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   1218篇
  免费   46篇
  国内免费   60篇
教育   630篇
科学研究   294篇
体育   192篇
综合类   151篇
信息传播   57篇
  2023年   19篇
  2022年   37篇
  2021年   47篇
  2020年   58篇
  2019年   43篇
  2018年   37篇
  2017年   26篇
  2016年   39篇
  2015年   52篇
  2014年   92篇
  2013年   121篇
  2012年   82篇
  2011年   84篇
  2010年   64篇
  2009年   51篇
  2008年   66篇
  2007年   66篇
  2006年   65篇
  2005年   38篇
  2004年   42篇
  2003年   37篇
  2002年   31篇
  2001年   30篇
  2000年   34篇
  1999年   9篇
  1998年   6篇
  1997年   6篇
  1996年   6篇
  1995年   7篇
  1994年   5篇
  1993年   7篇
  1992年   2篇
  1991年   3篇
  1990年   2篇
  1989年   4篇
  1985年   1篇
  1976年   2篇
  1957年   3篇
排序方式: 共有1324条查询结果,搜索用时 15 毫秒
51.
王夫之一生与南岳有着不解之缘。《莲峰志》是王夫之为南岳所写的山志,共五卷十二篇,二万二千七百六十多字。它是王夫之创作的唯一的一部山志,也是南岳七十二峰唯一的一部名峰专志,开南岳方志佳作之先河。此书对于南岳历史文化的价值,对王夫之研究的价值,都有着重要的意义。  相似文献   
52.
Knee flexor and extensor muscular assessment via isokinetic dynamometry is common practice and established in the research literature. However, reporting assessment methodology regarding reciprocal and nonreciprocal movements is often vague or absent. Such methodological issues are crucial for accurate assessments. Therefore, knee extensor and flexor peak moment using either reciprocal movement or nonreciprocal modalities was assessed. Fifteen participants performed three blocks of five concentric muscle actions at three angular velocities [1: nonreciprocal (maximal active flexion followed by passive extension); B2: reciprocal (maximal active extension followed by maximal active flexion); B3 nonreciprocal (maximal active extension followed by passive flexion)]. ANOVA revealed statistically significant within-subject modality effects for peak knee extensor moment and flexor velocity and modality differences (p < .05). Reciprocal and nonreciprocal assessments give significantly different results, with nonreciprocal giving higher peak moments. Reporting which modality is used is crucial to allow for greater clarity for the reader and practitioner.  相似文献   
53.
The aim of this study was to ascertain if gear ratio selection would have an effect on peak power and time to peak power production in elite Bicycle Motocross (BMX) cyclists. Eight male elite BMX riders volunteered for the study. Each rider performed three, 10-s maximal sprints on an Olympic standard indoor BMX track. The riders’ bicycles were fitted with a portable SRM power meter. Each rider performed the three sprints using gear ratios of 41/16, 43/16 and 45/16 tooth. The results from the 41/16 and 45/16 gear ratios were compared to the current standard 43/16 gear ratio. Statistically, significant differences were found between the gear ratios for peak power (F(2,14)?=?6.448; p?=?.010) and peak torque (F(2,14)?=?4.777; p?=?.026), but no significant difference was found for time to peak power (F(2,14)?=?0.200; p?=?.821). When comparing gear ratios, the results showed a 45/16 gear ratio elicited the highest peak power,1658?±?221?W, compared to 1436?±?129?W and 1380?±?56?W, for the 43/16 and 41/16 ratios, respectively. The time to peak power showed a 41/16 tooth gear ratio attained peak power in ?0.01?s and a 45/16 in 0.22?s compared to the 43/16. The findings of this study suggest that gear ratio choice has a significant effect on peak power production, though time to peak power output is not significantly affected. Therefore, selecting a higher gear ratio results in riders attaining higher power outputs without reducing their start time.  相似文献   
54.
Abstract

Quiet eye training (QET) may be a more effective method for teaching children to catch than traditional training (TT) methods, but it is unclear if the benefits accrued persist in the long term. Thirty children were randomly allocated into a QET or TT group and, while wearing a mobile eye tracker, underwent baseline testing, training and two retention tests over a period of eight weeks, using a validated throw and catch task. During training, movement-related information was provided to both groups, while the QET group received additional instruction to increase the duration of their targeting fixation (QE1) on the wall prior to the throw, and pursuit tracking (QE2) period on the ball prior to catching. In both immediate (R1) and delayed (R2, six weeks later) retention tests, the QET group had a significantly longer QE1 duration and an earlier and longer QE2 duration, compared to the TT group, who revealed no improvements. A performance advantage was also found for the QET compared to the TT group at both R1 and R2, revealing the relatively robust nature of the visuomotor alterations. Regression analyses suggested that only the duration of QE1 predicted variance in catch success post-training, pointing to the importance of a pre-programming visuomotor strategy for successful throw and catch performance.  相似文献   
55.
