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   65515篇
  免费   2601篇
  国内免费   31篇
  2020年   627篇
  2019年   786篇
  2018年   1067篇
  2017年   1132篇
  2016年   1159篇
  2015年   872篇
  2014年   989篇
  2013年   4741篇
  2012年   1841篇
  2011年   1916篇
  2010年   1234篇
  2009年   1189篇
  2008年   1731篇
  2007年   1648篇
  2006年   1477篇
  2005年   1341篇
  2004年   1249篇
  2003年   1236篇
  2002年   1196篇
  2001年   2193篇
  2000年   2129篇
  1999年   1562篇
  1998年   712篇
  1997年   603篇
  1992年   1426篇
  1991年   1344篇
  1990年   1345篇
  1989年   1187篇
  1988年   1174篇
  1987年   1146篇
  1986年   1137篇
  1985年   1256篇
  1984年   1003篇
  1983年   855篇
  1982年   629篇
  1981年   613篇
  1979年   1060篇
  1978年   721篇
  1977年   698篇
  1976年   656篇
  1975年   930篇
  1974年   1000篇
  1973年   1091篇
  1972年   921篇
  1971年   828篇
  1970年   822篇
  1969年   827篇
  1968年   1061篇
  1967年   928篇
  1966年   904篇
排序方式: 共有10000条查询结果,搜索用时 125 毫秒
221.
Depression and mental control: the resurgence of unwanted negative thoughts   总被引:6,自引:0,他引:6  
In three experiments we examined depressed individuals' mental control abilities and strategies. Experiment 1 revealed that although depressed college students were initially successful in suppressing negative material, they eventually experienced a resurgence of unwanted negative thoughts. Analysis of subjects' stream-of-consciousness reports indicated that this resurgence was associated with the use of negative thoughts as distracters from the unwanted item. In Experiment 2 depressed subjects acknowledged that positive distracters were more effective than negative ones in suppressing negative thoughts. This acknowledgement suggests that depressed subjects in Experiment 1 did not deliberately focus on negative distracters but that those thoughts automatically occurred because they were highly accessible. Experiment 3 demonstrated that depressed subjects' use of positive distracters could be increased somewhat when we provided such distracters and made them easily accessible. Taken together, the findings suggest that depression involves an enhanced accessibility of interconnected negative thoughts that can undermine mental control efforts.  相似文献   
222.
223.
Noting the pervasiveness of videogames in American culture, the authors set out to examine the effects that playing videogames has on children. Thirty-one children were matched on sex, randomly assigned to play either a violent (karate) videogame or a nonviolent (jungle vine swinging) videogame, and then observed during free play. The main results were that the children who had played the jungle swing videogame later played more with a jungle swing toy and that the children who played the violent videogame later showed more aggression. The authors interpreted the findings as an indication that young children who play videogames later tend to act similarly to how their videogame character acted.  相似文献   
224.
Subjects (N= 28) performing a complex disjunctive concept-formation task on a microcomputer were given the opportunity to seek help following failure to correctly identify concepts. The proportion of those seeking help was significantly greater when the source of help was the computer itself (86%) rather than another person (36%). Consistent with past research, those who did not ask for help gave reasons other than the potential negative social consequences of doing so. Self-report data and a systematic test for the presence of experimenter-induced demand ruled out several possible sources of confounding. The results have implications for designers of time-sharing and networked computer systems.  相似文献   
225.
The relative importance of genetic and environmental factors for neuroticism, extraversion, impulsivity, and monotony avoidance were estimated in a sample of 99 monozygotic and 229 dizygotic pairs of twins reared apart (TRA) and a matched sample of 160 monozygotic and 212 dizygotic pairs of twins reared together (TRT). The average age was 58.6 (SD = 13.6); 72% of the twins were 50 or older. Model-fitting analyses verified the importance of genetic factors for all four measures; from 23% to 45% of the total variation was attributable to genetic sources. There was considerable evidence that these factors were operating in a nonadditive manner for extraversion and impulsivity. Shared environment accounted for less than 10% of the variance; some evidence for selective placement was found for neuroticism.  相似文献   
226.
