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   2071篇
  免费   20篇
  国内免费   4篇
教育   1513篇
科学研究   195篇
各国文化   21篇
体育   170篇
综合类   12篇
文化理论   40篇
信息传播   144篇
  2023年   5篇
  2022年   29篇
  2021年   47篇
  2020年   54篇
  2019年   96篇
  2018年   121篇
  2017年   121篇
  2016年   87篇
  2015年   64篇
  2014年   75篇
  2013年   326篇
  2012年   71篇
  2011年   60篇
  2010年   69篇
  2009年   45篇
  2008年   50篇
  2007年   49篇
  2006年   43篇
  2005年   73篇
  2004年   74篇
  2003年   96篇
  2002年   72篇
  2001年   66篇
  2000年   37篇
  1999年   22篇
  1998年   9篇
  1997年   6篇
  1996年   9篇
  1995年   16篇
  1994年   10篇
  1993年   6篇
  1992年   6篇
  1991年   12篇
  1990年   7篇
  1989年   13篇
  1986年   5篇
  1985年   7篇
  1984年   4篇
  1983年   4篇
  1982年   8篇
  1981年   6篇
  1980年   7篇
  1978年   6篇
  1977年   7篇
  1975年   4篇
  1974年   8篇
  1973年   6篇
  1967年   4篇
  1966年   6篇
  1963年   6篇
排序方式: 共有2095条查询结果,搜索用时 0 毫秒
71.
Aim was to identify critical load (CL) in young and elderly apparently healthy male cohorts. To contrast the metabolic, cardiovascular and perceptual responses on CL according to age. We evaluated 12 young (23 ± 3 years) and 10 elderly (70 ± 2 years) apparently healthy active males, who underwent: (1) 1 repetition maximum (1RM) test on a 45° Leg Press; (2) on different days, three high-intensity resistance exercise constant load tests (60%, 75% and 90% 1RM) until fatigue (Tlim). Absolute values of both the CL asymptote and curvature constant (kg) were significantly lower in elderly subjects (P < 0.05). In contrast, elderly subjects demonstrated a significantly higher number of repetitions at CL when compared with young subjects (P < 0.05). As expected, oxygen uptake (VO2) and heart rate (HR) during maximal aerobic exercise testing were significantly reduced in older subjects. However, percent-predicted aerobic capacity were higher in older subjects (P < 0.05). In addition, blood lactate ([La?]) corrected to Tlim and rating of perceived exertion values were greater in younger subjects at all intensities (P < 0.05). These findings, despite reduced force production in older subjects, endurance-related parameters are well preserved according to age-adjusted percent-predicted values in apparently healthy males.  相似文献   
72.
ABSTRACT

Videogames often confront players with frustratingly difficult challenges, fearsome enemies, and tragic stories. As such, they can evoke feelings of failure, sadness, anger, and fear. Although these feelings are usually regarded as undesirable, many players seem to enjoy videogames which cause them. In this paper, I argue that player misery often originates from a fictional or lusory attitude which brackets game events from real-life, making the player’s emotions solely relevant within the game context. As they are part of the game themselves, these negative emotions can be enjoyed and easily relativized, since players can acknowledge that their cause is ‘only a game’. However, there are feelings of misery associated with the playing of videogames which are not caused by either the game’s fiction or challenge. In the last part of this paper, I describe a qualitatively different kind of player misery: one that is caused by elements that are not perceived as part of the game by the player, and is not bracketed from real life by a lusory or fictional attitude.  相似文献   
73.
青年女子排球运动员弹跳力模型的研制   总被引:2,自引:0,他引:2  
为了探索发展青年女子排球运动员弹跳力的有效途径 ,以四川青年女子排球队 9名运动员和重庆女子排球队 13名运动员为研究对象 ,对有关弹跳力的多种因素进行了相关、多元回归分析 ,进而制定出发展弹跳力的回归模型 ,为青年女子排球运动员弹跳力训练提供参考  相似文献   
74.
ABSTRACT

The preservation of artefacts in museum collections is profoundly affected by fluctuations in temperature and, especially, relative humidity (RH). Since the late nineteenth century, many studies have been carried out on the best way to control hygrothermal conditions. In old buildings located in maritime temperate climate zones (such as Portugal) with strong thermal inertia, and which have low ventilation rate (relative to the volume and number of visitors), daily and seasonal hygroscopic inertia may help to assure the maintenance of RH stabilization conditions. The use of expensive active systems may be minimized through the passive behaviour of internal finishing building materials. This work presents the results of an experimental laboratory study conducted in a flow chamber to demonstrate the enormous potential of hygroscopic materials in stabilizing interior relative humidity. Based in these results and in-situ monitoring in a museum housed in a building, located in Porto, with a typical construction of the 1950s (granite masonry and reinforced concrete slabs), a numerical analysis was done to quantify the influence of hygroscopic materials in stabilizing the interior relative humidity.  相似文献   
75.
Health sciences librarians are being called upon to be more proactive in their institutions' continuing education efforts. In an effort to identify whether search requests indicated CE needs, a study was conducted by a group of members of GaIN (Georgia Interactive Network for Medical Information). MEDLINE requests from health care professionals for subject specific clinical topics were collected during a six-month period via a standard search request form created for the study. Copies of all completed requests were collected and broad ICD-9 codes assigned to the search topics. Institutional reports were generated for each participating library to share with hospital CE coordinators. They were also compiled for the group as a whole, and reflected the "hottest" topics requested during the study period for physicians and for non-physicians (nurses, allied health, administrators). A survey to hospital librarians and CE educators showed some value in the reports, but greater potential for further collaboration between librarians and CE coordinators.  相似文献   
76.
77.
78.
Based on a discussion about appraisal which has been going on for over a 100 years, the so-called vertical and horizontal appraisal have been developed and tested since the middle of the 1990s. During this process the tasks, functions and competences of the agencies, which are to be appraised were analysed. The appraisal of the content itself is undertaken only when multiple archival processing has been eliminated by this method and the most significant records identified. Actual tasks and functions of single administrative branches of different institutions (federal government, states, counties, and municipalities) are appraised, apart from already closed records. In this way, agencies creating archives and records today receive written decisions on the appraisal of records, which will be offered to the archives in future. Archivists of different institutions are involved in this appraisal procedure. The experience gained here has continually developed the techniques of vertical and horizontal appraisal. This appraisal procedure is being further developed in a constant balance between theory and practice.  相似文献   
79.
While archivists in western and eastern Germany may have different traditions, they face the same challenges presented by the use of information technology in government offices in recent years. Documentation strategies and goals in advising agencies must be developed in consideration of current professional debate and limited resources. The following article presents tendencies in governmental records management, advising strategies of archives, and schemes for broad-scale appraisal based on observations at the level of the governments of the German Länder and includes case studies from Saxony.  相似文献   
80.
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