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   59108篇
  免费   2500篇
  国内免费   24篇
  61632篇
  2020年   721篇
  2019年   854篇
  2018年   1213篇
  2017年   1249篇
  2016年   1285篇
  2015年   917篇
  2014年   1107篇
  2013年   5237篇
  2012年   2029篇
  2011年   2039篇
  2010年   1233篇
  2009年   1256篇
  2008年   1796篇
  2007年   1744篇
  2006年   1586篇
  2005年   1334篇
  2004年   1358篇
  2003年   1302篇
  2002年   1237篇
  2001年   1955篇
  2000年   1843篇
  1999年   1385篇
  1998年   668篇
  1997年   564篇
  1996年   640篇
  1995年   588篇
  1994年   577篇
  1993年   550篇
  1992年   1156篇
  1991年   1035篇
  1990年   1028篇
  1989年   991篇
  1988年   974篇
  1987年   891篇
  1986年   898篇
  1985年   944篇
  1984年   783篇
  1983年   665篇
  1979年   797篇
  1978年   610篇
  1976年   519篇
  1975年   652篇
  1974年   725篇
  1973年   752篇
  1972年   636篇
  1971年   598篇
  1970年   520篇
  1968年   644篇
  1967年   556篇
  1966年   527篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
901.
Temporal integration and vibrotactile backward masking   总被引:1,自引:0,他引:1  
Subjects were presented with vibrotactile target patterns to their left index fingertips. The target patterns varied in the number of line segments that they contained and were presented in the presence or absence of a backward-masking stimulus. The stimulus onset asynchrony (SOA) between the target and masker was varied. In an identification task, subjects' errors indicated that the effect of the masker at brief SOAs was to increase the perceived number of line segments in the target. This effect diminished with increasing SOA, and at the longest SOAs subjects confused targets with patterns containing the same number of line segments but varying in how the line segments were related. In an estimation task, the effect of the masker was to increase the number of line segments estimated to be contained in the target pattern. The effect of the masker at brief SOAs is discussed in terms of an integration theory of vibrotactile backward masking. At longer SOAs, the results suggest that the masker may interfere with the extraction of relational information in the target pattern.  相似文献   
902.
A homogeneous sample of normal adults living in a religious order in a study of age effects on reference as a cohesive device in discourse production and comprehension. Narrative and procedural discourse were examined across various levels of complexity and stimulus/response requirements. Results indicate that significant ambiguity of reference emerges in the younger elderly group (age 64-76) in comparison to the middle-aged group (age 27 to 55), and increases markedly in the older elderly group (age 77-92). Related impairments of comprehension and cognition were also observed. These findings are interpreted to be general features of linguistic variation with advancing age. Communicative consequences of ambiguous reference are discussed.  相似文献   
903.
In two sets of experiments we examined pigeons' discrimination performance with a visual flicker-rate continuum, using a conventional successive discrimination procedure. In the first experiment, responses during the intermediate stimulus value were never reinforced, while responses during stimuli on either end of the continuum were reinforced periodically. In the second experiment, responses during stimuli from one end of the continuum were never reinforced, while responses during stimuli from the other end of the continuum were reinforced periodically. Results from both experiments show that discrimination between unchanged positive and negative stimulus values is a function of the range over which the total stimulus set varies. These range effects are comparable to effects found in absolute judgment tasks in human and animal psychophysics. In addition, the range effects reported here are not due to channel capacity, but may depend instead on variability in judgment criteria.  相似文献   
904.
Previous studies have demonstrated the existence of perceptual interactions in the processing of two-word displays such as SAND LANE. When postcued to report one of the two words, subjects often make migration errors, in that the report of the specified word includes a letter of the other word (e.g., LAND or SANE instead of SAND). We find that migrations depend on the abstract, structural similarity of the strings, but not on the physical similarity; on whether the strings are words; and on whether the possible migration responses are words. We also rule out an interpretation of migration errors that attributes them to a guessing strategy. Our findings are interpreted in terms of models in which both strings simultaneously access high-level structural knowledge, that is, knowledge about what sequences of letters fit together to form familiar wholes.  相似文献   
905.
