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951.
Numbers are fundamental entities in mathematics, but their cognitive bases are unclear. Abundant research points to linear space as a natural grounding for number representation. But, is number representation fundamentally spatial? We disentangle number representation from standard number-to-line reporting methods, and compare numerical estimations in educated participants using line-reporting with three nonspatial reporting conditions (squeezing, bell-striking, and vocalizing). All three cases of nonspatial-reporting consistently reproduced well-established results obtained with number-line methods. Furthermore, unlike line-reporting—and congruent with the psychophysical Weber–Fechner law—nonspatial reporting systematically produced logarithmic mappings for all nonsymbolic stimuli. Strikingly, linear mappings were obtained exclusively in conditions with culturally mediated elements (e.g., words). These results suggest that number representation is not fundamentally spatial, but builds on a deeper magnitude sense that manifests spatially and nonspatially mediated by magnitude, stimulus modality, and reporting condition. Number-to-space mappings—although ubiquitous in the modern world—do not seem to be rooted directly in brain evolution but have been culturally privileged and enhanced. 相似文献
952.
In this paper, two experiments are reported investigating the nature of the cognitive representations underlying causal conditional reasoning performance. The predictions of causal and logical interpretations of the conditional diverge sharply when inferences involving pairs of conditionals—such as if P1then Q and if P2then Q—are considered. From a causal perspective, the causal direction of these conditionals is critical: are the Picauses of Q; or symptoms caused byQ. The rich variety of inference patterns can naturally be modelled by Bayesian networks. A pair of causal conditionals where Q is an effect corresponds to a “collider” structure where the two causes (Pi) converge on a common effect. In contrast, a pair of causal conditionals where Q is a cause corresponds to a network where two effects (Pi) diverge from a common cause. Very different predictions are made by fully explicit or initial mental models interpretations. These predictions were tested in two experiments, each of which yielded data most consistent with causal model theory, rather than with mental models. 相似文献
953.
This study uses intraindividual variability and change methods to test theoretical accounts of self-concept and its change across time and context and to test the developmental implications of this variability. The 5-year longitudinal study of 541 youths in a rural Pennsylvania community from 3rd through 7th grade included twice-yearly assessments of self-concept (academic and social), corresponding external evaluations of competence (e.g., teacher-rated academic skills, peer-nominated "likeability"), and multiple measures of youths' overall adjustment. Multiphase growth models replicate previous research, suggesting significant decline in academic self-concept during middle school but modest growth in social self-concept from 3rd through 7th grade. Next, a new contribution is made to the literature by quantifying the amount of within-subject variability (i.e., "lability") around these linear self-concept trajectories as a between-subjects characteristic. Self-concept lability was found to associate with a general profile of poorer competence and adjustment and to predict poorer academic and social competence at the end of 7th grade above and beyond level of self-concept. Finally, there was substantial evidence that wave-to-wave changes in youths' self-concepts correspond to teacher and peer evaluations of youths' competence, that attention to peer feedback may be particularly strong during middle school, and that these relations may be moderated by between-subjects indicators of youths' general adjustment. Overall, findings highlight the utility of methods sensitive to within-subject variation for clarifying the dynamics of youths' self-system development. 相似文献
954.
Drawing from an interactionist approach and feedback research, we examine the role of developmental feedback and proactive personality on newcomer task performance and helping behavior. Data were collected from 2 high-tech joint-ventures within the information technology and manufacturing industries located in Shanghai, China. Results based on 151 newcomer-manager dyads showed that supervisor developmental feedback (SDF) positively related to newcomer helping behavior and that SDF and coworker developmental feedback interactively predicted newcomer task performance. We also found differential moderating effects of proactive personality: SDF more strongly related to helping behavior when proactive personality was lower; conversely, coworker developmental feedback more strongly related to helping behavior when proactive personality was higher. 相似文献
955.
