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911.
Previous social dilemma research has shown that sanctioning defection may enhance cooperation. The authors argue that this finding may have resulted from restricting participants to two behaviors (cooperation and defection). In this article, the authors introduce the concept of a "social trilemma" (a social dilemma in which an alternative option to defect is present) and tested the effect of a sanction. The authors show that a sanction only increased cooperation and collective interests in the traditional social dilemma. In a social trilemma, the sanction failed because it caused some people to choose the alternative option to defect. Moreover, the results indicate that this was especially the case when people did not expect fellow group members to cooperate. In this case, the sanction even worked counterproductive because it decreased collective interests. It is concluded that allowing individuals to consider alternative options to defect can reveal the potential detrimental effects of sanctioning systems for the collective.  相似文献   
912.
Pitch and time are two principal form-bearing dimensions in Western tonal music. Research on melody perception has shown that listeners develop expectations about "What" note is coming next and "When" in time it will occur. Our study used sequences of chords (i.e., simultaneously sounding notes) to investigate the influence of these expectations on chord processing (Experiments 1 and 4) and subjective judgments of completion (Experiments 2 and 3). Both tasks showed an influence of tonal relations and temporal regularities: expected events occurring at the expected moment were processed faster and led to higher completion judgments. However, pitch and time dimensions interacted only for completion judgments. The present outcome suggests that for chord perception the influence of pitch and time might depend on the required processing: with a more global judgment favoring interactive influences in contrast to a task focusing on local chord processing.  相似文献   
913.
This article reports on a series of 5 analyses of spontaneous production of verbal inflection (tense and person–number agreement) by 2-year-olds acquiring French as a native language. A formal analysis of the qualitative and quantitative results is developed using the unique resources of Optimality Theory (OT; Prince & Smolensky, 2004). It is argued that acquisition of morphosyntax proceeds via overlapping grammars (rather than through abrupt changes), which OT formalizes in terms of partial rather than total constraint rankings. Initially, economy of structure constraints take priority over faithfulness constraints that demand faithful expression of a speaker's intent, resulting in child production of tense that is comparable in level to that of child-directed speech. Using the independent Predominant Length of Utterance measure of syntactic development proposed in Vainikka, Legendre, and Todorova (1999), production of agreement is shown first to lag behind tense then to compete with tense at an intermediate stage of development. As the child's development progresses, faithfulness constraints become more dominant, and the overall production of tense and agreement becomes adult-like.  相似文献   
914.
What information is used for sorting pictures of complex stimuli into categories? We applied a reverse correlation method to reveal the visual features mediating categorization in humans and baboons. Two baboons and 6 humans were trained to sort, by species, pictures of human and baboon faces on which random visual noise was superimposed. On ambiguous probe trials, a human-baboon morph was presented, eliciting "human" responses on some trials and "baboon" responses on others. The difference between the noise patterns that induced the two responses made explicit the information mediating the classification. Unlike the humans, the baboons based their categorization on information that closely matched that used by a theoretical observer responding solely on the basis of the pixel similarities between the probe and training images. We show that the classification-image technique and principal components analysis provide a method to make explicit the differences in the information mediating categorization in humans and animals.  相似文献   
915.
Recent studies have shown that emotionally significant stimuli are often better identified than neutral stimuli. It is not clear, however, whether these results are due to enhanced perceptual processing or to a bias favoring the identification of emotionally significant stimuli over neutral stimuli. The present study used a two-alternative forced-choice perceptual identification task to disentangle the effects of bias and enhanced processing. We found that emotionally significant targets were better identified than neutral targets. In contrast, the emotional significance of the foil alternative had no effect on performance. The present results support the hypothesis that perceptual encoding of emotionally significant stimuli is enhanced.  相似文献   
916.
A 90 degrees rotation of a display can turn a relatively easy visual search into a more difficult one. A series of experiments examined the possible causes of this effect, including differences in overall item shape and response mapping (Experiment 1), the interpretation of scene lighting (Experiment 2), the axis of internal symmetry of the search items (Experiment 3), and the axes of interitem symmetry between target and distractor items (Experiment 4). Only the elimination of differences in interitem mirror symmetry resulted in equal search efficiency in the upright and rotated displays. This finding is strong support for the view that visual search is guided by an analysis that considers interitem relations.  相似文献   
917.
The objective of this study was to provide new primary data on Rorschach Comprehensive System stability levels. To achieve this, we tested 75 French nonpatient adults twice on the Rorschach with a 3-month interval between the tests. Interrater reliability was in the excellent range for most of the variables studied. The overall stability level in a selected set of previously studied variables was below expectations (median r = .53). Personality, cognitive or self/relational variables yielded higher test-retest correlations than emotional and coping variables. Moderators of stability could be identified: (a) overall level of Task Engagement (TE) in F, m, FM + m, a, FC, Sum C', Sum V, Sum Shd, Fr + rF, INC + FAB, COP, es, Adj es, EGO, and Blends; (b) variations in TE in F, FM, and p; (c) state distress in Zd, m, FM + m, a, C, CF + C, WSumC, FD, and es; (d) variables derived from the number of responses impacted stability in P, Zf, m, FC, CF + C, Sum C', Sum V, MOR, EA, es, and Blends. These results provide further support for the reliability of several measures. Examiner effects as an influence on productivity and TE were identified as an important area for future research.  相似文献   
918.
This study examined a potential confound in the inverse relationship between target duration and saccadic latency reported by Adam, Ketelaars, Kingma, and Hoek in 1993. Eight participants located a briefly flashed target by moving the eyes and the cursor toward its position in a (backward) mask condition and in a no-mask condition. Analysis showed similar saccadic latencies in both conditions, thereby refuting the potentially confounding role of the backward masking procedure. It is tenatively suggested that the longer saccadic latencies noted for shorter target durations may be associated with delayed accumulation of evidence for the detection of the target.  相似文献   
919.
In the present study brain laterality, hemispheric communication, and mental rotation performance were examined. A sample of 33 women were tested for a possible linear relationship of testosterone level and mental rotation with structural background of the brain. Subjects with a smaller splenial area of corpus callosum tended to have lower levels of testosterone (r =.37, p<.05). However, there were no significant differences in mean scores of mental rotation of object and hand between groups with high and low levels of testosterone. There was a significant difference in relative size of the 6th area (slice) of the corpus callosum between groups with good and poor scores on mental rotation of an object and also in relative size of the 4th and 5th slices of the corpus callosum between groups on mental rotation of the hand. The good and poor scorers' show different relations with the measures of the corpus. The mental rotation of hand was associated with the parietal areas of the corpus callosum, while the mental rotation of object was associated only with the occipital area. These observations suggest that higher testosterone levels may be associated with a larger splenial area, which represents an important connection between the parieto-occipitocortical areas involved in activation of mental images. Further srudy is encouraged.  相似文献   
920.
The aim of this study was to examine the reliability and factor structure of the Finnish version of the Sport Imagery Questionnaire, a measure which examines cognitive and motivational functions of imagery. The final sample comprised 231 participants drawn from 34 sports and ranging in age from 14 to 49 years (M = 20.9, SD = 5.8). Internal consistency and confirmatory factor analyses were undertaken to evaluate the reliability and factorial validity of the scale. Fit indices and modification data generated from examining the 30-item five-factor model were equivocal, suggesting minor amendment and recategorization of several items rather than major adjustment to the proposed latent factor structure. Cronbach coefficients alpha indicated the scale is reliable. Overall, these results provide positive additional support for the claim that the Sport Imagery Questionnaire has a reproducible factor structure and is a reliable test for measuring imagery use in Finnish athletes.  相似文献   
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