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   24133篇
  免费   865篇
  国内免费   11篇
  25009篇
  2020年   235篇
  2019年   243篇
  2018年   380篇
  2017年   405篇
  2016年   409篇
  2015年   260篇
  2014年   343篇
  2013年   1846篇
  2012年   675篇
  2011年   724篇
  2010年   455篇
  2009年   411篇
  2008年   634篇
  2007年   614篇
  2006年   560篇
  2005年   495篇
  2004年   477篇
  2003年   442篇
  2002年   499篇
  2001年   774篇
  2000年   781篇
  1999年   596篇
  1998年   278篇
  1997年   232篇
  1992年   478篇
  1991年   425篇
  1990年   462篇
  1989年   432篇
  1988年   414篇
  1987年   418篇
  1986年   428篇
  1985年   443篇
  1984年   349篇
  1983年   316篇
  1982年   255篇
  1981年   231篇
  1979年   400篇
  1978年   304篇
  1977年   273篇
  1976年   240篇
  1975年   360篇
  1974年   390篇
  1973年   364篇
  1972年   342篇
  1971年   304篇
  1970年   266篇
  1969年   333篇
  1968年   380篇
  1967年   335篇
  1966年   337篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
OBJECTIVE: To test a theoretical model of how ethnic pride and self-control are related to risk and protective factors. DESIGN: A community sample of 670 African American youth (mean age = 11.2 years) were interviewed in households. MAIN OUTCOME MEASURES: Measures of cigarette smoking, alcohol use, and sexual behavior (lifetime to past month). RESULTS: Structural modeling analyses indicated parenting was related to self-control and self-esteem, and racial socialization was related to ethnic pride. Self-control and self-esteem variables were related to levels of deviance-prone attitudes and to perceptions of engagers in, or abstainers from, substance use and sexual behavior. The proximal factors (behavioral willingness, resistance efficacy, and peer behavior) had substantial relations to the criterion variables. Participant gender and parental education also had several paths in the model. Results were generally similar for the 2 outcome behaviors. CONCLUSIONS: In this population, self-esteem and self-control are related to parenting approaches and have pathways to attitudes and social perceptions that are significant factors for predisposing to, or protecting against, early involvement in substance use and sexual behavior.  相似文献   
2.
3.
Subjects in five experiments read nine-digit memory lists from a cathode ray tube for immediate recall. Reading aloud always produced a localized and reliable advantage for the last item, compared to reading silently. Two experiments on whispered and mouthed lists, with or without simultaneous broadband noise, falsified expectations derived from the theory of precategorical acoustic storage. Three additional experiments showed no enhancement of recency in the silent conditions when the digits were drawn or spelled gradually on the screen, a result that is inconsistent with the changing-state hypothesis. The classic auditory-visual modality effect is large and reliable, but still poorly understood.  相似文献   
4.
We investigated whether young children are able to infer affiliative relations and relative status from observing others' imitative interactions. Children watched videos showing one individual imitating another and were asked about the relationship between those individuals. Experiment 1 showed that 5‐year‐olds assume that individuals imitate people they like. Experiment 2 showed that children of the same age assume that an individual who imitates is relatively lower in status. Thus, although there are many advantages to imitating others, there may also be reputational costs. Younger children, 4‐year‐olds, did not reliably make either inference. Taken together, these experiments demonstrate that imitation conveys valuable information about third party relationships and that, at least by the age of 5, children are able to use this information in order to infer who is allied with whom and who is dominant over whom. In doing so, they add a new dimension to our understanding of the role of imitation in human social life.  相似文献   
5.
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   
6.
7.
Rats' lever presses on a retractable lever earned brief presentations of discriminative stimuli signalling periods in which responding on an alternative lever was either non-reinforced (extinction) or reinforced on a random ratio schedule. The predictions of two theoretical accounts of this behaviour were tested by studying the effects of omitting either the stimulus signalling the reinforced or that signalling the non-reinforced schedule component. Under these conditions rats' behaviour is determined by the conditioned, affective properties of the stimuli rather than by their purely informational properties.  相似文献   
8.
9.
10.
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