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   21165篇
  免费   1309篇
各国政治   907篇
工人农民   978篇
世界政治   1425篇
外交国际关系   649篇
法律   14407篇
中国共产党   3篇
中国政治   130篇
政治理论   3856篇
综合类   119篇
  2021年   100篇
  2020年   452篇
  2019年   487篇
  2018年   619篇
  2017年   660篇
  2016年   731篇
  2015年   567篇
  2014年   603篇
  2013年   2207篇
  2012年   588篇
  2011年   599篇
  2010年   607篇
  2009年   615篇
  2008年   610篇
  2007年   601篇
  2006年   619篇
  2005年   533篇
  2004年   536篇
  2003年   453篇
  2002年   488篇
  2001年   815篇
  2000年   723篇
  1999年   577篇
  1998年   296篇
  1997年   218篇
  1996年   229篇
  1995年   239篇
  1994年   214篇
  1993年   221篇
  1992年   373篇
  1991年   379篇
  1990年   375篇
  1989年   347篇
  1988年   365篇
  1987年   332篇
  1986年   411篇
  1985年   413篇
  1984年   312篇
  1983年   300篇
  1982年   222篇
  1981年   195篇
  1980年   186篇
  1979年   253篇
  1978年   164篇
  1977年   123篇
  1976年   107篇
  1975年   135篇
  1974年   173篇
  1973年   127篇
  1972年   116篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
Toxicologic findings in the USS Iowa disaster.   总被引:5,自引:0,他引:5  
The toxicologic results from the 47 victims of the explosion on the USS Iowa are presented. Good correlation between carboxyhemoglobin saturations and cause of death was found. There were no correlations between blood cyanide concentrations and causes of death. Volatile analysis suggested postmortem ethanol production rather than antemortem ethanol ingestion. No drugs except nicotine were detected in any of the victims.  相似文献   
122.
123.
124.
In this study, a new method was developed for the impurity profiling of illicit MDMA tablets. The extraction efficiency, linearity, repeatability and reproducibility of the method were evaluated. Eighty two MDMA tablets coming from presumed unrelated large seizures in 2004 (n >500 tablets) were analyzed by gas chromatography mass spectrometry (GC-MS) in order to assess the discrimination power of the method. The latter was found to be practical, robust, relatively easy to perform, highly discriminative and yielding good chromatography. In addition, some new impurities were detected and identified. Their chemical structures and mass spectra are reported.  相似文献   
125.
The legislator, in the German Federal Republic, has opted for a specific legal solution in relation to the protection of the embryo. Carola Müller, in this article, describes this regulation as well as the reasons that have led to its adoption. The article finishes with an exposition of the existing social discussion in German society and the effect that the law has had.  相似文献   
126.
More than a decade after NAFTA (North American Free Trade Agreement) entered into force, the environmental effects of agricultural trade liberalization in Mexico are still controversial, emerging, and not fully understood. This paper contributes to the literature that aims to explore trends in input use in the agricultural sector in Mexico during the post-NAFTA period among both commercial/industrial and traditional/rainfed farmers, and examines the influence of the national and multilateral institutional framework on these outcomes. We decompose the post-NAFTA agricultural production data into scale, technique and composition effects to estimate the impact that trade liberalization has had on the use of fertilizer and land use, two key agricultural inputs for which reliable aggregate data is available. We conclude that among commercial farmers patterns of crop type specialization and significant technological improvements have led to some declines in fertilizer use but they have been offset by growth in fertilizer use associated with growing agricultural output. Among traditional farmers increased output and specialization in land-intensive grain crops are contributing to an increase in land under cultivation and technological improvements show the potential, but not yet not the strength, to counteract these effects. We analyse the environmental institutional framework and rural development plans, observing that institutional weaknesses have, in several instances, reduced the environmental benefit of technique and composition effects. We conclude with recommendations about how the Mexican agricultural sector might reap the environmental benefits of international agricultural trade.  相似文献   
127.
128.
This article reports the results of a study of the antecedents of long-term success in community mediation. Seventy-three mediation sessions were recorded and content analyzed. The participants were interviewed at two points: immediately after mediation and 4 to 8 months later. No relationship was found between the quality of the agreements—i.e., the extent to which they solved immediate problems- and long-term success as measured by compliance, improved relations between the parties, and the absence of new problems. On the other hand, joint problem solving by the disputants was related to complainant perceptions of improved relations with the other party. Also respondent perceptions that the mediation had been fair and that all the problems had come out were related to all aspects of long-term success in the eyes of the complainant. The latter results support a procedural justice analysis of mediation and underline the importance of mediator attention to the respondent.  相似文献   
129.
130.
Criminal justice policies may be enacted, but the actual implementation of those policies depends upon those working on the frontline. Policies that affect how cases are processed in the courtroom can be thwarted by the efforts of courtroom workgroup members. The present study analyzed how courtroom workgroups adjusted to a new juvenile justice policy. Qualitative interviews demonstrated that while there was widespread agreement on the basic tenets of the reform, perceptions of the reform varied by confidence in workgroup membership. Further, the reform inherently increased the workload for some and decreased the workload for others. Those whose workload increased discussed subverting the reform effort in order to continue with business as usual. These findings demonstrated that effective policies must consider the needs of workgroups as adaptation of policies in actual practice depend upon workgroup members' support.  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