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   207102篇
  免费   8804篇
  国内免费   155篇
  2020年   2822篇
  2019年   3487篇
  2018年   4046篇
  2017年   4390篇
  2016年   4966篇
  2015年   3978篇
  2014年   4838篇
  2013年   23588篇
  2012年   5835篇
  2011年   5373篇
  2010年   4507篇
  2009年   5075篇
  2008年   5304篇
  2007年   4864篇
  2006年   5094篇
  2005年   4909篇
  2004年   4445篇
  2003年   3998篇
  2002年   3802篇
  2001年   5062篇
  2000年   4813篇
  1999年   4192篇
  1998年   3003篇
  1997年   2769篇
  1996年   2683篇
  1995年   2520篇
  1994年   2482篇
  1993年   2437篇
  1992年   3476篇
  1991年   3287篇
  1990年   3154篇
  1989年   2994篇
  1988年   2967篇
  1987年   2870篇
  1986年   2855篇
  1985年   3142篇
  1984年   2976篇
  1983年   2668篇
  1982年   2519篇
  1981年   2463篇
  1980年   2318篇
  1979年   2760篇
  1978年   2460篇
  1977年   2376篇
  1976年   2208篇
  1975年   2447篇
  1974年   2619篇
  1973年   2544篇
  1972年   2107篇
  1971年   1948篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
The present study tested gender as a moderator of the relationship between race-related stress and mental health symptoms among African American adults. Because African American women are exposed to stressors associated with race and gender, we hypothesized that African American women would have higher levels of race-related stress and more severe mental health outcomes related to experiences of race-related stress compared to African American men. Multivariate analyses revealed that African American men had higher stress appraisals for institutional racism than did women. No significant gender differences were found for cultural and individual racism. Moderated regression analyses revealed that increases in stress appraisals for individual racism were associated with increases in anxiety and obsessive-compulsive symptoms for African American women. Race-related stress had no significant effects on mental health symptoms for African American men. The findings suggest that gender is an important factor in determining the impact of race-related stress on mental health.  相似文献   
4.
5.
6.
7.
8.
9.
The special composition question asks, roughly, under what conditions composition occurs. The common sense view is that composition only occurs among some things and that all and only ‘ordinary objects’ exist. Peter van Inwagen has marshaled a devastating argument against this view. The common sense view appears to commit one to giving what van Inwagen calls a ‘series‐style answer’ to the special composition question, but van Inwagen argues that series‐style answers are impossible because they are inconsistent with the transitivity of parthood. In what follows I answer this objection in addition to other, less troubling objections raised by van Inwagen.  相似文献   
10.
P A Kolers  M Green 《Perception》1984,13(3):249-254
Two shapes of either the same or different color will seem to be in smooth apparent motion with like-colored mates, at proper conditions of flash timing and spacing. An experiment is reported in which the condition was tested for unlike-colored pairs, for example red-green alternated with green-red. The question of interest was how the visual system would resolve the disparity of color. An 'intelligent' solution would rotate the shapes in three dimensions. Like-colored and unlike-colored parts were found to move and transform similarly, however, the resolution being dependent more upon timing than upon color. The motion of intelligence as it might be applied to vision is discussed in light of these results.  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