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Two studies tested the effects of TV ads with celebrity endorsement on the product preference and understanding of 8- to 14-year-old boys. Study 1 compared two ads for a model racer. One had celebrity endorsement (by a famous race driver) and footage of real automobile racing featuring the celebrity (live action); the second had neither feature. Study 2 employed one ad for a different brand of model racer edited to generate a 2 (endorser presence) by 2 (inclusion of live racetrack action) factorial design. A total of 415 boys were exposed to one of the experimental ads or a control ad, embedded in a new animated children's adventure program. Preference for the advertised brand of model racer (pre- and postviewing) and a number of cognitive variables were assessed. Exposure to endorsement led to increased preference for the toy and belief that the celebrity was expert about the toy. Live action led to exaggerated estimates of the physical properties of the toy and the belief that the ad was not staged. The 8- to 10-year-olds associated the glamour of the endorser with the toy and were more reliant on his advice than were 11- to 14-year-olds. However, the two age groups were not differentially affected by the ads. Contrary to the speculation of many researchers, understanding about advertising intent and techniques and cynicism about ads had almost no influence on product preference after viewing.  相似文献   
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This article presents a series of studies investigating the influence of experimental factors and the personological variables of age and sex upon spatial abilities. It was hypothesized that the overall equivocal findings typical of spatial research may be partially due to the use of different factors across studies. The experimental variables of spatial factor, task demands, spatial information type, information-processing mode, and response mode were systematically manipulated across the eight studies. In each individual analysis of data collected in a specific study, no significant main effect sex differences were detected. However, when a meta-analytic review of the studies was conducted, both spatial information dimensionality and information dimensionality × spatial factor assessed proved to be influential on male and female spatial performances. Female performance was superior when the dimensionality of stimulus and response variables was invariant. Males had the advantage when dimensionality crossing was necessitated. The discrepancy between the sexes was particularly dramatic when the spatial orientation factor was tapped.  相似文献   
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Research is reviewed which suggests that hyperventilation syndrome is an underdiagnosed disorder for the presentation of many patients experiencing apparent anxiety states. In a test of this hypothesis, 21 normal individuals (9 female) underwent a 2 min period of intentional hyperventilation following a 10 min baseline phase. Hyperventilation was accompanied by increased subjective anxiety and tachycardia, and indications of peripheral vasoconstriction. Following hyperventilation, Ss experienced increased levels of state anxiety and perceived autonomic arousal, as indexed by self-report instruments. These results support the hypothesis that undiagnosed hyperventilatory phenomena may be etiologically implicated in states of pathologic anxiety.  相似文献   
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African Americans are at significantly greater risk of hypertension and worse cardiovascular outcomes than other racialized groups, yet hypertension intervention effects remain limited. Thus, it is necessary to understand the potential mechanisms whereby interventions may be more effectively targeted to improve health. Supported by prior research evidence and guided by the Biobehavioral Family Model, this study examined associations between family relationship quality, psychological wellbeing, and self-management behaviors for African Americans with hypertension. Data were pooled from three Midlife Development in the U.S. projects, resulting in a sample of 317 African Americans (63.4% female, Mage = 53.32) with self-reported high blood pressure in the past 12 months. We tested four cross-sectional multiple mediator models, with depressed mood and environmental mastery mediating associations between family strain and exercise, smoking, problematic alcohol use, and stress-eating. Environmental mastery mediated the association between greater family strain and decreased odds of achieving recommended exercise levels; greater odds of reporting problematic alcohol use; and greater stress-eating. Though family strain was associated with depressed mood in each model, this variable did not serve as an indirect pathway to self-management behaviors. Family strain, and the potential pathway identified via environmental mastery, may be a meaningful predictor of disease self-management for African Americans with hypertension. Longitudinal studies are needed to examine directionality and to support intervention trials for improving self-management and hypertension outcomes.  相似文献   
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This three-part study describes wavelength generalization gradients around a series of training wavelengths ranging from 480 to 645 om. Luminance was controlled for the pigeon’s spectral sensitivity. The response measure was probability of keypecking during a 2-sec stimulus presentation. Both an extinction procedure, where stimulus wavelengths occurred in 15-nm steps, and a maintained discrimination procedure, where step size was 2 to 4 nm, were used to obtain gradients. During a portion of the maintained discrimination procedure, new luminances were introduced, so that the effect of luminance level on gradient slope could be examined. Comparison of the resulting functions across training wavelengths revealed: (1) consistent differences in gradient slope in different spectral regions and (2) an increase in slope with luminance increase. The findings are related to recent electroretinographic wavelength contrast data and to psychophysical measures of wavelength discriminability.  相似文献   
49.
von W right J. M. Free recall of repeated words as a function of intralist variability. Scand. J. Psychol ., 1972, 13 , 39–42.—Five "critical" words were repeated 4 times each in constant positions within lists of 80 items. The number of different filler words, and the order of the repeated filler words, was varied between lists. In free recall tests total recall was approximately constant, but the recall of the critical words was significantly better the greater the variation in the intralist context of these words, especially the greater the number of different filler words. The results are interpreted in terms of the encoding variability hypothesis.  相似文献   
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