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   62985篇
  免费   2524篇
  国内免费   32篇
  2020年   700篇
  2019年   879篇
  2018年   1255篇
  2017年   1272篇
  2016年   1342篇
  2015年   918篇
  2014年   1138篇
  2013年   5785篇
  2012年   2019篇
  2011年   2209篇
  2010年   1307篇
  2009年   1336篇
  2008年   2025篇
  2007年   1976篇
  2006年   1778篇
  2005年   1643篇
  2004年   1612篇
  2003年   1495篇
  2002年   1564篇
  2001年   1939篇
  2000年   1803篇
  1999年   1438篇
  1998年   848篇
  1997年   761篇
  1996年   660篇
  1995年   675篇
  1994年   641篇
  1993年   673篇
  1992年   1153篇
  1991年   1077篇
  1990年   1067篇
  1989年   962篇
  1988年   914篇
  1987年   917篇
  1986年   905篇
  1985年   986篇
  1984年   837篇
  1983年   746篇
  1982年   639篇
  1981年   581篇
  1979年   764篇
  1978年   642篇
  1977年   554篇
  1976年   587篇
  1975年   713篇
  1974年   758篇
  1973年   689篇
  1972年   608篇
  1968年   599篇
  1967年   581篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
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   
52.
53.
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   
54.
55.
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   
56.
57.
58.
59.
60.
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