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   5726篇
  免费   87篇
  国内免费   21篇
教育   3991篇
科学研究   654篇
各国文化   38篇
体育   420篇
综合类   6篇
文化理论   37篇
信息传播   688篇
  2022年   46篇
  2021年   60篇
  2020年   100篇
  2019年   154篇
  2018年   208篇
  2017年   245篇
  2016年   192篇
  2015年   157篇
  2014年   188篇
  2013年   952篇
  2012年   153篇
  2011年   168篇
  2010年   142篇
  2009年   124篇
  2008年   135篇
  2007年   152篇
  2006年   119篇
  2005年   83篇
  2004年   105篇
  2003年   85篇
  2002年   79篇
  2001年   121篇
  2000年   141篇
  1999年   95篇
  1998年   79篇
  1997年   70篇
  1996年   70篇
  1995年   50篇
  1994年   49篇
  1993年   37篇
  1992年   79篇
  1991年   72篇
  1990年   68篇
  1989年   64篇
  1988年   76篇
  1987年   60篇
  1986年   83篇
  1985年   71篇
  1984年   55篇
  1983年   71篇
  1982年   55篇
  1981年   43篇
  1980年   31篇
  1979年   56篇
  1978年   54篇
  1977年   40篇
  1976年   43篇
  1975年   32篇
  1974年   34篇
  1973年   33篇
排序方式: 共有5834条查询结果,搜索用时 8 毫秒
91.
Form A of the Boehm Test of Basic Concepts (BTBC) was administered to 180 kindergartners—90 boys and 90 girls. Neither their mean scores nor their standard deviations differed significantly, and the distributions of scores for the two groups were virtually identical. Moreover, the application of three internal criteria for bias yielded totally negative results; thus, there was no evidence of either sex differences or sex bias in the data.  相似文献   
92.
Eardrum perforation as evidence of child abuse   总被引:2,自引:0,他引:2  
  相似文献   
93.
Mental health care for foster children in California   总被引:3,自引:0,他引:3  
This paper reports on a study conducted to assess the health care needs of foster children in California. To evaluate foster children's mental health problems and the services provided to meet them, 154 program administrators, social workers, foster parents, and health care providers were interviewed in 14 counties. Foster parents and social workers were interviewed in groups, and foster parents and administrators also completed questionnaires. We found that although all counties care immediately for children who are injured, abused, or ill, only one county performs routine mental health evaluations of all children, and in most counties less than a third of children ever receive such evaluations. Informants identified mental health problems as more severe than medical problems in this population, and they identified four major barriers to access to appropriate therapy. Recommendations are that all children should receive comprehensive mental health evaluations, and procedures for immediate and ongoing care with consistent providers who are sensitive to foster children's needs should be included in case management plans, and covered by improved payment mechanisms. Additionally, communication, coordination and joint planning should be instituted among relevant agencies to address foster children's needs, and increased resources and training should be directed towards social service agencies and foster parents.  相似文献   
94.
95.
96.
Anthropometric dimensions of male powerlifters of varying body mass   总被引:1,自引:1,他引:0  
In this study, we examined the anthropometric dimensions of powerlifters across various body mass (competitive bodyweight) categories. Fifty-four male Oceania competitive powerlifters (9 lightweight, 30 middleweight, and 15 heavyweight) were recruited from one international and two national powerlifting competitions held in New Zealand. Powerlifters were assessed for 37 anthropometric dimensions by ISAK (International Society for the Advancement of Kinanthropometry) level II and III accredited anthropometrists. The powerlifters were highly mesomorphic and had large girths and bony breadths, both in absolute units and when expressed as Z(p)-scores compared through the Phantom (Ross & Wilson, 1974). These anthropometric characteristics were more pronounced in heavyweights, who were significantly heavier, had greater muscle and fat mass, were more endo-mesomorphic, and had larger girths and bony breadths than the lighter lifters. Although middleweight and heavyweight lifters typically had longer segment lengths than the lightweights, all three groups had similar Zp-scores for the segment lengths, indicating similar segment length proportions. While population comparisons would be required to identify any connection between specific anthropometric dimensions that confer a competitive advantage to the expression of maximal strength, anthropometric profiling may prove useful for talent identification and for the assessment of training progression in powerlifting.  相似文献   
97.
98.
99.
The aim of this study was to determine whether gait cycle characteristics are associated with running economy in elite Kenyan runners. Fifteen elite Kenyan male runners completed two constant-speed running sets on a treadmill (12 km ·h?1 and 20 km ·h?1). VO2 and respiratory exchange ratio values were measured to calculate steady-state oxygen and energy cost of running. Gait cycle characteristics and ground contact forces were measured at each speed. Oxygen cost of running at different velocities was 192.2 ± 14.7 ml· kg?1· km?1 at 12 km· h?1 and 184.8 ± 9.9 ml· kg?1· km?1 at 20 km· h?1, which corresponded to a caloric cost of running of 0.94 ± 0.07 kcal ·kg?1·km?1 and 0.93 ± 0.07 kcal· kg?1· km?1. We found no significant correlations between oxygen and energy cost of running and biomechanical variables and ground reaction forces at either 12 or 20 km· h?1. However, ground contact times were ~10.0% shorter (very large effect) than in previously published literature in elite runners at similar speeds, alongside an 8.9% lower oxygen cost (very large effect). These results provide evidence to hypothesise that the short ground contact times may contribute to the exceptional running economy of Kenyan runners.  相似文献   
100.
Abstract

A “look-up line” (LUL) has been proposed for ice hockey, which is an orange 1?m (40′) warning line (WL) painted on the ice at the base of the boards. The LUL purports to provide an early warning to players to keep their head up prior to and as they are being checked. We determined if players looked up more on a rink with the LUL compared to a traditional Control rink. Elite offensive (O) and defensive (D) players competed 1 vs. 1, while wearing an eye tracker that recorded their quiet eye (QE) and fixation and tracking (F-T) and an electrogoniometer that measured head angle. External cameras recorded skate duration during four skate phases: P1 preparation, P2 decision-making, P3 cut to boards, P4 contact. The QE was the final fixation prior to contact between O and D as they skated towards and across the WL during P3 and P4. Skate phase durations (%) did not differ by rink or rink by position. More QE and F-T occurred on the WL on the LUL rink than on the Control. The expected increase in head angle on the LUL rink did not occur during P3 or P4. Post-hoc results also showed O and D skated further from the boards on the LUL rink, suggesting the players preferred to control the puck on white ice, rather than the orange colour of the LUL rink. More research is needed to determine if these results apply to the competitive setting.  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