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891.
892.
The effectiveness of fixed-time delivery of attention to increase the on-task behavior of 2 students in general education was examined. The teacher in this study provided attention to students on a 5-min fixed-time schedule and responded to students in her typical manner between cued intervals. An ABAB withdrawal design was used to test the effects of the intervention. The results of this study indicate that a fixed-time schedule of attention was effective in increasing students’ on-task behavior and decreasing their off-task behavior. Implications of the study for research and practice are discussed.  相似文献   
893.
894.
This article examines the contemporary phenomenon of imagining a world from which people have been removed. Such a trend speaks to a utopian impulse, but one that is not comparable to traditional utopian ideas. What does the popularity of books like The World without Us or documentaries such as The Future is Wild, Aftermath: Population Zero, and Life after People say about the current status of utopian ideals, environmental thought, and our cultural understanding of humanity's place in the nature order?  相似文献   
895.
The present study examines the predictive and incremental validity of Violence Risk Appraisal Guide scores in a sample of 328 male and 145 female jail inmates held on felony charges. Significant gender differences were observed in VRAG item and total score means, as well as in correlations between the VRAG and concurrent measures of aggression. VRAG scores significantly predicted institutional misconduct during incarceration and recidivism in the first year postrelease for male inmates but not for female inmates. In terms of incremental validity, VRAG scores predicted institutional misconduct and recidivism beyond that accounted for by psychopathy for male inmates but not for female inmates. Implications for clinical practice and future research are discussed.  相似文献   
896.
In response to concerns with existing procedures for measuring strategic control over implicit knowledge in artificial grammar learning (AGL), we introduce a more stringent measurement procedure. After two separate training blocks which each consisted of letter strings derived from a different grammar, participants either judged the grammaticality of novel letter strings with respect to only one of these two grammars (pure-block condition), or had the target grammar varying randomly from trial to trial (novel mixed-block condition) which required a higher degree of conscious flexible control. Random variation in the colour and font of letters was introduced to disguise the nature of the rule and reduce explicit learning. Strategic control was observed both in the pure-block and mixed-block conditions, and even among participants who did not realise the rule was based on letter identity. This indicated detailed strategic control in the absence of explicit learning.  相似文献   
897.
The use of multi-method, multi-informant assessment is a hallmark of research in child development and mental health; however, many research strategies such as population surveys require brief assessment tools. The Alabama Parenting Questionnaire (APQ) is a popular measure of empirically identified aspects of positive and negative parenting styles important to conduct problems in children. A brief version exists, however it does not measure all relevant parenting domains, and it has not been validated for child reports. We evaluated validity of the brief parent and child report version of the complete five subscale version of the APQ in a sample of 208 children aged between 9 and 17, at risk for conduct problems and antisocial behaviour. The results showed that all five dimensions of parenting can be measured using a brief 15 item version; specifically child and parent reports converged as expected and discriminated high from low conduct problem children using parent and teacher reports. Only child reports converged with independent observations of parenting behaviour, supporting previous research showing that child reports of parenting are particularly important. Finally, results did not support the typical methods used for combining child and parent reports into one index.  相似文献   
898.
The goal of the present study was to elucidate the role of the human striatum in learning via reward and punishment during an associative learning task. Previous studies have identified the striatum as a critical component in the neural circuitry of reward-related learning. It remains unclear, however, under what task conditions, and to what extent, the striatum is modulated by punishment during an instrumental learning task. Using high-resolution functional magnetic resonance imaging (fMRI) during a reward- and punishment-based probabilistic associative learning task, we observed activity in the ventral putamen for stimuli learned via reward regardless of whether participants were correct or incorrect (i.e., outcome). In contrast, activity in the dorsal caudate was modulated by trials that received feedback--either correct reward or incorrect punishment trials. We also identified an anterior/posterior dissociation reflecting reward and punishment prediction error estimates. Additionally, differences in patterns of activity that correlated with the amount of training were identified along the anterior/posterior axis of the striatum. We suggest that unique subregions of the striatum--separated along both a dorsal/ventral and anterior/posterior axis--differentially participate in the learning of associations through reward and punishment.  相似文献   
899.
The GluR1 subunit of the AMPA receptor is required for hippocampal-dependent memory formation, emotional learning and synaptic plasticity. Recent work has shown that GluR1-independent synaptic plasticity is mediated by nitric oxide. Nitric oxide activity is influenced by estrogen. It is unknown whether this gender-dependent effect conveys a gender dimorphic requirement of GluR1 for learning. This hypothesis was tested in two behavioral paradigms. In Experiment 1, the retention of contextual fear conditioning was impaired in male but not female GluR1 knockout mice. In Experiment 2, GluR1 knockout mice made significantly more arm entry errors during acquisition of a radial-arm watermaze task. This deficit was independent of gender. These results indicate that some forms of learning are gender dimorphic in GluR1 knockout mice. The results are discussed with reference to task and gender-specific interactions between GluR1 receptor intracellular signalling pathways.  相似文献   
900.
The efficiency of somatic energy metabolism is correlated with cognitive change over the lifespan. This relationship is bidirectional, with improved overall fitness associated with enhanced synaptic function and neuroprotection, and synaptic endangerment occurring in the context of impaired energy metabolism. In this review, we discuss recent advancements in the fields of exercise, dietary energy intake and diabetes, as they relate to neuronal function in the hippocampus. Because hippocampal neurons have energy requirements that are relatively higher than those of other brain regions, they are uniquely poised to benefit from exercise, and to be harmed by diabetes. We view exercise and dietary energy restriction as being associated with enhanced hippocampal plasticity at one end of a continuum, with obesity and diabetes accompanied by cognitive impairment at the other end of the continuum. Understanding the mechanisms for this continuum may yield novel therapeutic targets for the prevention and treatment of cognitive decline following aging, disease, or injury.  相似文献   
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