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   61019篇
  免费   2471篇
  国内免费   23篇
  2020年   712篇
  2019年   842篇
  2018年   1226篇
  2017年   1238篇
  2016年   1281篇
  2015年   913篇
  2014年   1104篇
  2013年   5231篇
  2012年   2074篇
  2011年   2069篇
  2010年   1232篇
  2009年   1285篇
  2008年   1789篇
  2007年   1767篇
  2006年   1611篇
  2005年   1352篇
  2004年   1411篇
  2003年   1318篇
  2002年   1266篇
  2001年   2063篇
  2000年   1943篇
  1999年   1464篇
  1998年   678篇
  1997年   577篇
  1996年   659篇
  1995年   596篇
  1994年   594篇
  1993年   581篇
  1992年   1201篇
  1991年   1117篇
  1990年   1088篇
  1989年   1033篇
  1988年   998篇
  1987年   948篇
  1986年   946篇
  1985年   993篇
  1984年   817篇
  1983年   696篇
  1979年   838篇
  1978年   627篇
  1975年   667篇
  1974年   767篇
  1973年   787篇
  1972年   666篇
  1971年   618篇
  1970年   551篇
  1969年   542篇
  1968年   702篇
  1967年   604篇
  1966年   590篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
241.
Pigeons can discriminate locations presented in pictures   总被引:3,自引:3,他引:0       下载免费PDF全文
The present experiments were designed to teach pigeons to discriminate two locations represented by color photographs. Two sets of photographs were taken at two distinctive locations on a university campus. These sets represented several standpoints at each location. For the true-discrimination group, pictures from the two locations were differentially associated with reward; for the pseudodiscrimination group, half of the views from each location were arbitrarily but consistently associated with reward. The former group acquired the discrimination much more rapidly. These birds also showed good transfer to new views from the standpoints used in training and to a new standpoint at each location not used in training. In a second experiment, another group of pigeons could terminate any training trial by pecking an “advance” key. Three of 4 subjects used this option to reduce the duration of trials in which pictures from the negative location were presented. These data suggest that pigeons can integrate views shown in pictures into a “concept” of a location. The method used here may be the experimental analogue of a common, natural process by which animals learn to identify locations.  相似文献   
242.
In a study of air traffic controllers, religious differences are found in the way Type A behavior is associated with several health status indicators. Associations between the Jenkins Activity Survey (JAS) and physical illness incidence, health-promotive behavior, diastolic and systolic blood pressure, subjective distress and impulse control problems, and alcohol consumption are examined by religious attendance, religious affiliation, and change in affiliation. Findings confirm that Type A does not vary significantly by religion. However, there are several significant findings between Type A and various health indicators. Type A is associated with illness incidence, overall and more strongly in several religion, subgroups. Type A and alcohol consumption are related positively in Protestants and converts, and negatively in churchgoing Catholics. Type A is related to impulse control problems in churchgoing Protestants and to subjective distress in churchgoing Catholics. Finally, in individuals with weak or no religious ties, Type A is associated with lower blood pressure. This last finding suggests that in some people (for example, the irreligious or unchurched), the coronary-prone behavior pattern may have cardiovascular effects which are salutary in at least one respect.The authors wish to thank Dr. Kyriakos S. Markides and Laura A. Ray for their assistance with this study. Address requests for reprints to Dr. Levin at the Institute of Gerontology, 300 North Ingalls, Ann Arbor, MI 48109.  相似文献   
243.
244.
245.
Past research in referential communication has indicated normally developing children show developmental progression in ability to communicate a specific referent to a listener. In one paradigm subjects were given lists of word-pairs in which one member of each pair was designated as the referent. It was shown that communicating about referents found in word-pairs associated in some way was more difficult than communicating about referents in dissimilar word-pairs. The present study extended this methodology to learning-disabled children. Learning-disabled, language-learning-disabled, and normally achieving children were asked to communicate about 30 pictured referents on three different tasks. On Tasks 1 and 2 each subject was asked to give a clue for the referent that would distinguish it from the other picture. Stimuli for Task 1 were 30 pairs of pictures that were related in some way and the stimuli for Task 2 were 30 pairs of unrelated pictures. Task 3 required the subjects to evaluate the adequacy of the examiner's clues for Task 1 stimuli. The disabled subjects were matched to the normally achieving subjects on the basis of receptive vocabulary age. Few differences were noted among the groups' performances on these referential communication tasks. Implications include the importance of vocabulary and concept development to referential communication.  相似文献   
246.
There are increasing numbers of self-referral stress-management programs, a few of which use group-relaxation techniques, but few data are available on the personalities of the symptomatic and asymptomatic clients who attend or on any changes in personality after the program. Scores on the Eysenck Personality Inventory, Multiple Health Locus of Control, and State-Trait Anxiety Inventory as well as demographic information were obtained from 255 adults who attended a 10-session, university-based, group-relaxation program. The symptomatic clients reported significantly less anxiety, less neuroticism, were more extraverted and ascribed less of their behavior to chance at a 1 month post-treatment follow-up than at intake. The small group of asymptomatic clients also reported less anxiety and neuroticism at the follow-up. There were no sex differences on the Eysenck inventory or the anxiety scales but there were for the Multiple Health internal and control scales. It was concluded that group relaxation appeared to improve mental health scores effectively for both stressed and nonstressed adults and that age was significantly related to some personality scores.  相似文献   
247.
This report examines two methodologic concerns pertaining to use of the cloze procedure in studying the predictability of schizophrenic speech, scoring criteria and raters' education (at or below college level). We find that two strategies for scoring the predictions of raters, one requiring the exact word, the other permitting a reasonable synonym, do not appear to differ in distinguishing groups of patients. The accuracy of raters' guessing is, however, correlated with raters' education: the more educated the rater, the more accurate the guessing. Thought-disordered schizophrenic speech is significantly less predictable than that of nonthought-disordered schizophrenics and normal controls when scored by less educated raters. These differences diminish when more highly educated raters are used. We conclude that raters' education can influence the sensitivity of cloze analysis.  相似文献   
248.
32 children 5 to 6 yr. old, 32 9 to 11 yr. old, and 32 adults linked musical fragments to emotions in a similar manner, older subjects being more accurate. Some emotions were more difficult than others; anger and fear were often confused. Older subjects gave better justifications for their choices.  相似文献   
249.
We hypothesized that in the decodification of connotative aspects of visual chromatic stimuli the periphery of the body plays an important role. In particular we hypothesized that the decodification process of so called "warm" and "cold" colours is related to a real modification of the temperature of the body which is the basis of the "subjective feeling" and of the attribution of the "emotional meaning" to the stimulus. So we have measured the temperature of the body of 36 female psychology students while they were looking at a luminous screen through spectacles in which filters (coloured lenses) of different colours were placed. Analysis indicated that during the perception of so called "warm" colours a statistically significant increase in the temperature of the body appeared. We observed an enhancement of temperature on the left side of the body during the perception with red and yellow filters and a small increase in temperature on the right side of the body with orange and yellow filters. In the discussion of the results we considered also the role of the cerebral dominance in decodification process of the connotative components of stimuli.  相似文献   
250.
Performance of two groups of youngsters, educable mentally retarded (CA 15-5; MA 11-4; IQ 74.3) and those of average ability (CA 10-5; MA 11-3; IQ 109.1) was compared for intentional and incidental visual memory as a function of cognitive level and color of the stimulus. Nonretarded subjects performed significantly better than the retarded ones of equal MA. Both groups performed better with a color than black-white card, and both groups did better on the tasks involving intentional rather than incidental memory.  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