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   26525篇
  免费   974篇
  国内免费   10篇
  2018年   360篇
  2017年   395篇
  2016年   395篇
  2015年   283篇
  2014年   370篇
  2013年   1940篇
  2012年   651篇
  2011年   698篇
  2010年   464篇
  2009年   431篇
  2008年   696篇
  2007年   609篇
  2006年   600篇
  2005年   511篇
  2004年   517篇
  2003年   508篇
  2002年   546篇
  2001年   652篇
  2000年   672篇
  1999年   535篇
  1998年   292篇
  1997年   302篇
  1996年   292篇
  1995年   277篇
  1992年   514篇
  1991年   475篇
  1990年   464篇
  1989年   446篇
  1988年   454篇
  1987年   434篇
  1986年   466篇
  1985年   453篇
  1984年   393篇
  1983年   362篇
  1982年   274篇
  1981年   295篇
  1979年   420篇
  1978年   354篇
  1977年   315篇
  1976年   317篇
  1975年   367篇
  1974年   451篇
  1973年   481篇
  1972年   351篇
  1971年   377篇
  1970年   350篇
  1969年   371篇
  1968年   448篇
  1967年   412篇
  1966年   434篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
201.
Reports that the dihydropyridine Ca2+ channel antagonists may facilitate memory led to the present study of the behavioral effects of nifedipine. Ninety-two 4-day-old male chicks received 0, 100 nM, 100 microM, or 10 mM nifedipine. Drugs were administered in volumes of 2 microliters into the fourth cerebral ventricle 5 min before training on a visual discrimination task. Nifedipine did not produce any detectable changes in behavior during acquisition trials. Retention, however, was impaired 24 h after training in the 100 nM and 100 microM nifedipine-treated chicks, which made significantly more errors than controls. Nifedipine did not affect the amount of time required to complete the task. No effects on body weight gain were detected, suggesting that the memory impairment was not due to a change in feeding behavior. These data are discussed in terms of the role of calcium-dependent processes in memory.  相似文献   
202.
The hypothesis that representation of projective shape is preattentive whereas representation of objective shape in three-dimensional space requires allocation of attention was tested in 2 visual search and 2 precuing experiments. In the visual search experiments, the slope for projective shape search was expected to approach 0 and that for objective shape search was expected to be a positive monotonic function of set size. In the precuing experiments, the effects of precuing were expected to be largely limited to the task requiring representation of objective shape. The overall pattern of results conformed to expectations. The findings are interpreted in the context of a model of shape-at-a-slant processing set out by Epstein and Lovitts (1985) and Epstein and Babler (1989, 1990).  相似文献   
203.
Cerella (1991) has argued that the performance of older adults in the Fisk and Rogers (1991) study is a linear function of the performance of younger adults that is independent of task-specific cognitive requirements. We demonstrate that this is not the case. First, we show that the scatter plot analyses used by Cerella can hide the very task-specific age-related slowing they were designed to reveal. Second, we demonstrate that the percentage of variance explained by such analyses can be misleading. Third, we show that there are reliable differences across tasks in the parameters relating younger and older adults' performance. Finally, we argue that the general, task-independent proportionate slowing that Cerella suggested explains so much of the variance in age-related performance is actually an average slowing that is a function of a relatively small task-independent and a relatively large task-dependent factor.  相似文献   
204.
Little is known about the conditions that encourage animals to learn to use configural associations to guide their behavior or the consequences of such learning for transfer. This study provided some information about these issues by examining how rats solve the transverse-patterning problem, which requires a configural solution (Spence, 1952). Animals had to concurrently solve 3 simultaneous visual discriminations, represented abstractly as A+ versus B-, B+ versus C-, and C+ versus A-. Experiment 1 indicated that rats use a configural solution even when the problems have an elemental solution, provided that the significance of 1 element (e.g., B) shared by 2 problems is ambiguous (e.g., A+/B-; and B+/C-). Experiments 2 and 3 suggested that, when stimulated to use a configural solution by solving the A+/B- and B+/C- problems, rats transfer the configural solution to problems that have no ambiguous elements.  相似文献   
205.
A multivariate hierarchical model of specific cognitive abilities was fitted to data from 7-year-old adopted and nonadopted sibling pairs in the Colorado Adoption Project in order to assess differential genetic influence on specific mental abilities. Model fitting results and Schmid-Leiman (Schmid & Leiman, 1957) transformations reveal significant heritable variation for verbal, spatial, and memory factors independent of general cognitive ability for the eight ability tests examined. In contrast, environmental influences are primarily measure-specific. The results suggest genetic effects in middle childhood that differentially influence mental ability scores.  相似文献   
206.
Although substantial legal difficulties can face anyone trying to recover compensation from counsellors for breach of their legal duties, such claims can in principle succeed. Counsellors ought to take particular care to provide a physically safe setting for the counselling session. Advice given to the client can lead to liability both to the client and to third parties who may be affected. The impact of the client's actions on third parties can justify, and less often compel, departures from confidentiality. The importance of keeping client records has to be balanced against legal obligations imposed on counsellors in various situations to make such records available for inspection by the client or third parties.  相似文献   
207.
A 3×2×2 incomplete factorial design was employed to test the effects of sex, dominance, and their interaction on leader emergence. The factors included dominance distribution (high/high, high/low, middle/middle), sex (male-female), and dyad composition (mixed sex-same sex). The subjects were all Caucasians and were pretested on the California Psychological Inventory Dominance Scale. The data revealed that dominance was a predictor of leader emergence in same-sex conditions where high-dominant individuals assumed the role of leader in much greater proportions than their low-dominant partners. In mixed-sex dyads, sex appeared to be a more potent predictor with males becoming leaders at levels greater than would be suspected given dominance levels.  相似文献   
208.
209.
W. Jay Strickland 《Sex roles》1992,26(9-10):423-439
Unlike other types of career wives, Assemblies of God missionary wives report very high role satisfaction and low depressive symptomatology. In order to explain this “exception,” this study examines (1) the social-structural conditions that affect satisfaction, (2) affective and behavioral responses, and (3) organizational implications. Data were collected through participant observation, interviewing, analysis of documents, and questionnaire research (n=200). Findings suggest that missionary wives often evoked satisfaction in response to institutional emotion norms in the manner suggested by the emotion management perspective. The social-psychological process of emotion work is examined, as well as the manner in which compliance facilitates organizational production and reproduction. Hypotheses for future research are suggested.  相似文献   
210.
This paper addresses some of the dynamics, resistances, and transference and countertransference considerations in group psychotherapy with eating disordered patients. Several resistances are delineated, including guilt over being helped, the recreation of early problems around control and forced feeding, and withdrawal as a defensive operation. A brief vignette is presented which highlights the demand on the part of the therapist as well as the patient to contain and manage feelings rather than acting on them. Lastly, the author argues that group participation helps the patient to identify, articulate, and accept feelings and to promote assertiveness.This paper is based on a presentation given at the Training Institute for Mental Health on May 11, 1991.  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