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   10148篇
  免费   345篇
各国政治   672篇
工人农民   408篇
世界政治   793篇
外交国际关系   425篇
法律   5603篇
中国共产党   2篇
中国政治   141篇
政治理论   2312篇
综合类   137篇
  2020年   136篇
  2019年   167篇
  2018年   212篇
  2017年   245篇
  2016年   241篇
  2015年   219篇
  2014年   223篇
  2013年   1220篇
  2012年   263篇
  2011年   343篇
  2010年   256篇
  2009年   282篇
  2008年   274篇
  2007年   262篇
  2006年   264篇
  2005年   227篇
  2004年   261篇
  2003年   275篇
  2002年   195篇
  2001年   389篇
  2000年   358篇
  1999年   308篇
  1998年   162篇
  1997年   116篇
  1996年   128篇
  1995年   120篇
  1994年   124篇
  1993年   126篇
  1992年   176篇
  1991年   181篇
  1990年   163篇
  1989年   160篇
  1988年   169篇
  1987年   178篇
  1986年   185篇
  1985年   158篇
  1984年   164篇
  1983年   170篇
  1982年   114篇
  1981年   82篇
  1980年   95篇
  1979年   107篇
  1978年   96篇
  1977年   76篇
  1976年   75篇
  1975年   63篇
  1974年   57篇
  1973年   56篇
  1971年   55篇
  1969年   57篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
131.
This paper describes some of the spinoff benefits that can result from R&D projects, and categorizes them in terms of the dimensions of market and technical newness. These dimensions are discussed with reference to two types of spinoffs: 1) alternative market applications, when the results of an R&D project are subsequently applied to a market or use that differs from the originally intended application, and 2) second-generation technologies, when the technology that was the subject of an R&D project is significantly altered or enhanced in unanticipated ways through subsequent R&D. Examples from the Department of Energy's Energy-Related Inventions Program are integrated into the results of literature review to illustrate key concepts, including core technologies, degrees of market and technology newness, technology robustness, and the nature of connections linking spinoffs to prior R&D investments. The paper concludes by discussing spinoffs as a managerial strategy.  相似文献   
132.
133.
The median and the competitive equilibrium in one dimension   总被引:1,自引:0,他引:1  
Two alternative models of legislative outcomes are the minimum winning coalition and the competitive equilibrium (Koford, 1982). In a unidimensional setting, the outcome under the former is the median, while the outcome under the latter is the highest net demand location.This paper describes the competitive equilibrium in a unidimensional model, and shows that under some common conditions it coincides with the median, in particular for pure redistributive issues. However, for distributive issues, the two equilibria will differ. Finally, the comparative statics of the two models are examined; while the winning coalition is sensitive only to changes in the location of the median, for distributive issues the competitive equilibrium has the standard economic comparative statics that the outcome adjusts in the direction of the change in preferences.  相似文献   
134.
The “tragedy of the commons” is the familiar problem that open access to a common property resource leads to overexploitation and to zero profits. A commons model is applied to an example of state sponsored private violence, the practice of privateering or licensed piracy. It is predicted that the presence of uncertainty about the value of the prey will reduce the amount of exploitation effort, and that industry profits may be positive due to both uncertainty and heterogeneous exploiters. Using data from England's wars with France and Spain between 1625 and 1630, the model suggests that the commons, represented by enemy merchant shipping, was not overexploited and that privateering profits were positive. The dynamic paths of privateering effort, ships seized, and individual firm profits were, however, consistent with the normal expectation that commons exploitation will peak and fall, as competition drives down returns through entry. “England was never richer than when at war with Spain.” Sir Edward Coke   相似文献   
135.
Vipond  Robert C. 《Publius》1993,23(3):39-56
On 26 October 1992, a majority of Canadians in a majority ofprovinces rejected the Charlottetown Accord in a national referendum.The accord capped the "Canada round" of constitutional negotiationsand attempted to satisfy Quebec, while also addressing otherpan-Canadian issues. The accord was defeated for different reasonsin different parts of the country. In Quebec, the "No" sideargued that the agreement did not meet their demands for greaterjurisdictionalautonomy within the federation. In the rest of Canada, the "No"side was particularly successful in demonstrating that the agreementdeviated from the principle of equality in the treatment ofindividuals and provinces. These critiques, inspired by differentvisions of the federation, lead in different directions. Inlight of these divisions, many commentators have suggested thatintergovernmental elites ought to abandon efforts of wholesaleconstitutional change. However, political developments in Quebecmay force these questions back onto the agenda.  相似文献   
136.
The author reviews current demographic trends in the countries of the European Community in the light of the efforts to abolish frontiers and border controls among member countries. She shows that there has been a general trend toward commonality in many aspects of demographic behavior.  相似文献   
137.
"Constitution of a trade bloc between Mexico, the United States and Canada through the North American Free Trade Agreement (NAFTA) in this decade has called attention to...the role of Mexico's southern border, Central American conflicts and migrations from that era. Relevant adjustments have been made to Mexico's policy in approaching problems regarding its southern neighbors. These changes respond largely to the perception held by larger economic blocs and migration generated by unequal development levels within these regions and countries." (SUMMARY IN ENG)  相似文献   
138.
139.
Measuring School-Related Stressors in Adolescents   总被引:2,自引:0,他引:2  
Some 1620 high school students responded to 68 items that measure adolescent stressors. Thirty-five of the items were based on J. P. Kohn and G. H. Frazer's Academic Stress Scale [1(1986) An Academic Stress Scale: Identification and Rated Importance of Academic Stressors, Psychological Reports, Vol. 59, pp. 415–426] developed in the United States, while the remaining 33 items were developed from P. Strutynski's [(1985) A Survey of Queensland Year 10, 11 and 12 Student Attitudes to Schools and Schooling, State Planning Committee, International Youth Year, Brisbane] lists of the most frequently named problems of 2336 Australian high school students. Confirmatory Factor Analysis was used to test and develop a measurement model developed from an extensive review of previous scales. The High School Stressors Scale emerged from the analytic process and measures nine school-related stressors. For researchers focusing on school-related problems and stressors among adolescents, the HSSS promises to be a very useful instrument. It has sound construct and predictive validity and adequate reliability, as demonstrated by the goodness-of-fit indices the squared multiple correlations.  相似文献   
140.
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