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   82篇
  免费   2篇
教育   36篇
科学研究   3篇
各国文化   1篇
体育   36篇
文化理论   1篇
信息传播   7篇
  2020年   1篇
  2019年   1篇
  2018年   7篇
  2017年   6篇
  2016年   4篇
  2014年   1篇
  2013年   16篇
  2012年   6篇
  2011年   4篇
  2010年   2篇
  2009年   1篇
  2008年   3篇
  2007年   3篇
  2006年   4篇
  2005年   3篇
  2004年   4篇
  2002年   2篇
  2001年   1篇
  2000年   4篇
  1999年   1篇
  1998年   2篇
  1997年   1篇
  1995年   1篇
  1992年   1篇
  1990年   1篇
  1989年   1篇
  1981年   1篇
  1978年   1篇
  1977年   1篇
排序方式: 共有84条查询结果,搜索用时 15 毫秒
21.
One of the central narratives of the 1908 Olympic Games is the intense Anglo-American acrimony which culminated in the nadir of their sporting relations. One of the major controversies involved the 400 metres final which featured Halswelle, a British athlete, and three Americans – Carpenter, Robbins and Taylor. The final was declared void after Carpenter obstructed Halswelle and was disqualified. In protest the Americans withdrew Robbins and Taylor from the re-run and Halswelle won the gold medal unopposed. This paper explores the 400 metres final from the perspective of the British athlete Wyndham Halswelle utilising his diaries, photo albums, scrapbooks and the papers of his elder brother, Gordon. Serendipitously, the continual digitisation of newspapers also gave further insight into allegations of illegal team tactics by Carpenter and Robbins in the initial race. The article then further exploits these resources to develop a case study of Halswelle as an elite early-twentieth-century British amateur athlete. Differences in ideas of the amateur athlete ideal are often identified as an underpinning cause of international squabbling at the IV Olympiad and may have led to Halswelle’s decision to retire after the games at the age of 26 while still improving his performances.  相似文献   
22.
We present a user-centred, task-oriented, comparative evaluation of two within-document retrieval tools. ProfileSkim computes a relevance profile for a document with respect to a query, and presents the profile as an interactive bar graph. FindSkim provides similar functionality to the web browser “Find” command. A novel simulated work task was devised, where participants are asked to identify (index) relevant pages of an electronic book, given topics from the existing book index. The original book index provides the ground truth, against which the indexing results of the participants can be compared. We confirmed a major hypothesis, namely ProfileSkim proved significantly more efficient than Find-Skim, as measured by time for task. The study indicates that ProfileSkim was as least as effective as FindSkim in identifying relevant pages, as measured by traditional information retrieval measures, and there is some evidence that ProfileSkim is a precision-enhancing tool. Based on qualitative data from questionnaires, we also provide strong evidence to support our conjecture that the participants would be more satisfied when using ProfileSkim than FindSkim. The experimental study confirmed the potential of relevance profiling for improving within-document retrieval. Relevance profiling should prove highly beneficial for users trying to identify relevant information within long documents.  相似文献   
23.
24.
Dynamic behaviour of soils used for natural turf sports surfaces   总被引:1,自引:0,他引:1  
The modulus and damping properties of soils in compression are a function of soil type, water content, stress history and loading rate. To model human–surface interaction with natural turf sports surfaces, stiffness and damping properties must be determined at dynamic loading rates. Two contrasting soil types, a Sand and a Clay Loam, commonly used in sports surfaces were loaded uniaxially to 2 kN at loading rates between 0.6 and 6 kN s−1 in modified dynamic soil testing apparatus. Soils were compacted prior to loading but initial cycles resulted in viscoplastic deformation, with strain accumulation with repeated cycles of loading. Ultimately a resilient, viscoelastic steady-state equilibrium with loading was established. Resilient modulus and damping ratio varied with soil type, water content, stress history and increased significantly with loading rate. The resilient modulus of the Sand soil, typical of modern free-draining sand construction natural turf sports surfaces, was significantly greater than that of a Clay Loam soil more characteristic of traditional natural turf surfaces; reducing water content caused an increase in modulus and a decrease in damping ratio in the Clay Loam soil. Determination of these properties provides initial data for the modelling natural turf surface behaviour in terms of both ball and human interactions, with further research required to determine the effect of both grass roots and leaves on mechanical behaviour.  相似文献   
25.
26.
In the light of predictions of future protein shortages the non-agricultural routes to protein production have become an industrial reality. These routes are based on the continuous fermentation of micro-organisms to produce single cell proteins. Seen as only a long-term possibility a few years ago, many commercial enterprises now have successful SCP production facilities, while research and development in this field continues at a rapid pace.  相似文献   
27.
A case study of a lengthy and potentially disruptive experimental research project is used to examine ways in which the interests of researchers and schools may be reconciled. Attention is drawn particularly to the importance of joint recognition of the legitimacy of both sets of objectives. The pivotal role of a research assistant/teacher in facilitating sensitive and flexible responses to problems confronting both the research project and the school is discussed. Unexpected social benefits to the school arising from our implementation of the research assistant/teacher role are described.  相似文献   
28.
29.
As part of the impetus to increase and widen participation in the UK, and in Scotland in particular, there has been considerable effort put into creating links between Further Education Colleges (FECs) and Higher Education Institutions (HEIs). However, because no unique identifier is used to track students between the two sectors, little is known in quantitative terms of the nature of this progression. In this article using substantial datasets, and an approach known as Probability Matching, we are able to provide novel data on the proportions of Scottish domiciled former FEC students within Scottish HEIs, and are able to compare the characteristics of this subset of all students with the whole cohort within HE in a given year, 1999–2000.  相似文献   
30.

