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   23320篇
  免费   406篇
  国内免费   31篇
教育   16820篇
科学研究   2022篇
各国文化   220篇
体育   1804篇
综合类   35篇
文化理论   204篇
信息传播   2652篇
  2022年   134篇
  2021年   235篇
  2020年   376篇
  2019年   505篇
  2018年   717篇
  2017年   791篇
  2016年   737篇
  2015年   446篇
  2014年   604篇
  2013年   4458篇
  2012年   584篇
  2011年   652篇
  2010年   500篇
  2009年   473篇
  2008年   535篇
  2007年   524篇
  2006年   459篇
  2005年   409篇
  2004年   381篇
  2003年   349篇
  2002年   396篇
  2001年   430篇
  2000年   414篇
  1999年   406篇
  1998年   219篇
  1997年   238篇
  1996年   263篇
  1995年   224篇
  1994年   220篇
  1993年   212篇
  1992年   313篇
  1991年   321篇
  1990年   340篇
  1989年   323篇
  1988年   303篇
  1987年   255篇
  1986年   267篇
  1985年   330篇
  1984年   268篇
  1983年   262篇
  1982年   205篇
  1981年   213篇
  1980年   184篇
  1979年   251篇
  1978年   221篇
  1977年   197篇
  1976年   168篇
  1975年   131篇
  1974年   124篇
  1973年   154篇
排序方式: 共有10000条查询结果,搜索用时 296 毫秒
961.
962.
Do oarsmen have asymmetries in the strength of their back and leg muscles?   总被引:1,自引:0,他引:1  
The aim of this study was to establish whether asymmetry of the strength of the leg and trunk musculature is more prominent in rowers than in controls. Nineteen oarsmen and 20 male controls matched for age, height and body mass performed a series of isokinetic and isometric strength tests on an isokinetic dynamometer. These strength tests focused on the trunk and leg muscles. Comparisons of strength were made between and within groups for right and left symmetry patterns, hamstring: quadriceps ratios, and trunk flexor and extensor ratios. The results revealed no left and right asymmetries in either the knee extensor or flexor strength parameters (including both isometric and isokinetic measures). Knee extensor strength was significantly greater in the rowing population, but knee flexor strength was similar between the two groups. No difference was seen between the groups for the hamstring: quadriceps strength ratio. In the rowing population, stroke side had no influence on leg strength. No differences were observed in the isometric strength of the trunk flexors and extensors between groups, although EMG activity was significantly higher in the rowing population. Patterns of asymmetry of muscle activity were observed between the left and right erector spinae muscles during extension, which was significantly related to rowing side (P < 0.01). These observations could be related to the high incidence of low back pain in oarsmen.  相似文献   
963.
964.
Three soccer header types (shooting, clearing and passing) and two heading approaches (standing and jumping) were manipulated to quantify impact forces and neck muscle activity in elite female soccer players. The 15 participants were Division I intercollegiate soccer players. Impact forces were measured by a 15-sensor pressure array secured on the forehead. The electromyographic (EMG) activity of the left and right sternocleidomastoid and trapezius muscles was recorded using surface electrodes. Maximum impact forces and impulses as well as the EMG data were analysed with separate repeated-measures analyses of variance. Impact forces and impulses did not differ among the header types or approaches. Higher values were found for jumping versus standing headers in the mean normalized EMG for the right sternocleidomastoid. In addition, the integrated EMG was greater for the right sternocleidomastoid and right and left trapezius (P < 0.05). The sternocleidomastoid became active earlier than the trapezius and showed greater activity before ball contact. The trapezius became active just before ball contact and showed greater activity after ball contact. The increased muscle activity observed in the neck during the jumping approach appears to stabilize the connection between the head and body, thereby increasing the stability of the head-neck complex.  相似文献   
965.
Contemporary aspects of research methods in sport and exercise psychology are discussed in this wide-ranging review. After an introduction centred on trends in sport and exercise psychology methods, the review is organized around the major themes of quantitative and qualitative research. Our aim is to highlight areas that may be problematic or controversial (e.g. stepwise statistical procedures), underused (e.g. discriminant analysis), increasingly used (e.g. meta-analysis, structural equation modelling, qualitative content analysis) and emergent (e.g. realist tales of writing). Perspectives range from the technical and speculative to the controversial and critical. While deliberately not providing a 'cookbook' approach to research methods, we hope to provide enough material to help researchers to appreciate the diversity of potential methods and to adopt a more critical perspective in their own research consumption and production.  相似文献   
966.
Researchers and practitioners require guidelines for using electronic pedometers to objectively quantify physical activity (specifically ambulatory activity) for research and surveillance as well as clinical and program applications. Methodological considerations include choice of metric and length of monitoring frame as well as different data recording and collection procedures. A systematic review of 32 empirical studies suggests we can expect 12,000-16,000 steps/day for 8-10-year-old children (lower for girls than boys); 7,000-13,000 steps/day for relatively healthy, younger adults (lower for women than men); 6,000-8,500 steps/day for healthy older adults; and 3,500-5,500 steps/day for individuals living with disabilities and chronic illnesses. These preliminary recommendations should be modified and refined, as evidence and experience using pedometers accumulates.  相似文献   
967.
968.
This study investigated factors that enhanced and constrained the career development of six teachers, who had graduated from the same university teacher education program, in their induction years (Woods & Earls, 1995) and again later in their career cycles. Three participants were physical education teachers (PETs), and three were former physical education teachers (FPETs). Fessler's (1985) Teacher Career Stage Model provided the theoretical framework. Data sources were: interviews with teachers and their teacher educators and direct observations of lessons. Results indicated that the PETs continued to have skill development as their primary teaching objective. The teachers maintained many of their teaching skills, and shifted between the career cycles of "competency building" and "enthusiastic and growing." All three FPETs left their physical education positions during the career frustration stage and at the time of publication were in the career exit stage.  相似文献   
969.
In any consideration of cultural diffusion, what matters is not only what happens to a cultural form when it arrives, but that it arrives. In the twentieth century, Latin America, like too many other areas of the world, has been a place of diplomatic turmoil, social inequality, political paranoia, capitalist exploitation and class conflict. However, despite all this, and through all this, it may be stated factually and without sentimentality, that it has also been a place where people have survived and thrived, worked, loved and played. Modern sport has brought to their play both unhappy moments of disillusion and disappointment and marvellous opportunities for illusion and pleasure. Modern sport, with its beauty spots and warts, is the reality and while there are things to criticize, there are also many things to applaud. Along with others, the English middle class played a not insignificant part in the arrival of modern sport in Latin America.  相似文献   
970.
Comparison of serial organization of infant babbling and early speech with that of 10 languages reveals four movement-related design features reflecting a deep evolutionary heritage: (1) the cyclical consonant-vowel alternation underlying the syllable, a "Frame" for speech consisting of mandibular oscillation, possibly evolving from ingestive cyclicities (e.g., chewing) via visuofacial communicative cyclicities (e.g., lipsmacks); (2) three intracyclical consonant-vowel co-occurrence preferences reflecting basic biomechanical constraints-coronal consonants-front vowels, dorsal consonants-back vowels, and labial consonants-central vowels; (3) a developmental progression from above-chance to below-chance levels of intercyclical consonant repetition; (4) an ease-related labial consonant-vowel-coronal consonant sequence preference for word initiation. These design features presumably result from self-organizational responses to selection pressures, primarily determined by motor factors. No explanation for these design features is available from Universal Grammar, and, except for feature 3, perceptual-motor learning seems to have only a limited causal role in acquisition of any design feature.  相似文献   
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