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991.
This longitudinal study examined processes that mediate the association between maternal depressive symptoms and peer social preference during the early school years. Three hundred and fifty six kindergarten children (182 boys) and their mothers participated in the study. During kindergarten, mothers reported their level of depressive symptomatology. In first grade, teachers rated children’s emotion regulation at school and observers rated the affective quality of mother-child interactions. During second grade, children’s social preference was assessed by peer nomination. Results indicated that mothers’ level of depressive symptomatology negatively predicted their child’s social preference 2 years later, controlling for the family SES and teacher-rated social preference during kindergarten. Among European American families, the association between maternal depressive symptoms and social preference was partially mediated by maternal warmth and the child’s emotion regulation. Although the relation between maternal depressive symptoms and children peer preference was stronger among African American families than Europrean American families, its mediation by the maternal warmth and child’s emotion regulation was not found in African American families.  相似文献   
992.
Speech remains intelligible despite the elimination of canonical acoustic correlates of phonemes from the spectrum. A portion of this perceptual flexibility can be attributed to modulation sensitivity in the auditory-to-phonetic projection, although signal-independent properties of lexical neighborhoods also affect intelligibility in utterances composed of words. Three tests were conducted to estimate the effects of exposure to natural and sine-wave samples of speech in this kind of perceptual versatility. First, sine-wave versions of the easy and hard word sets were created, modeled on the speech samples of a single talker. The performance difference in recognition of easy and hard words was used to index the perceptual reliance on signal-independent properties of lexical contrasts. Second, several kinds of exposure produced familiarity with an aspect of sine-wave speech: (a) sine-wave sentences modeled on the same talker; (b) sine-wave sentences modeled on a different talker, to create familiarity with a sine-wave carrier; and (c) natural sentences spoken by the same talker, to create familiarity with the idiolect expressed in the sine-wave words. Recognition performance with both easy and hard sine-wave words improved after exposure only to sine-wave sentences modeled on the same talker. Third, a control test showed that signal-independent uncertainty is a plausible cause of differences in recognition of easy and hard sine-wave words. The conditions of beneficial exposure reveal the specificity of attention underlying versatility in speech perception.  相似文献   
993.
Within-subjects procedures with rats assessed the associative structures acquired during conditioning trials in which the interval between the stimuli and food was either short or long (i.e., A-10 s→food and B-40 s→food). In Experiments 1 and 2, after these conditioning trials, A and B served as second-order reinforcers for 2 further stimuli (i.e., X→A and Y→B); whereas Experiment 3 used a sensory preconditioning procedure in which X→A and Y→B trials occurred before the conditioning trials, and rats were finally tested with X and Y. In each experiment, Y elicited greater responding at test than did X. This finding supports the contention that the long-lived trace of B (associated with food on B-40 s→food trials) is more similar to the memory of B that was associatively provoked by Y, than is the short-lived trace of A (associated with food on A-10 s→food trials) to the memory of A that was associatively provoked by X. These conclusions were reinforced by the effects of a neural manipulation that disrupted discrimination learning involving the short traces of stimuli but not the long traces of the same stimuli.  相似文献   
994.
To examine if animals could learn action-like categorizations in a manner similar to noun-based categories, eight pigeons were trained to categorize rates of object motion. Testing 40 different objects in a go/no-go discrimination, pigeons were first trained to discriminate between fast and slow rates of object rotation around their central y-axis. They easily learned this velocity discrimination and transferred it to novel objects and rates. This discrimination also transferred to novel types of motions including the other two axes of rotation and two new translations around the display. Comparable tests with rapid and slow changes in the objects' size, color, and shape failed to support comparable transfer. This difference in discrimination transfer between motion-based and property-based changes suggests the pigeons had learned motion concept rather than one based on change per se. The results provide evidence that pigeons can acquire an understanding of motion-based actions, at least with regard to the property of object velocity. This may be similar to our use of verbs and adverbs to categorize different classes of behavior or motion (e.g., walking, jogging, or running slow vs. fast).  相似文献   
995.
When conditioning involves a consistent temporal relationship between the conditioned stimulus (CS) and unconditioned stimulus (US), the expression of conditioned responses within a trial peaks at the usual time of the US relative to the CS. Here we examine the temporal profile of responses during conditioning with variable CS-US intervals. We conditioned stimuli with either uniformly distributed or exponentially distributed random CS-US intervals. In the former case, the frequency of each CS-US interval within a specified range is uniform but the momentary probability of the US (the hazard function) increases as time elapses during the trial; with the latter distribution, short CS-US intervals are more frequent than longer intervals, but the momentary probability of the US is constant across time within the trial. We report that, in a magazine approach paradigm, rats' response rates remained stable as time elapses during the CS when the CS-US intervals were uniformly distributed, whereas their response rates declined when the CS-US intervals were exponentially distributed. In other words, the profile of responding during the CS matched the frequency distribution of the US times, not the momentary probability of the US during the CS. These results are inconsistent with real-time associative models, which predict that associative strength tracks the momentary probability of the US, but may provide support for timing models of conditioning in which conditioned responding is tied to remembered times of reinforcement.  相似文献   
996.
