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   27661篇
  免费   1223篇
  国内免费   9篇
  28893篇
  2020年   324篇
  2019年   329篇
  2018年   486篇
  2017年   494篇
  2016年   543篇
  2015年   412篇
  2014年   529篇
  2013年   2529篇
  2012年   906篇
  2011年   885篇
  2010年   610篇
  2009年   600篇
  2008年   860篇
  2007年   825篇
  2006年   784篇
  2005年   763篇
  2004年   722篇
  2003年   667篇
  2002年   718篇
  2001年   886篇
  2000年   850篇
  1999年   639篇
  1998年   367篇
  1997年   360篇
  1996年   311篇
  1995年   302篇
  1994年   287篇
  1993年   291篇
  1992年   523篇
  1991年   481篇
  1990年   500篇
  1989年   425篇
  1988年   402篇
  1987年   411篇
  1986年   374篇
  1985年   394篇
  1984年   412篇
  1983年   388篇
  1982年   334篇
  1981年   292篇
  1980年   259篇
  1979年   351篇
  1978年   345篇
  1977年   302篇
  1976年   285篇
  1975年   328篇
  1974年   379篇
  1973年   333篇
  1972年   255篇
  1968年   278篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
Short-term memory for 16 monochromatic hues from 425 to 640 nm was measured after six delays from .1 to 24.3 sec by means of an iterative, momentary stimulus-matching technique. Small shifts were revealed in the remembered hue produced by certain wavelengths at some delays. These shifts did not follow trends consistent with a storage dependent on sensory pathway characteristics, perceptually unique hues, or semantic encoding but may reflect entropic effects in a storage that is remarkably unbiased. By indicating the discriminability of hues in memory, standard deviations of the delayed matches reveal other characteristics of what is stored: Their smooth, exponential growth questions the existence of "levels" and permits estimating the half-life of hue memory; their continued resemblance to the discrimination function for simultaneously perceived hues suggests that the stored activity; closely resembled the sensory response of color. The results also indicate how successive comparisons may be corrected in applied color work.  相似文献   
992.
A hierarchical simple structure factor solution was obtained for item scores from a psychometrized battery of Piagetian-type tasks individually administered to 660 kindergarten children. At the first level of factors were the Piagetian theoretical entities of seriation, classification, conservation of number, and temporal and spatial reasoning, with numeration loading on seriation and classification as indicated by the theory. At the second level were two factors identified as Piaget's logicomathematical and infralogical operations. A third-level factor was identified as a g factor. The association of the Piagetian-type tasks with kindergarden and first grade academic achievement was through the third-level g factor. The second-level factors appeared to be similar to Vernon's k:m and v:ed but, like the first level factors, made no important contribution to predicted achievement above that contributed by the g factor. A socioeconomic factor made no unique contribution to predicted first grade achievement. It was concluded that the Piagetian concrete operations variables have no unique role in the prediction of kindergarten or first grade academic achievement.  相似文献   
993.
The present study examined differences in pelvic vasocongestion as a function of negative attitudes toward masturbation. Pelvic vasocongestion was measured thermographically, which is a noninvasive means of detecting and photographing individual heat patterns to indicate physiological condition and functional changes within. The results indicated that women, with positive attitudes toward masturbation, who read an erotic story, experienced the greatest increase in pelvic vasocongestion. This and other findings were discussed in terms of masturbation acting to facilitate the patterning of sexual arousal and orgasmic functioning, especially in regard to creating the capacity for pelvic engorgement.  相似文献   
994.
995.
Current research has suggested that musical stimuli are processed in the right hemisphere except in musicians, in whom there is an increased involvement of the left hemisphere. The present study hypothesized that the more musical training persons receive, the more they will rely on an analytic/left-hemispheric processing strategy. The subjects were 10 faculty and 10 student musicians, and 10 faculty and 10 student nonmusicians. All subjects listened to a series of melodies (some recurring and some not) and excerpts (some actual and some not) in one ear and, after a rest, to a different series of melodies in the other ear. The task was to identify recurring vs. nonrecurring melodies and actual vs. nonactual excerpts. For student musicians, there was a right-ear/left-hemispheric advantage for melody recognition, while for student nonmusicians, the situation was the reverse. Neither faculty group showed any ear preference. There were no significant differences for excerpt recognition. Two possible explanations of the faculty performance were discussed in terms of physical maturation and a functionally more integrated hemispheric approach to the task.  相似文献   
996.
The Social Readjustment Rating Scale (SRRS) was administered to 185 subjects whose age ranged from 21 to 61 yr. The responses were factor analyzed for a principal axis solution followed by isopromax oblique rotation. All the items were loaded and clustered under five factors labeled as follows: (1) personal growth, maturation, and renewal; (2) tension and uncertainty; transitions in personal or occupational situations; (3) changes in one's usual routine and relationship; (4) significant changes in family or mirriage; and (5) personal catastrophies. Males scored significantly higher than females on factors 4 and 5. There were no age differences in the obtained scores. The finding of the factorial structure was thought to add credence to the scale especially in view of past criticism. Implications for future research were also discussed.  相似文献   
997.
The psychometric properties of the Personal Attributes Questionnaire were examined in independent samples of male and female high school students, college students, and adults. In each of the six samples a two-factor structure (masculinity/instrumentality and femininity/expressivity) paralleling the empirically derived scales was found. Additional factor analyses of negative masculine and feminine traits were reported. Discriminant analyses revealed highly significant differentiation between the sexes. The reliabilities (Cronbach alpha) of the unit-weighted scales in each sample were also satisfactory.Support for this research was provided by NASA Grant NSG 2065 (Robert L. Helmreich, Principal Investigator) and NSF Grant BNS 78-08911 (Janet T. Spence and Robert L. Helmreich, Principal Investigators). The article was prepared while the second author was a Fellow at the Center for Advanced Study in the Behavioral Sciences, with support from the Spencer Foundation, NIMH Grant 5T32MH14581-03, and the University of Texas Research Institute.  相似文献   
998.
The perception of the general social standing of husbands and wives in dual-work families as a function of their respective achieved and derived occupational statuses was examined experimentally. The results indicated that both the wife's and husband's general social status was a function only of the husband's occupational status; the wife's occupational status had no effect on either her general social status or that of her husband. The one exception to this was the case of the high achieved occupational status wife depressing the social status of the low occupational status husband. The results are discussed in terms of their implications for recent critiques of male-determined stratification models.  相似文献   
999.
1000.
In this study of psychotic persons in a peasant society, there was a significant attrition in important social network structure after the onset of psychosis. The difficulties involved in providing non-reciprocal social support is noted, yet modest social support of functions may be critical.This work was supported by the National Institute of Mental Health (grant Number 1 R01 MH34322-01). Acknowledgement is expressed to Dr. Phim and Mr. Phimpha for their assistance with data collection, and to Dr. Robert Zimmerman and Ms. Beth Stone for their assistance with data tabulation and analysis.  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