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   15393篇
  免费   224篇
各国政治   440篇
工人农民   1278篇
世界政治   657篇
外交国际关系   507篇
法律   9564篇
中国政治   58篇
政治理论   3076篇
综合类   37篇
  2020年   96篇
  2019年   118篇
  2018年   1397篇
  2017年   1334篇
  2016年   1171篇
  2015年   170篇
  2014年   180篇
  2013年   686篇
  2012年   345篇
  2011年   1089篇
  2010年   1144篇
  2009年   732篇
  2008年   922篇
  2007年   902篇
  2006年   240篇
  2005年   239篇
  2004年   358篇
  2003年   349篇
  2002年   194篇
  2001年   318篇
  2000年   298篇
  1999年   221篇
  1998年   94篇
  1997年   84篇
  1996年   97篇
  1995年   96篇
  1994年   98篇
  1993年   63篇
  1992年   142篇
  1991年   153篇
  1990年   140篇
  1989年   158篇
  1988年   135篇
  1987年   152篇
  1986年   135篇
  1985年   153篇
  1984年   129篇
  1983年   146篇
  1982年   98篇
  1981年   93篇
  1980年   69篇
  1979年   105篇
  1978年   83篇
  1977年   77篇
  1976年   58篇
  1975年   48篇
  1974年   57篇
  1973年   59篇
  1971年   50篇
  1970年   46篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
The fingernail ridge patterns of a pair of identical twins were compared to each other, their parents, and an unrelated subject. The patterns of the twins' nails showed regions of strong similarity but were distinguishable from one another. Fewer similarities were found when comparing the nails to those of the parents and the unrelated control. The twins were shown to be monozygotic by means of DNA profiling. This therefore represents the first demonstration of unique fingernail ridge patterns in subjects shown conclusively to be identical twins. When the fingernail ridge patterns were examined with a scanning electron microscope, the backscattered electron (BEI) images were found to have superior contrast when compared to the secondary electron (SEI) images.  相似文献   
122.
123.
The European Parliament has generally been deeply distrustful of the comitology system, primarily on the grounds that it allows the national administrations to undermine its supervisory role in the area of implementing legislation. Parliament has therefore sought to use the political, budgetary and jurisdictional means at its disposal to counteract the spread of comitology, or at least to promote the less intrusive forms of committee procedure. These initiatives have not, for the most part, been wholly successful; neither the interinstitutional agreements nor Parliament's arguments before the Court of Justice have produced the results it had hoped for. Parliament has been able, however, to use its Maastricht powers to influence the choice of committee procedure included in legislation adopted under codecision, and its budgetary tactics have forced the Commission to rationalise somewhat the annual expenditure on committees of all kinds and to bring a modicum of transparency into their operation. The imminence of the intergovernmental conference led to a suspension of hostilities towards the end of 1996.  相似文献   
124.
The analysis of naphthenic acid revealed that they may be used for tin detection in the cadaveric material due to their high complex-forming ability. Method of extraction-atomic absorption tin determination in human organs was developed on the basis of naphthenic acid use. Modified method which differs from the common one by higher sensitivity and selectivity is presented.  相似文献   
125.
126.
127.
128.
This study investigated the influence of an authority figure on eyewitness identification. Participants watched a staged crime and then were administered a photo lineup by either an authority (policeman) or non-authority figure (civilian). Participants in the authority condition were more likely to choose a lineup member than those in the non-authority condition. There was no effect of authority, however, on the accuracy of the identification decisions. The lack of a deleterious effect suggests that the presence of a police officer during identification procedures does not create an unduly suggestive situation or have undesirable effects on eyewitness identification decisions. Although witnesses' choosing behaviors did not increase the rate of identification errors, the effect of the administrator's authority on choosing was reduced when unbiased instructions (vs. biased instructions) were presented to the witnesses. Thus, support was found for the use of neutral instructions during eyewitness identification procedures.  相似文献   
129.
130.
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