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21.
Thirty-one college undergraduates learned to touch abstract stimuli on a computer screen in arbitrarily designated “correct” sequential orders. Four sets of seven stimuli were used; the stimuli were arrayed horizontally on the screen in random sequences. A correct response (i.e., touching first the stimulus designated as first) resulted in that stimulus appearing near the top of the screen in its correct sequential position (left to right), and remaining there until the end of the trial. Incorrect responses (i.e., touching a stimulus out of sequence) terminated the trial. New trials displayed either the same sequence as the one on which an error had occurred (same-order correction procedure), or a new random sequence (new-order correction procedure). Whenever all responses occurred in the correct sequence, the next trial displayed a new random sequence. Each phase ended when five consecutive correct response sequences occurred. Initially, the same-order correction procedure increased control by the position as well as by the shape of the stimuli; also, it produced more errors, more total trials, more trials to mastery, and more individual patterns of reacquisition than were produced by the new-order procedure.  相似文献   
22.
Just noticeable differences in orientation are smaller at principal standard orientations than at oblique standard orientations when they are measured with the method of single stimuli. We determined whether this oblique effect is due to an anisotropy in decision factors. A first series of experiments showed that the subjects compare the stimulus with an internal criterion, and that this decision rule is used at all standard orientations. A second series of experiments determined the influence on the oblique effect of nonsensorial variables related to criterion setting. The results strongly suggest that the effect is not due to a criterial noise anisotropy and that criterion-setting processes are similar at principal and oblique standard orientations. The latter conclusion was also supported by an analysis of the sequential stimulus and response dependencies in this task. Hence, it appears that the oblique effect in line orientation discrimination, when it is measured with the method of single stimuli, is due not to decision factors but to a sensorially based anisotropy.  相似文献   
23.
Summary The effect of mental arithmetic (standard multiplication, with eyes closed) and eye-opening on the power spectral density of the EEG (recorded bipolarly from occipital and parietal regions) have been compared. The EEG was recorded on magnetic tape from normal subjects, (medical students) in a constant environment and subsequently analysed by an analogue computer (Noratom Instrument for Statistical Analysis and Computation, ISAC).Absolute measurements made from 15 subjects with eyes closed have shown that peaks of power at 10 Hz vary from 9 to 46 V2 per Hz. Qualitatively, suppression of power at 10 Hz is greater due to eye-opening than mental arithmetic.Analysis of pooled power spectral density functions from 11 subjects showed that the effect of eye-opening differed significantly from the effect of mental arithmetic at 2.5 and 12.5 Hz. Suppression of lower frequency alpha activity was more pronounced during calculation than during eye-opening. Compared with the eyes closed condition, eye-opening showed a highly significant suppression at 10 and 12.5 Hz (alpha activity) and from 15 to 25 Hz (beta activity). Mental arithmetic induced significant suppression at 7.5 and 10 Hz and from 15 to 30 Hz. Eye-opening enhanced lower frequency activity which calculation suppressed.Variation was greater between first, second and third calculations in pooled power spectral densities than between corresponding eye-opening epochs. It is suggested that these differences in effects of eye-opening and mental arithmetic reflect differences in underlying cerebral activity, rather than that an underlying factor common to both effects may be orbital in origin.  相似文献   
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The main purpose of this paper is to account for the varying analysis and formalisations of a same advertisement text, Mir Rose, by Jean Michel Adam. First, we draw the methodological frame of this psycholinguistic approach of composing and understanding-memorizing texts. We refer to the notions of prototypical textual schema, semantic macrostructure and superstructure. Then we point out the differences between argumentative text and argumentative discourse. Last, we try to explain why it has been possible for Adam to analyse and formalise the same text first as a narrative one and a few years later as an argumentative one. We suggest that his narrative approach is not specific and textual narrative means here temporal-causative sequence or problem solving, i.e., deeper and more general psychological devices than those involved in processing narrative text per se. From Toulmin and van Dijk approaches of argumentation, we propose our own analysis and formalisation of Mir Rose, the psychological validity or plausibility of which should be tested in experimental tasks of reading-memorising.
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27.
This study investigated the psychological and physical health status of 265 crew members on two U.S. Navy ships (a guided missile cruiser and a frigate on convoy escort duty for tankers under U.S. flag) during the Persian Gulf conflict at four time periods during combat-ready operations on a single day. Findings suggest that adaptation occurs to extreme stressors associated with sustained operations. Suggestions are made relative to measures that may minimize psychological and physical conditions that adversely affect performance under conditions of heavy stress. Report No. 89-18, supported by the Naval Medical Research and Development Command, Bethesda MD, Department of the Navy, under research Work Unit No. 63206N.M0096. The opinions expressed in this paper are those of the author and do not reflect the official policy or position of the Department of the Navy, Department of Defense, nor the U.S. Government.  相似文献   
28.
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   
29.
Medical expertise asa function of task difficulty   总被引:4,自引:0,他引:4  
This paper is concerned with factors that disrupt the pattern of forward reasoning characteristic of experts with accurate performance. Two experiments are described. In the first, the performances of cardiologists, psychiatrists, and surgeons in diagnostic explanation of a clinical problem in cardiology were examined. In the second, the performances of cardiologists and endocrinologists in diagnostic explanation of clinical problems within and outside their domains of expertise were examined. The performances of researchers and practicing physicians are also compared. The results of Experiment 1 replicated earlier results regarding the relationship between forward reasoning and accurate diagnosis. There were no differences in recall as a function of expertise. Experts did not show any bias toward using specific knowledge from their own areas of expertise. The results of Experiment 2 showed that the breakdown of forward reasoning was related to the structure of the task. In particular, nonsalient cues induced some backward reasoning even in subjects with accurate diagnoses. Some differences were also found between the types of explanation used by researchers and practitioners. The practitioners referred more to clinical components in their explanations, whereas the researchers focused more on the biomedical components.  相似文献   
30.
A total of 229 late adolescents (a large majority 15 to 19 years of age) completed a questionnaire that assesses a broad range of videogame-relevant experiences, preferences, and attitudes. Videogame playing was found to be a more popular, and a more highly regarded, activity among males than females. Gender differences were also found in participants' ratings of their motivations for playing videogames, their evaluations of particular characteristics of videogames, and their selection of their “most favorite” videogame. The differences between frequent and infrequent videogame players appeared to be limited to differences in the extent to which videogame playing is pursued and evaluated as a positive leisure activity, rather than reflecting broad differences in interest or personality. Some relations were found between participants' self-reported personality characteristics (i.e., self-esteem, empathy, conscientiousness, and introversion) and their attitudes toward videogames.  相似文献   
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