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991.
Thirty-one 8- and 9-year-old children selected for dyscalculia, reading difficulties or both, were compared to controls on a range of basic number processing tasks. Children with dyscalculia only had impaired performance on the tasks despite high-average performance on tests of IQ, vocabulary and working memory tasks. Children with reading disability were mildly impaired only on tasks that involved articulation, while children with both disorders showed a pattern of numerical disability similar to that of the dyscalculic group, with no special features consequent on their reading or language deficits. We conclude that dyscalculia is the result of specific disabilities in basic numerical processing, rather than the consequence of deficits in other cognitive abilities.  相似文献   
992.
This study examined the effect of provocateurs' emotion displays on first through fourth graders' social information processing (SIP). Rating and nomination sociometric techniques were used to identify rejected-aggressive, rejected-nonaggressive, average-nonaggressive, and popular-nonaggressive groups. Children viewed videotaped ambiguous provocation situations in which provocateurs' emotion displays were varied systematically. After each vignette, children's recall of story details, attribution of intent, and problem-solving responses were obtained. Half of the children were randomly assigned to a condition where they were asked directly about provocateurs' emotions, and the remaining children were not asked about provocateurs' feelings. Results revealed both developmental and social adjustment differences in SIP. In addition, provocateurs' emotion displays and asking versus not asking about those displays influenced multiple aspects of SIP.  相似文献   
993.
Improved recall has consistently been demonstrated following motor activation at encoding (SPT), compared to traditional verbal learning (VT). Enhancements of item-specific processing and relational processing have been proposed as possible mechanisms to account for this SPT effect. There is ample evidence supporting the notion of enhanced item-specific processing, however it is still unclear whether enhancement of relational processing contributes to improved recall. In the present study, 2 experiments were designed to address this issue. In Experiment 1, memory under 2 encoding conditions (VT vs. SPT) and 3 recall conditions (free recall vs. category-cued recall vs. verb-cued recall) were studied in 3 large samples (N= 500-600). Experiment 2 replicated the findings of Experiment 1, and controlled for the use of actual objects, short-term memory effects, and carryover effects, in Experiment 1. The results in both experiments showed an interaction between type of encoding and type of recall. Verb-cued recall was affected differently by SPT encoding, as compared to category-cued recall and free recall. The results indicate that enhanced integration between verb and noun is an effect of SPT encoding, whereas enhanced relational processing is not.  相似文献   
994.
Summary  Big History – an integral conception of the past since the Big Bang until today – is a novel subject of cross-disciplinary interest. The concept was construed in the 1980–1990s simultaneously in different countries, after relevant premises had matured in the sciences and humanities.Various versions and traditions of Big History are considered in the article. Particularly, most of the Western authors emphasize the idea of equilibrium, and thus reduce cosmic, biological, and social evolution to the mass-energy processes; the informational parameter involving all mental and spiritual aspects are seen as epiphenomena of material structures” complication that do not play their own role in evolution. In Russian tradition ascending to A. Bogdanov, E. Bauer, I. Prigogine, and E. Jantsch, sustainable non-equilibrium patterns are used. This implies attention to the pan-material sources and evolution of mental capacities and spiritual culture (as basic anti-entropy instruments) and humans” growing intervention in the material processes on Earth and outside it.The non-equilibrium approach in the context of modern control and self-organization theories, alters the portrayal of the past, and still more dramatically, estimation of the civilization’s potential perspectives.  相似文献   
995.
An approach based on Skinner's (1957) theory of verbal behavior has been developed to understand and teach elementary communication skills to children with autism and developmental disabilities (Sundberg & Partington, 1998). However, few studies have directly examined the characteristics of emerging language in children with developmental disabilities. The purpose of this study was to develop and evaluate an assessment for identifying the elementary functions of vocal speech in children. Participants were 4 children with developmental disabilities, aged 6 years to 12 years, who exhibited at least one distinguishable vocal response (word or phrase) frequently in the natural environment. The assessment focused on three verbal operants delineated by Skinner (mand, tact, and intraverbal). One or more functions were identified for at least one vocal response of each child. Results suggested that this assessment would be useful for (a) evaluating Skinner's theory, (b) guiding decisions about language training for individual children, and (c) studying the nature of expressive language development in children with developmental disabilities.  相似文献   
996.
