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   17342篇
  免费   501篇
各国政治   720篇
工人农民   683篇
世界政治   1445篇
外交国际关系   603篇
法律   10365篇
中国共产党   2篇
中国政治   79篇
政治理论   3769篇
综合类   177篇
  2020年   210篇
  2019年   250篇
  2018年   329篇
  2017年   389篇
  2016年   419篇
  2015年   289篇
  2014年   335篇
  2013年   1706篇
  2012年   405篇
  2011年   437篇
  2010年   347篇
  2009年   388篇
  2008年   462篇
  2007年   471篇
  2006年   449篇
  2005年   399篇
  2004年   410篇
  2003年   427篇
  2002年   384篇
  2001年   682篇
  2000年   620篇
  1999年   509篇
  1998年   298篇
  1997年   247篇
  1996年   206篇
  1995年   214篇
  1994年   248篇
  1993年   224篇
  1992年   339篇
  1991年   373篇
  1990年   330篇
  1989年   348篇
  1988年   322篇
  1987年   337篇
  1986年   341篇
  1985年   335篇
  1984年   290篇
  1983年   323篇
  1982年   258篇
  1981年   239篇
  1980年   186篇
  1979年   251篇
  1978年   170篇
  1977年   151篇
  1976年   133篇
  1975年   121篇
  1974年   137篇
  1973年   121篇
  1972年   117篇
  1971年   94篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
131.
132.
133.
134.
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   
135.
136.
The end of the twentieth century was marked by a sea change in global governance in the realm of intellectual property rights (IPRs). Whereas countries historically retained substantial autonomy with regard to what they defined as intellectual "property" and the rights granted to the owners of intellectual property, the 1990s witnessed the establishment of new global obligations regarding national practices. This paper focuses on the case of software "piracy" to assess the mechanisms by which the new global obligations for the treatment of IPRs are transmitted from the international to the national levels. We first consider a set of national-level factors that many scholars have shown to be important determinants of IPR policy. We then supplement the standard emphasis on domestic factors with an analysis of new transnational factors: countries' multilateral obligations under the World Trade Organization's (WTO) Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) and bilateral pressures from the United States to increase the protection of IPRs. Population-averaged panel data models are used to assess the effects of these national and transnational determinants on levels of software piracy in 80 countries from 1994 to 2002. Our results indicate that membership in the WTO and bilateral pressures from the United States—particularly pressures that offer reciprocal concessions—lead to substantial increases in levels of protection in rich and poor countries. There is, in short, a new international political economy of intellectual property.  相似文献   
137.
138.
Eight homicidal youths were assessed for language disorders and psychiatric diagnoses using a battery of standardized language tests and the Diagnostic Interview for Children and Adolescents. Both language disorders and Diagnostic and Statistical Manual III-R psychiatric diagnoses were present in all subjects.  相似文献   
139.
140.
Although physical punishment has been studied for decades, there are gaps in the literature regarding frequently used form, context, and cross cultural differences. A comparison was made using 227 college students in the United States and Japan, who were presented with four scenarios and surveyed regarding attitudes toward physical punishment, perceptions of appropriate discipline methods, and past experience with physical punishment. Japanese and U.S. respondents reported similar personal experience with physical punishment (Japanese 86%, U.S. 91%). However, U.S. respondents reported a higher likelihood of being hit with an object than did Japanese respondents. For U.S. respondents, the bottom and the hand were the top two sites on the body used for physical punishment, whereas the head and the face were the top two places for the Japanese sample. Unlike U.S. respondents, type of child misbehavior was found to have an impact on Japanese respondents’ views on the appropriate discipline method.  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