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801.
Recent studies indicate that more men than women run fast relative to sex- specific world records and that this sex difference has been historically stable in elite U.S. runners. These findings have been hypothesized to reflect an evolved male predisposition for enduring competitiveness in "show-off" domains. The current study tests this hypothesis in non-elite runners by analyzing 342 road races that occurred from 1981-2006, most in or near Buffalo, NY. Both absolutely and as a percentage of same-sex finishers, more men ran relatively fast in most races. During the 1980s, as female participation surged, the difference in the absolute number of relatively fast men and women decreased. However, this difference was stable for races that occurred after 1993. Since then, in any given race, about three to four times as many men as women ran relatively fast. The stable sex difference in relative performance shown here for non-elites constitutes new support for the hypothesis of an evolved male predisposition for enduring competitiveness.  相似文献   
802.
Although facial expressions are thought to vary in their functional impact on perceivers, experimental demonstration of the differential effects of facial expressions on behavior are lacking. In the present study, we examined the effects of exposure to facial expressions on visual search efficiency. Participants (n = 31) searched for a target in a 12 location circle array after exposure to an angry, disgusted, fearful, happy, or neutral facial expression for 100 ms or 500 ms. Consistent with predictions, exposure to a fearful expression prior to visual search resulted in faster target identification compared to exposure to other facial expressions. The effects of other facial expressions on visual search did not differ from each other. The fear facilitating effect on visual search efficiency was observed at 500-ms but not at 100-ms presentations, suggesting a specific temporal course of the facilitation. Subsequent analysis also revealed that individual differences in fear of negative evaluation, trait anxiety, and obsessive-compulsive symptoms possess a differential pattern of association with visual search efficiency. The experimental and clinical implications of these findings are discussed.  相似文献   
803.
Sensorimotor synchronization is a crucial function for human daily activities, which relies on the ability of predicting external events. Synchronization performance, as assessed in finger-tapping (FT) tasks, is characterized by an anticipation tendency, as the tap generally precedes the pacing event. This synchronization error (SE) depends on many factors, in particular on the features of the pacing stimulus. Interest is growing in the facilitation effect that action observation has on motor execution. So far, neuroimaging and neurophysiology studies of motor priming via action observation have mainly employed tasks requiring single action instances. The impact of action observation on motor synchronization to periodic stimuli has not yet been tested; to this aim, a synchronization FT task may be an eligible probing task. The purpose of this study was to characterize a biological pacer at the behavioral level and provide information for those interested in studying the brain processes of continuous observation/execution coupling in timed actions using FT tasks. We evaluated the influence of the biological appearance of a pacer (a tapping finger) on SE, when compared to an abstract, kinematically equivalent pacer (a tilting hinged bar) and a more standard stimulus (a pulsating dot). We showed that the continuous visual display of a biological pacer yields comparable results to the abstract pacer, and a more robust performance and larger anticipations than a traditional pulsating stimulus.  相似文献   
804.
Trials in a temporal two-interval forced-choice discrimination experiment consist of two sequential intervals presenting stimuli that differ from one another as to magnitude along some continuum. The observer must report in which interval the stimulus had a larger magnitude. The standard difference model from signal detection theory analyses poses that order of presentation should not affect the results of the comparison, something known as the balance condition (J.-C. Falmagne, 1985, in Elements of Psychophysical Theory). But empirical data prove otherwise and consistently reveal what Fechner (1860/1966, in Elements of Psychophysics) called time-order errors, whereby the magnitude of the stimulus presented in one of the intervals is systematically underestimated relative to the other. Here we discuss sensory factors (temporary desensitization) and procedural glitches (short interstimulus or intertrial intervals and response bias) that might explain the time-order error, and we derive a formal model indicating how these factors make observed performance vary with presentation order despite a single underlying mechanism. Experimental results are also presented illustrating the conventional failure of the balance condition and testing the hypothesis that time-order errors result from contamination by the factors included in the model.  相似文献   
805.
Compulsive hoarding is characterized by the acquisition of, and failure to discard, a large number of possessions and clutter that prevents the use of living spaces as intended. Current successful treatments such as individual and group cognitive-behavioral therapy are lengthy and costly, requiring a time commitment ranging from four to twelve months, trained clinicians to administer treatment, and multiple home visits. Nonprofessional interventions may provide a cost-effective pre-treatment, adjunct, or alternative for individuals who want to work on hoarding problems but are unable or unwilling to engage in treatment. The purpose of the present study was to investigate the effectiveness of an innovative program consisting of a 13-session non-professionally facilitated biblio-based, action-oriented support group using Tolin, Frost, and Steketee’s (2007b) self-help book. In study 1, seventeen self-identified hoarding participants experienced significant decreases in clutter, difficulty discarding, and excessive acquisition from pre-treatment to post-treatment, with reductions evident at mid-treatment. Study 2 replicated the findings of study 1 using interview and observational measures taken in participants’ homes. These findings suggest that a facilitated biblio-based group may be a promising intervention for hoarding disorder.  相似文献   
806.
