014年第2期195-210,共16页
Land-use/land-cover changes (LUCCs) have links to both human and nature inter- actions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year inter- vals from the late 1980s to 2010, with stand... Land-use/land-cover changes (LUCCs) have links to both human and nature inter- actions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year inter- vals from the late 1980s to 2010, with standard procedures based on Landsat TM/ETM+ im- ages. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics, differences, and causes of land-use changes at a national scale were then examined. The main findings are summarized as fol- lows. Land-use changes (LUCs) across China indicated a significant variation in spatial and temporal characteristics in the last 20 years (1990-2010). The area of cropland change de- creased in the south and increased in the north, but the total area remained almost un- changed. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly, were mainly distributed in the east, and gradually spread out to central and western China. Woodland decreased first, and then increased, but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included (1) an accelerated expansion of built-up land in the Huang-Huai-Hai region, the southeastern coastal areas, the midstream area of the Yangtze River, and the Sichuan Basin; (2) shifted land reclamation in the north from northeast China and eastern Inner Mongolia to the oasis agricultural areas in northwest China; (3) continuous transformation from rain-fed farmlands in northeast China to paddy fields; and (4) effective- ness of the "Grain for Green" project in the southern agricultural-pastoral ecotones of Inner Mongolia, the Loess Plateau, and southwestern mountainous areas. In the last two decades, although climate change 展开更多
关键词 satellite remote sensing land-use change CHARACTERISTICS spatial pattern China
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Active tectonic blocks and strong earthquakes in the continent of China 被引量:262
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作者 ZHANG Peizhen (张培震) DENG Qidong (邓起东) ZHANG Guomin (张国民) MA Jin (马 瑾) GAN Weijun (甘卫军) MIN Wei (闵 伟) MAO Fengying (毛凤英) WANG Qi (王 琪) 《Science China Earth Sciences》 SCIE EI CAS 2003年第z2期13-24,共12页
The primary pattern of the late Cenozoic to the present tectonic deformation of China is characterized by relative movements and interactions of tectonic blocks. Active tectonic blocks are geological units that have b... The primary pattern of the late Cenozoic to the present tectonic deformation of China is characterized by relative movements and interactions of tectonic blocks. Active tectonic blocks are geological units that have been separated from each other by active tectonic zones. Boundaries between blocks are the highest gradient of differential movement. Most of tectonic activity occurs on boundaries of the blocks. Earthquakes are results of abrupt releases of accumulated strain energy that reaches the threshold of strength of the earth's crust. Boundaries of tectonic blocks are the locations of most discontinuous deformation and highest gradient of stress accumulation, thus are the most likely places for strain energy accumulation and releases, and in turn, devastating earthquakes. Almost all earthquakes of magnitude greater than 8 and 80%-90% of earthquakes of magnitude over 7 occur along boundaries of active tectonic blocks. This fact indicates that differential movements and interactions of active tectonic blocks are the primary mechanism for the occurrences of devastating earthquakes. 展开更多
关键词 active TECTONIC block interactions of blocks differential movement STRONG EARTHQUAKE activity.
