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   10662篇
  免费   295篇
各国政治   420篇
工人农民   382篇
世界政治   716篇
外交国际关系   292篇
法律   6748篇
中国政治   69篇
政治理论   2240篇
综合类   90篇
  2020年   105篇
  2019年   157篇
  2018年   192篇
  2017年   221篇
  2016年   216篇
  2015年   162篇
  2014年   187篇
  2013年   951篇
  2012年   220篇
  2011年   269篇
  2010年   213篇
  2009年   271篇
  2008年   270篇
  2007年   271篇
  2006年   263篇
  2005年   241篇
  2004年   239篇
  2003年   244篇
  2002年   238篇
  2001年   424篇
  2000年   367篇
  1999年   297篇
  1998年   162篇
  1997年   125篇
  1996年   138篇
  1995年   133篇
  1994年   137篇
  1993年   137篇
  1992年   234篇
  1991年   252篇
  1990年   242篇
  1989年   249篇
  1988年   227篇
  1987年   224篇
  1986年   263篇
  1985年   257篇
  1984年   230篇
  1983年   214篇
  1982年   153篇
  1981年   127篇
  1980年   114篇
  1979年   151篇
  1978年   86篇
  1977年   111篇
  1976年   95篇
  1975年   74篇
  1974年   90篇
  1973年   84篇
  1972年   78篇
  1971年   69篇
排序方式: 共有10000条查询结果,搜索用时 421 毫秒
91.
92.
Quadratic pieces of fleece measuring 16 mm2 were soaked with 10 different blood-samples in the dilution steps of 1:1, 1:10, 1:100, 1:1000, respectively, and were tested in blood group typing and identification tests of forensic serology. The above spezified dilutions correspond with 5 microliters, 0.5 microliter, 0.05 microliter and 0.005 microliter of blood, respectively. The detection limit of the microspectrometric test for blood was the dilution 1:10, of the porphyrine test a dilution above 1:100, whereas the preliminary test for blood (peroxidase) succeeded always up to a dilution of 1:1000 and the species determination by the radial immunodiffusion test in agar gels succeeded in most cases op to a dilution of 1:1000. The detection limit of the anti-human globulin inhibition test was between the dilution steps 1:10 and 1:100 when non-titrated and undiluted anti-human globulin serum was used. Gc- and ABO-grouping were possible up to a dilution of 1:100 and were thus the most sensitive grouping systems. Phenotyping of the enzyme-systems and the Gm/Km-system usually required stains with considerably higher blood concentrations i.e. stains of undiluted blood.  相似文献   
93.
94.
In 1990, the state of California passed the pioneering mandate on zero emission vehicles (ZEV). This technology‐forcing regulation is aimed at improvement of air quality and protection of public health from the adverse effects of air pollutants from automobiles. Facing severe opposition from the auto industry, the mandate has been revised a number of times, most recently in 2003, whereby the requirement for ZEVs have been made to align with the pace of technology development. Review of strategies used in implementation of the mandate has revealed greater emphasis on the economic incentives for rather than on environmental merits of ZEVs. Using prospect theory as the framework for analysis, the reasons have been explored. The findings of the study help us to understand how decisions are made with respect with to deviations from a mental anchor point and through the process of evaluation of losses and gains.  相似文献   
95.
96.
97.
This report assesses the effects on peripheral oxygen saturation and heart rate that positional restraint induces when a person is prone, handcuffed, and "hog-tied." Peripheral oxygen saturation and heart rate were monitored at rest, during exercise, and during recovery from exercise for 10 adult subjects. The effects of positional restraint produced a mean recovery time that was significantly prolonged. Consequently, the physiological effects produced by positional restraint should be recognized in deaths where such measures are used.  相似文献   
98.
99.
Easterbrook G  Barry J  Thomas R  Clift E  Wingert  Hager M  Cohn B 《Newsweek》1992,120(22):30, 32-34, 36
Lobbyists, entrenched forces in congress and self-interested friends will try to stymie Clinton's efforts. A look at four key arenas of combat.  相似文献   
100.
Thomas R 《Newsweek》1992,120(26):32
  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