Background. Many countries rely on immigrants for population growth and to maintain a skilled workforce. However, many such immigrants face literacy‐related barriers to success in education and in the labour force. Aims. This meta‐analysis reviews experimental and quasi‐experimental studies to examine strategies for teaching English literacy to immigrant students. Method. Following an exhaustive and systematic search for studies meeting pre‐determined inclusion criteria, two researchers independently extracted data from 26 English as a Second Language (ESL) studies involving 3,150 participants. These participants consisted of ESL immigrant students in kindergarten through grade 6 who were exposed to English literacy instructional interventions. Measured outcomes were reading and writing. Results and Conclusions. Mean effect sizes vary from small to large, depending on instructional interventions and outcome constructs. Across several different grade levels, settings, and methodological features, pedagogical strategies used in teaching ESL to immigrant students are associated with increased competence in reading and writing. Collaborative reading interventions, in which peers engage in oral interaction and cooperatively negotiate meaning and a shared understanding of texts, produced larger effects than systematic phonics instruction and multimedia‐assisted reading interventions. The results show that the pedagogical strategies examined in this meta‐analysis produced statistically significant benefits for students in all grade levels. The findings also show that students from low socio‐economic status (SES) background benefit from ESL literacy interventions. However, significant heterogeneity was found in each subset. Educators and policy makers are encouraged to consider specific school contexts when making decisions about optimal pedagogical strategies. It is possible that contextual factors as well as ESL learner characteristics may influence the effectiveness of these strategies. To ensure literacy acquisition for immigrant students whose primary language is not English, it is important to continue to research successful literacy practices in ways that better inform educators and policy makers.  相似文献   
807.
A brief training package consisting of modeling, rehearsal, and feedback was evaluated to train caregivers to use incidental teaching to teach 3 children with autism to request an item or activity. The training package improved correct implementation of the incidental teaching procedure by caregivers. In addition, probes indicated that caregivers could apply these skills to teach the child an additional skill.  相似文献   
808.
809.
The present study examined the relationship between hand preference degree and direction, functional language lateralization in Broca’s and Wernicke’s areas, and structural measures of the arcuate fasciculus. Results revealed an effect of degree of hand preference on arcuate fasciculus structure, such that consistently-handed individuals, regardless of the direction of hand preference, demonstrated the most asymmetric arcuate fasciculus, with larger left versus right arcuate, as measured by DTI. Functional language lateralization in Wernicke’s area, measured via fMRI, was related to arcuate fasciculus volume in consistent-left-handers only, and only in people who were not right hemisphere lateralized for language; given the small sample size for this finding, future investigation is warranted. Results suggest handedness degree may be an important variable to investigate in the context of neuroanatomical asymmetries.  相似文献   
810.
Although worry is central to the diagnosis of generalized anxiety disorder (GAD), it is also commonly observed in other anxiety disorders. In this meta-analytic review, we empirically evaluated the extent to which worry is specific to GAD relative to patients with other anxiety disorders, those with other psychiatric disorders, and nonpsychiatric controls. A total of 47 published studies (N = 8,410) were included in the analysis. The results yielded a large effect size indicating greater severity/frequency of worry, meta-worry, and domains of worry among anxiety disorder patients v. nonpsychiatric controls (d = 1.64). In contrast to the many differences emerging from comparisons between anxiety disordered patients and nonpsychiatric controls, when anxiety disordered patients were compared to people with other psychiatric disorders they differed only on severity/frequency and not on meta-worry or domains of worry. A large effect size indicating greater severity/frequency of worry, meta-worry, and domains of worry among patients with GAD v. nonpsychiatric controls was also found (d = 2.05). However, differences between GAD and those with other psychiatric disorders also emerged for severity/frequency of worry. GAD was associated with greater worry difficulties than other anxiety disorders, which generally did not differ from those with other psychiatric disorders and each other. The implications of these findings for conceptualizing worry in GAD and other anxiety disorders, and the potentially moderating effects of age and gender are discussed.  相似文献   
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