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921.
The present study focuses on the potential use of factor analytic techniques for the identification of personality dimensions in young children. Earlier work in this area has tended to rely on rating scales which predetermined the outcome of the analyses by their built-in theoretical biases. The scales here were designed to reflect a child's total area of functioning and to require the least amount of inference on the part of the rater. Three studies were done with a total of 129 nursery and kindergarten children. Of the factors identified, three were reproduced consistently in each of the studies. Factor I, Social Confidence, is characterized by leadership and assertiveness in interpersonal relations. Factor II, Cooperation, suggests a passivity in interpersonal relations and somewhat of a dependent stance. Factor III, Persistence, reflects a potential for problem solving and task orientation. It seems to have some relationship, as well, to autonomy. Two additional factors which appear rather consistently are Mobility and Aggression The factors which appeared here are compared with findings from earlier work and suggest the possibility of deriving factor scores for separate children for comparative and developmental study.  相似文献   
922.
Context effects have been shown to bias lay people's evaluations of the severity of crimes and punishments. To investigate the cognitive mechanisms behind these effects, we develop and apply a rank-based social norms approach to judgments of perceived crime seriousness and sentence appropriateness. In Study 1, we find that (a) people believe on average that 84% of people illegally download software more than they do themselves and (b) their judged severity of, and concern about, their own illegal software downloading is predicted not by its amount but by how this amount is believed (typically inaccurately) to rank within a social comparison distribution. Studies 2 and 3 find that the judged appropriateness of a given sentence length is highly dependent on the length of other sentences available in the decision-making context: The same objective sentence was judged as approximately four times stricter when it was the second longest sentence being considered than when it was the fifth longest. It is concluded that the same mechanisms that are used to judge the magnitude of psychophysical stimuli bias judgments about legal matters.  相似文献   
923.
924.
The neural correlates of working memory (WM) in schizophrenia (SZ) have been extensively studied using the multisite fMRI data acquired by the Functional Biomedical Informatics Research Network (fBIRN) consortium. Although univariate and multivariate analysis methods have been variously employed to localize brain responses under differing task conditions, important hypotheses regarding the representation of mental processes in the spatio-temporal patterns of neural recruitment and the differential organization of these mental processes in patients versus controls have not been addressed in this context. This paper uses a multivariate state-space model (SSM) to analyze the differential representation and organization of mental processes of controls and patients performing the Sternberg Item Recognition Paradigm (SIRP) WM task. The SSM is able to not only predict the mental state of the subject from the data, but also yield estimates of the spatial distribution and temporal ordering of neural activity, along with estimates of the hemodynamic response. The dynamical Bayesian modeling approach used in this study was able to find significant differences between the predictability and organization of the working memory processes of SZ patients versus healthy subjects. Prediction of some stimulus types from imaging data in the SZ group was significantly lower than controls, reflecting a greater level of disorganization/heterogeneity of their mental processes. Moreover, the changes in accuracy of predicting the mental state of the subject with respect to parametric modulations, such as memory load and task duration, may have important implications on the neurocognitive models for WM processes in both SZ and healthy adults. Additionally, the SSM was used to compare the spatio-temporal patterns of mental activity across subjects, in a holistic fashion and to derive a low-dimensional representation space for the SIRP task, in which subjects were found to cluster according to their diagnosis.  相似文献   
925.
In functional magnetic resonance imaging (fMRI), the blood oxygenation level dependent (BOLD) signal is often interpreted as a measure of neural activity. However, because the BOLD signal reflects the complex interplay of neural, vascular, and metabolic processes, such an interpretation is not always valid. There is growing evidence that changes in the baseline neurovascular state can result in significant modulations of the BOLD signal that are independent of changes in neural activity. This paper introduces some of the normalization and calibration methods that have been proposed for making the BOLD signal a more accurate reflection of underlying brain activity for human fMRI studies.  相似文献   
926.
The present study assesses the relationship between religious faith, worship discourse, and military policy attitudes among White Americans. Our work suggests that religious congregations are important spaces for Whites to potentially engage in dissenting political talk. We find that the degree to which congregations inform military policy attitudes, laity must be involved in political discussions. However, this study also suggests that religious faith plays a role in the degree to which political discussions had within worship spaces associates with anti-war attitudes. White Evangelical Protestants tend to be less opposed to aggressive military policy than others. These differences become particularly pronounced among Evangelical and Mainline Protestants as members of these religious faiths become involved in and/or exposed to social-political discussions within worship spaces.  相似文献   
927.
Attributes of words can be known even when the words are not currently retrievable. Although repeatedly demonstrated for semantic and contextual dimensions, the evidence is ambiguous for structural characteristics. The present research demonstrates significant above-chance first-letter knowledge across four ordinal levels of retrieval confidence for nonretrieved words—tip of the tongue (TOT), high familiar, low familiar, unfamiliar. Contrary to prior research, there was minimal evidence for syllable number knowledge, even at highest confidence levels. Initial letter recognition in the absence of retrieval resembles the recognition without identification in episodic memory (Cleary, Current Directions in Psychological Science 17: 353–357, 2008), and such implicit familiarity may contribute more generally to confidence assessments of word knowledge in both semantic and episodic memory domains. Furthermore, this outcome suggests that word feature priming in the form of partial phonological activation may occur to some extent for all words during a retrieval attempt, and even for ones that are judged to be unknown.  相似文献   
928.
929.
Mood management studies typically have found that adults will select media that enhance positive moods and reduce negative moods. In this study, adolescents diagnosed with major depressive disorder and control adolescents without psychiatric disorders were called on customized cell phones up to 4 times a day and asked about their current mood state and media use for five extended weekends across an 8-week period. Mood effects on subsequent media use, mood during media consumption, and media effects on subsequent mood were examined. Results indicated that adolescents who consumed fun media tended to do so in a way that sustained, rather than enhanced their prior positive mood levels during and after consumption-if they turned to media. Adolescents in more negative moods did not often use media to improve their moods. When they did, boys were more likely than girls to use media that ultimately reduced negative mood levels. Findings are discussed in light of the literature on mood management, adolescence, and depression.  相似文献   
930.
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