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911.
E K Warrington  M James 《Perception》1986,15(3):355-366
An investigation is reported of the ability of normal subjects and patients with right-hemisphere lesions to identify 3-D shadow images of common objects from different viewpoints. Object recognition thresholds were measured in terms of angle of rotation (through the horizontal or vertical axis) required for correct identification. Effects of axial rotation were very variable and no evidence was found of a typical recognition threshold function relating angle of view to object identification. Although the right-hemisphere-lesion group was consistently and significantly worse than the control group, no qualitative differences between the groups were observed. The findings are discussed in relation to Marr's theory that the geometry of a 3-D shape is derived from axial information, and it is argued that the data reported are more consistent with a distinctive-features model of object recognition.  相似文献   
912.
Summary Human observers can selectively allocate processing resources to different areas of the visual field within a single fixation. This spatial attention system may affect either the quality of information extraction or the decisions and responses based on this information. This paper reviews evidence from behavioral, single-unit, and event-related potential paradigms; the evidence suggests a relatively early locus of spatial attention.This research was supported by the U. S. Army Research Office under contract DAAG 29-83-K-0049. Portions of this paper were presented to the Conference on Attention and Action, Bielefeld, West Germany, in July 1985  相似文献   
913.
Sex difference trends in completed suicide   总被引:1,自引:0,他引:1  
The recent suicide literature increasingly has contained statements suggesting that the differences in completed suicide between the sexes are lessening. A compilation of official suicide data for 1933-1980 verifies such a trend from the 1950s through 1971. However, increased differences (as measured by the ratio of male to female rates) were consistently observed from 1971 to 1980. These trends were found for data for the nation, for whites and nonwhites, for numbers of suicides, for crude rates, and for age-adjusted rates. Decreased sex differences were obtained for those 35-44, 45-54, 55-64, and for 65+ years of age, but increased sex differences were observed for those aged 15-24 and 25-34. Possible explanations for these findings are presented.  相似文献   
914.
Younger adult students between 19 and 24 years of age (M = 21.3 years), older adult students between 61 and 76 years of age (M = 67.9 years), and older adult nonstudents between 62 and 76 years of age (M = 68.5 years) were assessed for health (self-ratings of physical and mental health), social functioning (self-ratings of physical and mental activity, perceived role activity level, perceived roles, locus of control, and age-norm expectations), and cognitive functioning (Wechsler Adult Intelligence Scale-Revised vocabulary and block design, and paired associate memory). Age differences were observed in self-ratings of health, social roles, intellectual performance, and memory. No student status differences were observed. The results are discussed in terms of plasticity of intellectual function and characteristics of student status in later adulthood.  相似文献   
915.
Speech processing involves rapid decoding and construction of meaning from a transitory acoustic signal. Because older adults have been found to be slower in performing many cognitive tasks, we hypothesized that they may have difficulty in immediate recall for speech of increasing input rate. Two experiments are reported in which both older and younger participants listened to and immediately recalled sentences that were systematically varied in speech rate and number of propositions. Although recall performance of the older adults showed a disproportionate decline when speech rate was increased, older adults, as well as the younger adults, were able to recall sentences of increasing propositional densities. We also found that the tendency to recall a greater proportion of main ideas than details (the levels effect) was enhanced by increased propositional density, and depressed by increased speech rate and increased age. These results are discussed in terms of an age-related change in the rate at which information can be processed in working memory.  相似文献   
916.
Fluid intelligence belongs to that cluster of intellectual abilities evincing aging loss. To examine further the range of intellectual reserve available to aging individuals and the question of replicability in a new cultural and laboratory setting, 204 healthy older adults (mean age = 72 years; range = 60-86) participated in a short-term longitudinal training study. For experimental subjects, 10 sessions consisted of cognitive training involving two subability tests (Figural Relations, Induction) of fluid intelligence. The pattern of outcomes replicates and expands on earlier studies. Older adults have the reserve to evince substantial increases in levels of performance in fluid intelligence tests. Transfer of training, however, is narrow in scope. Training also increases accuracy of performance and the ability to solve more difficult test items. Difficulty level was estimated in a separate study, with a comparable sample of N = 112 elderly adults. Future research is suggested to examine whether intellectual reserve extends to near-maximum levels of performance.  相似文献   
917.
When presented with a behavioral problem or symptom expression that involves two systems, such as a serious school-related problem, the therapist needs to design an approach that will intervene effectively and expeditiously in both systems. This paper offers a guide to stages of problem escalation and therapeutic intervention that is intended to aid the problem-solver's thinking processes in approaching a troubled situation that involves two systems, the school and the home.  相似文献   
918.
Book reviews     
With Faith and Fury. Delos McKown. New York: Promethius Books, 1985. pp 440. $16.95

The Sacred in a Secular Age. Phillip E. Hammond, Editor. University of California Press, 379 pages (p/b) $8.95 (£8.50)  相似文献   

919.
920.
The purpose of the present experiment was to investigate the efficacy of a goal orientation procedure in their treatment of apathy, isolation, and insufficient goal setting skills in chronic psychiatric residents. The experiment was conducted in a behaviorally-oriented deinstitutionalization program in a state psychiatric hospital. Three male and four female chronic psychiatric residents served as research participants. A group repeated measures design with four within-participant phases (ABA‘B’) was utilized. The goal orientation procedure included a written schedule that was completed by each research participant daily. This Daily Living Schedule required that a behavior be specified by the participant for every half-hour period during the day (8:30 a.m. to 9:00 p.m.). During all four phases of the experiment, research participants were observed on the ward from 8:30 a.m. to 12:00 noon and 1:00 p.m. to 5:00 p.m. for engagement in scheduled target behaviors. The daily scheduling procedure produced substantial increases in appropriate behavior such as social activities, ward jobs, and participation in treatment programs, whereas decrease were produced in inappropriate behavior such as isolation and day time sleeping.  相似文献   
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