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991.
A. L. TITCHENER 《European Journal of Engineering Education》1989,14(2):167-173
This paper suggests chat engineering curricula should be designed on the basis that engineering is a vocation. It outlines how curricula might be developed by identifying engineering jobs and proceeding from job specification through engineering capability profiles to subjects of instruction. The need for manpower planning is stressed. Some problems related to small student numbers are outlined and some options offered for solution of such problems. 相似文献
992.
I Stewart L McNaughton P Davies S Tristram 《Research quarterly for exercise and sport》1990,61(1):80-84
It is known that an increased level of red blood cell 2,3-diphosphoglycerate (DPG) shifts the oxyhemoglobin dissociation curve to the right, thus allowing a greater unloading of oxygen at the tissue level. It has been hypothesized that phosphate might help increase VO2max by increasing 2,3-DPG level. Eight trained cyclists underwent three cycle ergometer tests (control, placebo, and experimental) to determine whether phosphate ingestion had any positive effect on VO2max, time to exhaustion, serum 2,3-DPG, and serum phosphate levels. We found no change between the control, placebo, or experimental conditions in pretest serum phosphate levels, but we did find increases in 2,3-DPG levels in the phosphate condition (p less than .05), which suggests that even a small amount of phosphate could increase levels of 2,3-DPG. We also found significant differences in VO2max between the control (p less than .05) and placebo (p less than .02) conditions and also in time to exhaustion between the three conditions (p less than .05). We suggest that phosphate may have an ergogenic effect, but clearly more work needs to be undertaken to ascertain the amount of phosphate required and the magnitude of the effect. 相似文献
993.
Raymond W. Kulhavy Mary T. White Bruce W. Topp Ann L. Chan James Adams 《Contemporary educational psychology》1985,10(3):285-291
College undergraduates read a 2400-word passage, responded to 16 multiple-choice questions, and received one of four types of feedback following their responses. Complexity of feedback was inversely related to both error correctability and criterion efficiency taken as a ratio of feedback study time to post-test corrects. The results were discussed in terms of depth of processing and instructional comprehension. 相似文献
994.
The present study evaluated the role of compatibility effects in the precuing of arm and direction parameters. In the first two experiments different stimulus and response arrangements were examined. For all three experiments the spatial precue and imperative stimuli were compatibly assigned to responses (i.e., a direct correspondence existed between the stimulus and response locations). Experiments 1 and 2 indirectly tested the effect of decision processes required by the stimulus-response set. Experiment 1 replicated previous research that has found longer reaction times for the direction uncertain parameter as compared to arm uncertain. Experiment 2 examined the precuing of arm and direction parameters with stimuli that maintained right-left arrangements for both parameters. Unlike Experiment 1, reaction times did not differ for precuing the two movement parameters. Experiment 3 directly examined the effect of differential decision requirements from up-down spatial stimuli and right-left spatial stimuli for a single parameter. In support of results from the first two experiments, results indicated longer reaction times for decisions from up-down stimuli as compared to right-left stimuli. Because reaction times for precued movement parameters are a function of the stimulus and response arrangements used, differences in reaction times are most likely due to compatibility effects arising from differences in the spatial arrangements of the precued stimulus and response set. 相似文献
995.
The purpose of this study was to use generalizability theory with both univariate and multivariate approaches to examine reliability of total body center of mass (CM) values calculated from cinematographical data. Twenty-eight college-aged male volunteers were filmed by a LOCAM camera at 100 fps while performing the basic locomotion skill of walking. Film analysis was conducted on each subject using six frames of film depicting a one-stride walking cycle consisting of right heel strike, right foot flat, left toe-off, left heel strike, left foot flat, and right toe-off. Nineteen segmental endpoints and a reference point were digitized by three experienced plotters. The digitizing sequence was replicated three times by each plotter. A FORTRAN program calculated nine CM values (three plotters by three repetitions) for each subject filmed in each of the six positions of the stride. The x- and y-coordinates of the CM values were the dependent variables analyzed by fully crossed 3-way univariate and multivariate ANOVAs (subjects by plotters by repetitions). All measurement facets were considered to be random. Results indicate that there was very little repetition error but considerable interplotter error for most frames. Phi-coefficients for x- and y-coordinates, separately, fluctuated across frames. The univariate values for the x-coordinates were similar but slightly less than the multivariate values. The Phi-coefficients for Y, however, were considerably lower than the multivariate values. The multivariate Phi-coefficients for generalizing over three plotters and three repetitions ranged from .82 to .90.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
996.
This paper considers the relationship between stress and cognitive functioning and discusses some of the concepts and methods that may be adopted to examine the relationship between stress and sports performance. It considers only that literature that may be relevant to, or furthers, the understanding of sports performance under competitive stress. One of the most popular approaches has been to explain the relationship in terms of the unidimensional inverted-U hypothesis. The validity of this approach to explaining sports performances in specific situations is discussed and it is generally concluded that the inverted-U hypothesis is too vague and simplistic. The discussion considers multidimensional approaches and discusses the suitability and implications of some more recent and more complex models of stress and performance which are now available in the psychological literature. It is concluded that the relationship between stress and sports performance is an extremely complex one and involves the interaction between the nature of the stressor, the cognitive demands of the task being performed and the psychological characteristics of the individuals performing it. 相似文献
997.
998.
V.L.Krupenin 《出版与印刷》2015,(1)
In this paper in general the dynamic effects are considered and described, caused by different stand-ing waves in discrete and distributed systems with impacts and other strongly positional non-linear fac-tors, introduction of which in the models of me-chanical objects is dictated by the necessity to con-sider processes, accompanied with impacts of me-chanical subsystems of different nature. 相似文献
999.
1000.