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821.
The 2011 Varsity Medical Debate, between Oxford and Cambridge Universities, brought students and faculty together to discuss the waiving of patents for antiretroviral therapies in the developing world. With an estimated 29.5 million infected by Human Immunodeficiency Virus (HIV) in low- and middle-income countries and only 5.3 million of those being treated, the effective and equitable distribution of anti-retroviral therapy (ART) is an issue of great importance. The debate centred around three areas of contention. Firstly, there was disagreement about whether patents were the real barrier to the access of anti-retroviral therapy in the developing world. Secondly, there were differing views on the effectiveness of a patent pool. Thirdly, concerns were raised over the impact of waiving patents on research to produce new and better anti retro-viral drugs.  相似文献   
822.
The nature of capacity limits (if any) in visual search has been a topic of controversy for decades. In 30 years of work, researchers have attempted to distinguish between two broad classes of visual search models. Attention-limited models have proposed two stages of perceptual processing: an unlimited-capacity preattentive stage, and a limited-capacity selective attention stage. Conversely, noise-limited models have proposed a single, unlimited-capacity perceptual processing stage, with decision processes influenced only by stochastic noise. Here, we use signal detection methods to test a strong prediction of attention-limited models. In standard attention-limited models, performance of some searches (feature searches) should only be limited by a preattentive stage. Other search tasks (e.g., spatial configuration search for a "2" among "5"s) should be additionally limited by an attentional bottleneck. We equated average accuracies for a feature and a spatial configuration search over set sizes of 1-8 for briefly presented stimuli. The strong prediction of attention-limited models is that, given overall equivalence in performance, accuracy should be better on the spatial configuration search than on the feature search for set size 1, and worse for set size 8. We confirm this crossover interaction and show that it is problematic for at least one class of one-stage decision models.  相似文献   
823.
This article illustrates a dissociation between the perceived attributes of an object and the ability of those attributes to guide the deployment of attention in visual search. Orientation is an attribute that guides search. Thus, a vertical line will “pop out” amid horizontal distractors. Amodal completion can create perceptually convincing oriented stimuli when two elements appear to form a complete object partially hidden behind an occluder. Previous work (e.g., Rensink &; Enns, Vision Research, 38, 2489–2505, 1998) has shown a preattentive role for amodal completion in search tasks. Here, we show that orientation based on perceptually compelling amodal completion may fail to guide attention. The broader conclusion is that introspection is a poor guide to the capabilities of our internal search engine.  相似文献   
824.
825.
In a series of experiments, we investigated the effect of pun humor on memory. In all experiments, the participants were exposed to knock-knock jokes in either the original form retaining the pun or in a modified form that removed the pun. In Experiment 1, the authors found that pun humor improved both recall and recognition memory following incidental encoding. In Experiment 2, they found evidence that rehearsal is not the cause of the humor effect on memory. In Experiments 3 and 4, the authors found that the constraints imposed by puns and incongruity may account for the humor effects observed. Puns constrain and limit the information that can fit in the final line of a joke and thus make recall easier.  相似文献   
826.
Thirty years of work on psychological distancing is discussed in this article. The psychological construct of psychological distance was applied to the development of children's developing representational abilities over 30 years ago [Sigel, I. E. (1970). The distancing hypothesis: A causal hypothesis for the acquisition of representational thought. In: M. R. Jones (Ed.), Miami symposium on the prediction of behavior, 1968: Effect of early experiences (pp. 99–118). Coral Gables, FL: University of Miami Press]. The construct has changed knowledge in three areas: (1) changes in the child's developmental status as a result of reflection on general properties of interactions with the world as well as maturation, (2) the effects of different modes of formal instruction in schooling on the development of children's thinking, and (3) the relationship of one's beliefs about how development occurs to behaviors with children that create “distancing experiences” for children. The distancing construct itself has been broadened further as the notion of psychological distance has been applied to areas as diverse as delay of gratification, divorce, video game play, and resolution of interpersonal conflicts [Cocking, R. R., & Renninger, K. A. (Eds.) (1993). The development and meaning of psychological distance. Hillsdale, NJ: Erlbaum]. The distancing construct was evident in Rod Cocking's own program of psychological inquiry. However, much of his legacy to the field lies in his Educational Testing Service (ETS) work that extended the usefulness of this construct for other researchers working in a variety of domains of development and in his ability to see the implications of research from this perspective for the lives of children.  相似文献   
827.
828.
Gene-environment interactions are presumed to shape human behavior during early development. However, no human research has demonstrated that such interactions lead to stable individual differences in fear responses. We tested this possibility by focusing on a polymorphism in the promoter region of the gene for the serotonin transporter (5-HTT). This polymorphism has been linked to many indices of serotonin activity. Specifically, we tested the hypothesis that an interaction between children's 5-HTT status and maternal reports of social support predicts inhibited behavior with unfamiliar peers in middle childhood. Results were consistent with this hypothesis: Children with the combination of the short 5-HTT allele and low social support had increased risk for behavioral inhibition in middle childhood.  相似文献   
829.
830.
Three patients with a typical syndrome of nonfluent primary progressive aphasia (Mesulam's syndrome) were trained daily with a remediation protocol including auditory exercises specifically designed to involve several aspects of phonological processing, a domain known to be specifically affected in the condition. The speech content of the exercises was based on the temporal theory of phonological processes according to which increasing the duration of formant transition should facilitate phoneme discrimination and phoneomic awareness. Significantly improved performance on the trained tasks was demonstrated in the three patients. Improvement further generalized to other tasks such as nonword repetition and reading. We conclude that such results (1) argue for using intensive focused therapy of language impairment in neurodegenerative disorders, (2) may constitute a good model of brain plasticity in neurodegenerative disorders in general, and (3) support theories of phonological processing emphasizing temporal features of the auditory signal.  相似文献   
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