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   36025篇
  免费   1309篇
  国内免费   11篇
  37345篇
  2018年   544篇
  2017年   493篇
  2016年   575篇
  2015年   414篇
  2014年   497篇
  2013年   3394篇
  2012年   860篇
  2011年   888篇
  2010年   574篇
  2009年   547篇
  2008年   851篇
  2007年   754篇
  2006年   709篇
  2005年   596篇
  2004年   576篇
  2003年   607篇
  2002年   576篇
  2001年   1166篇
  2000年   1122篇
  1999年   856篇
  1996年   488篇
  1995年   466篇
  1994年   458篇
  1993年   429篇
  1992年   897篇
  1991年   797篇
  1990年   800篇
  1989年   702篇
  1988年   709篇
  1987年   689篇
  1986年   690篇
  1985年   673篇
  1984年   598篇
  1983年   495篇
  1982年   389篇
  1981年   406篇
  1980年   380篇
  1979年   565篇
  1978年   425篇
  1976年   383篇
  1975年   525篇
  1974年   515篇
  1973年   581篇
  1972年   556篇
  1971年   496篇
  1970年   439篇
  1969年   422篇
  1968年   532篇
  1967年   453篇
  1966年   440篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
231.
Free-recall and multiple-choice measures of memory for landmarks, sequential order, turns, and route configurations were obtained from younger and older adults after they viewed slides of 2 overlapping routes. Instructions focused attention on either the contents of the slides or on the course of the path; a control condition provided no orientational instructions. Half the subjects viewed maplike diagrams of the joint spatial configuration. Age interacted with instruction only for multiple-choice tests of landmark memory. Age interacted with diagram for each of the other 3 route memory components, although the generality of this interaction across instruction condition depended on whether free-recall or multiple-choice tests were used. The results suggest that route memory may involve both scene and layout representation, which may be differentially sensitive to age and presentational variables.  相似文献   
232.
This study examined whether chronic physical exercise activity is associated with better neurocognitive performance in older adults. One hundred five men participated in 1 of 3 age groups (18-28, 35-45, and 60-73). For each age group, subjects were classified as high or low in fitness on the basis of self-reported activity levels and the results of a submaximal bicycle ergometer test. A comprehensive battery of neuropsychological tests was administered to each subject, and older subjects scored significantly lower than the younger groups on most tests. Significant differences between high- and low-fit subjects were found only on tasks with heavy visuospatial demands, and these differences were most notable in the older adult group. These findings suggest that participation in aerobic exercise activity selectively preserves some cognitive functions that normally decline with age. The benefits of activity appear to be most evident on tasks that require visuospatial processing.  相似文献   
233.
Older adults' life satisfaction can be better understood in light of their personal goals. This study of 179 elders examined (a) how goals correlate with satisfaction, (b) whether elders maintain satisfaction by accommodating goals to past losses, and (c) how correlations between satisfaction and key predictors differ among groups with different goals. Satisfaction was related positively to social maintenance and energetic life-style goals and negatively to concerns for improvement, disengagement, stability, and reduced activity. Past losses were correlated with current goals but not with satisfaction, consistent with the notion of accommodation. A cluster analysis identified 5 patterns of goals: high demand, age prescribed, self-focused, socially engaged, and low demand. Correlations between satisfaction and other predictors differed by cluster, suggesting that the determinants of elders' satisfaction depend on personal goals.  相似文献   
234.
Subjects performed a serial reaction time task (adopted from Nissen & Bullemer, 1987) that contained a repeating pattern of spatial locations. In Experiment 1, following 20 repetitions of a 10- or 16-element pattern, reaction time was equally disrupted for both younger and older people when the sequence became random. In Experiment 2, the response times for subjects encountering the 10-element pattern were compared with those of subjects encountering a random sequence. These response time functions diverged at the same point in training for the 2 age groups. Thus, on this indirect measure of response time facilitation, both experiments revealed age similarity in the rate of pattern learning. In contrast, on a subsequent direct test of pattern learning that required prediction, the younger people earned a higher percentage correct score than the older in both experiments. Age-related dissociations between direct and indirect measures of learning and comparisons with memory-impaired populations are discussed.  相似文献   
235.
Short-term memory for actions was investigated for young adult and elderly adult subjects with the Brown-Peterson procedure at retention intervals of 0 and 15 s. The short-term memory trials were followed by the long-term recall of the prior to-be-remembered actions. The 15-s retention interval was filled either with no activity or with 1 of 3 different interfering activities. Verbal interference had little effect on short-term memory at either age level. Actions performed in the interval either by the subjects or by the experimenter produced significantly lower recall scores at each age level, with the decrement being more pronounced for the elderly than for the young subjects. The long-term memory results indicated that successful short-term recall enhanced later long-term recall, regardless of age level.  相似文献   
236.
The dimensions by which adults of differing ages experience emotion were studied by self-administering questionnaires administered to older adults (n = 828) recruited from Elderhostel programs, middle-aged (ages 30-59) children of Elderhostel attenders (n = 231), and young adult (ages 18-29) subjects recruited from college classes or through Elderhostel participants (n = 207). Elders were higher in emotional control, mood stability, and emotional maturity through moderation and leveling of positive affect and lower in surgency, psychophysiological responsiveness, and sensation seeking. These findings are consistent with the hypothesized increase in self-regulatory capacity with age. These cross-sectional differences cannot, however, be distinguished from cohort-related explanations; they require considerable replication across different types of subjects and further characterization of the dimensions in terms of their functions for self-regulation.  相似文献   
237.
Recent research on individual psychological assessments for personnel decision-making purposes has indicated a great deal of variability in practice. This study compared the responses of psychologists who evaluated the same set of assessment protocols on the basis of graduate training and professional affiliation. Results indicated few differences in evaluations of those assessed or in the way assessments were conducted. Concerns about training for and the practice of individual assessment are discussed.  相似文献   
238.
The purpose of this pilot study was to assess the effectiveness of a brief test user orientation program on increasing service station managers' familiarity with a few key employment testing issues, including their familiarity with theModel Guidelines for Preemployment Integrity Testing Programs. The obtained results reveal that even a brief orientation program was able to significantly increase the managers' stated degree of familiarity with testing issues.  相似文献   
239.
The present research examined whether line-ups based on target (‘suspect’) face similarity are biased or suggestive. Four experiments are described in which subjects constructed photographic line-ups by selecting foils similar in appearance to a target. Later, another group of subjects who had not seen the faces before (mock witnesses) were asked to pick out the targets from the line-ups. All four experiments showed that mock witnesses selected the target significantly more often than expected by chance, thereby demonstrating suggestiveness. Three alternative line-up construction methods were also evaluated. In these methods, foil selection was based not only on target similarity but also on similarity with one or more of the other line-up faces. Results showed that alternative line-up targets were not selected significantly more often than chance, suggesting that bias was reduced. An overall analysis showed that the alternative line-ups were significantly less suggestive than target-based line-ups. The results indicate that foil selection procedures that incorporate foil-to-foil similarity produce fairer line-ups than those exclusively based on target similarity.  相似文献   
240.
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