Objective

To investigate the beneficial effect of bicyclol on rat hearts subjected to ischemia-reperfusion (IR) injuries and its possible mechanism.

Methods

Male Sprague-Dawley rats were intragastrically administered with bicyclol (25, 50 or 100 mg/(kg·d)) for 3 d. Myocardial IR was produced by occlusion of the coronary artery for 1 h and reperfusion for 3 h. Left ventricular hemodynamics was continuously monitored. At the end of reperfusion, myocardial infarct was measured by 2,3,5-triphenyltetrazolium chloride (TTC) staining, and serum lactate dehydrogenase (LDH) level and myocardial superoxide dismutase (SOD) activity were determined by spectrophotometry. Isolated ventricular myocytes from adult rats were exposed to 60 min anoxia and 30 min reoxygenation to simulate IR injuries. After reperfusion, cell viability was determined with trypan blue; reactive oxygen species (ROS) and mitochondrial membrane potential of the cardiomyocytes were measured with the fluorescent probe. The mitochondrial permeability transition pore (mPTP) opening induced by Ca2+ (200 μmol/L) was measured with the absorbance at 520 nm in the isolated myocardial mitochondria.

Results

Low dose of bicyclol (25 mg/(kg·d)) had no significant improving effect on all cardiac parameters, whereas pretreatment with high bicyclol markedly reduced the myocardial infarct and improved the left ventricular contractility in the myocardium exposed to IR (P<0.05). Medium dose of bicyclol (50 mg/(kg·d)) markedly improved the myocardial contractility, left ventricular myocyte viability, and SOD activity, as well decreased infarct size, serum LDH level, ROS production, and mitochondrial membrane potential in rat myocardium exposed to IR. The reduction of ventricular myocyte viability in IR group was inhibited by pretreatment with 50 and 100 mg/(kg·d) bicyclol (P<0.05 vs. IR), but not by 25 mg/(kg·d) bicyclol. The opening of mPTP evoked by Ca2+ was significantly inhibited by medium bicyclol.

Conclusions

Bicyclol exerts cardioprotection against IR injury, at least, via reducing oxidative stress and its subsequent mPTP opening.  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