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   173216篇
  免费   7751篇
  国内免费   157篇
  2020年   2822篇
  2019年   3476篇
  2018年   3496篇
  2017年   3934篇
  2016年   4654篇
  2015年   3967篇
  2014年   4826篇
  2013年   23579篇
  2012年   4535篇
  2011年   3630篇
  2010年   3877篇
  2009年   4822篇
  2008年   3832篇
  2007年   3380篇
  2006年   3969篇
  2005年   3981篇
  2004年   3511篇
  2003年   3153篇
  2002年   2937篇
  2001年   3107篇
  2000年   2938篇
  1999年   2992篇
  1998年   2837篇
  1997年   2671篇
  1996年   2583篇
  1995年   2409篇
  1994年   2382篇
  1993年   2327篇
  1992年   2515篇
  1991年   2366篇
  1990年   2214篇
  1989年   2158篇
  1988年   2099篇
  1987年   2171篇
  1986年   2157篇
  1985年   2393篇
  1984年   2503篇
  1983年   2275篇
  1982年   2366篇
  1981年   2342篇
  1980年   2162篇
  1979年   2187篇
  1978年   2156篇
  1977年   2148篇
  1976年   1925篇
  1975年   2009篇
  1974年   2056篇
  1973年   1957篇
  1972年   1551篇
  1971年   1513篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
The purpose of the present study was to determine if there were differences in hemispheric lateralization during the experience of emotions and if those differences were related to personality style. College-age adult subjects selected for high positive and negative affectivity on Tellegen's Multidimensional Personality Questionnaire (MPQ; Tellegen, 1982) viewed video stimuli selected for their emotionally evocative nature and rated the intensity of the emotions they experienced. The ongoing electroencephalogram (EEG) was recorded while they watched the video clips. Analyses of the EEG data revealed that there were differences in regional activation during the emotional video clips, especially for those stimuli selected to elicit either happy or disgust emotions. These results support the hypothesis that the right hemisphere is specialized for the experience of certain negative affects, whereas the left hemisphere is specialized for the experience of certain positive affects. The findings also indicated some support for the theory that individual differences in personality style are related to differing levels of hemispheric arousal.  相似文献   
972.
To examine the relative contribution of fluency and recollection to the word completion performance of amnesics, we administered a task in which patients were told specifically not to utilize previously presented words during stem completion (an Exclusion condition). This condition was contrasted with a standard word completion task in which patients were encouraged simply to complete the stem with the first word that came to mind (an Inclusion condition). Since the exclusion condition necessitated controlled respecification of the initial presentation, it was hypothesized that amnesics would be less able than controls to exclude study list items. Consistent with this hypothesis, the results indicated that the amnesics' performance, unlike that of the alcoholic controls, did not significantly differ as a function of task condition. To examine whether amnesics' conscious recollection could be enhanced, Experiment 2 presented the study list five times. The amnesics now were able to exclude a significant number of items from the study list; however, they still did so considerably less frequently than alcoholic controls. For the alcoholic controls, increasing the number of study trials had little additional effect on their exclusion performance, but it significantly enhanced their inclusion performance. Taken together, these findings suggest that for control subjects, word completion performance is likely mediated by a combination of fluency and recollection, while for amnesic patients, performance is almost exclusively based on the fluency with which an item comes to mind.  相似文献   
973.
In a group of male and female subjects we studied the VEPs related to the solution of a lexical decision task presented in the Left and Right Hemispaces with respect to the Central position in order to explore the electrophysiological correlates of the performance asymmetries obtained when overt spatial attention is directed to the Left or Right Hemispace. When stimuli were presented in the Left Hemispace a significant asymmetry was observed between the two hemispheres of the negative activity around 280 msec in the occipital-parietal areas. Moreover a general increase in the Central and Frontal areas of both the hemispheres was observed. In this paper we discuss why these effects can be considered to be the cause of the costs on accuracy observed in the male subjects. The differences obtained with the female group are discussed in relation to the observed modification on the negative activity around 400 msec with stimuli in the Left Hemispace. These findings give some suggestions about the interaction of structural and attentional mechanisms in the brain during the solution of a lateralized cognitive task.  相似文献   
974.
