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841.
The report from President George W. Bush’s New Freedom Commission on Mental Health (NFC), Achieving the Promise: Transforming Mental Health Care in America(2003), proposes goals and recommendations for improving mental health services. This report has significant implications for the delivery of mental health services through the schools. A focused discussion of the potential opportunities and challenges of implementing NFC recommendations related to school-based mental health is presented. Strategies for addressing five key areas at the intersection of school mental health and the Commission’s recommendations include: stigma reduction, suicide prevention, expansion and improvement of school mental health, and screening and treatment of co-occurring mental health and substance abuse disorders.  相似文献   
842.
Making sense of the visual world requires keeping track of objects as the same persisting individuals over time and occlusion. Here we implement a new paradigm using 10-month-old infants to explore the processes and representations that support this ability in two ways. First, we demonstrate that persisting object representations can be maintained over brief interruptions from additional independent events - just as a memory of a traffic scene may be maintained through a brief glance in the rearview mirror. Second, we demonstrate that this ability is nevertheless subject to an object-based limit: if an interrupting event involves enough objects (carefully controlling for overall salience), then it will impair the maintenance of other persisting object representations even though it is an independent event. These experiments demonstrate how object representations can be studied via their 'interruptibility', and the results are consistent with the idea that infants' persisting object representations are constructed and maintained by capacity-limited mid-level 'object-files'.  相似文献   
843.
Thirty-one 8- and 9-year-old children selected for dyscalculia, reading difficulties or both, were compared to controls on a range of basic number processing tasks. Children with dyscalculia only had impaired performance on the tasks despite high-average performance on tests of IQ, vocabulary and working memory tasks. Children with reading disability were mildly impaired only on tasks that involved articulation, while children with both disorders showed a pattern of numerical disability similar to that of the dyscalculic group, with no special features consequent on their reading or language deficits. We conclude that dyscalculia is the result of specific disabilities in basic numerical processing, rather than the consequence of deficits in other cognitive abilities.  相似文献   
844.
To study sources of individual differences in pubertal development, the authors fit a sex-limitation common factor model to data reported, at ages 11 and 14 years, by 1,891 twin pairs on items that comprise the Pubertal Development Scale (PDS; A. C. Petersen, L. Crockett, M. Richards, & A. Boxer, 1988). The model divides variation into a general pubertal factor and item-specific variation and, in addition, decomposes it into constituent sources. In both boys and girls, genetic influences made the largest contribution to variance common to PDS items. Genetic and nonshared environmental factors accounted for variation specific to PDS items in boys, whereas for girls, common environmental influences were added for growth spurt and menarcheal status. For both common and item-specific variation, genetic effects were partially sex specific. Subsidiary analyses found accelerated maturation in both boys and girls who at age 14 were reared in father-absent homes.  相似文献   
845.
This study evaluated behavioral skills training (BST), in a multiple baseline across subjects design, for teaching firearm safety skills to 6 6- and 7-year-old children. Similar to previous research with 4- and 5-year-olds, half of the children acquired the safety skills following BST and half acquired the skills following BST plus in situ training.  相似文献   
846.
This article describes the development and validation of a biographical data (biodata) measure and situational judgment inventory (SJI) as useful predictors of broadly defined college student performance outcomes. These measures provided incremental validity when considered in combination with standardized college-entrance tests (i.e., SAT/ACT) and a measure of Big Five personality constructs. Racial subgroup mean differences were much smaller on the biodata and SJI measures than on the standardized tests and college grade point average. Female students tended to outperform male students on most predictors and outcomes with the exception of the SAT/ACT. The biodata and SJI measures show promise for student development contexts and for selecting students on a wide range of outcomes with reduced adverse impact.  相似文献   
847.
The present studies assessed the effect of behavioral inhibition on interactions of college students in mixed-sex groups. In Study 1, 20 participants were arranged into two dyadic groups based on self-rated measures of approach/withdrawal behavior. These dyads (inhibited men/uninhibited women; inhibited women/uninhibited men) were videotaped during an unstructured 5-min. interaction in a laboratory. Time series analysis indicated greater behavioral covariation in the inhibited men/uninhibited women dyads and less behavioral covariation in the inhibited women/uninhibited men dyads. Additional analyses indicated a relationship between inhibition and comfort experienced during the interaction. Inhibited participants, particularly women, reported feeling uncomfortable while interacting with an uninhibited male partner. A second study corroborated the findings reported in Study 1 and also noted elevated heart rate in the inhibited women. This increased discomfort in women appeared to be related to heightened self-consciousness during the interaction.  相似文献   
848.
The authors sought to measure a component of the avoidance self-regulation system, specifically one related to object appraisal functions. Participants performed a choice reaction time task (Studies 1 & 2) or a go/no go task (Study 3) in which they were asked to categorize words (e.g., knife) as threatening in nature. In a series of three studies involving 236 undergraduates, the authors found that introverts who were skilled at categorizing events as threatening (vs. introverts slow to do so) experienced more negative affect in their daily lives. Among extraverts, threat categorization performance did not predict negative affect. The authors suggest that implicit threat categorizations render individuals vulnerable to negative affect but that high levels of Extraversion are capable of inhibiting such affective consequences. The authors discuss implications of the findings for extant views of Extraversion, avoidance motivation, and self-regulation.  相似文献   
849.
We studied the choice behavior of 2 monkeys in a discrete-trial task with reinforcement contingencies similar to those Herrnstein (1961) used when he described the matching law. In each session, the monkeys experienced blocks of discrete trials at different relative-reinforcer frequencies or magnitudes with unsignalled transitions between the blocks. Steady-state data following adjustment to each transition were well characterized by the generalized matching law; response ratios undermatched reinforcer frequency ratios but matched reinforcer magnitude ratios. We modelled response-by-response behavior with linear models that used past reinforcers as well as past choices to predict the monkeys' choices on each trial. We found that more recently obtained reinforcers more strongly influenced choice behavior. Perhaps surprisingly, we also found that the monkeys' actions were influenced by the pattern of their own past choices. It was necessary to incorporate both past reinforcers and past choices in order to accurately capture steady-state behavior as well as the fluctuations during block transitions and the response-by-response patterns of behavior. Our results suggest that simple reinforcement learning models must account for the effects of past choices to accurately characterize behavior in this task, and that models with these properties provide a conceptual tool for studying how both past reinforcers and past choices are integrated by the neural systems that generate behavior.  相似文献   
850.
Roberts B  Harris MG  Yates TA 《Perception》2005,34(7):847-856
Although the Ebbinghaus illusion is commonly used as an example of a simple size-contrast effect, previous studies have emphasised its complexity by identifying many factors that potentially influence the magnitude of the illusion. Here, in a series of three experiments, we attempt to simplify this complexity. In each trial, subjects saw a display comprising, on one side, a target stimulus surrounded by inducers and, on the other, an isolated probe stimulus. Their task was to indicate whether the probe appeared larger or smaller than the target. Probe size was adjusted with a one-up, one-down staircase procedure to find the point of subjective equality between probe and target. From these experiments, we argue that the apparent effects of inducer size are often confounded by the relative completeness of the inducing surround and that factors such as the similarity of the inducers and target are secondary. We suggest a simple model that can explain most of the data in terms of just two primary and independent factors: the relative size of the inducers and target, and the distance between the inducers and the target. The balance between these two factors determines whether the size of the target is underestimated or overestimated.  相似文献   
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