We present a detailed process theory of the moment-by-moment working-memory retrievals and associated control structure that subserve sentence comprehension. The theory is derived from the application of independently motivated principles of memory and cognitive skill to the specialized task of sentence parsing. The resulting theory construes sentence processing as a series of skilled associative memory retrievals modulated by similarity-based interference and fluctuating activation. The cognitive principles are formalized in computational form in the Adaptive Control of Thought–Rational (ACT–R) architecture, and our process model is realized in ACT–R. We present the results of 6 sets of simulations: 5 simulation sets provide quantitative accounts of the effects of length and structural interference on both unambiguous and garden-path structures. A final simulation set provides a graded taxonomy of double center embeddings ranging from relatively easy to extremely difficult. The explanation of center-embedding difficulty is a novel one that derives from the model' complete reliance on discriminating retrieval cues in the absence of an explicit representation of serial order information. All fits were obtained with only 1 free scaling parameter fixed across the simulations; all other parameters were ACT–R defaults. The modeling results support the hypothesis that fluctuating activation and similarity-based interference are the key factors shaping working memory in sentence processing. We contrast the theory and empirical predictions with several related accounts of sentence-processing complexity.  相似文献   
997.
Little is known about whether infants perceive meter, the underlying temporal structure of music. We employed a habituation paradigm to examine whether 7-month-old infants could categorize rhythmic and melodic patterns on the basis of the underlying meter, which was implied from event and accent frequency of occurrence. In Experiment 1, infants discriminated duple and triple classes of rhythm on the basis of implied meter. Experiment 2 replicated this result while controlling for rhythmic grouping structure, confirming that infants perceived metrical structure despite occasional ambiguities and conflicting group structure. In Experiment 3, infants categorized melodies on the basis of contingencies between metrical position and pitch. Infants presented with metrical melodies detected reversals of pitch/meter contingencies, while infants presented with non-metrical melodies showed no preference. Results indicate that infants can infer meter from rhythmic patterns, and that they may use this metrical structure to bootstrap their knowledge acquisition in music learning.  相似文献   
998.
Effects of emotional valence on attention have been shown to occur even when stimuli are presented outside awareness. The impact of negative valence on stimulus processing has been demonstrated to be particularly salient in anxiety. Therefore, it has been hypothesized that compared to nonanxious individuals, anxious individuals have an enhanced ability to detect the valence of negative stimuli. However, it remains unclear whether anxious individuals are better at identifying the valence of threatening stimuli or, rather, more likely to label ambiguous stimuli as threatening. To investigate these hypotheses, high and low anxious participants categorized lexical stimuli as "safe" or "dangerous." Stimuli were presented at durations that allowed for both conscious (unmasked) and nonconscious (masked) processing. Results show that on masked trials, anxious individuals evidenced an enhanced ability to correctly classify threatening information, whereas nonanxious participants demonstrated an enhanced ability to correctly classify neutral or positive information. Signal detection analyses indicated results were explained by a response bias, whereby anxious individuals were more likely than nonanxious individuals to categorize masked words as threatening and nonanxious individuals were more likely to categorize masked words as nonthreatening. No group differences for nonword stimuli emerged, suggesting that anxiety-related response bias tendencies are activated only after detection of a weak semantic signal.  相似文献   
999.
This paper reviews recent findings about how rats navigate by learning to discriminate among locations. The assumption underlying the experiments and their interpretation is that the information required to do this is learned by three independent, parallel memory systems. One system processes cognitive information (or "knowledge"), a second system processes reinforced stimulus-response associations and a third processes Pavlovian conditioned responses in the form of stimulus-affect associations. The information stored in each system produces behavior that, in some cases, results in a location discrimination. The present experiments focus on three factors that influence what each system learns and whether the resulting memory produces behavior that results in a location discrimination. One factor is whether the locations to be discriminated can be identified by unique, unambiguous stimuli or whether they are ambiguously associated with the same stimuli. The second factor is whether the stimuli are observed passively or whether the rats move among them, voluntarily or involuntarily. The third factor is whether or not the rats perform specific reinforced responses in the presence of the stimuli. Instances of co-operative behavioral outputs from memory systems that facilitate location discriminations and of competitive outputs that impede discriminations are described.  相似文献   
1000.
The performance of ADHD children on semantic category fluency (SCF) versus initial letter fluency (ILF) tasks was examined. For each participant, word production was recorded for each 15-s time slice on each task. Performance on both fluency tasks was compared to test the hypothesis that children with ADHD are characterized by a performance deficit on the ILF task because performance on this task is less automated than performance on the SCF. Children classified with ADHD (N = 20) were compared to children with other psychopathology (N = 118) and healthy controls (N = 130). Results indicated that the groups could not be differentiated by the total number of words produced in 60 s in either fluency task. As hypothesized, a significant interaction of group by productivity over time by type of fluency task was found: ADHD children had more problems finding words in the first 15 s of the IFL than did children in the other two groups, and as compared with their performance on the SCF. Results were taken to indicate that children with ADHD symptoms show a delay in the development of automating skills for processing abstract verbal information.  相似文献   
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