The current study investigates sources of between-subjects variation in asymmetry scores on visual half-field and dichotic listening tasks. For each of these presentation modalities, subjects were given multiple laterality tasks. Results indicate that about 50% of the between-subjects variations in asymmetry scores in each modality is attributable to individual differences in perceptual asymmetries that are not stimulus-specific, referred to as "characteristic perceptual asymmetries" in this paper. In addition, the question of whether individual differences in characteristic perceptual asymmetries are modality specific, modality general, or both was investigated by entering subjects' asymmetry scores from visual half-field and dichotic listening tasks into a principal component analysis. The results of this analysis indicate that there are both modality specific and modality general influences on subjects' characteristic perceptual asymmetries.  相似文献   
975.
Ss tend to remember close-up photographs as having had extended boundaries (Intraub & Richardson, 1989). Three alternate explanations were tested: object completion, distortion toward a perceptual schema, and normalization toward a prototypic view. In three experiments, 55-130 undergraduates viewed 16 close-up, prototypic, or wide-angle views of objects for 15 s each. Immediately or 48 hr later, they rated test pictures on a 5-point scale as "same", "closer up", or "father away." Results ruled out object completion because boundary extension occurred when the picture contained no incomplete objects. Immediate tests supported the perceptual schema hypothesis because all unidirectional distortions involved boundary extension. Delayed tests were more suggestive of a memory schema effect because wide-angle pictures yielded boundary restriction. A two-component model of picture processing is proposed.  相似文献   
976.
977.
978.
Studies of time estimation have provided evidence that human time perception is determined by an internal clock containing a temporal oscillator and have also provided estimates of the frequency of this oscillator (Treisman, Faulkner, Naish, & Brogan, 1992; Treisman & Brogan, 1992). These estimates were based on the observation that when the intervals to be estimated are accompanied by auditory clicks that recur at certain critical rates, perturbations in time estimation occur. To test the hypothesis that the mechanisms that underlie the perception of time and those that control the timing of motor performance are similar, analogous experiments were performed on motor timing, with the object of seeing whether evidence for a clock would be obtained and if so whether its properties resemble those of the time perception clock. The prediction was made that perturbations in motor timing would be seen at the same or similar critical auditory click rates. The experiments examined choice reaction time and typing. The results support the hypothesis that a temporal oscillator paces motor performance and that this oscillator is similar to the oscillator underlying time perception. They also provide an estimate of the characteristic frequency of the oscillator.  相似文献   
979.
This article describes a study conducted to identify the range of potential influences that a computer-assisted careers guidance system (PROSPECT (HE)) had on the functioning of organisations (careers services in higher education). Data from six institutions indicated that use of PROSPECT (HE) was associated with important and varied change within the organisations. It appears that when a careers service seeks opportunities for change, CACG systems can be an important catalyst for change in two respects: by providing a focal point for achieving previously established goals; or, as a consequence of system use, by making staff aware of the potential for new organisational goals.  相似文献   
980.
Gender differences in children's play activities, preferred school subjects, and occupational goals were examined in relation to such parental variables as toy-giving and chore assignment. Subjects were 245 children in grades K, 3, 6, and 8. Subjects completed questionnaires before and after Christmas asking what gifts they wanted, asked for, received, and liked best. They also were asked to name their friends and play activities, favorite and least-liked school subjects, occupational aspirations, and chores at home. Children generally wanted, asked for, received, and most-liked gender-typical toys. They were less likely to receive requested gender-atypical toys. Children's preferred activities, job aspirations and assigned chores were along gender-typical lines. Girls preferred masculine toys and jobs more than boys preferred feminine ones. With increasing age, both girls and boys increasingly preferred masculine toys and male friends. No gender differences in favorite or least-liked school subjects were found. School subject preference was related to gender-typing of occupational choice for girls but not boys.An earlier version of this paper was presented at the annual meeting of the American Psychological Association, Anaheim, California, 1983.  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