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森林细根生产和周转研究 被引量:210
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作者 张小全 吴可红 《林业科学》 EI CAS CSCD 北大核心 2001年第3期126-138,共13页
随着近 2 0多年来对细根功能的深入认识和研究方法的发展 ,林分细根生物量、生产和周转及其与环境因子的关系成为森林生态学的研究热点之一 ,开展了大量研究。本文在收集了大量研究报道基础上 ,对森林细根研究结果进行综述。结果如下 :... 随着近 2 0多年来对细根功能的深入认识和研究方法的发展 ,林分细根生物量、生产和周转及其与环境因子的关系成为森林生态学的研究热点之一 ,开展了大量研究。本文在收集了大量研究报道基础上 ,对森林细根研究结果进行综述。结果如下 :细根 (直径 <2~ 5mm)生物量变化在 46~ 2 80 5g·m- 2 之间 ,大部分在 10 0~ 10 0 0g·m- 2 ;细根生物量分别占地下部分总生物量和林分总生物量的 3%~ 30 %和 0 .5 %~ 10 % ;北方常绿针叶林平均细根生物量最低 (2 16g·m- 2 ) ,热带常绿阔叶林最高 (10 87g·m- 2 )。细根年净生产量 2 0~ 1317g·m- 2 ·a- 1 ,占林分总净初级生产量的3%~ 84% ,大部分在 10 %~ 6 0 % ;从北方森林到温带、亚热带至热带森林 ,细根生产量呈增加趋势 ;针叶林细根生产在总净初级生产中的比例小于阔叶林 (常绿和落叶 )。树木细根生命周期短至数天 ,长达数年。细根年周转率 4.3%~ 2 73.2 % ,阔叶林细根周转率低于针叶林。细根生产和周转是土壤碳和养分的重要来源 ,细根生产向林地输入的生物量占总输入 (细根生产和地上枯落物输入 )的 6 .2 %~ 88.7%。除气候森林类型外 ,森林生态系统细根生物量、分布、生产、周转还因季节、土壤类型、立地条件和生长发育阶段而异。同时 。 展开更多
关键词 森林生态学 细根 生物量 生产 生命周期 周转
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Determination of U-Pb age and rare earth element concentrations of zircons from Cenozoic intrusions in northeastern China by laser ablation ICP-MS 被引量:260
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作者 YUAN Honglin WU Fuyuan +3 位作者 GAO Shan LIU Xiaoming XU Ping SUN Deyou 《Chinese Science Bulletin》 SCIE EI CAS 2003年第22期2411-2421,共11页
Using the in situ zircon U-Pb dating method of LA-ICPMS, we analyzed the 31 Ma old SHRIMP U-Pb age of the Yongsheng nepheline syenite from southern Jilin Province under different spot sizes. The obtained ages are comp... Using the in situ zircon U-Pb dating method of LA-ICPMS, we analyzed the 31 Ma old SHRIMP U-Pb age of the Yongsheng nepheline syenite from southern Jilin Province under different spot sizes. The obtained ages are comparable with that of SHRIMP in both accuracy and precision. The age is also identical to that of the Yinmawanshan gabbro from the Liaodong Peninsula within error. Both the Yongsheng nepheline syenite and the Yinmawanshan gabbro represent the youngest known exposed intrusions in northeastern and even eastern China. The results indicate the Eocene mantle-derived magmatic underplating, and the rapid crustal uplifting of this region since 30 Ma. The analyses also document extremely high LREE concentrations and relatively flat REE patterns for the zircons from the Yongsheng nepheline syenite, which represent a new type of zircon REE pattern. 展开更多
关键词 Pb 锆石 中国 东北地区 地球年代学
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Resource diversity of Chinese macrofungi:edible,medicinal and poisonous species 被引量:259
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作者 Fang Wu Li-Wei Zhou +3 位作者 Zhu-Liang Yang Tolgor Bau Tai-Hui Li Yu-Cheng Dai 《Fungal Diversity》 SCIE 2019年第5期1-76,共76页
The huge land areas in China provide highly diverse habitats for macrofungi.Of these macrofungi,many are directly related to people’s daily life and have been utilized by ancient Chinese for at least 6800 years.In th... The huge land areas in China provide highly diverse habitats for macrofungi.Of these macrofungi,many are directly related to people’s daily life and have been utilized by ancient Chinese for at least 6800 years.In this study,we evaluate the current known resource diversity of Chinese macrofungi.A total of 1662 taxa are summarized,and all species names and their authorities have been checked and corrected according to authentic mycological databases.Among the 1662 taxa,1020,692,and 480 are considered to be edible,medicinal and poisonous mushrooms,respectively.A few of edible macrofungi in China are commonly used for commercial production.All known medicinal functions are labeled for medicinal species.The most common medicinal functions possessed by Chinese macrofungi are antitumor or anticancer,followed by antioxidant and antimicrobial.A total of 277 Chinese macrofungi are edible simultaneously with certain medicinal functions and without known toxicity.These species could be treated as“Gold Mushrooms”.Contrarily,193 edible and/or medicinal species are also recognized as poisonous mushrooms.To avoid poisoning caused by these species,ingestion either in a proper way or in small amounts is important.However,the mycotoxins metabolized by these poisonous species could be a huge wealth of natural products yet to be explored.How to utilize these Chinese macrofungal resources is a critical to benefit humans worldwide. 展开更多
关键词 Economic fungi Edible mushroom Fungal toxicity Medicinal function NOMENCLATURE
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