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   31581篇
  免费   1551篇
各国政治   1328篇
工人农民   1349篇
世界政治   2399篇
外交国际关系   1067篇
法律   20235篇
中国共产党   3篇
中国政治   167篇
政治理论   6332篇
综合类   252篇
  2021年   157篇
  2020年   583篇
  2019年   641篇
  2018年   832篇
  2017年   881篇
  2016年   989篇
  2015年   705篇
  2014年   803篇
  2013年   3266篇
  2012年   809篇
  2011年   856篇
  2010年   805篇
  2009年   857篇
  2008年   866篇
  2007年   883篇
  2006年   874篇
  2005年   763篇
  2004年   783篇
  2003年   703篇
  2002年   719篇
  2001年   1177篇
  2000年   1085篇
  1999年   878篇
  1998年   487篇
  1997年   386篇
  1996年   367篇
  1995年   373篇
  1994年   396篇
  1993年   369篇
  1992年   566篇
  1991年   603篇
  1990年   571篇
  1989年   564篇
  1988年   553篇
  1987年   548篇
  1986年   585篇
  1985年   583篇
  1984年   495篇
  1983年   475篇
  1982年   394篇
  1981年   369篇
  1980年   304篇
  1979年   427篇
  1978年   259篇
  1977年   219篇
  1976年   194篇
  1975年   205篇
  1974年   239篇
  1973年   184篇
  1972年   182篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
103.
Bloodstains were made with 200 microliters blood on each of 11 different common substrates to examine the effect of the stain carrier on the amount and quality of DNA recoverable. High-molecular-weight DNA was extracted from all samples after 2 days. The yield of DNA from each sample varied considerably, not only between the different stain carriers but also within a given category. With a DNA yield of up to 10 micrograms, paper, glass, nylon, wood, smooth leather and wool gave the best results, followed by blue denim and wallpaper (up to 6 micrograms), cotton fabric and carpeting (up to 4 micrograms) and suede (up to 2 micrograms). For several stain carriers the DNA-containing solution was contaminated by chemical substances, which in the case of the blue denim, suede, and carpet samples inhibited the digestion of the DNA with restriction enzymes and prevented DNA typing. The different textures of the stain carriers tested and (as for varying yields on the same carrier) the differing degree of loss of DNA during extraction and the physiological variation in the number of leukocytes in human blood are discussed as possible reasons for the wide range of variation in the amounts of DNA it was possible to extract.  相似文献   
104.
105.
106.
107.
On the basis of the uncertainty management model, we argue here that when people are uncertain about an organization's trustworthiness, they may resolve the question how they should react toward the organization by relying on their perceptions of the organization's procedures. As a consequence, we predicted that the reactions of parents whose child was in a day care center would be strongly influenced by their perceptions of the procedures used by the organization that was responsible for their children's day care when the parents would be uncertain about the organization's trustworthiness. However, when parents would be certain that the organization could be trusted they would be less in need of procedural information, yielding less strong effects of perceived procedure on parents' reactions. The findings of a survey study corroborate this line of reasoning. In the discussion it is argued that these findings suggest that people especially rely on their perceptions of procedures when they are uncertain about important aspects of their lives, such as the trustworthiness of organizations that are responsible for their children's day care.  相似文献   
108.
This article discusses relevant literature on the potential benefits of sport, recreation, and leisure, and how these benefits relate to rehabilitation of juveniles. Many professionals involved in juvenile rehabilitation believe sport and recreation are beneficial adjuncts to treatment programming; however, it can be difficult to structure sport and recreation in ways that directly correspond to treatment goals. The purpose of this article is to provide insights for professionals working with juveniles on how sport and recreation programming can be an effective means of helping to achieve rehabilitation goals. Attention is given to approaches, particularly the Teaching Games for Understanding model (Bunker & Thorpe, 1982), which can be used to effectively link recreation and sport to the rehabilitation process.  相似文献   
109.
110.
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