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   20492篇
  免费   1272篇
各国政治   903篇
工人农民   913篇
世界政治   1448篇
外交国际关系   778篇
法律   13421篇
中国共产党   4篇
中国政治   139篇
政治理论   4028篇
综合类   130篇
  2023年   89篇
  2021年   113篇
  2020年   466篇
  2019年   500篇
  2018年   650篇
  2017年   672篇
  2016年   754篇
  2015年   566篇
  2014年   614篇
  2013年   2347篇
  2012年   545篇
  2011年   594篇
  2010年   615篇
  2009年   643篇
  2008年   599篇
  2007年   579篇
  2006年   610篇
  2005年   536篇
  2004年   525篇
  2003年   434篇
  2002年   504篇
  2001年   742篇
  2000年   675篇
  1999年   536篇
  1998年   293篇
  1997年   220篇
  1996年   224篇
  1995年   233篇
  1994年   219篇
  1993年   215篇
  1992年   339篇
  1991年   355篇
  1990年   326篇
  1989年   316篇
  1988年   328篇
  1987年   296篇
  1986年   348篇
  1985年   352篇
  1984年   273篇
  1983年   262篇
  1982年   212篇
  1981年   198篇
  1980年   176篇
  1979年   252篇
  1978年   146篇
  1977年   106篇
  1976年   104篇
  1975年   109篇
  1974年   139篇
  1973年   94篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
111.
112.
113.
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   
114.
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   
115.
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   
116.
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   
117.
118.
The story of Al Capone's rise and fall as a Chicago gangster has always depended upon selective dissemination of federal agency records, particularly records of the Internal Revenue Service. Capone history, therefore, is state-sanctioned history. The IRS view of the Capone organization, and of the tax evasion conviction, cannot be easily challenged without access to the corpus of the IRS records. Unfortunately, these records remain sealed from public access, despite the fact that selective releases were made prior to 1977 to journalists, popular authors, film producers and historians. Continued secrecy over the Capone records perpetuates a state-sanctioned criminology of organized crime. Calder v. Internal Revenue Service 1 attempted without success to unlock the corpus of IRS-Capone records to investigate the state-sanctioned view.  相似文献   
119.
120.
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