首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   35946篇
  免费   1718篇
各国政治   1682篇
工人农民   1484篇
世界政治   2942篇
外交国际关系   1447篇
法律   21927篇
中国共产党   3篇
中国政治   212篇
政治理论   7672篇
综合类   295篇
  2021年   193篇
  2020年   643篇
  2019年   732篇
  2018年   981篇
  2017年   1039篇
  2016年   1179篇
  2015年   814篇
  2014年   927篇
  2013年   4034篇
  2012年   949篇
  2011年   980篇
  2010年   920篇
  2009年   963篇
  2008年   1022篇
  2007年   1064篇
  2006年   1053篇
  2005年   906篇
  2004年   945篇
  2003年   835篇
  2002年   853篇
  2001年   1266篇
  2000年   1169篇
  1999年   973篇
  1998年   554篇
  1997年   456篇
  1996年   430篇
  1995年   426篇
  1994年   454篇
  1993年   426篇
  1992年   621篇
  1991年   650篇
  1990年   615篇
  1989年   607篇
  1988年   602篇
  1987年   580篇
  1986年   628篇
  1985年   611篇
  1984年   526篇
  1983年   497篇
  1982年   419篇
  1981年   390篇
  1980年   320篇
  1979年   443篇
  1978年   277篇
  1977年   231篇
  1976年   205篇
  1975年   218篇
  1974年   260篇
  1973年   188篇
  1972年   187篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
171.
172.
An improved method has been developed for the reliable classification of different C1R genetic variant forms from human serum or plasma. The method combines the use of neuraminidase-digested samples followed by monodimensional isoelectric focusing in the pH range 5 to 8 followed by immunoblotting. The method yields a simple pattern, with one major band in homozygote and two major bands in heterozygote cases.  相似文献   
173.
Dilutions of 100 serum samples of various GM phenotypes were dotted onto a nitrocellulose membrane. The serum dot-blots were detected with peroxidase-labeled anti-G3M T monoclonal antibody (anti-G3M T MAb). Up to a 1 : 256 dilution could be G3M T-typed correctly. By use of anti-G3M T MAb and peroxidase-labeled anti-mouse IgG or the biotin-avidin system instead of use of labeled anti-G3M T MAb, up to a 1 : 512 or 1 : 1024, respectively, dilution was typable. As with previous work with G3M G MAb, the dot immunobinding (DIB) method for G3M T typing was found very simple and practical.  相似文献   
174.
The impact of research information depends on its ability to change beliefs or policy assumptions within the relevant audiences. As a hybrid of American and British systems, Canada's chosen decision-making structure for policy-making and its legislative framework for health insurance make these audiences unclear and not readily accessible. This factor and historical characteristics of the research community which made them only partially responsive to the values of decisionmakers provide an explanation for the limited past use of research information in Canadian health policy. More recently, improved responsiveness by researchers and an emerging definition of the audiences by legislative policymakers are bringing about a gradual increase in the potential impact of research at the levels of administrative and clinical policy. Because of continuing decision-making constraints on legislative policy, however, impact at this level is predicted to remain diffuse, with only cautious acceptance of the changes in beliefs implied by research.  相似文献   
175.
A technique was developed for Gm/Km typing of bloodstains and sera in U-bottom microtiter plates. Gm/Km typing of sweat and urine samples was also attempted with limited success.  相似文献   
176.
177.
178.
179.
HIV infection is now perceived as the end stage of a chronic disease that is spreading most rapidly among blacks and Hispanics. The politics of the HIV epidemic in the 1980s were dominated by four interacting factors: fear and fascination; who had the disease and to whom it seemed to be spreading; the endemic problems of United States social policy; and the impact on policy of advances in scientific knowledge. This paper analyzes the political history of each of these factors and describes the dominant policies of the federal government and the states regarding HIV in the areas of surveillance, prevention, research, and financing. Four uncertainties will have a profound influence on the future politics of the HIV epidemic: how the states and the federal government will address the general problems of paying for the care of people with chronic diseases and providing access to care for the uninsured and the underinsured; the number and distribution of the sexual behaviors that transmit infection with HIV and the effectiveness of policies to persuade people to modify these behaviors; precisely who uses addictive drugs and the effectiveness of measures to change their behavior; and the natural history of the virus.  相似文献   
180.
China's experiments with democracy in this century were few in number, short in duration, and limited in their democratic characteristics. Democratic institutions malfunctioned in numerous ways. Nine sets of causes for the failure of Chinese democracy can be suggested: ideology, internal and external war, military intervention, Chinese political culture, underdevelopment, a peasant mass, flaws in the design of Chinese constitutions, moral failures by democratic politicians, or the lack of transactional benefits for military‐based elites in the process of democratic transition. Each of these factors is reviewed critically with an eye to its possible lessons.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号