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   23113篇
  免费   1123篇
  国内免费   16篇
  24252篇
  2023年   159篇
  2021年   249篇
  2020年   359篇
  2019年   438篇
  2018年   596篇
  2017年   600篇
  2016年   649篇
  2015年   479篇
  2014年   513篇
  2013年   2047篇
  2012年   920篇
  2011年   1020篇
  2010年   581篇
  2009年   559篇
  2008年   774篇
  2007年   708篇
  2006年   603篇
  2005年   549篇
  2004年   551篇
  2003年   536篇
  2002年   484篇
  2001年   809篇
  2000年   818篇
  1999年   547篇
  1998年   243篇
  1997年   224篇
  1996年   181篇
  1995年   174篇
  1993年   172篇
  1992年   413篇
  1991年   370篇
  1990年   415篇
  1989年   392篇
  1988年   378篇
  1987年   323篇
  1986年   357篇
  1985年   342篇
  1984年   274篇
  1983年   236篇
  1979年   216篇
  1978年   186篇
  1975年   196篇
  1974年   255篇
  1973年   208篇
  1972年   218篇
  1971年   178篇
  1969年   202篇
  1968年   212篇
  1967年   172篇
  1966年   192篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
When given a choice between two mashes of equal caloric density but differing flavors, rats (Rattus norvegicus) show a robust preference for the flavor previously associated with a higher calorie food. This finding suggests that rats may identify food quality by sensory cues such as taste. Our initial attempt to show this effect in the golden Syrian hamster (Mesocricetus auratus) failed, apparently because of this species's tendency to store both high- and low-calorie mashes in their cheek pouches during conditioning trials. Initially we attempted to circumvent this seeming morphological constraint on learning by presenting low- and high-calorie mashes on alternate days. This procedure too failed to produce evidence of flavor-caloric learning, although this procedure produced robust learning in another rodent, the Mongolian gerbil (Meriones unguiculatus). Another method of preventing cheek pouching--concurrently presenting low- and high-calorie liquid diets--was more successful; then, hamsters showed clear evidence of flavor-caloric learning. Thus, although flavor-caloric learning is demonstrable in species of rodent besides the rat, the circumstances under which it occurs vary.  相似文献   
62.
It is proposed that expert knowledge can operate as a cognitive cueing structure for the acquisition and retention of new information in memory. Two experiments are reported which demonstrate that expert knowledge about football and clothing can act as mnemonic cues for the recall of information newly associated with that knowledge. In Experiment 1 expert terms from the domains of football and clothing and those neutral nouns paired with them were both better recalled by experts than by non-experts. In Experiment 2 passages containing information contrary to factual knowledge about football and clothing were recalled better by experts than by non-experts, in spite of the fact that information in the passages contradicted what the experts already knew. The results of the two experiments were interpreted as showing that expert knowledge provides mental cues that have desirable mnemonic properties such as constructibility, associability, discriminability and invertibility. Also, the interpretation of expert knowledge as a cognitive cueing structure is compared to Ausubel's ideas regarding advance organizers.  相似文献   
63.
In this study, the relations among depression, anxiety, and neuroticism measured by self-report questionnaires were investigated. Subjects were 207 psychiatric patients. High correlations were found among self-report scales purporting to measure depression, anxiety, and neuroticism. Results of a content analysis showed considerable overlap among these scales. A division of items into six content categories did not result in lower correlations compared to the original scales.  相似文献   
64.
Seventh-grade students and teachers from twenty-three middle and junior high schools were surveyed to determine the association between teacher attitudes, behavioral intentions, and smoking behavior and the prevalence of student smoking. Teacher attitudes toward smoking policies were found to be strongly related to the current smoking behavior of the teacher but not consistently related to student smoking. In addition, teacher likelihood of intervening showed a modest association with teacher smoking status, with current smokers generally indicating being the least likely to intervene for student possession or use of cigarettes. Teacher intentions to intervene were strongly associated with the prevalence of smoking among boys but not girls.  相似文献   
65.
D Mates  K R Allison 《Adolescence》1992,27(106):461-474
A series of focus group interviews was used to identify major sources of stress and coping responses of Grade 10 students. Relationships with parents and family, work, and lack of money were found to be important sources of stress. Major coping responses included substance use and diversionary activities. Differences between academic streams (tracks) in sources of stress and coping responses were examined.  相似文献   
66.
To study malevolent representations, earliest memories were reliably coded on scales of affect tone. Ss were diagnosed with borderline personality disorder: 31 without and 30 with concurrent major depression. Nonborderline comparison subjects had either major depressive disorder (n = 26) or no psychiatric diagnosis (n = 30). Borderline subjects were discriminated from comparison subjects by their more malevolent representations; they more frequently produced memories involving deliberate injury; and they portrayed potential helpers as less helpful. Results suggest the diagnostic significance of malevolent representations, which need to be explained by any theory of borderline personality disorder.  相似文献   
67.
This research evaluated the relationship between pain and sleep problems, and the role of pain and sleep problems in depression, in a sample of 242 patients who had been diagnosed with definite or classical rheumatoid arthritis (RA). Patients completed the Pain scale of the Arthritis Impact Measurement Scales, the Center for Epidemiological Studies Depression Scale, and self-reports of sleep disturbance at two data waves over a 2-year interval. Cross-sectional multiple regression analysis revealed that the sleep problems variable was independently associated with depression at Time 1. Longitudinal multiple regression analyses demonstrated that prior pain predicted subsequent adverse changes in sleep problems, whereas sleep problems did not affect pain over time, and prior pain and the interaction of high pain and high sleep problems were independently associated with depression from Time 1 to Time 2. These data suggest that pain may exacerbate sleeping difficulty in RA patients, and that both factors may contribute to depression over time.  相似文献   
68.
Employers of human resource professionals described their hiring practices. This information is especially useful for counselors and for developing curricula for nonbusiness majors interested in human resource careers.  相似文献   
69.
To integrate the 5-dimensional simple-structure and circumplex models of personality, the Abridged Big Five Dimensional Circumplex (AB5C) taxonomy of personality traits was developed, consisting of the 10 circumplexes that can be formed by pitting each of the Big Five factors against one another. The model maps facets of the Big Five dimensions as blends of 2 factors. An application to data consisting of 636 self-ratings and peer ratings on 540 personality trait adjectives yielded 34 well-defined facets out of a possible 45. The AB5C solution is compared with simple-structure and lower dimensional circumplex solutions, and its integrative and corrective potential are discussed, as well as its limitations.  相似文献   
70.
A survey of 821 same-sex female twin pairs from a population-based registry assessed 8 dimensions of social support and social integration. Twin analyses documented significant common environmental influences on 5 of these 8 measures and significant genetic influences on 5 of the 8. A decomposition of the multiplicative association between support and a measure of stressful life experiences in predicting depressed mood--an association typically interpreted as providing evidence for a stress-buffering effect of social support--shows clearly that it is the environmental and genetic factors that cause support, rather than support itself, that buffer the effects of stress on mood in most cases. We discuss the implications of this result for future research on the relationship between social support and psychopathology.  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