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   65804篇
  免费   2709篇
  国内免费   45篇
  68558篇
  2020年   767篇
  2019年   922篇
  2018年   1340篇
  2017年   1351篇
  2016年   1414篇
  2015年   975篇
  2014年   1157篇
  2013年   5628篇
  2012年   2101篇
  2011年   2327篇
  2010年   1370篇
  2009年   1346篇
  2008年   2011篇
  2007年   1979篇
  2006年   1727篇
  2005年   1571篇
  2004年   1542篇
  2003年   1413篇
  2002年   1440篇
  2001年   2248篇
  2000年   2154篇
  1999年   1578篇
  1998年   810篇
  1997年   707篇
  1996年   627篇
  1995年   623篇
  1994年   593篇
  1993年   620篇
  1992年   1278篇
  1991年   1202篇
  1990年   1210篇
  1989年   1105篇
  1988年   1068篇
  1987年   1040篇
  1986年   1053篇
  1985年   1092篇
  1984年   861篇
  1983年   746篇
  1982年   579篇
  1979年   816篇
  1978年   625篇
  1975年   743篇
  1974年   821篇
  1973年   758篇
  1972年   708篇
  1971年   626篇
  1969年   610篇
  1968年   716篇
  1967年   679篇
  1966年   624篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
This study examined individuals' tendencies to migrate from one organization to another (i.e., the propensity to switch employers). Previous researchers have suggested that switching organizations throughout the career span may be partially heritable and therefore related to individual differences in personality traits. If personality traits are indeed related to a tendency to turnover from organizations, this suggests that current procedures for calculating utility may be inaccurate. Using a database of 1081 individuals who have been in the workforce for several years, results indicated that personality traits measured by the Occupational Personality Questionnaire (non‐ipsative; OPQn) were modestly related to organization switching (i.e., repeated moves from organization to organization). We found that higher scores on extraversion, openness to experience, and conscientiousness‐related traits were modestly correlated with more frequent organization switching. However, we demonstrate that these modest relationships can produce large inaccuracies in utility estimates.  相似文献   
13.
14.
15.
16.
Using a Piagétan perspective, this study investigated the ways in which elementary school children perceive changes in the size of a televised image (in this case, a candy bar). The findings suggest that younger children perceive changes in image size from a medium shot to a close-up as changes in the object itself. Children's responses to changes in the televised image parallel their responses to traditional conservation tasks, but conservation of televised images occurs at a later age. In addition, children appear to use different cognitive skills to interpret how a zoom or a cut transforms the size of a televised image. When a zoom is used, children more readily perceive the object as “growing larger.”  相似文献   
17.
18.
19.
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   
20.
Three experiments, each using a single group of pigeons, are reported. In Experiment 1 subjects were initially trained with two stimuli, one of which was always followed by food, the other being reinforced according to a 50% partial reinforcement schedule. Subsequently a serial procedure was adopted in which an additional stimulus, C, was consistently followed by the partially reinforced CS. A second additional stimulus, A, was followed on half of its occurrences by the continuously reinforced CS, its remaining presentations being followed by nothing. The rate of autoshaped keypecking was substantially greater during A than during C. In the remaining experiments subjects received first-order conditioning with a single stimulus that was either partially (Experiment 2) or continuously (Experiment 3) reinforced. The stimuli A and C were then again introduced for serial autoshaping. Stimulus A was occasionally paired with the CS and occasionally followed by nothing, whereas stimulus C was always followed by the CS. As in Experiment 1, the rate of responding during A was greater than during C. It is proposed that one influence on the rate of autoshaped keypecking during a CS is the accuracy with which the immediate consequences of that CS are predicted.  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