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   59606篇
  免费   2097篇
  国内免费   30篇
  2020年   589篇
  2019年   741篇
  2018年   2226篇
  2017年   2086篇
  2016年   1854篇
  2015年   777篇
  2014年   925篇
  2013年   4584篇
  2012年   1877篇
  2011年   2704篇
  2010年   1986篇
  2009年   1557篇
  2008年   2273篇
  2007年   2459篇
  2006年   1431篇
  2005年   1374篇
  2004年   1319篇
  2003年   1181篇
  2002年   1211篇
  2001年   1769篇
  2000年   1675篇
  1999年   1274篇
  1998年   671篇
  1997年   580篇
  1996年   519篇
  1995年   518篇
  1994年   497篇
  1993年   518篇
  1992年   1015篇
  1991年   956篇
  1990年   949篇
  1989年   852篇
  1988年   817篇
  1987年   810篇
  1986年   806篇
  1985年   858篇
  1984年   670篇
  1983年   579篇
  1982年   470篇
  1979年   658篇
  1978年   488篇
  1976年   451篇
  1975年   592篇
  1974年   623篇
  1973年   601篇
  1972年   540篇
  1971年   476篇
  1968年   545篇
  1967年   542篇
  1966年   477篇
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
31.
32.
33.
Gay marriages (as such) are not as yet allowed anywhere but the demand for them is increasing. Most countries take a liberal attitude towards marriage: few obstacles are put in its way. But objections to gay marriages continue to be raised. These objections are refuted and the case for gay marriage is assessed through the prism of various forms of liberalism. The normative argument for allowing gay marriage is shown to be both strong and consistent with many of the values upheld by the opponents of such unions.  相似文献   
34.
In three experiments we studied the relationship between contextual conditioning and the reinstatement of extinguished lever pressing that occurs when noncontingent food is introduced following extinction. In all three experiments the non-contingent food was presented off-baseline (with the response levers not present). On subsequent tests, with the response levers present, animals that had been exposed to food showed more reinstatement of lever pressing than control animals. This finding rules out alternative mechanisms for the reinstated responding that rely on the interaction of non-contingent food and responding, such as superstitious reinforcement or the discriminative after-effects of food. In addition, in each experiment we demonstrated that manipulations known to affect contextual conditioning (signalling the food in Experiment 1, context extinction in Experiment 2, and switching contexts in Experiment 3) reduced the reinstatement. These results are consistent with the claim that contextual conditioning is important in controlling instrumental conditioning and closely parallel findings concerning the reinstatement of Pavlovian responsing following extinction.  相似文献   
35.
36.
37.
This study evaluated cardiovascular responses (CVR) to an active speech task with blatantly discriminatory (BRC) versus neutral (NRC) stimuli and an anger recall task in a sample of Black men (N = 73; age 18 to 47). Diastolic blood pressure scores were higher for NRC versus BRC stimuli during anger recall (p = .05). Moreover, persons in the NRC group who perceived high levels of racism (vs. no racism or BRC group) during active speech showed larger increases in blood pressure across postspeech rest, anger recall, and subsequent rest (p = .03). The notable elevation in CVR in response to an ambiguous event extends current models of racism suggesting that subtle racism is a psychosocial stressor that erodes health through chronically elevated CVR.  相似文献   
38.
39.
40.
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