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   123501篇
  免费   1850篇
  国内免费   238篇
教育   85949篇
科学研究   13518篇
各国文化   1991篇
体育   9484篇
综合类   177篇
文化理论   1078篇
信息传播   13392篇
  2021年   941篇
  2020年   1660篇
  2019年   2585篇
  2018年   3085篇
  2017年   3330篇
  2016年   3384篇
  2015年   2312篇
  2014年   3182篇
  2013年   27390篇
  2012年   2369篇
  2011年   2724篇
  2010年   2333篇
  2009年   2616篇
  2008年   2370篇
  2007年   2116篇
  2006年   2351篇
  2005年   2348篇
  2004年   3041篇
  2003年   2356篇
  2002年   2175篇
  2001年   2024篇
  2000年   1712篇
  1999年   1578篇
  1998年   1458篇
  1997年   1524篇
  1996年   1709篇
  1995年   1468篇
  1994年   1471篇
  1993年   1479篇
  1992年   1509篇
  1991年   1430篇
  1990年   1420篇
  1989年   1352篇
  1988年   1199篇
  1987年   1148篇
  1986年   1176篇
  1985年   1430篇
  1984年   1289篇
  1983年   1301篇
  1982年   1275篇
  1981年   1187篇
  1980年   1169篇
  1979年   1297篇
  1978年   1222篇
  1977年   1123篇
  1976年   1006篇
  1975年   826篇
  1974年   823篇
  1973年   787篇
  1971年   654篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Data from surveys of parents of students in Russian schools of various types in the years 2006 to 2011 show a high level of desire to invest in their children's education. There has been a high degree of stability in aspirations and investment in spite of the economic problems caused by global recession.  相似文献   
993.
994.
995.
Using a participatory learning approach, we report on the delivery and evaluation of a climate change and risk assessment tool to help manage water risks within the agricultural sector. Post-graduate water-professional students from a range of countries, from both developed and emerging economies were involved in using this tool. Our approach included participative learning tools – group discussion, software, and risk matrices. The materials developed met the needs of the students, allowing these students to incorporate their learning and adapt the package of materials for use in their home countries. Analysis of evaluations show that the tools and materials are particularly useful and emphasizes the need for sound learning materials and tools, funding to deliver training, and policy support to accelerate education and adoption of authentic climate change adaptation practices. The expected benefits for water professionals about climate change will be translated into improved socioeconomic and environmental outcomes if adopted.  相似文献   
996.
997.
Counselors (N = 911) reported the research skills needed for practice and subsequent research training needs. Findings indicate that counselors have a high need for research skills at work, but training needs differ significantly by counselor type. Recommendations include increasing emphasis on single‐case design, survey design, and widely available data analysis tools.  相似文献   
998.
999.
Objective: To analyze the possible dose-response association between components of sports participation (intensity, volume and previous engagement) and 4-year mortality rates among Brazilian adults.

Methods: 679 males and females (mean age among men = 66.7 ± 9.3 years old and mean age among women = 64.8 ± 8.9 years old) composed the study sample. Sports participation was assessed using Baecke’s questionnaire, which considers intensity, duration and previous engagement. Medical records were used to identify the cause of the death. Cox regression analysis was performed to determine the independent associations of exercise components and mortality.

Results: Participants that reported exercising at moderate-vigorous intensity (Moderate/vigorous: 4.1% versus None/light: 10.3% [p-value = 0.012]; HR = 0.42 [0.1 to 0.94)] and for more than four months (≥4 months: 5.3% versus <4 months: 10.2% [p-value = 0.038]; HR = 0.47 [0.24 to 0.94]) had lower mortality risk. The percentage of survival according to all-cause mortality was significantly higher for participants engaged in sports at moderate-vigorous intensity (p-value = 0.014), as well as for those engaged in sports for periods superior than four months (p-value = 0.036).

Conclusion: We found higher percentage of survival among adults engaged in sports at moderate-vigorous intensity and with at least four months of previous engagement.  相似文献   

1000.
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