Traits and states are concepts that people use to both describe and understand themselves and others. We show that people view these concepts as prototype-based categories that have a graded internal structure and fuzzy boundaries and identify a set of attributes that define the prototypical cores of two categories: traits and states. Prototypical traits are stable, long-lasting, and internally caused. Prototypical states are temporary, brief, and caused by external circumstances. These prototypes are not defined by averages, as the family-resemblance principle would suggest, but by ideal (or extreme) attribute values. Like other ideal-based categories, traits and states serve particular goals. Trait concepts permit people to predict the present from the past; state concepts identify those behaviors that can be controlled by manipulating the situation. These two complementary schemas are part of the extensive theory of psychological causality that is implicit in language. Abstract social concepts differ from object categories in their category standards, the nature of their attributes, and the interrelations among those attributes.  相似文献   
227.
Previous longitudinal studies of personality in adulthood have been limited in the range of traits examined, have chiefly made use of self-reports, and have frequently included only men. In this study, self-reports (N = 983) and spouse ratings (N = 167) were gathered on the NEO Personality Inventory (Costa & McCrae, 1985b), which measures all five of the major dimensions of normal personality. Cross-sectional and longitudinal analyses on data from men and women aged 21 to 96 years showed evidence of small declines in Activity, Positive Emotions, and openness to Actions that might be attributed to maturation, but none of these effects was replicated in sequential analyses. The 20 other scales examined showed no consistent pattern of maturational effects. In contrast, retest stability was quite high for all five dimensions in self-reports and for the three dimensions measured at both times in spouse ratings. Comparable levels of stability were seen for men and women and for younger and older subjects. The data support the position that personality is stable after age 30.  相似文献   
228.
The present study is concerned with the perceptual information about the body and space underlying the act of catching a ball. In a series of four experiments, subjects were asked to catch a luminous ball under various visual conditions. In general, catching in a normally illuminated room was contrasted with catching the luminous ball in an otherwise completely dark room. In the third and fourth experiments, intermediate conditions of visual information were included. The results suggest that it is possible to catch a ball with one hand when only the ball is visible, but performance is better when the subject has the benefit of a rich visual environment and two hands. The second experiment indicated that subject performance does improve with practice in the dark, but time spent in the darkened room itself doesn't result in a significant decrement in performance. Results of the third study suggest that vision of one's hand does not aid in the performance of this task whereas the presence of a minimal visual frame appears to aid performance. The final study examined the relation between catching performance and body sway under similar visual conditions. Results of this experiment imply that persons who exhibit relatively little postural sway in full-room lighting performed better at this catching task.  相似文献   
229.
Previous research has demonstrated that mild negative emotional imagery and unpleasant sensory stimuli lead to greater electromyographic activity over the brow muscle region than mild positive imagery and stimuli, even in the absence of significant changes in visceral and general facial EMG activity. Previous research has not addressed whether electromyographic responses over the brow region are a sensitive and specific index of emotions, however, since a multiplicity of events lead to changes in brow activity. In this research, facial electromyographic and audiovisual recordings were obtained while individuals were interviewed about themselves. Afterwards, individuals were asked to describe what they had been thinking of during specific segments of the interview marked by distinctive electromyographic responses over the brow region in the context of ongoing but stable levels of activity elsewhere in the face. The results are interpreted in terms of a continuous flow hypothesis of affect-laden information processing.  相似文献   
230.
Social contagion of binge eating   总被引:6,自引:0,他引:6  
A social psychological account of the acquisition of binge eating, analogous to the classic social psychological work, "Social Pressures in Informal Groups" (Festinger, Schachter, & Back, 1950), is suggested and tested in two college sororities. In these sororities, clear evidence of group norms about appropriate binge-eating behavior was found; in one sorority, the more one binged, the more popular one was. In the other, popularity was associated with binging the right amount: Those who binged too much or too little were less popular than those who binged at the mean. Evidence of social pressures to binge eat were found as well. By the end of the academic year, a sorority member's binge eating could be predicted from the binge-eating level of her friends (average r = .31). As friendship groups grew more cohesive, a sorority member's binge eating grew more and more like that of her friends (average r = .35). The parsimony of a social psychological account of the acquisition of binge eating behavior is shown. I argue that there is no great mystery to how bulimia has become such a serious problem for today's women. Binge eating seems to be an acquired pattern of behavior, perhaps through modeling, and appears to be learned much like any other set of behaviors. Like other behaviors, it is under substantial social control.  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