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   21616篇
  免费   186篇
  国内免费   19篇
教育   14380篇
科学研究   3466篇
各国文化   128篇
体育   1379篇
综合类   7篇
文化理论   223篇
信息传播   2238篇
  2021年   182篇
  2020年   260篇
  2019年   375篇
  2018年   1155篇
  2017年   1112篇
  2016年   870篇
  2015年   338篇
  2014年   459篇
  2013年   3253篇
  2012年   474篇
  2011年   701篇
  2010年   609篇
  2009年   469篇
  2008年   551篇
  2007年   610篇
  2006年   299篇
  2005年   361篇
  2004年   412篇
  2003年   316篇
  2002年   272篇
  2001年   341篇
  2000年   363篇
  1999年   317篇
  1998年   171篇
  1997年   220篇
  1996年   211篇
  1995年   146篇
  1994年   186篇
  1993年   146篇
  1992年   252篇
  1991年   234篇
  1990年   230篇
  1989年   278篇
  1988年   221篇
  1987年   187篇
  1986年   244篇
  1985年   235篇
  1984年   194篇
  1983年   198篇
  1982年   154篇
  1981年   139篇
  1980年   135篇
  1979年   212篇
  1978年   152篇
  1977年   148篇
  1976年   135篇
  1975年   112篇
  1974年   141篇
  1973年   123篇
  1971年   125篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Editorial     
B. Sury 《Resonance》2018,23(7):723-725
  相似文献   
3.
4.
5.
The value that willed body donors provide to medical education is priceless. Their precious gift helps to teach anatomy, spatial relationships between morphological structures, anatomical variation, and professionalism to medical students in a way that plastic models, podcasts, and lectures cannot. They are also an important resource for medical research and a wide variety of postgraduate training opportunities. While many body donation programs throughout the world are nonprofit organizations, there are body donation companies in the United States that sell donors for-profit. These “body brokers” have accumulated large profits from this business. It is incongruous that others would profit from such a priceless, freely donated gift. To prevent this incongruity, it is proposed that the international anatomical community develop a normative culture (a bioethos) for body donation programs. This would involve the conscious and systematic development of ethical principles for the day-to-day policies and practices of institutions that collect and use human bodies. With the development of this bioethos, a cultural shift in how donors are treated would occur and, over time, this would become the normal practice. These principles would become fundamental and foundational for the procurement and use of priceless human tissues.  相似文献   
6.
ABSTRACT

This forum brings together food, (in)security, and communication. The authors participating in this forum center communication as both process and tool for understanding, mitigating, and making meaning of food (in)security. The nine authors together discuss the role of communication in food (in)security, the central challenges for scholars and practitioners working on food (in)security, and the creative possibilities and impacts influencing the future of food (in)security. The forum produces a call for applied scholars to re-imagine communication frameworks in order to make meaningful differences in their communities.  相似文献   
7.
8.
9.
10.
We analyse the evolution of the slope (critical speed) and the y-intercept (anaerobic distance capacity) of the linear distance-time relationship over a century of Olympic running performances. The distance-time relationship of each Olympic Games (1920-2004) was plotted using the performances in the 800-, 1500- and 5000-m track events. Values for critical speed and anaerobic distance capacity were determined by linear modelling. Mean performances for the 800, 1500 and 5000 m were 104.9 +/- 1.5 s (1.4%), 217.2 +/- 2.8 s (1.3%) and 808.9 +/- 18.4 s (2.3%), respectively. Critical speed improved during the first three-quarters of the twentieth century to reach a plateau in 1984. This is in accordance with the literature (Peronnet & Thibault, 1989) and suggests that "human aerobic endurance" has improved within the century (+13.4%) and tends to stabilize. Anaerobic distance capacity was highly variable over the century (coefficient of variation = 9.4%) and did not show a linear improvement over the years as has previously been suggested (Peronnet & Thibault, 1989). This could be due to an artefact in the application of the two-parameter model to only three Olympic performances. A limitation to the use of this linear mathematical model to fit physiological data may have been demonstrated.  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