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   54522篇
  免费   2138篇
  国内免费   15篇
  56675篇
  2019年   625篇
  2018年   859篇
  2017年   907篇
  2016年   909篇
  2015年   650篇
  2014年   838篇
  2013年   3987篇
  2012年   1482篇
  2011年   1585篇
  2010年   1003篇
  2009年   949篇
  2008年   1447篇
  2007年   1372篇
  2006年   1302篇
  2005年   1145篇
  2004年   1156篇
  2003年   1076篇
  2002年   1128篇
  2001年   1549篇
  2000年   1468篇
  1999年   1142篇
  1998年   611篇
  1997年   563篇
  1996年   554篇
  1992年   982篇
  1991年   939篇
  1990年   914篇
  1989年   908篇
  1988年   916篇
  1987年   853篇
  1986年   910篇
  1985年   953篇
  1984年   779篇
  1983年   715篇
  1982年   577篇
  1981年   573篇
  1979年   887篇
  1978年   669篇
  1977年   570篇
  1976年   616篇
  1975年   727篇
  1974年   858篇
  1973年   916篇
  1972年   709篇
  1971年   701篇
  1970年   679篇
  1969年   713篇
  1968年   860篇
  1967年   768篇
  1966年   779篇
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
911.
A survey of published and private opinions of mental health professionals revealed a previously hidden consensus concerning certain values that enhance mental health. These values concern Freedom, Love, Identity, Truth, Universals, Symptom Management, and Work. There was disagreement about the effect of many other values on mental health. It is my contention that values permeate counseling and psychotherapy, that the values of conselors and therapists should be more explicit, and that values should be openly used to guide and evaluate treatment.  相似文献   
912.
The accuracy and response latency of absolute frequency judgments were measured as a function of test lag (the number of intervening items between presentations of a test item) in a continuous memory task. Frequency was varied from one to three presentations in Experiments 1 and 2 and from one to five presentations in Experiment 3. The proportion of correct responses decreased as frequency increased, and correct mean response time tended to increase with frequency. Both accuracy and correct mean response time were found to be largely a function of the most recent test lag. The lag-latency functions were best described by piecewise linear functions, with the breakpoint occurring between lags 1 and 2. Continuous frequency estimation was also shown to improve with extended practice. The implications of the results are discussed with reference to trace strength, numerical-inference, and multiple-trace theories of frequency discrimination.  相似文献   
913.
914.
The performance of poor and normal sixth-grade readers was compared on an auditory short-term memory task in two studies. In the first study, the effects of distraction, list length, and speed of stimulus presentation were investigated to test the hypothesis that the performance of the poor readers is affected by deficits in selective attention. Group differences in performance, however, were obtained for both distraction and no-distraction conditions. The second experiment examined the hypothesis that group differences may reflect differences in the use of rehearsal. In the second experiment, half the reading-disabled children and half the controls were provided with rehearsal training prior to completing the same short-term memory task a second time. Rehearsal training resulted in improved performance relative to children who were not trained; however, there was no rehearsal training x reading group interaction. The poor readers continued to show deficits in performance relative to the performance of control children. The results of these two studies suggest that deficits observed for poor readers on short-term memory tasks may reflect processing difficulties in some area that precedes rehearsal and affects performance under both distraction and no-distraction conditions.The authors wish to express their thanks to the Sachem School District and Betty Gould, Nicholas Opinanate, and Guy Barber for their unlimited cooperation, and to John Neale for very helpful discussions of a number of issues in this paper.  相似文献   
915.
The relationship of self-concept (self-esteem and mastery) and social support to psychological distress was studied among 68 Israeli women immediately prior to undergoing biopsy for suspected cancer (acute stress) and 3 months later for the noncancer group (everyday stress). It was predicted that women with stronger self-concepts and more social support would experience less state depression and state anxiety during the acute crisis than women with weaker self-concepts and less social support. It was further predicted that self-concept would be more critical than social support due to the acute nature of the event. Finally, self-concept was predicted to be related to psychological distress both during the acute and everyday stress situations (a direct effect), while social support was predicted to be related to psychological distress only during the acute stress situation (a buffering effect). The hypotheses were generally confirmed. However, self-concept and social support were seen as complexly related to psychological distress during the acute phase, one not necessarily being more critical than the other. The selective employment of available resistance resources to fit the situation and implications for preventive intervention were discussed.  相似文献   
916.
917.
918.
919.
Periadolescent rats exhibit a number of behavioral differences in comparison with younger or older animals. For instance, periadolescents tend to show enhanced acquisition of simple active avoidance tasks, but impaired acquisition of more complex appetitive and aversive discriminations. In this experiment, rats were trained on a simple passive avoidance task at one of three ages, as weanlings (25 days), periadolescents (35 days), or young adults (45 days). Training occurred in the presence of both a redundant discriminative stimulus and a specified, redundant contextual stimulus. The periadolescents did not differ from either younger or older rats in rate of learning the passive avoidance task. The retention performance of these animals was then tested following a change in either, neither, or both of the redundant cues. When a measure of performance that controls for baseline activity was used, it was observed that periadolescents were not disrupted by a change in the redundant discriminative stimulus, a cue change that clearly disrupted performance in 25- and 45-day-old animals, and tended to be more disrupted by the contextual change than younger or older rats. It is hypothesized that the alterations in performance exhibited by periadolescents may be related to an ontogenetic alteration in stimulus selection modulated by the catecholaminergic systems.  相似文献   
920.
Robust lateralization developed in right-handed adults who were asked to judge letter pairs as "same" or "different" during 4608 trials. By the end of the first two blocks (768 trials) "same" responses were favored when presented in the RVF (transmitted directly to the left hemisphere) and "different" responses were favored when presented in the LVF (transmitted direction to the right hemisphere). This gradually reversed over sessions with "same" responses becoming faster for letters presented in the LVF, and "different" responses becoming faster for stimuli presented in the RVF. The laterality acquired under these conditions was cumulative and reproducible, appeared in all 16 subjects, and was preserved between sessions a week apart. The data suggest that laterality is a flexible and reversible characteristic of the human brain even when stimulus and task remain constant.  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