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81.
Abstract

This study investigated the effects of three types of recovery procedure on (a) circulatory recovery from a standardized bicycle ergometer exercise, (b) performance in a second standardized bicycle ergometer exercise, and (c) circulatory recovery from the second exercise. The recovery procedures were complete rest, light activity, and cold showers. Each of 10 male subjects underwent each recovery procedure on separate days. Analysis of variance for a randomized complete blocks design was used in the analysis of the data. Results indicated that cold showers decreased recovery heart rate after the first standardized exercise from 115 to 96 beats/minute and after the second exercise from 164 to 152 beats/ minute when compared with the other two conditions. Speed of performance in the second exercise was improved from 40.4 and 40.3 sec. in the case of rest and light activity to 38.9 sec. for cold showers. These improvements were all statistically significant at the .05 level. Three physiological explanations, not necessarily independent, are advanced: (a) local vasoconstriction of the skin vessels and vasodilatation of the muscle vessels causing a greater proportion of total blood flow to the working muscles, (b) establishment of a greater thermal gradient between the core and shell of the body allowing heat movement to the surface of the body by conduction between tissues rather than by skin blood flow, and (c) a decrease in sweat rate, thereby suppressing release of bradykinin, a vasodilator substance.  相似文献   
82.
Abstract

Sixty college men were tested on a new motor learning task: the foot-twist tracking task. They were given 35 one-min. trials; each consisted of 30 sec. of work followed by 30 sec. of rest. A 5-min. rest period was interpolated between trials 25 and 26 to allow for the dissipation of reactive inhibition accrued during prerest performance. The results supported the expectation that practice on the new task would result in significant amounts of learning. However, the improvement in performance, while fairly large (21%), is substantially less than that found on the pursuit rotor and other large muscle motor coordination tasks. The expectation of reliable learning scores is also supported by the present results (r = .77). This learning reliability is relatively high when compared with those obtained on other large muscle motor learning tasks.  相似文献   
83.
Abstract

It was the purpose of this investigation to conduct a program in perceptual-motor development and to determine changes in, and assess relationships between, changes in perceptual-motor development on visual perception and reading readiness of first-grade children. Four classes were equated on the variables age, height, sex, and weight. Two of the classes (experimental) were exposed to the perceptual-motor program for 12 weeks and the other two classes (control) took part in the conventional physical education program. All students participated in their regular classroom activities. All subjects were evaluated in perceptual-motor development, visual perception, and reading readiness prior to and immediately following the research program. The difference scores (pre- and post-test) were evaluated by two-way ANOVA to determine if there were any significant differences between groups. F ratios for the three variables tested were all significant beyond the .01 level in support of the perceptual-motor program.  相似文献   
84.
Abstract

The purpose of the study was to determine the effects of 15, 30, and 45 min of conditioning on maximum performance and cardiorespiratory fitness variables, body composition, pulmonary function, and serum lipids. Subjects, ages 20 to 35, were 59 inmates at a California state prison. The conditioning included running and walking and was performed three days/week at approximately 85 to 90% max HR for 20 weeks. The distance covered per exercise session was approximately 1.75, 3.25, and 5.1 miles for the 15-, 30-, and 45-min groups, respectively.

Improvements in treadmill performance time. [Vdot]O2 max, max O2 pulse, diastolic blood pressure, and total skinfold fat were proportional to duration of the training session; i.e., the subjects training in the longer duration sessions showed the greater improvements. The control group showed no significant change during the same period. Compared to the control group, the 15-min group made significant reductions in resting HR, total skinfold fat, percent fat, and waist girth and increases in [Vdot]O2 max, max O2 pulse,[Vdot]E max, and treadmill performance time. Vital capacity, FEV1.0, and % FEV1.0 remained relatively unchanged in all four groups, as did serum cholesterol and triglycerides. The 45-min group improved significantly more than the 15-min group in treadmill time, [Vdot]O2 max, max O2 pulse, resting systolic and diastolic blood pressures, and percent fat. In general, comparisons between the 15- and 30-min groups and between the 30- and 45-min groups failed to yield statistically significant differences.  相似文献   
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89.
Retrospective perceptions and causal beliefs regarding the temporal patterning of precompetitive psychological responses were examined in 12 elite rugby union players. Composite sequence analysis resulted in a series of temporal networks to describe participants' cognitive, affective, and behavioural responses in a time-to-event paradigm. Match-related cognitions remained stable in the lead up to competition, while perceptions of physical symptoms peaked at the onset of performance. Affective responses were associated with feelings of anxiety and tension in the early temporal phases but excitement, confidence, and efficacy in team-mates directly before competition. Behavioural themes described activities associated with technical and physical preparation, familiarization with environmental conditions, and strategies to control activation states early on or directly before competition. The findings highlight the idiosyncratic and dynamic nature of the temporal patterning of precompetitive responses and the influence that perceptions of the team have upon individual preparation for performance. Implications are discussed in the context of the type and timing of intervention for developing individual and team preparatory routines.  相似文献   
90.
The aim of this study was to determine pedometry steps per minute (SPM) cutscores that accurately quantify physical activity (PA) time in first- through fourth-grade physical education. A total of 257 participants were grouped in two data pools, first- and second-grade (n = 126), and third- and fourth-grade (n = 131). Systematic observation was the PA criterion instrument and pedometry was the predictor instrument. Correlations between physical activity measures were strong (r = .82-.89, p < .01). Ten min of PA and 33.33% of the lesson time engaged in PA within a 30-min class can be quantified by 61-63 SPM for first- and second-grade, and 58-61 SPM for third- and fourth-grade. IN CONCOLUSION: (a) SPM values were a valid indicator of students achieving or not achieving PA criteria, and (b) pedometry is a valid and practical tool for physical activity surveillance within physical education.  相似文献   
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