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41.
Charles Oppenheim Huw Alexander Charles Oppenheim Cliff Morgan 《Learned Publishing》2007,20(2):156-158
Open Access: Key Strategic, Technical and Economic Aspects Edited by Neil Jacobs Chandos Publishing, 2006. 250 pp. ISBN 1‐84334‐203‐0, £39.95, pbk ISBN 1‐84334‐204‐9, £57.00, hbk Selling Rights, 5th edn Lynette Owen Routledge, 2006. 384 pp. ISBN 978‐0‐415‐36280‐1, £75.00 hbk ISBN 978‐0‐415‐38652‐4, £29.95 pbk Bound by Law? Tales from the Public Domain by Keith Aoki, James Boyle and Jennifer Jenkins Duke Law School Center for the Study of the Public Domain, 2006. 76 pp. ISBN 0‐974‐15531‐4, $5.95, pbk. Freely available online at http://www.law.duke.edu/cspd Digital Preservation Marilyn Deegan Simon Tanner Facet Publishing, 2006, Digital Futures Series. 288 pp. ISBN 978‐1‐85604‐485‐1, £39.95, hbk. 相似文献
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Athens sits in a basin approximately 450 km2 in area, surrounded by mountains and open sea. Anthropogenic emissions in conjunction with the topographical and meteorological conditions can result in high air pollution within the city. The pollutants of concern for athletes competing in Athens 2004 appear to be nitrogen dioxide (NO2), ozone and particulate (PM10) pollution. Exposure to elevated ozone concentrations has been reported to give rise to symptoms that include cough, chest pain, difficulty in breathing, headache, eye irritation and a decrease in forced expiratory volume in one second. All of these effects are likely to impact upon performance, and several studies of cyclists suggest this to be the case. In contrast, the impact of ambient concentrations of NO2 appears to be negligible on normal activities, but at high exercise intensities the impact remains unclear. The use of currently available information and models to predict the effect of ozone and other pollutants on elite athletes is problematical, since such models are based upon significantly lower ventilation rates than those achieved by some elite athletes. In addition, it is already known that the response to ozone can vary somewhat between individuals. Since the individuals who will be competing in Athens are physiologically very different to the participants in most published studies, it is difficult to predict individual responses. There is some evidence to indicate that adaptation to the adverse health and performance effects of ozone can occur, so that performance is partially recovered on re-exposure. The adaptation is not seen in all studies and appears to be dependent on several factors, including the initial sensitivity of the individual to ozone. Antioxidant supplementation has also been shown in some studies to partially ameliorate the adverse effects of ozone by counteracting the oxidative stress mechanism associated with this pollutant. Whether this transfers to performance enhancement per se remains unclear at present. Additional research is required to gain a sound understanding of the effects of a complex mixed air pollution exposure on the pulmonary function and performance of athletes exercising at high work intensities. 相似文献
43.
Larsen GE George JD Alexander JL Fellingham GW Aldana SG Parcell AC 《Research quarterly for exercise and sport》2002,73(1):66-72
The purpose of this study was to develop a submaximal, 1.5-mile endurance test for college-aged students using walking, jogging, or running exercise. College students (N = 101: 52 men, 47 women), ages 18-26years, successfully completed the 1.5-mile test twice, and a maximal graded exercise test. Participants were instructed to achieve a "somewhat hard" exercise intensity (rating of perceived exertion = 13) and maintain a steady pace throughout each 1.5-mile test. Multiple linear regression generated the following prediction equation: VO2 max = 65.404 + 7.707 x gender (1 = male; 0 =female) - 0.159 x body mass (kg) - 0.843 x elapsed exercise time (min; walking, jogging orrunning). This equation shows acceptable validity (R = .86, SEE = 3.37 ml x kg(-1) min(-1)) similar to the accuracy of comparable field tests, and reliability (ICC = .93) is also comparable to similar models. The statistical shrinkage is minimal (R(press) = 0.85, SEE(press) = 3.51 ml x kg(-) x min(-1)); hence, it should provide comparable results when applied to other similar samples. A regression model (R =.90, and SEE = 2.87 ml x kg(-1) min(-1)) including exercise heart rate was also developed: VO2 max = 100.162 +/- 7.301 x gender(1 = male; 0 =female) - 0.164 x body mass (kg) - 1.273 x elapsed exercise time -0.156 x exercise heart rate, for those who have access to electronic heart rate monitors. This submaximal 1.5-mile test accurately predicts maximal oxygen uptake (VO2max) without measuring heart rate and is similar to the 1.5-mile run in that it allowsfor mass testing and requires only a flat, measured distance and a stopwatch. Further, it can accommodate a wide range of fitness levels (from walkers to runners). 相似文献
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This paper describes a small‐scale study of what the authors describe as the ecosystemic approach to changing chronic problem behaviour. The study was undertaken with a group of twelve Leicestershire primary teachers. The technique is briefly described and then teachers' responses to it and its effectiveness are discussed. Four case study examples are presented and finally its potential is considered. Although in this case the work was undertaken with primary teachers, this is an approach which could also be useful at secondary level. 相似文献
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