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   1533篇
  免费   79篇
各国政治   84篇
工人农民   65篇
世界政治   109篇
外交国际关系   145篇
法律   780篇
中国政治   11篇
政治理论   408篇
综合类   10篇
  2023年   19篇
  2022年   25篇
  2021年   22篇
  2020年   41篇
  2019年   63篇
  2018年   59篇
  2017年   73篇
  2016年   87篇
  2015年   41篇
  2014年   73篇
  2013年   212篇
  2012年   71篇
  2011年   51篇
  2010年   45篇
  2009年   50篇
  2008年   56篇
  2007年   71篇
  2006年   51篇
  2005年   65篇
  2004年   51篇
  2003年   50篇
  2002年   47篇
  2001年   30篇
  2000年   21篇
  1999年   26篇
  1998年   16篇
  1997年   14篇
  1996年   8篇
  1995年   18篇
  1994年   11篇
  1993年   5篇
  1992年   20篇
  1991年   7篇
  1990年   11篇
  1989年   11篇
  1988年   8篇
  1987年   10篇
  1986年   11篇
  1985年   7篇
  1984年   4篇
  1983年   8篇
  1982年   5篇
  1981年   3篇
  1980年   6篇
  1975年   4篇
  1973年   3篇
  1970年   2篇
  1969年   3篇
  1966年   3篇
  1962年   2篇
排序方式: 共有1612条查询结果,搜索用时 15 毫秒
11.
12.
The impact of high temperatures (24 to 39 degrees C) and low to moderately high humidities (20 to 70%) on the applicability of TLC systems for drug identification was studied during a 6 month climatologic cycle in Burkina Faso (West Africa). In general, the Rf values as observed on the plates were found to be substantially affected as compared with values obtained at temperate climates. Some TLC systems were more affected than others and the largest deviations of up to 30 Rf units were at low humidities. Tropical conditions also had a negative effect on the reproducibility of Rf values. However, when an Rf-correction procedure was applied, using reference mixtures of known drugs on each plate, accuracy as well as reproducibility of the resulting Rfc values were drastically improved and data thus corrected were found to be compatible with existing TLC data bases developed under moderate climatological conditions. The impact of high to extremely high humidities (70 to 100%) remains to be investigated.  相似文献   
13.
测定了痢疾杆菌福氏 2a 30 1株与喹喏酮类药物耐药性相关的 gyrA基因和 parC基因的序列 ,并对其环丙沙星耐药诱变株的 gyrA和 parC基因喹喏酮类药物耐药性决定区 (QRDR)序列进行了测定分析。结果表明 ,痢疾杆菌福氏 2a 30 1株 gyrA和 parC基因分别为 2 6 2 5bp和2 2 5 6bp ,环丙沙星诱导的耐药菌 gyrA基因QRDR(2 4 5bp)发生氨基酸残基 6 9 Ala→Val和 87 Tyr→Asp改变 ,parC基因QRDR(2 37b)发生氨基酸残基 79 Ala→Asp、84 Ala→Glu和 85 Pro→Ala改变。这一研究结果对认识痢疾杆菌喹喏酮类药物耐药性的分子机理具有重要意义  相似文献   
14.
15.
Studies of restorative justice programs continue to provide a review of restorative justice practice and impact. While this body of research is growing, many questions remain regarding the impact of restorative justice in reducing crime. By relying on individual and community-level data, the present study examined how offense type and poverty level influenced program completion and recidivism among juveniles in a restorative justice program. This study also examined the relationship between program completion and recidivism. Findings revealed that status offenders in the restorative justice program were more likely to complete the program and less likely to recidivate than status offenders in the comparison group. In addition, property offenders in the restorative justice program were less likely to recidivate than property offenders in the comparison group. Poverty level at the community-level had a significant influence in both program completion and recidivism.  相似文献   
16.
Drug trade is widely seen as a phenomenon rather new to the Netherlands. However, at the beginning of the 20th century the Dutch pharmaceutical industries were already extensively involved in the production of both opiates and cocaine, and they went on exporting large quantities of these drugs after the Opium Act (1919) took force. Until the 1960s, arrests were not at all common, and these largely affected minority groups like Chinese opium smokers and black marijuana users. Since then, drug control efforts have increased by leaps and bounds. At first, cannabis was the main target; then the focus turned to heroin, and that was later joined by cocaine. This paper traces the history of the drug trade and drug control in the Netherlands, with emphasis on their development in Amsterdam. The conclusion is reached that, in spite of drastic changes in both drug trade and drug control, certain ideologies, constructs and strategies have remained remarkably stable.  相似文献   
17.
Goran Therborn, European Modernity and Beyond: The Trajectory of European Societies, (Sage, London 1995). 403pp. ISBN 8039 8934 2.

John McGany and Brendan O'Leary, Explaining Northern Ireland, (Blackwell, Oxford 1995). 535pp. ISBN 0–631–18349–3.  相似文献   

18.
19.
The growing literature about mixed electoral systems has addressed their effect on party systems, voting behavior, campaign strategies, legislative roll-call voting, and other issues in a handful of countries. But, the effect of mixed systems has not been fully evaluated cross-nationally or longitudinally. Using data from the World Bank’s Database of Political Institutions, we address this gap in the literature by investigating two related questions. First, do mixed electoral rules produce different election outcomes than other election rules? Second, are these results attenuated by the definitions of mixed systems that scholars employ? We find that mixed systems generate outcomes that are distinct from other electoral systems and that these findings are generally robust across different definitions.  相似文献   
20.
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