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   38812篇
  免费   921篇
  国内免费   15篇
  2021年   161篇
  2020年   261篇
  2019年   298篇
  2018年   3775篇
  2017年   3142篇
  2016年   2588篇
  2015年   528篇
  2014年   443篇
  2013年   1698篇
  2012年   1207篇
  2011年   3055篇
  2010年   2866篇
  2009年   1837篇
  2008年   2212篇
  2007年   2641篇
  2006年   501篇
  2005年   634篇
  2004年   570篇
  2003年   487篇
  2002年   458篇
  2001年   770篇
  2000年   795篇
  1999年   511篇
  1998年   238篇
  1997年   220篇
  1996年   172篇
  1993年   158篇
  1992年   388篇
  1991年   344篇
  1990年   367篇
  1989年   362篇
  1988年   332篇
  1987年   305篇
  1986年   327篇
  1985年   326篇
  1984年   258篇
  1983年   219篇
  1981年   151篇
  1979年   205篇
  1978年   173篇
  1975年   197篇
  1974年   250篇
  1973年   208篇
  1972年   208篇
  1971年   174篇
  1970年   151篇
  1969年   202篇
  1968年   205篇
  1967年   166篇
  1966年   186篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
The effect of a digital block on the voluntary positioning of the index finger from a point of extreme extension through 45° flexion was examined in 12 subjects. A xylocaine ring block of the second proximal interphalangeal joint was used to eliminate the joint receptors while weights were attached to the finger. An inverse relationship was found between weight and distance moved when the subject was required to move the index finger of the nonpreferred hand to the required position. The results indicate that the muscular system is ancillary to the joint system in proprioceptive space perception.  相似文献   
992.
Sixteen observers palpated silicone models of human breasts containing lumps 1.6-12.1 mm in diameter. Detectability depended on the size of the lump, producing a systematic psychometric function. In eight observers who participated in three or more sessions, performance improved with practice, with most improvement occurring within one or two 26-trial sessions. Three-week retention measures disclosed no appreciable decrease in performance, but a significant correlation was found between the number of lumps detected and duration of trial (p < .01). There was no difference in performance between four observers who used their preferred hands and four observers who used their nonpreferred hands. These data establish that examination of breast models for the detection of lumps simulating cancer is a task amenable to experimental analysis.  相似文献   
993.
This study was designed to assess the extent to which social role and “just world” considerations would affect perceptions and attributions of responsibility to a rape victim. The rape victim was either a topless-bottomless dancer, a social worker, or a Catholic nun, and she was either acquainted or unacquainted with her assailant. In the acquainted condition, the dancer was attributed the greatest and the nun the least amount of responsibility, indicating that social role factors can govern the range of attributional judgments which might be made in any given instance. However, unacquainted victims were ascribed more responsibility for the rape than were acquainted victims, a difference which was significant when the victim was the nun. The latter findings are discussed in terms of Lerner's just world hypothesis. Significant sex differences were found in subjects' perceptions of and responses to the rape incident and, contrary to earlier findings, no relationship was found between victim attractiveness and punitiveness toward the wrongdoer.  相似文献   
994.
A group of 16 children from a normal community population was compared with two groups of 16 children referred for clinical evaluation of hyperactivity. These three groups were matched on age, sex, and race. One of the clinic groups was matched with the community sample on IQ and social class as well, while the children in the other clinic group were mentally retarded and of somewhat lower social class. All children were observed in a standardized playroom for two 15-minute sessions, one under free play instructions and the other under instructions restricting activity and toy-changing behavior. The two groups of children referred for evaluation of hyperactivity had significantly higher playroom activity scores than controls under both instructional conditions and significantly higher toy-change scores under restrictive instructions. Parental ratings of activity were also significantly higher in both clinic groups than in the community group. The mentally retarded clinic sample did not differ from the other clinic sample on any of the measures of activity or toy switching.A preliminary version of this article was presented at the meeting of the American Psychological Association, Chicago, Illinois, August 30, 1975, as part of a Symposium on Hyperactive Children: Assessment, Treatment, and Outcome. This research was supported by U. S. Public Health Service, Maternal and Child Health Project No. 916 and by Grants HD-03110 and ES-01104.  相似文献   
995.
Recognition memory for pictures was tested using matrices of 0s and 1s as stimuli in two experiments. In the first experiment dimensionality of matrices was varied (5 X 5 and 10 X 10 matrices). The results showed better recognition memory for 10 X 10 matrices. The second experiment investigated the importance of certain areas, such as center or surround, using 10 X 10 matrices only. The results suggested that neither center nor surround is given unusual weight.  相似文献   
996.
The dichotomies verbal/visuospatial, serial/parallel and analytic/holistic are reviewed with respect to differences in hemispheric processing. A number of experimental parameters may be varied in such tasks, and together with certain frequently-occurring weaknesses of experimental design may account for the often discrepant results hitherto reported. The above factors are systematically reviewed, and three further experiments are reported which attempt to fill in the missing designs. Further evidence is given in support of the hypothesis that right-hemisphere superiority is most apparent in processes leading to identity matching. It is quantitative rather than qualitative, and may depend upon operations on the entire gestalt, such as holistic matching, mental rotation, reflection, distortion, etc., rather than, e.g., simultaneous (parallel) processing of discretely analysed or isolated features or elements. On the other hand left-hemisphere involvement in visuospatial processing is thought to reflect analysis of the configuration into its separable components; such processing may be either serial or parallel, and may frequently lead to a judgement different.  相似文献   
997.
Schoolchildren, aged 16 years showed poorer incidental learning for nouns if the orienting task was one of finding rhymes for the items compared to assigning each word to a semantic category. On a recognition task including homophone and synonym foils, rhyming subjects made significantly more phonemic errors, whereas categorizing subjects produced a significantly greater number of semantic confusions. Subjects instructed to construct images for each of the nouns showed a performance pattern similar to the categorizing group. The results are interpreted in terms of Herriot's (1974) view that different levels of processing are associated with the coding of different clusters of stimulus attributes.  相似文献   
998.
999.
1000.
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