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171.
The aim of this study was to determine how shaft length affects golf driving performance. A range of drivers with lengths between 1.168 m and 1.270 m, representing lengths close to the 1.219 m limit imposed by R&A Rules Limited (2008), were assembled and evaluated. Clubhead and ball launch conditions and drive distance and accuracy were determined for seven category 1 golfers (handicaps 0.21 +/- 2.41) who performed shots on a purpose-built practice hole. As shaft length increased from 1.168 m to 1.270 m, initial ball velocity increased (+ 1.8 m/s, P < 0.01). Ball carry (+ 4.3 m, P = 0.152) also increased, although not significantly so. Furthermore, as shaft length increased, for all club comparisons there was no decrease in accuracy. Ball launch conditions of spin components and launch angle remained unaffected by shaft length. Launch angle increased (0.8 degree, F = 1.074, P = 0.362) as driver shaft length increased. Our results show that clubhead and ball velocity together with ball carry tended to increase with no loss of accuracy.  相似文献   
172.
In this study, we assessed the performance of trained senior (n = 6) and veteran (n = 6) cyclists (mean age 28 years, s = 3 and 57 years, s = 4 respectively). Each competitor completed two cycling tests, a ramped peak aerobic test and an indoor 16.1-km time-trial. The tests were performed using a Kingcycle ergometer with the cyclists riding their own bicycle fitted with an SRM powermeter. Power output, heart rate, and gas exchange variables were recorded continuously and blood lactate concentration [HLa] was assessed 3 min after the peak ramped test and at 2.5-min intervals during the time-trial. Peak values for power output (RMP(max)), heart rate (HR(peak)), oxygen uptake (VO2(peak)), and ventilation (V(Epeak)) attained during the ramped test were higher in the senior group (P < 0.05), whereas [HLa](peak), RER(peak), V(E): VO2(peak), and economy(peak) were similar between groups (P > 0.05). Time-trial values (mean for duration of race) for power output (W(TT)), heart rate (HR(TT)), VO2 (VO(2TT)), and V(E) (V(ETT)) were higher in the seniors (P < 0.05), but [HLa](TT), RER(TT), V(ETT): VO2(TT), and economy(TT) were similar between the groups (P > 0.05). Time-trial exercise intensity, expressed as %RMP(max), %HR(peak), % VO2(peak), and % V(Epeak), was similar (P > 0.05) for seniors and veterans (W(TT): 81%, s = 2 vs. 78%, s = 8; HR(TT): 96%, s = 4 vs. 94%, s = 4; VO2(TT): 92%, s = 4 vs. 95%, s = 10; V(ETT): 89%, s = 8 vs. 85%, s = 8, respectively). Overall, seniors attained higher absolute values for power output, heart rate, VO2, and V(E) but not blood lactate concentration, respiratory exchange ratio (RER), V(E): VO2, and economy. Veterans did not accommodate age-related declines in time trial performance by maintaining higher relative exercise intensity.  相似文献   
173.
A dynamic model of the breast during exercise   总被引:1,自引:1,他引:0  
The aim of this paper is to develop a method to determine the material characteristics of bras that could limit breast motion during exercise. A single participant ran on a treadmill at 10 km h−1 wearing either a sports bra, an everyday bra or no bra. The relative motion between the suprasternal notch and the breast was recorded using a passive marker system at 200 Hz and was modelled as forced damped-harmonic motion with a linear spring and damper, with the driving force provided by the suprasternal notch. The spring and damper values were found by matching the model to the experimental data. It was found that both the damping and stiffness values increased with the use of an everyday bra, and increased further still with the use of a sports bra. The stiffness parameter, however, was shown to be the most important criterion for minimisation of the breast motion. The model predicted that an increase in breast mass from 100 to 700 g (a 32A-cup to a 32F-cup) increased the vertical motion of the unsupported breast by around 70% when running and 30% when walking. This was reduced with an everyday bra and further reduced with the high stiffness sports bra. Although predictions were sensible, the model requires further verification with a cohort of participants.  相似文献   
174.
