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   25477篇
  免费   1255篇
各国政治   950篇
工人农民   1758篇
世界政治   1339篇
外交国际关系   843篇
法律   16767篇
中国共产党   2篇
中国政治   111篇
政治理论   4866篇
综合类   96篇
  2023年   80篇
  2021年   92篇
  2020年   444篇
  2019年   464篇
  2018年   1766篇
  2017年   1722篇
  2016年   1613篇
  2015年   574篇
  2014年   562篇
  2013年   1940篇
  2012年   664篇
  2011年   1365篇
  2010年   1489篇
  2009年   1108篇
  2008年   1204篇
  2007年   1158篇
  2006年   541篇
  2005年   509篇
  2004年   611篇
  2003年   498篇
  2002年   449篇
  2001年   682篇
  2000年   613篇
  1999年   487篇
  1998年   255篇
  1997年   188篇
  1996年   215篇
  1995年   215篇
  1994年   192篇
  1993年   186篇
  1992年   303篇
  1991年   317篇
  1990年   299篇
  1989年   278篇
  1988年   307篇
  1987年   265篇
  1986年   321篇
  1985年   319篇
  1984年   258篇
  1983年   235篇
  1982年   184篇
  1981年   157篇
  1980年   146篇
  1979年   224篇
  1978年   122篇
  1977年   99篇
  1975年   96篇
  1974年   125篇
  1973年   79篇
  1972年   78篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
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   
92.
93.
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   
94.
95.
96.
97.
This paper explores the capacity of alternative theoretical perspectives to explain the self-reported criminality of black and white young adult females. When criminal involvement is regressed on the theory operation-alizations separately by race, a key difference emerges: For white women, significant effects are clustered in the social-psychological theory groups (bonding, attitudes, and maturation), but for the black women the social-psychological variables have only scattered and inconsistent eflects. Instead, for black women structural indicators emerge as the important predictors of criminal involvement.  相似文献   
98.
99.
Comparison of a suspected biter's dental arches with the patterned injury of a bite mark is especially difficult when the bite occurs in an anatomic location with a small radius of curvature or with complex or compound curves. The authors present two case reports in which human skin was used as a template for the reproduction of a bite. In one case the victim's skin was used; in the other, the skin of a anatomically similar person was used. The use of inked dental casts, photography, and transparent overlays significantly reduced the errors common to analysis of bite marks in these highly curved areas.  相似文献   
100.
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