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951.
Reaction and movement times in men of different ages: a population study   总被引:5,自引:0,他引:5  
Tests of psychomotor and motor speed at different levels of complexity were studied in random samples of men aged 31 to 35, 51 to 55, and 71 to 75 yr. The study was performed as a part of a larger research project on health and functional aging. Analyses indicated significantly slower responses among older men at all levels of test complexity (maximal knee extension velocity, tapping rate, simple and choice reaction and movement times). There were marked differences both between the youngest and the middle-aged groups and between the middle-aged and the oldest groups. Within the age groups high psychomotor and motor speed were associated with a favourable functioning of certain senses (vibration sensitivity and postural balance), with a high isometric muscular force, and with a high directly assessed aerobic capacity. The most important covariants of the speed functions within the age groups were, however, cognitive performance, length of education, and perceived health.  相似文献   
952.
Movement rates of formant frequencies and the extents of articulatory change were spectrographically analyzed in the fLuent (VCV) utterances of 20 stutterers and nonstutterers. The velocities of articulator movement throughout the first vowel and velocities into the second vowel were not significantly different for the two groups. These mean rates of movement, although nonsignificant, were slower in stutterers and slightly more variable, and the extent of articulator movement was comparable. These results do not support the contentions that stutterers use coarticulatory movements that are too rapid or that stutterers have a poorer competence for rapid coordination of speech movements. The rationales of rate-control treatment methods to slow coarticulatory movements in stutterers need to be reexamined.  相似文献   
953.
Taste sensitivity for sodium chloride in solution and sensitivity and preference for sodium chloride in bread were measured in 14 male patients undergoing hemodialysis. There was an increase in sensitivity to salt taste following dialysis only when assessed using the bread samples. Patients on a lower sodium diet were more sensitive to salt taste in bread. Although the taste changes were not related to the decreases in serum sodium or to copper, greater increases in sensitivity were related to greater increases in serum zinc during dialysis.  相似文献   
954.
Timecourse of coactivation in bimodal divided attention   总被引:7,自引:0,他引:7  
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955.
Aerobic exercise which resulted in a significant improvement in cardiovascular functioning had no more effect on psychological mood states than did the placebo control of participation in nonaerobic recreational games or no exercise and sport at all (N = 430 college students). Beta-endorphin levels with the 41 depressed subjects were not a biochemical link that might explain the possible influence of physical activity on depression.  相似文献   
956.
The performance of 81 gifted elementary students on the Visual Aural Digit Span test is discussed. The students generally showed advanced performance from Grade 1 through Grade 5 and from age 7-0 yr. through 11-11 yr. Performance at Grade 6 and the 12-0 to 12-11-yr.-old levels were generally at age-expected levels and were probably restricted due to the test's limited ceiling. Tables of means across grade and age and needs for further research are also presented.  相似文献   
957.
Bandler and Grinder's hypothesis that eye-movements reflect sensory processing was examined. 28 volunteers first memorized and then recalled visual, auditory, and kinesthetic stimuli. Changes in eye-positions during recall were videotaped and categorized by two raters into positions hypothesized by Bandler and Grinder's model to represent visual, auditory, and kinesthetic recall. Planned contrast analyses suggested that visual stimulus items, when recalled, elicited significantly more upward eye-positions and stares than auditory and kinesthetic items. Auditory and kinesthetic items, however, did not elicit more changes in eye-position hypothesized by the model to represent auditory and kinesthetic recall, respectively.  相似文献   
958.
For 40 males who smoked 20 cigarettes a day titratable acidity of the urine was significantly correlated with nicotine/cotinine excretion at several sample intervals, as was urinary pH, but not urinary acidity and daily cigarette consumption or serum COHB.  相似文献   
959.
The parallel-lines illusion provides a prototypical example of visual-size assimilation, where the size of a test element is phenomenally skewed towards (or "averaged with") that of a context element. Most assimilation theories predict that distortion should decrease with spatial separation between context and test lengths. However, there is some disagreement about the nature of the function relating sizes of context and test elements and magnitude of assimilation. The present study tests the limits of assimilation in the parallel-lines configurations by observing the effects of a wide range of context/test size ratios, repeated over two disparate levels of spatial separation. The results replicate and extend 1979 findings by Brigell and Uhlarik, confirming that assimilation rises to a peak at midrange size ratios, only to decrease continuously as the ratios become more extreme. The functions were nonmonotonic and similar in shape for both levels of spatial separation, with an over-all decrease in distortion for configurations with the larger separation.  相似文献   
960.
Children's perception of parental exercise: influence of sex and age   总被引:1,自引:0,他引:1  
The purpose of the study was to document children's perception of parental exercise, relating these perceptions to (1) the self-reported parents' habits of exercise, and (2) the children's own activity patterns. The subjects were 198 students of both sexes, aged 12 to 14 yr. and enrolled in school Grades 7 to 9. A standard questionnaire assessed their perceptions of parental and personal physical activity. Both parents of each subject also reported their respective levels of habitual physical activity. Congruence between the children's perceptions and the self-reported exercise habits of the opposite-sex parent differed for boys and girls, increasing for boys and decreasing for girls between Grades 7 and 9. No significant associations were observed between the children's perception of parental exercise patterns and their own like habits. This suggests that during adolescence parental influences are minimized by other factors, personal or environmental.  相似文献   
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