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   67669篇
  免费   3278篇
各国政治   4460篇
工人农民   2835篇
世界政治   5960篇
外交国际关系   3791篇
法律   31620篇
中国共产党   9篇
中国政治   741篇
政治理论   20589篇
综合类   942篇
  2021年   405篇
  2020年   1159篇
  2019年   1515篇
  2018年   1643篇
  2017年   1950篇
  2016年   2148篇
  2015年   1816篇
  2014年   2099篇
  2013年   10487篇
  2012年   1571篇
  2011年   1676篇
  2010年   1804篇
  2009年   2039篇
  2008年   1708篇
  2007年   1683篇
  2006年   1878篇
  2005年   1772篇
  2004年   1660篇
  2003年   1468篇
  2002年   1514篇
  2001年   1533篇
  2000年   1344篇
  1999年   1209篇
  1998年   1084篇
  1997年   968篇
  1996年   944篇
  1995年   903篇
  1994年   916篇
  1993年   926篇
  1992年   935篇
  1991年   972篇
  1990年   919篇
  1989年   969篇
  1988年   949篇
  1987年   979篇
  1986年   946篇
  1985年   1019篇
  1984年   932篇
  1983年   982篇
  1982年   915篇
  1981年   852篇
  1980年   659篇
  1979年   683篇
  1978年   595篇
  1977年   535篇
  1976年   487篇
  1975年   408篇
  1974年   413篇
  1973年   426篇
  1972年   361篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
241.
A simple and sensitive method is described for quantitative analysis of chlorpromazine in blood, serum, urine and tissue homogenate. The chlorpromazine cation radical produced by adding perchloric acid and 2,3-dichloro-5,6-dicyano-p-benzoquinone to the sample can be detected by the ESR method at room temperature. The sensitivity limit is 10 ng, that is, 20 μl of the solution containing 0.5 μg chlorpromazine/ml. The time needed for the measurement is within 10 min. The chlorpromazine radical thus produced is very stable; for example, 95% of the radical was observed after 24 h. The advantage of this method is discussed by comparing with the ordinary spectrophotometry which requires the purification of the sample.  相似文献   
242.
本文是2006年5月25日在香港大学召开的"中非人力资源开发与合作"学术研讨会的系列论文之一。作者基于贫困的持续性与其各构成要素的相互关联性这一机理,运用比较研究方法,测度和评析尼日利亚与中国的减贫政策及其实施效应,反映了国际学术界对减贫问题的研究动态。诚然,本文仅代表作者的观点。  相似文献   
243.
顶空固相微萃取气相色谱法快速检测尿液中氯胺酮   总被引:1,自引:1,他引:0  
目的建立快速检测吸毒人员尿液中氯胺酮的顶空固相微萃取(HS/SPME)-GC/NPD的方法。方法样品瓶中加入尿液、氢氧化钠溶液、氯化钠,在95℃下加热搅拌,用聚二甲基硅氧烷SPME萃取头(100μm)顶空萃取20min,气相色谱氮磷检测器检测,外标法定量。结果尿液中氯胺酮浓度在0.2~20.0μg/ml范围内呈现线性关系(r2=0.9965),尿液添加1.0μg氯胺酮,平均回收率102.6%,RSD=3.39%(n=7),检测限1.13ng/ml(S/N=3)。结论建立的方法简单、快速、灵敏、准确,十分适合尿液等生物检材中氯胺酮的快速定性定量分析。  相似文献   
244.
245.
246.
247.
The main aim of this paper is to advance knowledge and (especially) theories about developmental and life‐course criminology (DLC). First, I review the widely accepted DLC findings that all DLC theories have been designed to explain. Second, I review more contentious and unresolved empirical DLC issues that might present challenges to DLC theories. Third, I describe my own DLC theory and specify how it addresses key empirical and theoretical questions. Fourth, I summarize five important DLC theories, by Catalano and Hawkins, Sampson and Laub, Moffitt, LeBlanc, and Thornberry and Krohn. Fifth, I identify differences in assumptions and predictions between my theory and the other five theories. Finally, I recommend a detailed comparison of the key features of all DLC theories, of their answers to key empirical and theoretical questions, and of their predictions regarding key unresolved empirical DLC issues.  相似文献   
248.
Research has indicated that school factors such as communal school organization and student bonding are predictive of school disorder, with greater communal organization and greater student bonding leading to less delinquency and victimization. Data from a nationally representative sample of 254 public, nonalternative, secondary schools were used to examine structural equation models representing hypothesized relationships among communal school organization, student bonding, and school disorder. The hypothesis that communally organized schools would have less disorder held true for teacher victimization and student delinquency, but not for student victimization. In addition, the hypothesis that the relationship between communal school organization and school disorder would be mediated by student bonding was supported for student delinquency, but not for teacher victimization.  相似文献   
249.
“Discretion” holds an unrivaled position at the core of the notional inventory employed in the study of criminal justice generally and policing particularly. Efforts to systematically define the term have been irregular and its status in the empirical literature is an ambiguous one. While spoken of as a quantitative aspect of the policing which influences behavior, measurement is rarely addressed. After sketching problems in present formulations, discretion is recast in terms of perceived job autonomy and an outline of two general constructs is contributed in hopes of renewing consideration of the potential relevance of the concept for police theory and research.  相似文献   
250.
To demonstrate that norms have independent causal power, constructivists de-emphasise material factors related to state interests and highlight social factors. Similarly, they conceptualise international organisations as autonomous from state influence, and focus on cases featuring non-state actors that stimulate a “tipping point” of norm diffusion among states in advance of state sponsorship. By contrast, this article utilises an historical materialist approach that admits both social and material data to examine the contrasting case of population control. It finds that US corporate foundations, eugenist demographers, feminist birth control activists and related NGOs conceptualised and promoted population control in the United States, at the United Nations, and across developing countries. However, the tipping point of norm diffusion occurred only after the United States publicly advocated population control. Indeed, material and social factors were inextricably bound together.  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