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   32407篇
  免费   448篇
  国内免费   1篇
  2020年   168篇
  2019年   206篇
  2018年   3705篇
  2017年   3072篇
  2016年   2533篇
  2015年   407篇
  2014年   339篇
  2013年   1275篇
  2012年   1000篇
  2011年   2782篇
  2010年   2772篇
  2009年   1762篇
  2008年   2086篇
  2007年   2532篇
  2006年   385篇
  2005年   545篇
  2004年   497篇
  2003年   406篇
  2002年   400篇
  2001年   265篇
  2000年   243篇
  1999年   219篇
  1998年   189篇
  1997年   174篇
  1996年   157篇
  1995年   160篇
  1994年   139篇
  1993年   145篇
  1992年   164篇
  1991年   168篇
  1990年   155篇
  1989年   137篇
  1988年   130篇
  1987年   122篇
  1986年   119篇
  1985年   144篇
  1984年   162篇
  1983年   165篇
  1982年   165篇
  1981年   180篇
  1980年   137篇
  1979年   176篇
  1978年   180篇
  1977年   168篇
  1976年   146篇
  1975年   167篇
  1974年   164篇
  1973年   121篇
  1972年   112篇
  1967年   97篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
The study examined physical symptoms and health service utilization of subjects high or low on a measure of the tendency to experience stress somatically and high or low on a measure of current stress. High somatic responders reported greater numbers of symptoms than low somatic responders regardless of stress level. However, high somatic responders who were experiencing high levels of current stress reported significantly more symptoms than high somatic responders who were experiencing low levels of stress. These findings indicate that somatic response to stress reflects both a general tendency to focus on physical symptoms, and a specific tendency to focus more on physical symptoms when under stress. Analysis of health service records indicated that high somatic responders had more visits prompted by symptoms than low somatic responders, but did not differ in frequency of health service visits designed to maintain health. The findings further clarify the relationship between somatic response to stress, physical symptoms and health service use.  相似文献   
43.
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   
44.
This study investigated the effect of television food commercials on children's self-control within a resistance to temptation paradigm. Commercial type, food stimulus type, and the child's sex provided the three independent variables in a 4 × 4 × 2 factorial design. Behavioral and self-report indices of temptation and control were measured. Children were significantly more tempted to transgress for the low-nutrition food, regardless of the commercial shown. Sex differences in reported degree of temptation were found. However, the television commercials did not affect the children's latency to transgress.  相似文献   
45.
46.
47.
The social support patterns of a sample of 101 suicide attempters were compared with the patterns of a control sample on the basis of structured interview data. Network characteristics and the extent of support in different functional categories were examined as to their absolute and relative power to discriminate between the suicide attempters and the controls. A clear separation of the functions of kin and of friends/acquaintances emerged. The crucial difference between the attempters and the controls lay in the number of friends with whom the subjects had agreeable everyday interactions and in the number of kin that provided crisis support, both psychological and instrumental. Other support differences between the two groups were of secondary importance. While there was no overall difference in the frequency of social interactions between the two groups, the size of the social network differed greatly. Consequences for the conceptualization and measurement of social support as well as for the prevention of suicidal behavior are discussed.  相似文献   
48.
Day and Bellezza (1983) rejected a dual coding imagery explanation for the superior recall of concrete words because unrelated concrete pairs were rated lower in composite imagery but were still remembered better than related abstract pairs. We show that dual coding theory explains their results and our new findings using the same paradigm. In Experiment 1, 120 subjects rated imagery or relatedness for 108 pairs that varied in concreteness, pair relatedness, and associative strength. Incidental cued recall followed. Relatedness and strength affected imagery ratings, as did concreteness, and very low relatedness partly accounted for the low composite imagery ratings for unrelated concrete pairs. Concreteness and relatedness also affected recall, and suporior recall for unrelated concrete pairs occurred consistently under imagery but not under relatedness instructions. In Experiment 2, 40 subjects rated imagery value and recalled 24 pairs. Subsequent questioning indicated that composite images were retrieved better given stimuli from unrelated concrete than from related abstract pairs. These findings and Day and Bellezza’s original results are explained in terms of (1) imaginal and verbal associative processes, which jointly influence composite imagery ratings and recall, and (2) the critical role of stimulus concreteness during image retrieval and recall (i.e., the conceptual peg hypothesis).  相似文献   
49.
Short-term memory for Chinese characters and radicals   总被引:1,自引:0,他引:1  
Short-term memory for Chinese radicals and characters, varying in orthographic complexity, frequency, and—for radicals—intercharacter frequency (the number of compound characters that contain the radical), was studied using an immediate free-recall task. When radicals or characters are relatively frequent, so that their pronunciations are well known by literate Chinese, they seem to be maintained in verbal form in short-term memory. For these stimuli, intercharacter frequency and complexity have relatively small influences on memory span. Stimuli low in frequency, with pronunciations that are not apt to be known, seem to be maintained in visual form in short-term memory. Memory span is much smaller for these stimuli and is influenced by both intercharacter frequency and complexity. Furthermore, short-term memory for relatively high-frequency characters is interfered with more by a verbal than by a visual intervening task, whereas the opposite is true for low-frequency characters.  相似文献   
50.
The possibility that rats can navigate in the Morris water maze by reducing the difference between the memorized platform scene and the current sensory input was tested in nine blind rats. A computerized videosystem monitored the rats' movements in the pool and converted the rat-target distance into tones the frequency of which increased in 64 equal steps from 120 Hz at 128 cm to 7680 Hz at 0 cm. During 15 days of training to find a fixed platform position from different starting points (12 trials per day) average escape latencies decreased from 39.0 to 25.4 s. The performance significantly deteriorated when the acoustic distance signalization was omitted and/or when the target position was changed form trial to trial. It is concluded that blind rats solved the task by simultaneously employing search strategy based on position responses, mapping using acoustic background beacons, and distance reduction navigation. It is argued that the various strategies are additive and that their relative significance depends of the conditions of the experiment.  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