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   213343篇
  免费   8944篇
  国内免费   164篇
  2020年   2815篇
  2019年   3488篇
  2018年   4050篇
  2017年   4452篇
  2016年   4973篇
  2015年   3966篇
  2014年   4823篇
  2013年   23561篇
  2012年   5945篇
  2011年   5551篇
  2010年   4576篇
  2009年   5122篇
  2008年   5537篇
  2007年   5168篇
  2006年   5286篇
  2005年   5121篇
  2004年   4587篇
  2003年   4181篇
  2002年   4026篇
  2001年   5098篇
  2000年   4897篇
  1999年   4264篇
  1998年   3020篇
  1997年   2783篇
  1996年   2697篇
  1995年   2539篇
  1994年   2498篇
  1993年   2443篇
  1992年   3534篇
  1991年   3404篇
  1990年   3248篇
  1989年   3076篇
  1988年   3041篇
  1987年   2982篇
  1986年   2971篇
  1985年   3232篇
  1984年   3051篇
  1983年   2724篇
  1982年   2570篇
  1981年   2506篇
  1980年   2346篇
  1979年   2876篇
  1978年   2534篇
  1977年   2406篇
  1976年   2263篇
  1975年   2580篇
  1974年   2782篇
  1973年   2694篇
  1972年   2226篇
  1968年   2084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