全文获取类型
收费全文 | 35710篇 |
免费 | 527篇 |
国内免费 | 26篇 |
专业分类
教育 | 25238篇 |
科学研究 | 3469篇 |
各国文化 | 372篇 |
体育 | 3044篇 |
综合类 | 24篇 |
文化理论 | 370篇 |
信息传播 | 3746篇 |
出版年
2021年 | 355篇 |
2020年 | 551篇 |
2019年 | 793篇 |
2018年 | 1101篇 |
2017年 | 1054篇 |
2016年 | 1023篇 |
2015年 | 637篇 |
2014年 | 861篇 |
2013年 | 6315篇 |
2012年 | 785篇 |
2011年 | 827篇 |
2010年 | 676篇 |
2009年 | 681篇 |
2008年 | 749篇 |
2007年 | 709篇 |
2006年 | 673篇 |
2005年 | 567篇 |
2004年 | 636篇 |
2003年 | 517篇 |
2002年 | 546篇 |
2001年 | 718篇 |
2000年 | 778篇 |
1999年 | 639篇 |
1998年 | 385篇 |
1997年 | 423篇 |
1996年 | 473篇 |
1995年 | 368篇 |
1994年 | 383篇 |
1993年 | 329篇 |
1992年 | 522篇 |
1991年 | 526篇 |
1990年 | 528篇 |
1989年 | 529篇 |
1988年 | 478篇 |
1987年 | 478篇 |
1986年 | 465篇 |
1985年 | 541篇 |
1984年 | 424篇 |
1983年 | 426篇 |
1982年 | 356篇 |
1981年 | 347篇 |
1980年 | 358篇 |
1979年 | 487篇 |
1978年 | 373篇 |
1977年 | 337篇 |
1976年 | 282篇 |
1975年 | 264篇 |
1974年 | 264篇 |
1973年 | 256篇 |
1971年 | 251篇 |
排序方式: 共有10000条查询结果,搜索用时 109 毫秒
971.
T.S. Kaeding M.A. 《Sportwissenschaft》2009,39(1):45-51
The consequences of falls can be considerable for elderly people. They often lead to fractures or other injuries, immobility, curtailed independence, need for long-term care, and even death. They decrease the quality of life and can exert a negative influence on self-esteem, activity level, and the number of social contacts. The annual rate of falls in people over 65 is approximately 30%. This number increases to about 50% up to the age of 80 years and almost half of those who fall do so more than once during the course of a year. More than 90% of all falls occur in everyday situations, mostly resulting from movement errors. All studies demonstrated a significant correlation between muscle weakness and the incidence of falls, thus representing a major risk factor for a fall. Gait disorders, hip fractures, and the loss of functional autonomy are closely related to falls and associated with age to a similar extent. Almost 90% of hip fractures in Germany are the result of a fall. From the individual and economic points of view, a fracture near the hip has serious consequences in old age. Based on research findings to date, vibration training could constitute an interesting alternative to classic methods of strength training in fall prevention programs. The aim of this contribution is to provide fundamental facts regarding epidemiology and prevention and to present a potential approach to implementing vibration training in multimodal programs designed to prevent falls. 相似文献
972.
Soccer in Australia underwent a series of changes following a Federal Government inquiry into its future. A report into the Structure, Governance and Management of Soccer in Australia (2003) recommended a process of structural change, aimed at repositioning and re-branding soccer as association football. The restructure yielded the replacement of the National Soccer League with the A-League, five new Australian teams and a concerted attempt to separate soccer from its ethnic ties in the antipodes. This paper examines member identification in relation to a specific A-League club’s members. Using the Sports Spectator Identity Scale (Wann & Branscombe, 1993) to measure sport fan identity in a new team context, a survey of club members of Sydney FC (n = 510), was undertaken. Survey findings indicated that members of Sydney FC reported relatively strong team identification in the first year of the new competition, with some nuanced differences based on age and income. The SSIS demonstrated a good level of fit in relation to a new sports team, although it is evident that rivalries and identification with a new team need time to develop fully. 相似文献
973.
Understanding the role of shaft stiffness in the golf swing 总被引:3,自引:3,他引:0
Theoretically, shaft stiffness can alter shot distance by increasing clubhead speed or altering clubhead orientation at impact.
A 3D forward dynamics model of a golfer and flexible club simulated the downswing. A genetic algorithm optimized the coordination
of the model’s muscles (four torque generators) to maximize clubhead speed. The maximum torque output and maximum rate of
torque development from the torque generators were varied to simulate the swing of golfers that generate different clubhead
speeds. Four shafts of varying stiffness (flexible, regular, stiff, and completely rigid) were entered into these simulations
to examine the role that shaft flexibility had on clubhead speed and orientation at impact. Shaft stiffness was found to have
a meaningful effect only on clubhead orientation (dynamic loft and dynamic close) at impact. There was no evidence to support
the premise that matching the stiffness properties of the shaft with the golfer would improve clubhead speed. 相似文献
974.
