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   7277篇
  免费   300篇
  国内免费   2篇
  2021年   67篇
  2020年   109篇
  2019年   103篇
  2018年   148篇
  2017年   149篇
  2016年   155篇
  2015年   112篇
  2014年   164篇
  2013年   777篇
  2012年   246篇
  2011年   270篇
  2010年   174篇
  2009年   191篇
  2008年   200篇
  2007年   248篇
  2006年   192篇
  2005年   208篇
  2004年   199篇
  2003年   183篇
  2002年   217篇
  2001年   112篇
  2000年   97篇
  1999年   109篇
  1998年   109篇
  1997年   116篇
  1996年   92篇
  1995年   97篇
  1994年   97篇
  1993年   119篇
  1992年   113篇
  1991年   91篇
  1990年   81篇
  1989年   88篇
  1988年   82篇
  1987年   98篇
  1986年   76篇
  1985年   74篇
  1984年   90篇
  1983年   90篇
  1982年   105篇
  1981年   89篇
  1980年   102篇
  1979年   97篇
  1978年   112篇
  1977年   106篇
  1976年   95篇
  1975年   113篇
  1974年   99篇
  1973年   76篇
  1971年   70篇
排序方式: 共有7579条查询结果,搜索用时 15 毫秒
151.
Some previous publications have indicated that the creative skills of chemists tend to decline once they are past their thirties or early forties. These conclusions have been based on such criteria of creativity as merit ratings, citations in the literature, etc. In the present study, patent records for all 89 professional men (mostly chemists and chemical engineers) in one division of a large industrial scientific organization were analyzed to determine whether creativity as measured by the production of patentable ideas tended to decrease with age, to increase, or to remain about the same. In the statistical treatment of data both longitudinal and cross-sectional methods were used. All the results were consistent in revealing no decline in creative productivity with increase in age, and indicated instead a tendency for productivity to increase as chemists mature.  相似文献   
152.
One-hundred fifty human Ss viewed 32 patterns under neutral (N), pleasingness (P), or interestingness (l) instructional sets. An analysis of variance indicated that patterns with larger areas were viewed longer than patterns with smaller areas under all conditions; however, this effect was more pronounced under the P and I conditions than under the N condition. Patterns containing 9-sided shapes were viewed longer than those containing 3-sided shapes under the N and I conditions, while the reverse was true for the P condition.  相似文献   
153.
When an observer is confronted with a stimulus pattern that in some aspect does not change over time, perception of that aspect of the pattern does change. This paper documents several different types of change, all of which progress linearly with the square root of the observing time. Examples are drawn from studies of figurai after-effects, motion after-effects, vigilance, motion neutralization, visibility of the stabilized retinal image, effects of contours on visibility and fluctuations in the perceptual organization of ambiguous figures.  相似文献   
154.
Data recently presented by Wilson (1965) seem to demonstrate the separate effects of adaptation and of after-effect repulsion during and following continued observation of a curved line. Inasmuch as the experiment was performed without apparent reference to the psychophysical theory of figural after-effects (Taylor, 1962), it is interesting to note that the results on adaptation agree qualitatively with one of the major presuppositions of the theory, and the results on repulsion agree quantitatively with its predictions.  相似文献   
155.
Visual form identification at brief durations was studied under: (a) monocular presentation; (b) dichopic presentation where the same form was presented successively on noncorresponding areas; and (c) dichopic presentation where the same form was presented on corresponding areas simultaneously and successively. Form identification for noncorresponding area dichopic presentation was at the level to be expected from 2independent chances to perceive. Both simultaneous and successive dichopic presentation on corresponding areas gave identification accuracy significantly above the level predicted by the assumption of independence. However, the binocular summation was not complete. When the same amount of energy entering the visual system in a binocular presentation was given in a monocular stimulation, the latter condition gave significantly better identification.  相似文献   
156.
A method of treating reading deficits based upon an extrinsic motivational system previously employed successfully with a single subject was extended to eighteen additional subjects. The junior-high age subjects included retarded children in special classes, several emotionally disturbed children, and culturally deprived children. The method of training used in the original study was designed to be simple to administer and simple to record the performance of the child. Thus, it was hypothesized that subprofessional personnel could be employed to administer the treatment. Adult volunteers and high school seniors were used as the therapy-technicians.

The eighteen Ss were given 38.2 hr of training in daily half-hour sessions, during which period the average reinforcement earned was $22.29. The mean number of single word reading responses was 94,425. The rate of reading accelerated over the period of training even though the reading material became more difficult. This occurred during a period when progressively less (about one-fourth as much) reinforcement was given per reading response. A mean of 593.5 new words were learned and 70.9 per cent of these were retained in a long-term test. The attention, attendance, cooperation, and diligent work behavior of the various children were maintained in good strength throughout the duration of the study. The results suggest that research be conducted to develop methods for treatment of behavioral deficits that can be widely applied by subprofessional therapy-technicians supervised by clinical psychologists.  相似文献   

157.
158.
159.
160.
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