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81.
An invisible displacement test was administered to cats in order to test the hypothesis that search behaviour in this species is influenced by their limited capacity for object permanence as well as by their previous experience with the environment. Experiment 1 compared three groups of cats in a five-choice hiding task in which the hiding places could be discriminated by their spatial positions. Two groups received a visible displacement training before the invisible displacement test and one group did not. Experiment 2 compared two groups of trained subjects in the same task, but the hiding places could be discriminated by spatial and visual cues. The results confirmed that cats are unable to solve problems with invisible displacements. The visible displacement training improved their performance, but was not sufficient to make them succeed. Experience with the hiding potential of the covers also gives more persistence to search behaviour. Finally, the distribution of search attempts is not determined by the proximity to the target and is influenced only partially by the subjects' previous experience. Like Stage 5 infants, cats rely mainly on their immediate perception. They search for an object in the last location they have seen it disappear or under the nearest cover from this location.  相似文献   
82.
The interrelationships between cigarette, alcohol, and coffee use were examined in 307 U.S. army trainees and 304 U.S. enlisted army personnel. Usage patterns indicated distinct gender differences in this occupational setting. Among women, cigarette use and alcohol consumption were positively correlated; whereas for men, cigarette and coffee use were positively related. For both males and females, alcohol and coffee use were only weakly correlated. As demonstrated in other studies, nonsmokers showed a consistent pattern of abstention from coffee and alcohol or moderate alcohol use.  相似文献   
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The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.  相似文献   
85.
Tested a 7-month, media-based, community intervention among Hispanics in San Francisco designed to change levels of information on the damaging effects of cigarette smoking and on the availability of culturally appropriate cessation services. Three community-wide surveys of Hispanics were conducted with independent random samples, two as baselines (n = 1,660 and 2,053) and one postintervention (n = 1,965). Results showed that changes in the level of awareness of cessation services had taken place after implementation of the intervention. Furthermore, those changes took place primarily among the less acculturated Spanish-speaking Hispanics who were the target of the intervention. The changes in information reported here demonstrate that a culturally appropriate information dissemination campaign that utilizes multiple channels can produce changes in a community's level of information even when the campaign is implemented for a relatively short period.  相似文献   
86.
How is meaning assigned to those terms in a theory which are remote from direct observational instantiation? Models and analogies play a role, but close examination of theories in high energy physics shows that the design of experimental apparatus also influences the interpretation of such terms. Certain apparatus favours certain kinds of effects, and this affects the way mathematical theories are interpreted. In particular track producing apparatus becomes involved with theories in which photonic terms are picked out in the theory. A further conceptual constraint is thus introduced. It is argued that this situation favours the interpretation of dispositional properties as affordances rather than as simple dispositions.  相似文献   
87.
The role accorded to the public by scientists and philosophers of science has undergone an essential historical change in the last three centuries. Public participation in (witnessing of) scientific experiments was considered an important requirement for 17th century experimenters (e.g. for Boyle or Pascal). The cognitive role played by lay persons was later substantially downgraded; witnessing went out of fashion, while science became more and more esoteric and a matter for experts only. Part of this process was that all scientific disciplines became intensively compartmentalized and in consequence a rather puzzling or even paradoxical situation appeared: that the scientists themselves were and are being reduced epistemically to the status of lay persons, outside of their proper field of expertise (as was pointed out by J. Hardwig). The paper deals with some cognitive aspects of this historical process.  相似文献   
88.
Summary Young and elderly adults acquired route information from a sequence of slides depicting a walk through an actual environment. The accuracy of their distance knowledge after viewing the slides was compared for a normal presentation and a presentation with temporospatial discontinuity. No differences between age groups were noted under normal presentation conditions, but young adults were more accurate under conditions of temporospatial discontinuity. Results were interpreted in terms of an age-related decrement in the operational capacity of working memory. They were also viewed as supportive of a constructivist-representational theory of spatial learning.This research was conducted while the senior author served as Principal Investigator for National Institute on Aging Grant No. 1 ROI AG05169, Aging and Spatial Cognition, sponsored by the National Institutes of Health, Bethesda, MD, USA  相似文献   
89.
Hispanics in Ivy: Assessing identity and perceived threat   总被引:1,自引:0,他引:1  
Kathleen Ethier  Kay Deaux 《Sex roles》1990,22(7-8):427-440
Membership in social groups is an important aspect of the self-concept, as a number of theorists such as Tajfel (1981) have recognized, and ethnic identity is a major exemplar of such groupings. In the present research, we focus on the particular case of Hispanic identity and the degree to which that identity may be threatened for first-year Hispanic students who enter a predominantly Anglo university. Forty-five Hispanic students (17 female, 28 male) at two Ivy League universities were interviewed early in their first year to assess Hispanic identity, collective self-esteem (Luhtanen & Crocker, 1988), and perceived threats to Hispanic identity. In addition, we considered the degree to which strength of cultural background relates to self-esteem and to perceptions of threat. The majority of students claimed Hispanic as an important identity. Strength of cultural background generally acted as a buffer to perceived threat, particularly for men. Cultural background was also related to collective self-esteem for men but not for women, even though Hispanic identity was more important for women than men. The results attest to the importance of both gender and ethnicity to self-definition and self-esteem, as well as to the complexity of the relationships among these variables.We thank Tracey Revenson as well as the members of the Identity Research Seminar at the CUNY Graduate Center for their comments on an earlier version of this paper.  相似文献   
90.
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