首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1828篇
  免费   17篇
  国内免费   2篇
教育   1256篇
科学研究   214篇
各国文化   27篇
体育   124篇
综合类   2篇
文化理论   41篇
信息传播   183篇
  2021年   14篇
  2020年   17篇
  2019年   31篇
  2018年   50篇
  2017年   47篇
  2016年   30篇
  2015年   22篇
  2014年   22篇
  2013年   506篇
  2012年   26篇
  2011年   41篇
  2010年   30篇
  2009年   46篇
  2008年   38篇
  2007年   39篇
  2006年   25篇
  2005年   25篇
  2004年   29篇
  2003年   19篇
  2002年   23篇
  2001年   24篇
  2000年   19篇
  1999年   21篇
  1998年   19篇
  1997年   13篇
  1996年   26篇
  1995年   23篇
  1994年   26篇
  1993年   29篇
  1992年   21篇
  1991年   18篇
  1990年   19篇
  1989年   16篇
  1988年   18篇
  1987年   19篇
  1986年   24篇
  1985年   19篇
  1984年   14篇
  1983年   15篇
  1982年   19篇
  1981年   17篇
  1980年   19篇
  1979年   18篇
  1978年   15篇
  1977年   19篇
  1976年   19篇
  1975年   12篇
  1974年   19篇
  1973年   16篇
  1968年   10篇
排序方式: 共有1847条查询结果,搜索用时 843 毫秒
91.
American students participating in a study abroad program in Switzerland were studied over a three-year period (1968–1970) using the methods of participant observation and written questionnaires. The researcher developed a typology of five unique types of student adaptation. From this typology recommendations are made to increase the educational impact of study abroad on participants.  相似文献   
92.
In this holistic review of cycling science, the objectives are: (1) to identify the various human and environmental factors that influence cycling power output and velocity; (2) to discuss, with the aid of a schematic model, the often complex interrelationships between these factors; and (3) to suggest future directions for research to help clarify how cycling performance can be optimized, given different race disciplines, environments and riders. Most successful cyclists, irrespective of the race discipline, have a high maximal aerobic power output measured from an incremental test, and an ability to work at relatively high power outputs for long periods. The relationship between these characteristics and inherent physiological factors such as muscle capilliarization and muscle fibre type is complicated by inter-individual differences in selecting cadence for different race conditions. More research is needed on high-class professional riders, since they probably represent the pinnacle of natural selection for, and physiological adaptation to, endurance exercise. Recent advances in mathematical modelling and bicycle-mounted strain gauges, which can measure power directly in races, are starting to help unravel the interrelationships between the various resistive forces on the bicycle (e.g. air and rolling resistance, gravity). Interventions on rider position to optimize aerodynamics should also consider the impact on power output of the rider. All-terrain bicycle (ATB) racing is a neglected discipline in terms of the characterization of power outputs in race conditions and the modelling of the effects of the different design of bicycle frame and components on the magnitude of resistive forces. A direct application of mathematical models of cycling velocity has been in identifying optimal pacing strategies for different race conditions. Such data should, nevertheless, be considered alongside physiological optimization of power output in a race. An even distribution of power output is both physiologically and biophysically optimal for longer ( > 4 km) time-trials held in conditions of unvarying wind and gradient. For shorter races (e.g. a 1 km time-trial), an 'all out' effort from the start is advised to 'save' time during the initial phase that contributes most to total race time and to optimize the contribution of kinetic energy to race velocity. From a biophysical standpoint, the optimum pacing strategy for road time-trials may involve increasing power in headwinds and uphill sections and decreasing power in tailwinds and when travelling downhill. More research, using models and direct power measurement, is needed to elucidate fully how much such a pacing strategy might save time in a real race and how much a variable power output can be tolerated by a rider. The cyclist's diet is a multifactorial issue in itself and many researchers have tried to examine aspects of cycling nutrition (e.g. timing, amount, composition) in isolation. Only recently have researchers attempted to analyse interrelationships between dietary factors (e.g. the link between pre-race and in-race dietary effects on performance). The thermal environment is a mediating factor in choice of diet, since there may be competing interests of replacing lost fluid and depleted glycogen during and after a race. Given the prevalence of stage racing in professional cycling, more research into the influence of nutrition on repeated bouts of exercise performance and training is required.  相似文献   
93.
The purpose of this study was to determine the influence of beliefs about gender appropriateness and conceptions of ability on perceived and actual competene and patterns of behavior during practice of the hockey wrist shot. Sixty-eight undergraduate women formed four treatment conditions based on their beliefs about gender appropriateness and conceptions of ability. Four teachers taught across the treatment conditions for a total of 16 learning groups. Data were collected through a three-part questionnaire and from audio-video taping of the entire episode to ascertain the paticipants' competency beliefs, effort, and performance. Gender appropriateness impacted the participants' perceptions of competence and actual performance in the study, while beliefs about conceptions of ability did not produce a significant difference. This study reaffirms that educators must work diligently to combat the stereotypical beliefs many hold with respect to the gender appropriateness of physical activities.  相似文献   
94.
95.
96.
Rightsholders' groups have given CLA approval to develop sector-by-sector licences for the digitisation of existing print material. The first two licences, for pharmaceutical regulatory submissions and for higher education, are approaching completion. Rightsholders will be asked to opt-in to each of them and to determine applicable fees for each of their publications.  相似文献   
97.
98.
99.
100.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号