Children with autistic spectrum disorders (ASD) characteristically display a lack of shared attention behaviours and the lack of these behaviours impacts on their ability to develop social interactions and relationships with others. Steve Solomons, assistant headteacher at Rectory Paddock School and Research Unit in the London Borough of Bromley, set out to explore these issues as an aspect of practice when he was working at St. Ann's School in the London Borough of Merton. He carried out this research as part of his MEd in special education at the University of Birmingham, for which he received the prestigious Annie Deakins prize in 2003. The aim of his study was to investigate whether aromatherapy massage could increase shared attention behaviours in a sample of four children with autistic spectrum disorders and severe learning difficulties (SLD). Aromatherapy massage was introduced into the daily timetable and children's responses were observed. The results indicate that children's shared attention behaviours increased during aromatherapy massage and that other aspects of their behaviour also changed over the course of the research. Family involvement in the study enabled these changes to be transferred from school to home. In this article, Steve Solomons explores the implications of his research for new teaching and learning opportunities for children with autistic spectrum disorders and severe learning difficulties.  相似文献   
175.
176.
This article provides a brief history of the development of the MEDLINE database and its huge impact within the UK, from its inception to the present time. The origins of MEDLINE can be traced back to a collection of books in the US Surgeon General's Office during the American Civil War and John Shaw Billings' decision, during 1867, to make this Library as complete as possible. From these beginnings, Index Medicus was developed in the early years of the 20th century, and electronic versions of the database began with the computerized on-demand search service MEDLARS in 1964 and then via CD-ROM and Internet Grateful Med to the web-based and free-to-all service, PubMed, in 1997. The response to PubMed was immediate and startling with usage increasing from 7 million searches per annum in 1996 to 400 million searches per annum in 2001 and the service continues to improve. MEDLINE providers are now offering mapping of natural language queries to the sophisticated indexing vocabulary (Medical Subject Headings, MeSH) and the provision of specific filters for different types of publication to improve searching efficiency, as well as links to full-text versions of the papers where available. The next steps are likely to involve an increased blurring of database and full-text boundaries, incorporating seamless access to the best available evidence within MEDLINE and a wide range of other information resources within a single search and to an increasing amount of full-text via various open-archive initiatives. As ever, the US National Library of Medicine is in the vanguard of research and further applications of its MEDLINE database for users within the UK will be awaited with great interest.  相似文献   
177.
The documentation of seven academic institutional repositories (IRs) was compared and contrasted. This was followed by semi‐structured interviews with six practitioners experienced in the set‐up, management and maintenance of IRs, including representatives of three JISC FAIR projects. The aim was to identify the requirements of policy documentation provided by IRs. Although many issues were found to be handled differently, several common factors emerged. These included the importance of developing documentation in collaboration with academics, departments and senior management. Policies should be formulated only when the aims of the IR have been clearly defined and the documentation itself should be concise and understandable, with the rights and responsibilities of stakeholders clearly presented.  相似文献   
178.
The CLAT provided considerable information about children’s attitudes and knowledge well beyond computer literacy. It revealed improvements in the use of language, as well as in spelling and penmanship. I understand very well that evaluation engineers would prefer to “partner with teachers” to ensure more thorough grant-funded documentation of the many and diverse process and product outcomes of computer technology expenditures (Baker, 1999). However, a simple count of computer-related terms listed by students appeared, for my limited purposes, to be both a valid and reliable indicator of at least one small aspect of computer literacy  相似文献   
179.
Unreal Friends     
It has become quite common for people to develop `personal' relationships nowadays, exclusively via extensive correspondence across the Net. Friendships, even romantic love relationships, are apparently, flourishing. But what kind of relations really are possible in this way? In this paper, we focus on the case of close friendship. There are various important markers that identify a relationship as one of close friendship. One will have, for instance, strong affection for the other, a disposition to act for their well-being and a desire for shared experiences. Now obviously, while all these features of friendship can gain some expression through extensive correspondence on the Net, such expression is necessarily limited –you cannot, e.g., physically embrace the other, or go on a picnic together. The issue we want to address here however, is whether there might be distinctive and important influences on the structure of interaction undertaken on the Net, that affect the kind of identity ``Net-friends'' can develop in relation to one another. In the normal case, one develops a close friendship, and in doing so, one's identity, in part, is shaped by the friendship. To some extent, through extensive shared experience, one comes to see aspects of the world (and of oneself) through the eyes of one's friend and so, in part, one's identity develops in an importantly relational way, i.e., as the product of one's relation with the close friend. In our view, however, on account of the limits of, and/or the kind of, shared contact and experience one can have with another via correspondence on the Net, there are significant structural barriers to developing the sort of relational identity that is a feature of close friendship. In arguing our case here, and by using the case of Net ``friendship'' as our foil, we aim to shed light on the nature and importance of certain sorts of self-expression and relational interaction found in close friendship.  相似文献   
180.
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