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911.
A simple dc shock-generating device is described. The principle of operation relies upon the mutual inductance effect between the primary and secondary coils of a transformer.  相似文献   
912.
Developments in television technology have made possible new approaches to the study of the role of visual feedback in motor control. In two experiments using a special videodisc recording and playback system, the effects of delaying for 66 msec a subject's view of his own hand during a target-directed movement was investigated. The observed effects of such visually delayed feedback compared to spatially distorted feedback produced by prisms led to three major conclusions: (a) despite the behavioral similarity (overshooting) induced by the two kinds of altered feedback, the role of each in the visual-motor control loop is different; (b) adaptation to and the after effect of the two kinds of altered feedback are based on different control mechanisms (c) the processing and use of visual information in hand control requires less time than previous experiments have indicated.  相似文献   
913.
While a current and increasingly popular trend is toward partnerships between religion and psychology in the area of mental health, and especially toward the use of psychological ideas and techniques by pastoral counselors, modern psychology and traditional religion are divided in significant ways over several normative issues. Too often these issues are minimized or overlooked. But unless these issues—which carry significant sociocultural implications as well as implications for our definitions of individual well-being—are acknowledged and subjected to critical considerations, partnerships between religion and psychology must be far more cautiously constructed and must be subjected to far more systematic thinking about the differences which separate the two.This article is based on a paper delivered at the Seventh Annual Clinical-Community Conference on Psychology and Religion at the University of Maryland in November, 1978.  相似文献   
914.
Summary In this paper I have argued that Feferman's theorem does not signify the existence of skeptic-satisfying consistency proofs. However, my argument for this is much different than other arguments (most particularly Resnik's) for the same claim. The argument that I give arises form an analysis of the notion of expression, according to which the specific character of that notion is seen as varying from one context of application (of a result of arithmetic metamathematics) to another.I want to thank Dale Gottlieb, Mike Resnik, John Corcoran, Nicolas Goodman and Stewart Shapiro for careful and helpful commentary on an ancestor of this paper that was delivered at the Western Division Meetings of the APA in 1977.  相似文献   
915.
916.
How maintenance of orientation during locomotion in unfamiliar environments is accomplished was investigated by having subjects walk behind a moving light line (1.12 m/sec) in a dark room and, from a stopping point, numerically estimate direction and distance to the starting point. Two linear distances (5.0–8.4 m) and the angle of direction change (45, 90, and 135 deg) were orthogonally varied as 12 locomotion patterns. Eight high-school students were assigned to each of three conditions, two in which the starting point was invisible, one in which it was visible. In one of the former conditions the subjects counted backwards rapidly during walking. Lower accuracy and longer latency times were found in the counting condition whilst the other two conditions differed only slightly. The results suggested that accurate maintenance of orientation is achieved by recurrent encoding, coordination and decoding of information about direction change and locomotion distance, processes which demand central processing capacity and therefore are interfered with by a concurrent task.  相似文献   
917.
918.
Normative data are presented for Southern black children on two objective personality inventories for children: the Missouri Children's Picture Series (MCPS), a child picture-sorting task, and the Missouri Children's Behavior Checklist (MBCL), a parent rating scale. The MCPS was administered to 615 black children attending public schools in a low socioeconomic area of the southeast United States. Parents returned the MBCL on 437 of the children. Means and standard deviations on eight MCPS personality scales and six MCBL behavior rating scales are presented for black males and females at ages 5 through 16, and effects of age, sex, and various scale intercorrelations are discussed. Results suggest systematic age and sex differences on the various scales for black children that are quite atypical when compared with the MCPS in other samples. Various empirical questions regarding the validity of these instruments when used with Southern black children are raised.  相似文献   
919.
Our study focused on the etiology of specific behavioral problems rather than on a global syndrome such as hyperactivity. As a first step in studying specific behavioral problems, we revised the Conners (1970) Parent Symptom Rating questionnaire to improve its factor structure. Our revised instrument and the testretest reliabilities of its 12 scales are described. A classical twin analysis comparing intraclass correlations for 54 pairs of identical twins and 33 pairs of same-sex fraternal twins indicated substantial genetic influence on behavioral problems in schoolaged children. We wish to express our gratitude for the Spencer Foundation's support of this research.  相似文献   
920.
Several studies of fact retrieval have shown that the more facts a person learns about a concept, the longer it takes him or her to retrieve any of these facts. This result has been interpreted to mean that retrieval of a fact about a concept involves a search of all facts stored in memory with that concept. In the present study, it is suggested that retrieval involves not an unfocused search of all facts stored with a concept, but rather a focused memory search that examines relevant stored facts and ignores irrelevant information. This argument is supported by three experiments in which subjects first learned simple facts (e.g., “The banker likes horses”) and then made speeded true-false decisions for test probes le.g., “The banker likes elephants”). Specifically, results suggest that facts stored with a concept may be organized into subsets. For example, a person’s knowledge about Richard Nixon might be organized into subsets concerning Nixon’s resignation, his trips to China, his family, and so on. The data further suggest that a person attempting to retrieve a fact about a concept (e.g., the name of Nixon’s wife) may simply decide which subset is most likely to contain the desired fact (e.g., the subset concerning Nixon’s family) and search that subset. If the sought-for fact is found in this subset, the search process terminates. If, however, the desired information is not located, other subsets of facts may be searched before the retrieval attempt is given up. The notion that memory search focuses on relevant stored facts and ignores irrelevant information may help to explain why experts (i.e., people who know a large number of facts about a topic) do not experience great difficulty in retrieving facts in their areas of expertise.  相似文献   
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