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   627篇
  免费   8篇
教育   485篇
科学研究   13篇
各国文化   6篇
体育   81篇
文化理论   2篇
信息传播   48篇
  2023年   11篇
  2021年   10篇
  2020年   15篇
  2019年   28篇
  2018年   35篇
  2017年   41篇
  2016年   38篇
  2015年   26篇
  2014年   18篇
  2013年   151篇
  2012年   16篇
  2011年   17篇
  2010年   23篇
  2009年   13篇
  2008年   14篇
  2007年   14篇
  2006年   17篇
  2005年   8篇
  2004年   8篇
  2003年   14篇
  2002年   16篇
  2001年   3篇
  2000年   8篇
  1999年   6篇
  1998年   5篇
  1997年   7篇
  1996年   10篇
  1995年   5篇
  1994年   4篇
  1992年   2篇
  1991年   3篇
  1989年   4篇
  1988年   2篇
  1987年   2篇
  1986年   2篇
  1984年   2篇
  1983年   6篇
  1982年   3篇
  1980年   3篇
  1979年   4篇
  1978年   2篇
  1977年   2篇
  1975年   2篇
  1974年   2篇
  1972年   1篇
  1971年   2篇
  1968年   1篇
  1967年   1篇
  1963年   1篇
  1925年   1篇
排序方式: 共有635条查询结果,搜索用时 9 毫秒
81.
82.
Abstract

The relationship between junior boys' tennis success, as measured by a top 20 International Tennis Federation's Junior Circuit (ITFJC) ranking, and subsequent ranking accomplishments in professional men's tennis is discussed. The names, countries, and birthdates of all players to achieve a top 20 ITFJC boys' year-end ranking from 1992 to 1998 were recorded. The progress of these players through the professional ranks was then tracked to the end of 2004. Results indicate that 91% of top 20-ranked boys achieved a professional men's ranking, while a stepwise regression analysis revealed junior ranking (JR) to be a predictor of future, professional ranking (β = 0.232, r 2 = 0.054, p < 0.05). A regression equation [predicted professional rank = 78.17 + 6.31?(JR)] accounted for a significant amount of variance in professional ranking. For male players, therefore, the achievement of a top 20 junior ranking appears to be a reasonable yardstick for future, professional success. The type of surface upon which junior players develop their games was also shown to influence professional ranking highs, with play on clay courts or a combination of clay and hard courts helping to produce higher, professionally ranked players than hard court play alone (p≤ 0.01).  相似文献   
83.
ABSTRACT

This study compared five different methods for analyzing accelerometer-measured physical activity (PA) in older adults and assessed the relationship between changes in PA and changes in physical function and depressive symptoms for each method. Older adult females (N = 144, Mage = 83.3 ± 6.4yrs) wore hip accelerometers for six days and completed measures of physical function and depressive symptoms at baseline and six months. Accelerometry data were processed by five methods to estimate PA: 1041 vertical axis cut-point, 15-second vector magnitude (VM) cut-point, 1-second VM algorithm (Activity Index (AI)), machine learned walking algorithm, and individualized cut-point derived from a 400-meter walk. Generalized estimating equations compared PA minutes across methods and showed significant differences between some methods but not others; methods estimated 6-month changes in PA ranging from 4 minutes to over 20 minutes. Linear mixed models for each method tested associations between changes in PA and health. All methods, except the individualized cut-point, had a significant relationship between change in PA and improved physical function and depressive symptoms. This study is among the first to compare accelerometry processing methods and their relationship to health. It is important to recognize the differences in PA estimates and relationship to health outcomes based on data processing method.

Abbreviation: Machine Learning (ML); Short Physical Performance Battery (SPPB); Center of Epidemiologic Studies Depression Scale (CES-D); Physical Activity (PA); Activity Index (AI); Activities of Daily Living (ADL)  相似文献   
84.
Abstract

