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   169305篇
  免费   7675篇
  国内免费   157篇
  177137篇
  2021年   1479篇
  2020年   2762篇
  2019年   3422篇
  2018年   3431篇
  2017年   3866篇
  2016年   4547篇
  2015年   3899篇
  2014年   4775篇
  2013年   23359篇
  2012年   4324篇
  2011年   3342篇
  2010年   3797篇
  2009年   4708篇
  2008年   3664篇
  2007年   3158篇
  2006年   3841篇
  2005年   3832篇
  2004年   3334篇
  2003年   3019篇
  2002年   2788篇
  2001年   2965篇
  2000年   2864篇
  1999年   2959篇
  1998年   2791篇
  1997年   2643篇
  1996年   2575篇
  1995年   2396篇
  1994年   2367篇
  1993年   2316篇
  1992年   2492篇
  1991年   2332篇
  1990年   2202篇
  1989年   2138篇
  1988年   2126篇
  1987年   2139篇
  1986年   2124篇
  1985年   2325篇
  1984年   2491篇
  1983年   2266篇
  1982年   2364篇
  1981年   2322篇
  1980年   2166篇
  1979年   2147篇
  1978年   2149篇
  1977年   2118篇
  1976年   1929篇
  1975年   1960篇
  1974年   2051篇
  1973年   1929篇
  1972年   1489篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
881.
This article provides a comprehensive review of the research on smoking and body weight. The relationships between smoking and body weight are evaluated in 70 cross-sectional and longitudinal investigations. The mechanisms responsible for differences in body weight are discussed, the weight-related issues that promote smoking behavior are reviewed, methods for reducing postcessation weight gain are summarized, and future research directions are proposed. A proposed working research model for studying the relationship between smoking, energy balance, and weight gain is offered. It is concluded that smoking and body weight relationships are closely related and pose significant challenges for smoking researchers.  相似文献   
882.
The Psychological Record - The present experiments investigated blocking effects in rhesus monkeys (Macaca mulatta) in a discrimination learning paradigm using a single stimulus modality. Two...  相似文献   
883.
Reviews     
  相似文献   
884.
Four experiments were conducted to test earlier claims about the relationship between the negative afterimage and the McCollough effect. The first claim (Hansel & Mahmud, 1978) is that long-lasting afterimages occur when induced by the same alternating-stimulus procedure as that used to induce the McCollough effect. The second claim (Murch & Hirsch, 1972) is that afterimages can themselves induce McCollough effects if they are induced and paired sequentially with grating patterns. In testing these claims, a reliable computer-controlled color-cancellation technique developed earlier was used to measure the apparent color of both afterimages and McCollough effects objectively. No support was found for the first claim following alternative presentation of two homogeneously colored regions for total periods of 5 min (Experiment 1) and 20 min (Experiment 2). The second claim was fully supported: After an induction period of 7.3 min, a McCollough effect occurred for a red-vertical pairing but not for a green-horizontal pairing (Experiment 3); but after an induction period of 20 min, McCollough effects occurred strongly for both pairings (Experiment 4). The theoretical implications of these outcomes are considered in the context of recent theories of color and pattern processing in the visual system.  相似文献   
885.
In this article, the experience of conversion, which is usually delegated to the realm of spiritual studies, is applied to the counseling experience. It is posited that a person who goes through a successful counseling process will experience a turning around, will cease leading life in a dysfunctional way, and will move forward in a manner by which the person experiences life in a new perspective. This new perspective brings the person wholeness and balance.  相似文献   
886.
The 16th century schism in Christian thought leading to the Reformation has an interesting analogy in Carl Rogers' attempt to reform the helping professions. An exploration of this analogy clarifies much of the theoretical tension in the contemporary arena of pastoral counseling.  相似文献   
887.
The purpose of the present study was to develop an easily administered scale to assess adolescents' perceptions of both their own social competence and social participation in relationships. Six items were used to generate two factors that accounted for about 68% of the variance.  相似文献   
888.
Instructional and probability manipulations of bias in multiletter matching   总被引:1,自引:0,他引:1  
Ratcliff (1985) performed fits of his diffusion model to the results of multiletter-matching experiments conducted by Ratcliff and Hacker (1981) and Proctor, Rao, and Hurst (1984), in which bias to respond "same" or "different" was manipulated by instructions and probabilities, respectively. The fits showed that both bias manipulations affected settings of a goodness-of-match criterion, whereas instructions also affected sensitivity. Evaluations of the experimental procedures and of Ratcliff's model-fitting procedures were performed in the present study. Three experiments showed that instructions and probabilities had similar effects, regardless of whether the different pairs were blocked or randomized according to the number of mismatching positions. The most salient feature of the results--that "same" reaction times were traded off more than were "different" reaction times, with no corresponding asymmetry in the error rates--was evident in all situations. The evaluation of Ratcliff's model-fitting procedures indicated that the apparent influence of instructions on sensitivity likely is an artifact of unequal variance for the sets of same and different pairs. Moreover, the effects of bias can be explained in terms of settings of response criteria, rather than of the goodness-of-match criterion, as in Ratcliff's fits.  相似文献   
889.
Obstacle perception by congenitally blind children   总被引:1,自引:0,他引:1  
The ability to perceive objects from a distance and navigate without vision depends principally on auditory information. Two experiments were conducted in order to assess this ability in congenitally blind children aged 4 to 12 years who had negligible amounts of visual experience or formal mobility training. In Experiment 1, children walked along a sidewalk toward a target location to get some candy. A box was placed along the path on some trials, and the children were instructed to avoid the box if it was present. The children spent more time in the region just in front of the box than in the region just behind it, indicating that they perceived the box and acted so as to navigate around it. In Experiment 2, children attempted to discriminate whether a nearby disk was on their left or on their right. The children performed at above-chance levels, again indicating distal perception of objects. The results of both experiments suggest that blind children with little or no visual experience or formal training utilize nonvisual information, presumably auditory, to perceive objects. The specific nature of this auditory information requires further investigation, but these findings imply that the underlying perceptual ability does not require experience in spatial vision or deliberate training and intervention.  相似文献   
890.
Semantic congruity effects in perceptual comparisons   总被引:1,自引:0,他引:1  
Semantic congruity effects occur when, as in Experiment 1, for example, the time to select the shorter of two relatively short lines is faster than the time to select the longer; conversely, selection of the longer of two relatively long lines is faster than selection of the shorter. Semantic congruity effects are also demonstrated in experiments requiring comparisons of the heaviness of weights (Experiment 2) and horizontal extent (Experiment 3). In Experiment 1, the magnitude of the semantic congruity effect was larger under conditions emphasizing accuracy rather than speed and when the comparison was difficult. In fact, when comparisons were errorless, the effect was minimal (20 msec), thereby replicating previous failures to obtain the effect with supraliminal perceptual comparisons (Banks, Mermelstein, & Yu, 1982; Marschark & Paivio, 1981; Petrusic & Baranski, 1988a). In confirmation of Henmon's (1911) introspective analyses of psychophysical comparisons, Experiments 2 and 3 extend the range of the semantic congruity effect to include judgments of confidence. However, in each of the three experiments, semantic congruity effects were not evident with the response-accuracy measure. Finally, using highly confusable stimuli, in Experiment 3 the magnitude of the semantic congruity effect was shown to be larger for error than for correct response times. The implications of these findings for a decisional locus of the effect and for the semantic coding theory are discussed.  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