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   993篇
  免费   10篇
教育   734篇
科学研究   73篇
各国文化   29篇
体育   77篇
综合类   1篇
文化理论   18篇
信息传播   71篇
  2023年   7篇
  2022年   10篇
  2021年   11篇
  2020年   12篇
  2019年   14篇
  2018年   35篇
  2017年   27篇
  2016年   24篇
  2015年   18篇
  2014年   16篇
  2013年   264篇
  2012年   18篇
  2011年   28篇
  2010年   14篇
  2009年   21篇
  2008年   17篇
  2007年   27篇
  2006年   18篇
  2005年   14篇
  2004年   31篇
  2003年   16篇
  2002年   15篇
  2001年   9篇
  2000年   11篇
  1996年   12篇
  1994年   8篇
  1992年   12篇
  1991年   11篇
  1990年   8篇
  1989年   9篇
  1988年   8篇
  1987年   8篇
  1986年   10篇
  1985年   7篇
  1984年   12篇
  1983年   9篇
  1981年   8篇
  1980年   12篇
  1979年   13篇
  1978年   7篇
  1977年   8篇
  1976年   10篇
  1975年   11篇
  1974年   7篇
  1973年   8篇
  1971年   6篇
  1969年   12篇
  1968年   6篇
  1966年   6篇
  1927年   8篇
排序方式: 共有1003条查询结果,搜索用时 15 毫秒
31.
The power output achieved at peak oxygen consumption (VO2peak) and the time this power can be maintained (i.e., Tmax) have been used in prescribing high-intensity interval training. In this context, the present study examined temporal aspects of the VO2 response to exercise at the cycling power that output well trained cyclists achieve their VO2peak (i.e., Pmax). Following a progressive exercise test to determine VO2peak, 43 well trained male cyclists (M age = 25 years, SD = 6; M mass = 75 kg, SD = 7; M VO2peak = 64.8 ml x kg(-1) x min(-1), SD = 5.2) performed two Tmax tests 1 week apart. Values expressed for each participant are means and standard deviations of these two tests. Participants achieved a mean VO2peak during the Tmax test after 176 s (SD = 40; M = 74% of Tmax, SD = 12) and maintained it for 66 s (SD = 39; M = 26% of Tmax, SD = 12). Additionally, they obtained mean 95% of VO2peak after 147 s (SD = 31; M = 62% of Tmax, SD = 8) and maintained it for 95 s (SD = 38; M = 38% of Tmax, SD = 8). These results suggest that 60-70% of Tmax is an appropriate exercise duration for a population of well trained cyclists to attain VO2peak during exercise at Pmax. However, due to intraparticipant variability in the temporal aspects of the VO2 response to exercise at Pmax, future research is needed to examine whether individual high-intensity interval training programs for well trained endurance athletes might best be prescribed according to an athlete's individual VO2 response to exercise at Pmax.  相似文献   
32.
The aim of this study was to determine the level of awareness of methodological search filters among health and academic librarians in the UK and Ireland, their use of filters and views on the perceived benefits, limitations and ways to increase usage of search filters. A random proportional sample of health and academic librarians were surveyed by telephone and fax. Overall, 88% (196/224) completed the telephone survey to establish awareness and use of filters. Eighty-four per cent (51/61) completed a fax survey focusing in more depth on usability issues surrounding filters. Results indicate a high level of awareness of methodological filters, but low level of usage. Furthermore, a high level of awareness did not necessarily correlate with a high level of knowledge or understanding. Examination of responses revealed limitations and recommendations beyond those reported in the literature and highlights the relationship between understanding and effective use of filters. Improved dissemination and publication of filters is required to better inform librarians on the concept of filters and how to use them effectively.  相似文献   
33.
Thigh muscle volume is a useful determinant of functional fitness. However, anthropometric prediction of muscle content is influenced by the variability of adipose tissue accumulation. The aims of this study were to predict thigh muscle and adipose tissue volumes from anthropometry and to assess the validity of the method by examining the various components of the measurements and the assumptions involved. The 19 participants (9 men, 10 women; age 23-49 years) varied in adiposity. They all underwent magnetic resonance imaging (MRI) of the upper leg and the eight men and two women with the lowest adiposity underwent detailed anthropometry involving girths and skinfolds. Using MRI as the reference method, muscle volume was predictedfrom anthropometry using a circular concentric model, and the assumptions inherent in the method were tested further using the MRI data alone. Muscle volume was best predicted by anthropometry in the 10 leanest participants using a five-slice truncated cone model that overestimated the mean MRI value by 30% (R2 = 0.95; standard error of estimate = 288 cm3; P < 0.001). A single skinfold plus girth measurement at the mid-thigh almost matched its predictive ability, but with an increased bias. Measurements of leg circumference by means of the two techniques agreed well. The assumption of a circular cross-section was valid. In contrast, the agreement between skinfold thickness measured by caliper and superficial adipose tissue thickness by MRI was poor, contributing to the scatter of fat and lean area comparisons. An anterior skinfold thickness measurement underestimated the area of superficial adipose tissue at that level, particularly at the most proximal and distal sites. Although these limitations increase the uncertainties of muscle volume determination by anthropometry, they do not prevent its valid prediction in leaner individuals. The prediction of superficial adipose tissue was poorer.  相似文献   
34.
35.
36.
37.
38.
The purpose of this study was to determine the differences between third and sixth grade female and male students when retelling orally a story read silently. The students' retelling of the story was analyzed by comparing how closely, both structurally and linguistically, they paralleled the T-units or communication units of the author. In general, female students performed significantly differently than did male students. The researchers examine these differences in light of recent research in the area of gender differences.  相似文献   
39.
40.
Educational Studies in Mathematics - The give-n task is widely used in developmental psychology to indicate young children’s knowledge or use of the cardinality principle (CP): the last...  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