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81.
Examined postpartum effects of a school-based intervention program for pregnant adolescents. Interviews were conducted with 102 innercity black, low-income, school-aged mothers who had attended the program, and their academic and medical records were reviewed. For teenagers who had been poor students prior to becoming pregnant, a strong linear effect was found for duration of program attendance: with sufficient time in the program, poorer students became indistinguishable from better students in educational success. Most of the better students were educationally successful at 2 years postpartum, independent of their length of time in the program. For all students, longer durations of postnatal intervention were predictive of lower likelihood of subsequent childbearing. Numerous academic, medical, social, and demographic variables were ruled out as possible confounding factors that might have produced the positive educational outcomes for poorer students. The results suggest that adolescents who appear to have minimal academic promise prior to their pregnancy are nevertheless very responsive to school-based intervention.  相似文献   
82.
Taking the integrated viewpoints of causal theory of reference, cognitive science and the notion of correspondence principles from physics, this paper addresses the problems of creativity, the nature of visual imagery and the manner in which science progresses.  相似文献   
83.
This piece sets the scene for the inaugural addresses by Rosi Braidotti and Selma Sevenhuijsen which follow and provides background information on the history of women's studies in the Netherlands.  相似文献   
84.
Our original goal was to explore the nature of the grouping-by-movement phenomenon reported by Driver and Baylis (1989). In their studies, distractors that moved in common with a centrally located target had a larger influence on focused-attention performance than did more proximate but stationary distractors. These results seemed particularly important since they suggested, contrary to the predictions of space-based models of attention, that attention could be allocated to noncontiguous regions of the visual field. Their results also suggested mandatory processing of stimuli with common motion. Unfortunately, we were unable to replicate this grouping-by-movement effect. In the conditions of Experiment 1 in which we replicated Driver and Baylis’s methodology, stationary distractors produced a larger response-compatibility effect than did the more distant distractors that moved in common with the target. In Experiment 2, we redundantly coded the centrally located target and the far distractors with common movement and color. However, the results were identical to those obtained in Experiment J. The stationary near distractors that appeared in a different color from the target and the far distractors produced the largest response-compatibility effect. In a final experiment, we attempted to compensate for the reduced acuity of the moving distractors by adjusting their size by a cortical magnification factor. However, even with this manipulation, we found a larger response-compatibility effect for the stationary near distractors than for the moving distant distractors. Our results suggest that subjects are capable of selectively processing a target item that moves in common with distractors.  相似文献   
85.
Three experiments were conducted to test for the presence of associations between contextual cues and the nominal conditioned stimulus (CS) in fear conditioning. Rats were given tone-footshock pairings and were tested for their fear of the nominal CS, the tone, in a different context. Experiments 1 and 2 demonstrated that rats given nonreinforced exposure to the training context following conditioning were less fearful of the CS. Experiment 3 indicated that additional footshock presentations in the training context following conditioning produced greater fear of the CS. In both procedures postconditioning treatments designed to directly alter only the associative strength of the training context yielded parallel changes in the conditioned response to the CS. These data suggest that within-compound associations are formed between the context and the CS during classical conditioning.  相似文献   
86.
Most adults of average and superior intelligence incorrectly assume that in a two dimensional figure two attributes, area, and perimeter, are locked in a fixed relationship such that if one remains unchanged so does the other. Consequently, when they correctly conserve one attribute during shape transformation, they incorrectly conserve the other. Mentally retarded individuals assume no such fixed relationship but depend exclusively on perceptual information. Although this dependence adversely effects their judgment of conservation, it allows them to correctly judge the changed state of the nonconserved attribute.  相似文献   
87.
In two 6-month longitudinal studies of intellectually advanced preschool children, letter naming time and backward digit span were moderately good predictors of concurrent reading achievement (PIAT Reading Recognition Score). None of the remaining measures in a battery of standard cognitive indices, including Stanford-Binet MA, was associated with reading achievement. The results of cross-lagged correlation analysis of data from one of the two samples suggested that individual differences in time to access name codes for visual stimuli predict, but are not a consequence of, individual differences in reading achievement. The results of the cross-lagged analysis for the second sample were inconclusive. As a whole, the results are consistent with findings from other populations indicating that both short term memory span and efficiency of retrieval from long term memory are related to reading ability. The results also indicate, however, that the relationship between retrieval efficiency and reading achievement in precocious readers cannot be described by extrapolation of threshold estimates from the performance of older, unselected groups of readers.  相似文献   
88.
89.
Previous research has shown substantial improvements in detection performance when subjects consistently detect a subset of stimuli. In contrast, in conditions in which stimuli appear as both targets and distractors, there is little performance improvement with practice. The present experiments examine how varying degrees of consistency determine the improvement of detection accuracy with extended practice. The degree of consistency was varied by manipulating the frequency with which a letter was a distractor while holding the number of occurrences as a target constant. The experiments utilized a multiple-frame target-detection search paradigm in which subjects were to detect single-letter targets in a series of rapidly presented letters on four channels. Experiments showed that detection performance improvement with practice was a monotonic function of the degree of consistency, decreasing to zero as the target-to-distractor ratio increased from 10:0 to 10:20. As consistency decreased, detection performance asymptoted earlier and at a lower level. A dual-task experiment examined subjects’ ability to perform the previously trained search task as a secondary task. Results showed that the previous targetto-distractor consistency had a marked effect on resource sensitivity of the detection task. The general issues of consistency in the development of skilled performance and in the development of automatic processing are discussed.  相似文献   
90.
Three studies were conducted to test whether imagery accounts for the effects of empathy on attributions, that is, whether attributers construct and scan a mental image of social scenarios the same way that actual participants scan a real environment. According to this interpretation, attributers “see” the world as the participant does and make vicarious attributions. An alternative interpretation holds that subjects base vicarious attributions on recreating the motivations and affect of the actor, so that imaging is irrelevant to empathy and attributions. In the first study, subjects who imagined a story from the perspective of a particular character later showed differential recall of story details as a function of role, but not differential attributions. In Experiment 2, role-taking subjects showed clear effects of imaged perspective on recall for story details, but no effects on attributions of causality for an accident. Further, recall and attribution were uncorrelated. In the last study, empathy and imagery role-taking instructions produced independent effects: imagers showed pronounced perspective-relevant recall and empathizers did not. Neither showed unambiguous vicarious attributions. Recall and attribution were again uncorrelated. These studies suggest that the imagery explanation of empathy effects is untenable, and imply that the recall of perspective-relevant details is unlikely to mediate attributions of causality in imaginary scenarios.  相似文献   
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