Success in professional tennis is measured, at least in part, by rankings. However, there is little quantitative evidence to inform stakeholders regarding what represents the typical ranking progress of top-ranked players. The objective of this study was therefore to compare the ranking trajectories of male players whom achieved peak professional rankings in the Top 250, 175, 100, 50, 20 and 10. The 11,396 birthdates and weekly professional rankings of all players between 27 August 1973 and 31 October 2011 were collated. The peak ranks for each athlete according to their both chronological age and number of years on tour were identified and athletes were categorised into one of six career–peak ranking bands. One-way analysis of variance tests confirmed distinctive ranking trajectories, which were most pronounced among Top 10 players. The rankings of these players were statistically distinguishable following players’ second year on tour or by 17 years of age. The ranking signature of all Top 100 players emerged as significantly different to players that failed to enter the Top 100 by their fourth year on the tour. Indeed, the representation of ranking as a function of years on tour should be considered for use by tennis policy-makers in the future.  相似文献   
85.
Tennis     
The study investigated differences in the one‐ (SH) and two‐handed (DH) backhands when hit flat, across‐court (AC) and down‐the‐line (DL), and with heavy topspin DL (TDL). The ability to disguise each of these backhands when hitting the above strokes was also assessed. Eighteen college‐level male tennis players, identified as having a high performance topspin SH (n = 6) or DH (n = 12) backhand drive, participated in the study. Players were required to hit three AC, DL and TDL backhands from the baseline with their preferred technique, while being filmed with two high‐speed video cameras operating at 200 Hz. The highest horizontal velocity backhand for each stroke was analysed. Results indicated that the sequential coordination of five body segments (hips, shoulder, upper arm, forearm, and hand/racquet rotations) was required for the execution of the SH stroke. The same number of segments were generally coordinated in the DH stroke (hips, shoulders, and varying degrees of upper arm and forearm rotations followed by hand/racquet movement). Mature players produced comparable racquet horizontal velocities 0.005 s prior to impact using either the SH or DH backhand technique. The SH backhand was characterised by a more rotated shoulder alignment than the DH stroke (SH: 119.1°; DH: 83.4°) at the completion of the backswing. At impact the ball was impacted further in front (SH: 0.59 m; DH: 0.40 m) and a similar distance to the side of the body (SH: 0.75 m; DH: 0.70 m). Players using the DH backhand technique delayed the horizontal acceleration of the racquet towards the ball (SH: 0.13 s; DH: 0.08 s prior to impact) and thus were capable of displaying a similar hitting motion closer to impact than players with a SH technique.  相似文献   
86.
This paper traces the dramatic proliferation of leadership roles in English primary and secondar schools, due mainly to central government education policy of the past two decades. This has transformed schools from relatively simple to highly complex organizations and has impacted on the working conditions of, and demands on, teachers, together with many aspects of schooling. These changes are illustrated with typical examples of schools' leadership structures and their functioning. Interview data provide teachers' views on, and reactions to, the changes in school leadership. The paper also reviews the ways in which teacher education institutions have responded in terms of providing initial and in‐service education and training to equip the profession for this new and developing challenge. It examines the reception of such programmes by teachers and the reported impact on schools' management and the role of leadership within it.  相似文献   
87.
This paper presents results from an experimental study that examined embedded strategy prompts in digital text and their effects on calibration and metacomprehension accuracies. A sample population of 80 college undergraduates read a digital expository text on the basics of photography. The most robust treatment (mixed) read the text, generated a summary for each page of text, and then was prompted with a metacognitive strategy. The metacognitive treatment received metacognitive strategy prompts only, and the cognitive group implemented the cognitive strategy (summarization) only. A control group read the text with no embedded support. Groups were compared on measures of achievement, attitudes, cognitive load, and metacomprehension and calibration accuracy. Results indicated that a combination of embedded cognitive and metacognitive strategies in digital text improved learner achievement on application-level questions, yielded more accurate predictive calibration, and strengthened the relationship between metacomprehension and performance, all of which are common attributes of an academically successful learner.  相似文献   
88.
This study explores the opportunities and dilemmas that have been encountered by researchers seeking the views of young people with autism. Twelve researchers were interviewed about their experiences in this field. Through exploration of the complex methodological and ethical issues that they encountered, this study aims to better understand how researchers can improve the way they listen to, and engage with, the views of children and young people with autism. This article discusses four themes that emerged from the interviews: power dynamics; building rapport; communication; and meaningful processes and outputs.  相似文献   
89.
OBJECTIVE: This study aimed to establish the views of a group of mental health professionals from various disciplines working in mental health service in a British hospital about the needs of clients who had experienced childhood sexual abuse. METHOD: Staff members were asked to complete an anonymous survey which asked questions relating to knowledge of sexual abuse and its effects, and the needs of clients and staff in working with this client group. A total of 54 people responded to the survey, 42 were female, 11 male. Most (72%) reported having over 10 years experience working in mental health, working in both in-patient and out-patient settings. RESULTS: While respondents were reasonably knowledgeable about childhood sexual abuse, they were not very comfortable, competent or supported in their work with this client group. There were no differences in responses according to the age or gender of respondents, but less experienced staff were more likely to feel supported. Those that had received training and/or supervision felt significantly more capable in working with this client group. CONCLUSIONS: The study offers some support for the development of specialist training, consultancy and supervision programs for mental health staff in the area of child sexual abuse.  相似文献   
90.
Creativity is viewed in different ways in different disciplines: in education it is called ‘innovation’, in business it is ‘entrepreneurship’, in mathematics it is often equated with ‘problem solving’, and in music it is ‘performance’ or ‘composition’. A creative product in different domains is measured against the norms of that domain, with its own rules, approaches and conceptions of creativity.  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