While emotions are usually treated as internal states, it is possible to view them as social relationships. From this perspective, the different emotions are not primarily understood in terms of facial expression, physiological pattern, hedonic tone, or level of arousal, but as different transformations of the relationship between person and other. To demonstrate the value of this approach, judgments of the similarity between different emotions were submitted to multidimensional scaling. It is shown that the resulting dimensions describe different aspects of the relation between self and other. These dimensions provide us with a taxonomy of emotions that makes some important distinctions between closely related emotions and leads to some interesting predictions about personality differences.The authors would like to thank David Stevens for his assistance with the statistical analysis, Eric de Rivera for drafting the three-dimensional figures, and James D. Laird and Shula Sommers for their helpful commentary.  相似文献   
906.
The effects of 6-hydroxydopamine (6-OHDA) injected into the lateral septum in rats were investigated for spontaneous alternation behavior in a Y maze and for spatially oriented behavior in an 8-arm radial maze. The performance of the animals in these tests was assessed under two physiological states, food-satiated and food-deprived. The selective depletion of septal dopaminergic concentrations leads to behavioral disturbances in both the Y and the radial mazes. These deficits disappeared when the animals with 6-OHDA lesions were food-deprived. These results confirm other studies from our laboratory and support two conclusions. First, lesions of dopaminergic neurons lead to behavioral impairments which resemble those found after the total lesion of the structure they innervate. Second, these behavioral impairments are responsive to therapeutic treatments, manipulations of the internal or external environment, or the level of arousal, since under certain conditions a recovery of function can occur in the absence of dopaminergic neurons. These two points provide additional support for a nonspecific role for the dopaminergic neurons originating in the ventral tegmental area. These neurons could have a permissive role in the functioning of the forebrain structures they innervate.  相似文献   
907.
A home centred family therapy approach is described based on the McMaster model. This approach was applied in a controlled trial of three forms of intervention for mother and toddler problems. In this paper the experience of applying the approach is reported.  相似文献   
908.
909.
Although the methodological problems associated with the use of children's self-report depression inventories have previously been discussed in detail, the ethical problems related to the use of these instruments have been largely ignored. The primary purpose of this survey study was to determine how childhood depression researchers have prepared for and responded to children from community (i.e., nonclinic) samples whose nonanonymous scores on self-report depression inventories have indicated that they might be severely depressed or suicidal. Several recommendations, based upon (a) the results of this survey study, (b) the existing literature relevant to the ethical responsibilities of investigators who conduct research with children, and (c) our own experiences with these instruments and populations, are made to assist researchers in their attempts to use these inventories in an ethical manner.The authors would like to thank those childhood depression researchers who were kind enough to return completed surveys.  相似文献   
910.
In an exploration of the social impacts of treatments for hyperactivity, two age groups (kindergarteners and first-graders vs. fourth- and fifth-graders) heard about a hyperactive child whose problem was treated either by an internal and controllable means (effort) or by an external and uncontrollable means (medication) and whose behavior either did or did not improve. The attributions and affective responses of both age groups were influenced by both the nature and the effectiveness of treatment, and there was only weak support for the hypothesis that younger children are more influenced by treatment outcome than older children are. However, older children, conforming to attribution theory predictions, held target children more accountabe for the success or failure of their own efforts than for the outcomes of medication, particularly valuing the child whose own efforts succeeded. By contrast, young children judged the child whose efforts failed as more worthy of pride and more likable than the child whose medication failed. Implications for peer acceptance of hyperactive children over the childhood years are discussed.Portions of this paper were presented at the annual meeting of the Southeastern Psychological Association, Atlanta, March 1985. Thanks are extended to the staff and students of the Model Laboratory School.  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