Leca JB Gunst N Huffman M 《Journal of comparative psychology (Washington, D.C. : 1983)》2011,125(1):61-71
Defined as a spontaneous stone-directed noninstrumental manipulative behavior, and comprised of multiple one-handed and (a)symmetrical/(un)coordinated two-handed patterns, stone handling (SH) is a good candidate for the study of complexity in object manipulation. We present a cross-sectional developmental analysis of SH complexity in Japanese macaques (Macaca fuscata), through the combined investigation of bimanuality, coordination, and symmetry in hand use. Bimanual SH patterns were more frequent than unimanual patterns. Among bimanual patterns, coordinated actions were more frequent than uncoordinated ones. We recorded five asymmetrical coordinated SH patterns with manual role differentiation, a form of hand use reminiscent of complex actions involving the use of tools in monkeys and apes. Bimanuality in SH was affected by body posture. Aging individuals performed less bimanual and less coordinated SH patterns than younger individuals. Our result on senescent males performing less bimanual patterns than senescent females was consistent with sex differences found in the late deterioration of complex manual movements in other species. Although some SH patterns represent a high degree of behavioral complexity, our results suggest that SH behavior is not as complex as tool-use or tool-manufacture in other nonhuman primates and hominids. 相似文献
956.
Studies have demonstrated that maternal stress and perceptions of self-efficacy influence a mother's performance, affecting her ability to interact with her child and to understand and answer his needs. The purpose of this study was to evaluate maternal stress and the perception of self-efficacy in the mothers of infants who are cared for in child-care centers and belong to the poorest segment of the Chilean population. To this end, these aspects were studied in 121 low-income, high-social-risk mothers with children between the ages of 4 and 9 months. The final goal was to generate an explicative model of self-efficacy and maternal stress that considered characteristics of the family and the child. The results revealed that family characteristics - especially household size, per capita incomes and mother age - are more relevant for explaining maternal self-efficacy and stress. The findings and implications for practice are discussed. 相似文献
957.
Despite the great importance of impulsivity in many childhood and adolescence disorders, there are few self-reports on child impulsivity. Recently, a modified version of Barratt's BIS-11 questionnaire adapted for children has been developed, which may be useful in assessing this personality dimension. The present study reports an adaptation of this questionnaire in a different culture (Colombia) and assesses the degree of convergence between the factor structures of both adaptations using consensus oblimin rotation. The results indicate not only that the factor structure of the test remains stable across both adaptations, and that two of the three scales in the Colombian version show acceptable reliabilities, but also that cultural and linguistic issues are important in test adaptation even when the same language is used. 相似文献
958.
Addamo PK Farrow M Bradshaw JL Moss S Georgiou-Karistianis N 《Brain and cognition》2010,74(3):358-364
Motor overflow refers to involuntary movement or muscle activity coinciding with voluntary movement. We examined whether 16 young adults (18-30 years) and 16 older adults (50-80 years) could voluntarily inhibit overflow. Participants performed a finger pressing task, exerting 50% of their maximal force. Overflow was concurrently recorded in the non-task hand. In the first condition, participants were not made aware of their motor overflow. Then participants, though informed of it, were asked to ignore their overflow. Finally, participants were requested to inhibit overflow with, and then without visual feedback, or vice versa. Overflow was exacerbated when older adults were unaware of it, and was reduced once they were informed. For young adults there was no significant difference between these conditions. Both Age Groups could significantly reduce overflow when so requested, independent of visual feedback. Thus motor overflow can be modulated by higher order cognitive control with directed attention. 相似文献
959.
Recent reports from electrophysiological and psychophysical experiments provide evidence that repeated exposure to an ordered sequence of morphed stimuli may over time adapt a prelearned object category such that the category may generalise the entire sequence as belonging to the same object. Here, a new protocol that includes a single exposure to a morphing sequence is presented. Subjects exposed to the new protocol replaced a prelearned face with an entirely different face within just 3 days, significantly faster than in previous reports. 相似文献
960.
Recent research suggests that language evolution is a process of cultural change, in which linguistic structures are shaped through repeated cycles of learning and use by domain-general mechanisms. This paper draws out the implications of this viewpoint for understanding the problem of language acquisition, which is cast in a new, and much more tractable, form. In essence, the child faces a problem of induction, where the objective is to coordinate with others (C-induction), rather than to model the structure of the natural world (N-induction). We argue that, of the two, C-induction is dramatically easier. More broadly, we argue that understanding the acquisition of any cultural form, whether linguistic or otherwise, during development, requires considering the corresponding question of how that cultural form arose through processes of cultural evolution. This perspective helps resolve the "logical" problem of language acquisition and has far-reaching implications for evolutionary psychology. 相似文献