von Hippel W  Trivers R 《The Behavioral and brain sciences》2011,34(1):1-16; discussion 16-56
In this article we argue that self-deception evolved to facilitate interpersonal deception by allowing people to avoid the cues to conscious deception that might reveal deceptive intent. Self-deception has two additional advantages: It eliminates the costly cognitive load that is typically associated with deceiving, and it can minimize retribution if the deception is discovered. Beyond its role in specific acts of deception, self-deceptive self-enhancement also allows people to display more confidence than is warranted, which has a host of social advantages. The question then arises of how the self can be both deceiver and deceived. We propose that this is achieved through dissociations of mental processes, including conscious versus unconscious memories, conscious versus unconscious attitudes, and automatic versus controlled processes. Given the variety of methods for deceiving others, it should come as no surprise that self-deception manifests itself in a number of different psychological processes, and we discuss various types of self-deception. We then discuss the interpersonal versus intrapersonal nature of self-deception before considering the levels of consciousness at which the self can be deceived. Finally, we contrast our evolutionary approach to self-deception with current theories and debates in psychology and consider some of the costs associated with self-deception.  相似文献   
997.
An estimated 8 million children, mostly birth to approximately 6-8 years of age, live in institutions worldwide. While institutional environments vary, certain characteristics are common, including relatively large groups; high children:caregiver ratios; many and frequently changing caregivers; homogeneous grouping by age and disability status; periodic graduations to new groups of peers and caregivers; and an "institutional style of caregiving" that minimizes talking, provides rather dispassionate perfunctory care, and offers little warm, sensitive, contingently-responsive caregiver-child interactions. The development of children in residence is usually delayed, sometimes extremely so, in every physical and behavioral domain. Although efforts are being made in many countries to care for children without permanent parents in family environments (e.g., domestic adoption, foster and kinship care, reunification with biological parents), it is not likely that transitions to family alternatives will be completed in all countries in the near future; thus, institutions are likely to exist for many years if not decades. But institutions need not operate in the current manner; they can be modified to be substantially more family-like in structure and in the behavior of caregivers. Research indicates that when such changes are made the development of children, both typically developing and those with special needs, is improved substantially. Based on the available literature and the authors' experience, this paper describes steps that can be taken to implement such changes in residential institutions for infants and young children.  相似文献   
998.
With the aim of identifying and examining both converging (matched relationship quality across one's set of relationships) and non-converging (mixed relationship quality across one's set of relationships), the present study used a pattern-centered approach to examine the different ways adolescent relationships pattern together among a large, national sample of U.S adolescents (aged 13-19). The study also examined how adolescent adjustment and young adult relationship quality varied across the different relationship patterns or constellations. The current study used latent class analysis and data from Add Health (n = 4,233), a national U.S. longitudinal study that spans adolescence and young adulthood, to uncover heterogeneity in adolescent relations with parents, friends, romantic partners, peers, and teachers. As predicted, patterns of both convergence and non-convergence were found, though patterns of non-convergence were more common than expected. Some patterns of non-convergence appear more stable (i.e., similar pattern found during both adolescence and young adulthood) than others. Also, no "high" converging pattern was found, indicating that few adolescents have "first-rate" relations in every relational domain.  相似文献   
999.
Current models of health anxiety suggest that fear resulting from false alarms to perceived threats to one's health results in the development of hypochondriasis and related disorders. Disgust has been proposed as an affective response that may function as an etiological and maintenance mechanism in health anxiety. Moreover, the way in which an individual perceives the disgust response (disgust sensitivity) may affect health anxiety, separately from their likelihood of experiencing disgust (disgust propensity). The present study utilized multiple hierarchical regression analysis to investigate the degree to which self-reported disgust sensitivity and disgust propensity differentially predict elevated health anxiety in a sample of 620 non-treatment-seeking undergraduates. Further, this effect is tested in comparison to that of anxiety sensitivity, a construct demonstrated to be strongly related to health anxiety. Analyses indicate that disgust sensitivity, rather than disgust propensity, is primarily responsible for this relation. An additional analysis tested the specificity of disgust sensitivity relative to anxiety sensitivity. Disgust sensitivity was no longer significant after including anxiety sensitivity in the model. Suggestions for further evaluation of this relation are provided. These results suggest that although disgust sensitivity may appear related to health anxiety, this relation may be confounded by anxiety sensitivity.  相似文献   
1000.
Most mathematics assignments consist of a group of problems requiring the same strategy. For example, a lesson on the quadratic formula is typically followed by a block of problems requiring students to use that formula, which means that students know the appropriate strategy before they read each problem. In an alternative approach, different kinds of problems appear in an interleaved order, which requires students to choose the strategy on the basis of the problem itself. In the classroom-based experiment reported here, grade 7 students (n = 140) received blocked or interleaved practice over a nine-week period, followed two weeks later by an unannounced test. The mean test scores were greater for material learned by interleaved practice rather than by blocked practice (72 % vs. 38 %, d = 1.05). This interleaving effect was observed even though the different kinds of problems were superficially dissimilar from each other, whereas previous interleaved mathematics studies had required students to learn nearly identical kinds of problems. We conclude that interleaving improves mathematics learning not only by improving discrimination between different kinds of problems, but also by strengthening the association between each kind of problem and its corresponding strategy.  相似文献   
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