Understanding Leadership in Major Sporting Events: The Case of the 2005 World Aquatics Championships
The purpose of this paper was to begin understanding leadership within a major sporting event. A case study of the 2005 Fédération Internationale de Natation (FINA) World Aquatics Championships was built by means of interviews and archival material, using a multi-stakeholder perspective. Findings highlighted that core elements of upper-management level leadership in events were best described by the multiple-linkage leadership theory, which includes task commitment, ability and role clarity, work organization, cooperation and mutual trust, resources and support, and external coordination as the six intervening variables. While charismatic and transformational leadership styles surfaced as contributing to the overall success of an event, the multiple-linkage leadership theory offered a more comprehensive understanding of leadership in major sporting events from a multi-stakeholder perspective. 相似文献
975.
976.
Tyler J. Stidwill Rene Albert Turcotte Phil Dixon David J. Pearsall 《Sports Engineering》2009,12(2):63-68
The purpose of this study was to develop a portable force measurement system for ice hockey skating. The system consisted
of three strain gauge pairs affixed to an ice hockey skate’s blade holder with wire leads connected to a microprocessor controlled
data acquisition device carried in a backpack worn by the skater. The configuration of the strain gauges simultaneously determined
the vertical and medial–lateral force components experienced by the blade holder with a resolution accuracy of 1.9 N and a
coefficient of variation of 9.2%. On-ice testing of this system with subjects performing forward start, acceleration, and
constant velocity skating permitted unencumbered, natural movement and demonstrated clear, unambiguous signal responses, high
trial-to-trial repeatability, and easy data retrieval. The practicality and accuracy of this testing approach have many applications,
such as a quantitative tool for skating force assessment to aid athletes and coaches, as well as providing the means to examine
other skill-specific dynamics. 相似文献
977.
Previous literature has documented the impact of critics on audience choices of movies. We investigate three issues regarding professional critics in the motion picture industry. First we document whether and to what extent critics and their recommendations exhibit a statistical bias toward specific studios. We show that reviews by a number of critics are significantly affected by the film distributor’s identity. A second question is whether audiences are able to distinguish between biased and unbiased critics. We cannot support the view that audiences put less weight on the views of biased critics; in fact, they may listen to them more. Third, we try to characterize critics who are more prone to bias. Surprisingly, but in accord with reputation models, we find that more reputable critics may be more biased; in particular, critics based in L.A. tend to significantly prefer specific studios.
相似文献
Suman BasuroyEmail: |
978.
Accurate measurement of physical activity is fundamentally important in epidemiological research of physical activity behavior A widely used telephone-based physical activity questionnaire was compared with other methods of administration and objective measures (pedometers and accelerometers) among 80 adults (43 women). The telephone questionnaire was comparable to both the self-administered form and international telephone-administered equivalent. Although moderate correlation coefficients with objective measures supported the use of the questionnaire, wide prediction intervals generated using Bland Altman methods highlighted large discrepancies between the measures, particularly in the moderate intensity category. These findings illustrate the limitations of correlation coefficients in validation studies and the inaccuracy of self-report questionnaires in measuring physical activity. 相似文献
979.
Although the importance of high motivation to engage in deliberate practice has been acknowledged, no research has directly tested this hypothesis. Therefore, the present study examined this relation in adolescent elite chess players by means of a questionnaire. In addition, to provide an explanation for dropout among promising chess players, differences in motivation between persistent and dropout chess players were analyzed. Competitiveness and the will to excel proved to be predictors of investments in deliberate practice. Moreover, achievement motivation and chess-specific motivation differed to a certain extent between persisters and dropouts. Our results suggest that motivation to engage in deliberate practice not only contains elements of the will to improve performance, but also of the will to attain exceptional levels of performance. 相似文献
980.
Comparison of two Actigraph models for assessing free-living physical activity in Indian adolescents
Corder K Brage S Ramachandran A Snehalatha C Wareham N Ekelund U 《Journal of sports sciences》2007,25(14):1607-1611
This aim of this study was to compare the new Actigraph (GT1M) with the widely used Model 7164. Seven days of free-living physical activity were measured simultaneously using both the Model 7164 and GT1M in 30 Indian adolescents (mean age 15.8 years, s = 0.6). The GT1M was on average 9% lower per epoch than model 7164, thus a correction factor of 0.91 is suggested for comparison between the two monitors. The differences between monitors increased in magnitude with intensity of activity (P < 0.001) but remained randomly distributed (r = 0.01, P = 0.96). No significant difference was observed between monitors for time spent in moderate (P = 0.31) and vigorous (P = 0.34) physical activity when using the same epoch length. The Model 7164 classified less time as sedentary (P < 0.001) and more time as light-intensity activity (P < 0.001) than the GT1M. In conclusion, data from the GT1M can be compared with historical data using average counts per minute with a correction factor, and the two models might be comparable for assessing time spent in moderate to vigorous physical activity in children when using the same epoch length. 相似文献