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   75720篇
  免费   2413篇
  国内免费   21篇
  2020年   705篇
  2019年   833篇
  2018年   4282篇
  2017年   3699篇
  2016年   3235篇
  2015年   1090篇
  2014年   1149篇
  2013年   5058篇
  2012年   2495篇
  2011年   4133篇
  2010年   3490篇
  2009年   2596篇
  2008年   3292篇
  2007年   3680篇
  2006年   1565篇
  2005年   1502篇
  2004年   1501篇
  2003年   1379篇
  2002年   1280篇
  2001年   1974篇
  2000年   1863篇
  1999年   1384篇
  1998年   666篇
  1997年   576篇
  1996年   631篇
  1995年   563篇
  1994年   564篇
  1993年   553篇
  1992年   1115篇
  1991年   1027篇
  1990年   1017篇
  1989年   974篇
  1988年   943篇
  1987年   873篇
  1986年   873篇
  1985年   924篇
  1984年   746篇
  1983年   644篇
  1982年   484篇
  1979年   764篇
  1978年   571篇
  1975年   603篇
  1974年   682篇
  1973年   705篇
  1972年   604篇
  1971年   562篇
  1970年   483篇
  1968年   607篇
  1967年   526篇
  1966年   504篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
992.
993.
The present study was designed to explore both the predictors of ethnic identity and the relationship between ethnic identity and psychosocial adjustment. Perceptions of ethnicity and ethnic identity and measures of psychosocial adjustment were obtained from 82 Italian-Australian adolescents. Parents' maintenance of cultural ties was associated with a strong sense of ethnic identity, however ethnic identity was relatively unimportant in predicting psychosocial adjustment. Cultural variables such as parents' embeddedness in the Italian community, the desire to assimilate into the Australian culture, and the perception of problems arising from minority group membership were of greater significance.  相似文献   
994.
A new test for measuring the ability to perceive pictorial depth was used with children of two remote Bushman populations (!Xu and Kxoe), as well as with a sample of adult Bushmen drawn from these populations and a sample of urban Zulu children. The results show that subjects of apparently little sophistication are capable of perceiving depth when confronted with a ‘geometric’ figure. They also show surprising inter-group differences which cannot be easily explained by differences of environmental experience.  相似文献   
995.
Autobiographical memory in suicide attempters   总被引:4,自引:0,他引:4  
  相似文献   
996.
997.
The role of on-the-job experience in fostering skill at detecting deception was examined. A deception-detection test was administered to three samples of more than 100 subjects each: a group of undergraduates with no special experiences at detecting deceit; a group of new recruits to a federal law enforcement training program, who had some limited on-the-job experience at detecting deceit; and a group of advanced federal law enforcement officers, with years of experience working at jobs in which the detection of deception is very important. Although the officer samples were more confident about their judgments of deceptiveness than were the students, they were no more accurate than the students. None of the three groups showed a significant improvement in deception-detection success from the first half to the second half of the test; however, the advanced officers felt increasingly confident about their performance as they progressed through the test. Correlational analyses of the relationship between accuracy and confidence provided further evidence that experience does not improve people's awareness oi the accuracy or inaccuracy of their judgments. The findings from this research are compared to the results of research on other kinds of professional decision-makers (e.g., clinical psychologists), and several theoretical perspectives on the role of experience in decision making are discussed.  相似文献   
998.
We examined the effects of assigning a classroom manager's role on the frequency of social interactions and the sociometric standing of three withdrawn kindergarten students. Results showed that when the three socially withdrawn students were placed in the manager's role they substantially increased the frequency of their positive social initiations during free-play time, were the recipients of many more positive and significantly fewer negative social bids from their peers, were rated more favorably by their classmates on a sociometric rating scale, and were selected more frequently as best friends by their peers. In addition, follow-up data suggested partial maintenance of treatment effects when students no longer occupied manager positions.  相似文献   
999.
Pigeon's observational learning of successive visual discrimination was studied using within-subject comparisons of data from three experimental conditions. Two pairs of discriminative stimuli were used; each bird was exposed to two of the three experimental conditions, with different pairs of stimuli used in a given bird's two conditions. In one condition, observers were exposed to visual discriminative stimuli only. In a second condition, subjects were exposed to a randomly alternating sequence of two stimuli where the one that would subsequently be used as S+ was paired with the operation of the grain magazine. In a third experimental condition, subjects were exposed to the performance of a conspecific in the operant discrimination procedure. After exposures to conspecific performances, there was facilitation of discriminative learning, relative to that which followed exposures to stimulus and reinforcement sequences or exposures to stimulus sequences alone. Exposure to stimulus and food-delivery sequences enhanced performance relative to exposure to stimulus sequences alone. The differential effects of these three types of exposure were not attributable to order effects or to task difficulty; rather, they clearly were due to the type of exposure.  相似文献   
1000.
The possible role of "effort" in the accuracy of pigeons' performance on a delayed matching-to-sample procedure was investigated by examining the effects of response requirements that accompanied a trial-initiating stimulus and that accompanied a sample stimulus. In the first experiment, the effect of varying the size of a fixed-ratio requirement for responses during an initiating stimulus was compared to that of varying a similar requirement for responses during the sample stimulus. Accuracy increased reliably with increases in the ratio scheduled during the sample stimulus, but was not significantly affected by increases in the ratio scheduled on the key during the initiating stimulus. In another phase of Experiment 1, sample duration was held constant while the ratio requirement was varied during the initiating stimulus. Again, accuracy of matching to sample was not significantly affected by the size of the ratio scheduled during the initiating stimulus. Experiment 2 provided a systematic replication of these results in another group of pigeons and included a more detailed analysis of responding. These results support the view that increases in sample-response requirement facilitate accuracy of delayed matching by increasing the durations of exposure to the sample stimuli, and do not support a role of effort in the sample-response effect. In Experiment 3, the facilitative effect of responses on the sample but not of those on the initiating stimulus was replicated using a simultaneous matching-to-sample procedure. This finding provides further evidence against an interpretation of response-requirement effects that appeals to effort; the finding also suggests that sample exposure might affect initial discrimination of the sample rather than remembering the sample.  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