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   14515篇
  免费   173篇
  国内免费   12篇
教育   9851篇
科学研究   1310篇
各国文化   152篇
体育   1506篇
综合类   22篇
文化理论   104篇
信息传播   1755篇
  2021年   109篇
  2020年   209篇
  2019年   299篇
  2018年   342篇
  2017年   414篇
  2016年   364篇
  2015年   238篇
  2014年   319篇
  2013年   2600篇
  2012年   277篇
  2011年   319篇
  2010年   249篇
  2009年   280篇
  2008年   266篇
  2007年   259篇
  2006年   243篇
  2005年   225篇
  2004年   466篇
  2003年   357篇
  2002年   383篇
  2001年   246篇
  2000年   258篇
  1999年   203篇
  1998年   99篇
  1997年   123篇
  1996年   151篇
  1995年   138篇
  1994年   129篇
  1993年   125篇
  1992年   179篇
  1991年   180篇
  1990年   163篇
  1989年   215篇
  1988年   176篇
  1987年   207篇
  1986年   178篇
  1985年   232篇
  1984年   191篇
  1983年   173篇
  1982年   152篇
  1981年   129篇
  1980年   110篇
  1979年   173篇
  1978年   136篇
  1977年   121篇
  1976年   139篇
  1975年   103篇
  1974年   118篇
  1973年   96篇
  1971年   107篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
891.
892.
This is a list of books that should be available in either the hospital emergency room or the medical library. The forty-nine books listed are divided into the following categories: General, Surgery and Trauma, Burns, Cardiology, Dentistry, Disaster Medicine, First Aid, Geriatrics, Obstetrics, Pediatrics, Psychiatry, Toxicology, and Transportation. An asterisk has been placed before twelve books that are particularly recommended for the hospital emergency room as well as the medical library. The latest edition is given for each book, and, unless otherwise noted, each has been annotated by one of the authors.  相似文献   
893.
Since 1962 the members of the loosely organized Detroit Medical Library Group have carried on a slow but steady self-examination program. They found a need to increase resources and developed a periodical exchange, then a need to identify these resources and did so by means of a serials list. More recently, a similar program for texts and monograph resources was begun. Data, more particularly that of the interlibrary loan process, is being gathered to show the flow within the area and the flow from outside to further identify the existing resources. They have made contact with the administrators of the biomedical institutions and gained their backing (a) to further study the makeup of the community and (b) to formulate an administrative structure through which these institutions can act. These activities are evidence of the beginning of a strong medical library network for the Metropolitan Detroit Area.  相似文献   
894.
895.
896.
897.
This investigation was conducted to compare the influence of high and low perceived competence (PC) and various causal dimension orientations on expectations, persistence, and performance while perceiving failure on a motor task. Based on a response to a PC scale, 84 junior high school students were selected to participate in this study. Separately, 42 low and 42 high PC subjects were oriented to perceive their performance on a stabilometer balancing task as due to: (a) internal, controllable, unstable factors (ICU); (b) internal, uncontrollable, stable factors (IUS); or (c) nothing in particular (NDO). Subjects then received fictitious negative feedback over 15 trials. Results revealed that persistence, expectations, and performance dependent measures were significant for PC and Causal Dimension groups. More specifically, the High PC group persisted longer, had higher expectations, and performed significantly better than the Low PC group. Furthermore, the subjects presented ICU orientations persisted for a longer amount of time, revealed higher expectations over trials, and performed significantly better over trials than the subjects in the IUS and NDO groups. These findings suggest that perceived competence and causal dimensional orientations influence children's expectations, persistence, and performance when perceiving failure on a motor task.  相似文献   
898.
In its search for an objective overall diagnostic evaluation, the University of Illinois Library of the Health Sciences' Program Evaluation Committee selected a book availability measure; it is easy to administer and repeat, results are reproducible, and comparable data exist for other academic and health sciences libraries. The study followed the standard methodology in the literature with minor modifications. Patrons searching for particular books were asked to record item(s) needed and the outcome of the search. Library staff members then determined the reasons for failures in obtaining desired items. The results of the study are five performance scores. The first four represent the percentage probability of a library's operating with ideal effectiveness; the last provides an overall performance score. The scores of the Library of the Health Sciences demonstrated no unusual availability problems. The study was easy to implement and provided meaningful, quantitative, and objective data.  相似文献   
899.
Electromyographic analysis of bow string release in highly skilled archers   总被引:3,自引:1,他引:2  
A predominant archery coaching tenet holds that the most effective means of releasing the bow string is by relaxation of the finger flexor muscles without activation of finger extensors. To evaluate the validity of this view, EMG patterns of the flexor digitorum superficialis and extensor digitorum muscles of the draw arm were examined using surface EMG electrodes in 15 highly skilled archers as each performed six shots. Each archer displayed consistent EMG patterns from shot-to-shot and two distinct flexor-extensor patterns were exhibited by the sample. The first, characterized by eight of the archers, supported the relaxation principle. For these archers, both flexor and extensor digitorum activity decreased markedly immediately prior to or at arrow release. The second pattern, characteristic of the remaining seven archers, contradicted the coaching tenet. While the flexor digitorum pattern was essentially the same as that described for the first pattern, the extensor digitorum displayed a marked increase in activity just prior to release, indicating that string release was facilitated by an active extension of the fingers. It was concluded that highly skilled archers do not predominantly reflect a release consistent with the coaching canon and that factors other than the string release mechanism discriminate the performances of skilled archers.  相似文献   
900.
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