Clutch performance is improved performance under pressure. However, little research has examined the psychological state experienced by athletes in these situations. Therefore, this study qualitatively examined the subjective experience underlying clutch performance across a range of sports (e.g., team, individual) and standards (Olympic to recreational athletes). Sixteen athletes (Mage = 27.08 years; SD = 6.48) took part in in-depth, semi-structured interviews primarily after an exceptional performance (M = 4.38 days later; SD = 3.14). Data were analysed inductively and thematically. Clutch states involved 12 characteristics, including heightened and deliberate concentration, intense effort, and heightened awareness, which distinguished the experience of clutch from other optimal psychological states such as flow. Other characteristics, such as perceptions of control, were also reported and supported previous experimental research on clutch. These findings present in-depth qualitative insights into the psychological state underlying clutch performance, and are discussed in relation to the existing literature on optimal psychological states in sport.  相似文献   
56.
在第10届全运会信息服务研究的基础土,总结经验,对全运会信息服务从组织管理、服务方式、内容、重点及保障等方面进行论述,提出以信息提供、专题研究为主要手段,重点项目、主要对手为主要研究内容,以远期、近期、赛前为时间尺度的三个阶段的团体名次预测等进行信息研究。  相似文献   
57.
采用德国Isomed2000等速肌力测试系统,通过对优秀攀岩运动员左右肘关节正反两握法下的等速向心肌力及峰力矩角度的测试与分析,探讨肘关节屈伸肌群在攀岩竞技能力发展中的作用,为科学安排专项训练及预防运动损伤提供一定的理论依据。其测试结果表明:优秀攀岩运动员肘关节屈伸峰力矩(PT)随测试速度的增大而减小,峰力矩屈伸比值随...  相似文献   
58.
人体生长发育过程中,具有非等比性和向心律的特点,在生长发育结束以前测评出的形态比例关系,不能直接说明成熟后的情况。通过对7~18岁儿童少年发育状况的调研,提出了人体上下肢长与身高比例关系的预测方法。  相似文献   
59.
脑力、体力劳动者足底压力参数分布特征及评定   总被引:3,自引:0,他引:3  
通过分析脑力、体力劳动者自然行走过程中峰力值(maxforce,MF)、达峰力值时间(time to max force)、冲量(impulse)等参数特征,探讨职业对足底压力分布的影响。采用比利时Footscan USB2平板式足底压测试系统对50名普通健康脑力劳动者和63名普通健康体力劳动者进行自然行走过程中动态足底压力测试。结果显示:脑力、体力劳动者左脚Toel、Toe2-5、Heel Lateral区域平均峰值(MF)存在显著性差异,右脚Mid foot、Meta5区域MF差异存在非常显著性(P〈0.01),左、右双足平均峰力值(MF)最大值均出现在足跟内侧(Heel Medial)。脑力、体力劳动者足底各区域达峰力值的时间(TMF),左右双足差异均存在非常显著性(P〈0.01)。脑力劳动者与体力劳动者行走过程中左足在Toel、Toe2-5、Meta1、Heel Medial、Heel Lateral区域的冲量(Impulse,IP),体力劳动者明显大于脑力劳动者且具有显著性差异〈0.01),体力劳动者与脑力劳动者的足底MF与足弓接触面积及足角度存在不同程度的相关。结果说明:脑力劳动者与体力劳动者行走过程中左右双足的平均峰力值、接触面积、冲量等参数都存在不同程度的差异,可能与长期从事的职业不同有关,建议经常进行体育锻炼或定制矫形鞋垫,可以缓解足底压力高压区的过度集中,不断维护足健康水平。  相似文献   
60.
主要运用文献资料法、数理统计法对我国女子七项全能运动员的成绩进行了数据统计及关联度分析。结果表明:女子七项全能总成绩中影响最大的单项成绩是100m栏,其次是铅球和跳远,然后是200m,相对影响较小的是800m和跳高,而总分与各类项目的关联中,速度类项目与总分的关联度最高,其次是投掷类项目而对于耐力类和跳跃类项目尤其是跳跃类项目相比较而言关联度最低。基于灰色建模理论的灰色预测法,建立我国女子七项全能的灰色GM(1,1)预测模型,为我国女子七项全能运动的发展趋势进行预测提供理论性依据。  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