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   72412篇
  免费   2775篇
  国内免费   39篇
  2020年   784篇
  2019年   942篇
  2018年   1386篇
  2017年   1411篇
  2016年   1503篇
  2015年   979篇
  2014年   1235篇
  2013年   6145篇
  2012年   2262篇
  2011年   2438篇
  2010年   1448篇
  2009年   1437篇
  2008年   2169篇
  2007年   2153篇
  2006年   1896篇
  2005年   1720篇
  2004年   1678篇
  2003年   1563篇
  2002年   1607篇
  2001年   2316篇
  2000年   2232篇
  1999年   1692篇
  1998年   900篇
  1997年   770篇
  1996年   706篇
  1995年   687篇
  1994年   674篇
  1993年   700篇
  1992年   1371篇
  1991年   1283篇
  1990年   1307篇
  1989年   1189篇
  1988年   1144篇
  1987年   1140篇
  1986年   1129篇
  1985年   1214篇
  1984年   948篇
  1983年   836篇
  1982年   685篇
  1979年   990篇
  1978年   741篇
  1975年   896篇
  1974年   944篇
  1973年   906篇
  1972年   822篇
  1971年   722篇
  1969年   706篇
  1968年   840篇
  1967年   815篇
  1966年   747篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
201.
202.
203.
This research tested the hypothesis that children's perceptions of academic competence and their personal control over school-related performance affects subsequent intrinsic interest and preference for challenge in an evaluative setting. In a correlational study, children's self-reported perceptions of academic competence and personal control were found to relate positively to their intrinsic interest in schoolwork and preference for challenging school activities. A subset of this sample was exposed to varying levels of a controlling directive, and preference for challenge was assessed behaviorally during a free-choice period in which subjects were unaware that they were being observed. As predicted, the data indicated that when given the evaluative, controlling directive, children who had high perceptions of academic competence and control preferred a greater challenge than did children whose perceptions were low on these measures. No difference between groups in terms of preference for challenge was evident when no controlling directive was presented. These findings are discussed in terms of theories of intrinsic motivation and potential processes that underly these effects.  相似文献   
204.
205.
Subjects (N= 28) performing a complex disjunctive concept-formation task on a microcomputer were given the opportunity to seek help following failure to correctly identify concepts. The proportion of those seeking help was significantly greater when the source of help was the computer itself (86%) rather than another person (36%). Consistent with past research, those who did not ask for help gave reasons other than the potential negative social consequences of doing so. Self-report data and a systematic test for the presence of experimenter-induced demand ruled out several possible sources of confounding. The results have implications for designers of time-sharing and networked computer systems.  相似文献   
206.
Social status variables have been shown to influence attributional judgments, but their effects have been demonstrated almost entirely in experimental settings. The influence of such statuses in experimental settings may differ from their influence in natural settings. We examined the influence on attributional judgments of the status characteristics of both subjects and actors in conjunction with variations in the degree of “real world” characteristics of both subjects and social context. These comparisons were drawn through a partial replication of earlier research investigating the effects of a social status variable, victim sex, and a situational variable—type of assault—on attributions about an assault victim. The social status characteristic, victim sex, had less influence on attributions in an adult juror sample than in a student sample and testimony-related characteristics were more influential in the adult juror sample than in the student sample. Thus, the categories of variables that influence attributions appear to depend on the context of judgment and on the breadth of subjects' life experience. These findings are discussed and we conclude with the caution that careful identification of the differences produced by context and subject characteristics is necessary to support generalization of laboratory-based research.  相似文献   
207.
The relative importance of genetic and environmental factors for neuroticism, extraversion, impulsivity, and monotony avoidance were estimated in a sample of 99 monozygotic and 229 dizygotic pairs of twins reared apart (TRA) and a matched sample of 160 monozygotic and 212 dizygotic pairs of twins reared together (TRT). The average age was 58.6 (SD = 13.6); 72% of the twins were 50 or older. Model-fitting analyses verified the importance of genetic factors for all four measures; from 23% to 45% of the total variation was attributable to genetic sources. There was considerable evidence that these factors were operating in a nonadditive manner for extraversion and impulsivity. Shared environment accounted for less than 10% of the variance; some evidence for selective placement was found for neuroticism.  相似文献   
208.
A modification of the procedure originally used by Davidson, Suppes, and Siegel (1956) to measure subjective utility was used to study the influence of positive affect on individuals' perceived value (utility) functions. Results indicated, as expected, that persons in whom positive affect had been induced showed a more negative subjective utility for losses than did controls. This indicates that losses seem worse to people who are feeling happy than to those in a control condition. The subjective utility functions of the two groups did not differ as much, however, when people were considering potential gain. Thus, at least in the situation tested in this study, potential gains did not seem to be more appealing (nor less so) for affect subjects than they did for controls. These findings are discussed in relation to theoretical issues in decision making and work suggesting that positive affect can promote increased sensitivity to losses in situations of potential meaningful loss.  相似文献   
209.
The recognition of threatening facial stimuli   总被引:1,自引:0,他引:1  
Two studies examined the information that defines a threatening facial display. The first study identified those facial characteristics that distinguish between representations of threatening and nonthreatening facial displays. Masks that presented either threatening or nonthreatening facial displays were obtained from a number of non-Western cultures and scored for the presence of those facial features that discriminated between such displays in the drawings of two American samples. Threatening masks contained a significantly higher number of these characteristics across all cultures examined. The second study determined whether the information provided by the facial display might be more primary nonrepresentational visual patterns than facial features with obvious denotative meaning (e.g., diagonal lines rather than downturned eyebrows). The subjective response to sets of diagonal, angular, and curvilinear visual stimuli revealed that the nonrepresentational features of angularity and diagonality in the visual stimulus appeared to have the ability to evoke the subjective responses that convey the meaning of threat.  相似文献   
210.
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