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61.
In two experiments, we assessed the ability of a feedback stimulus during helplessness training to reduce the performance deficits common to inescapable shock. In each experiment, four groups of rats were exposed to either escapable shock (E), inescapable shock with a feedback stimulus following shock termination (Y-FS), inescapable shock with no feedback stimulus (Y-NFS), or no shock (N). The feedback stimulus eliminated the interference effects of inescapable shock when tested with an FR-3 lever press escape task (Experiment 1) or on an FR-1 task with a 3-s delay between the response and shock termination (Experiment 2). These results suggest that stress-induced biochemical changes may mediate the interference effects seen in inescapably shocked rats.  相似文献   
62.
Finke and Pinker (1982, 1983) showed subjects an array of dots followed by an arrow in a blank field, and asked them to determine whether the arrow pointed to any of the previously seen dots. Response times were linearly related to the distance between the arrow and the nearest dot, suggesting that subjects spontaneously used an internal scanning or extrapolation process to perform the task. We replicate and extend this finding by varying the retention interval, and by employing a paradigm in which subjects’ eyes are closed and the arrows are described to them using a coordinate scheme. We also show that subjects are unable to predict the form of the data when the task simply is described to them. Results suggest that mental scanning along a straight path can be performed on images reconstructed from memory, and that it does not depend on the ongoing perception of a continuous surface, on physical eye movements, or on demand characteristics.  相似文献   
63.
Civic actions are behaviours intended to improve conditions for others or help shape a community's future. Such actions vary widely from voting to voluntary helping, from canvassing to community organizing, and attempts have been made to categorize the array of civic actions. However, the question of why young adults engage in some types of civic actions versus others is not well understood. Using data from 598 White, cisgender, heterosexual young adults in the United States, we examined the relations between individual civic efficacy, collective civic efficacy, and seven actions: writing social media posts, voting, buycotting, volunteering, participating in an organization, supporting political candidates, and protesting. We hypothesized that individual efficacy would be positively related to all seven actions, but collective efficacy would be more strongly related to collective or political actions, compared to the individual or civil ones. Logistic regression analyses showed that individual efficacy positively predicted engagement in all seven civic actions. Individual and collective efficacy had a complex curvilinear relation with buycotting and supporting political candidates. Implications for future research and applications aimed at promoting civic engagement amongst young adults are discussed. Please refer to the Supplementary Material section to find this article's Community and Social Impact Statement .  相似文献   
64.
A computational short cut suggested by Feldman and Klinger for the one-sided Fisher-Yates exact test is clarified and is extended to the calculation of probability values for certain two-sided tests when sample sizes are unequal.  相似文献   
65.
The Rockefeller University, New York, New York 10021 Events such as barpresses or licks, which may occur at any time during the day, are often clustered into bouts. The internal structure of such bouts can be recorded using an AM tape recorder, running the tape recorder only while bouts are in progress, and can later be analyzed off-line on a digital computer.  相似文献   
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Ronald N. Giere 《Synthese》1969,20(3):371-387
A comparison of Neyman's theory of interval estimation with the corresponding subjective Bayesian theory of credible intervals shows that the Bayesian approach to the estimation of statistical parameters allows experimental procedures which, from the orthodox objective viewpoint, are clearly biased and clearly inadmissible. This demonstrated methodological difference focuses attention on the key difference in the two general theories, namely, that the orthodox theory is supposed to provide a known average frequency of successful estimates, whereas the Bayesian account provides only a coherent ordering of degrees of belief and a subsequent maximization of subjective expected utilities. To rebut the charge of allowing biased procedures, the Bayesian must attack the foundations of orthodox, objectivist methods. Two apparently popular avenues of attack are briefly considered and found wanting. The first is that orthodox methods fail to apply to the single case. The second is that orthodox methods are subject to a typical Humean regress. The conclusion is that orthodox objectivist methods remain viable in the face of the subjective Bayesian alternative — at least with respect to the problem of statistical estimation.  相似文献   
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69.
Speed of sorting decks of 32 cards with two alternative stimuli was measured. The stimuli were pairs of dots with attributes of distance between dots, angle of orientation of the pair, and position of the pair to the right or left of center. The attributes varied in relative discriminability and were used in all possible pair- and triple-correlated (redundant) combinations. Results showed an increase in speed of sorting with either an increase in discriminability or an increase in number of redundant attributes. It is argued that the increased speed with addition of redundant attributes is due both to a selective serial processing of attributes (requiring attribute separability) and to an increased discriminability with combined attributes (requiring attribute integrality).  相似文献   
70.
Services of rehabilitation agencies and facilities tend to be structured to the needs of the larger American culture. It is important, however, to reconsider our social service programs in view of the needs of different cultural groups when providing services that will aid these individuals to move across cultural boundaries. An attempt is made in this paper to develop a model of the individual who undergoes such cultural transition. Such a model should help define problems in service programs, assess the value of current service activities, and identify areas for developing new services that will aid the overall process of cultural transition. A model of behavior development is outlined, followed by a formulation of a model of the individual in cultural change.  相似文献   
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