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871.
A software program written to collect real-time, observational data is described. The flexible program allows customized behavior codes and observational durations and simultaneously records both timed and counted events. The data are collected by means of single keystrokes, automatically stored to disk with 100th of a second resolution and summarized for each observational session. The program’s database files are dBASE III PLUS compatible and may be browsed, edited, or converted to ASCII files from the program’s main menu. Field testing demonstrated the efficiency and interobserver reliability of the program (for frequency,r=0.81; for durational behaviors,rs=0.89 and 0.96). The software operates on IBM XT/AT/PS 2s and most clones with PC/MS DOS version 2.0 or greater.  相似文献   
872.
873.
The effect of training on an observer’s ability to detect the misalignment of three points, a hypes-acuity, and to resolve a six-line grating was studied in a transfer-of-training design with observers (4 in each of two experiments) who were experienced in making psychophysical judgments of other visual stimuli. The transfer-of-training design enabled us to look for any training-based improvement. Long periods of training produced no statistically significant improvement in performance under any condition. There were small practice-based improvements, but the primary patterns indicated threshold fluctuation rather than improvement. We interpret the results to indicate that the neural mechanisms underlying three-point alignment and grating discrimination, like those for gap bisection (Klein & Levi, 1985), are not malleable to any significant extent.  相似文献   
874.
A coding scheme based on Wertsch's (1983) extension of Vygotsky's ideas about adult-child interaction in the zone of proximal development was used to analyze parent-child interaction during exploration. Sixty children, 3 to 6 years old, were videotaped while exploring novel objects in 15-min sessions with their mothers and fathers. Clusters of verbal and nonverbal behavior were used to code how participants defined the situation in each 15-s interval of each session in terms of one of nine categories. When parent-child mismatches occurred, the participants' negotiations of an intersubjective definition were coded, and child and parent questions were coded for complexity, complexity and appropriateness of response, and function. Results indicated that parent and child definitions matched almost 80% of the time, usually around exploration by the child with attention of or collaboration by the adult. Fathers tended to be more didactic than mothers.  相似文献   
875.
Gennclus: New models for general nonhierarchical clustering analysis   总被引:6,自引:0,他引:6  
A general class of nonhierarchical clustering models and associated algorithms for fitting them are presented. These (metric) clustering models generalize the Shepard-Arabie Additive Clusters model in allowing for: (1). either overlapping or nonoverlapping clusters; (2). either symmetric (one-way clustering) or nonsymmetric (two-way clustering) proximities (input data); and, (3). either symmetric or diagonal weights. The GENNCLUS algorithms utilize alternating least-squares methods combining ordinary and constrained least-squares, nonlinear constrained mathematical programming, and combinatorial optimization techniques in estimating model parameters. In addition to developing the mathematical bases of these models, a comprehensive set of Monte Carlo simulations of the different models is reported. Two applications concerning brand-switching data and celebrity-brand proximities are discussed. Finally, extensions to three-way models, nonmetric analyses, and other model specifications are provided.Wayne S. DeSarbo is a Member of Technical Staff in the Mathematics and Statistics Research Center at Bell Laboratories in Murray Hill, N.J. I wish to thank R. Gnanadesikan, J. D. Carroll, and P. Arabie for their comments on a previous draft of this paper. I also wish to acknowledge the computer assistance provided by Linda Clark. Finally, I wish to thank the reviewers and editor for their very complete reviews and comments.  相似文献   
876.
A brief review is provided of the capacity of neural tissue transplants to reinnervate the deafferented hippocampus and repair functional deficits induced by the lesion. The techniques for transplantation of solid pieces of embryonic septum, locus coeruleus or raphe nuclei, or tissue suspensions of embryonic septum, to the adult rat hippocampus are described. Such grafts manifest good long-term survival, provide a good reinnervation of the hippocampus that is histochemically and biochemically appropriate and specific, can establish ultrastructural synaptic contacts with the host, and are electrophysiologically active. Rats with septal grafts manifest recovery of the capacity to learn certain aspects of radial 8-arm maze, T-maze alternation and Morris water-maze tasks. Rats with locus coeruleus grafts manifest an amelioration of lesion-induced hyperactivity. It is concluded that neural tissue transplantation provides a powerful new tool in the study of the functional organization of the hippocampus and its various neurotransmitter-specific afferent systems.  相似文献   
877.
We here review briefly the evidence suggesting a key role for the medial preoptic area in the regulation of sexual behaviour, with particular emphasis on the behavioural consequences of preoptic degeneration.  相似文献   
878.
Functionalism and type-type identity theories   总被引:1,自引:0,他引:1  
Conclusion Token-token identity theorists do not and need not deny that it may frequently be the same (kind of) brain state which on different occasions fills the functional rôle definitive of a given mental state. That is not at issue. What is at issue is whether functionally-oriented identity theorists should make two claims or three claims.The two claims they customarily make are, first, that each instance of a mental state is an instance of a brain state, and, secondly, that being in a mental state is having in one a state filling the relevant functional rôle. But to be in a mental state is to have that state in one. To be in pain is to have pain, to desire water is to have desire for water, and so on; just as to be poisoned is to have poison in you. (It is to have what is poison for you at the time, of course; and likewise for pain, desire and so on.)Our paper has been about a third sort of claim — relating particularly not to being in a mental state, nor to instances of that state, but to the mental state itself. We have argued that functionally-oriented identity theorists can and should make, in addition to the first two claims, the third type-type identity claim that mental states are brain states. Consequently a token brain state is a token of pain in a derivative sense. What makes it a token of pain is that it is a token of the type of brain state which realizes the pain-rôle for the organism at the time.  相似文献   
879.
880.
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