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   2882篇
  免费   74篇
  国内免费   55篇
教育   1924篇
科学研究   453篇
各国文化   19篇
体育   276篇
综合类   223篇
文化理论   4篇
信息传播   112篇
  2024年   2篇
  2023年   42篇
  2022年   103篇
  2021年   240篇
  2020年   209篇
  2019年   50篇
  2018年   29篇
  2017年   18篇
  2016年   29篇
  2015年   57篇
  2014年   128篇
  2013年   142篇
  2012年   185篇
  2011年   224篇
  2010年   172篇
  2009年   164篇
  2008年   182篇
  2007年   170篇
  2006年   157篇
  2005年   149篇
  2004年   113篇
  2003年   108篇
  2002年   104篇
  2001年   55篇
  2000年   40篇
  1999年   27篇
  1998年   19篇
  1997年   16篇
  1996年   15篇
  1995年   8篇
  1994年   10篇
  1993年   9篇
  1992年   6篇
  1991年   4篇
  1990年   3篇
  1989年   5篇
  1985年   3篇
  1984年   2篇
  1982年   6篇
  1981年   3篇
  1979年   1篇
  1978年   1篇
  1977年   1篇
排序方式: 共有3011条查询结果,搜索用时 187 毫秒
1.
The current Coronavirus disease (Covid-19) pandemic has spread to about 220 countries of the world and has resulted in a significant number of deaths globally. Infections are still on the rise, and the impact on the global death rate could be devastating. There are fears over the likely impact of a large number of deaths on body sourcing and handling of cadavers for teaching and research. Historically, epidemics come with several challenges and have often led to some level of negligence of ethical practices and health and safety regulations associated with body sourcing and handling. The authors highlighted some emerging problems in this article, focusing on Africa and Nigeria in particular. These problems include a higher risk of coronavirus exposure for body handlers, shortage of cadavers for teaching and learning, a lack of standard regulations leading to unethical body sourcing and handling, and a lack of monitoring and collaboration needed for a well-coordinated Covid-19 pandemic response strategy. If these issues are ignored, the previous gains made in anatomical ethical practices may be destroyed. Some useful recommendations for policymaking geared toward prevention or curtailing these emerging issues have been instilled in this article.  相似文献   
2.
The COVID-19 outbreak has had a profound impact on education worldwide. As a result of the educational institutions closures, it is likely that the impact on special education would be more detrimental since special education population becomes more vulnerable in the aftermath of an outbreak. In the scope of this study, a researcher created survey was used to examine educators’ teaching experiences and their perceptions about the impact of COVID-19 outbreak on special education students. The sample included 215 educators working in the Special Education and Rehabilitation Centers (SERCs) in Turkey. Results indicated that a large majority of the SERCs were not able to continue their education during the COVID-19 outbreak. In addition, there was a difference in educators’ experiences by their educational practices (normal weekly schedule, reduced schedule, most of the educational activities are suspended, and all of the educational activities are suspended). Perceived level of COVID-19 outbreak impact on special education students were found to be significantly higher for autism spectrum disorders, intellectual disabilities, attention deficit and hyperactivity disorders, visual impairments, hearing impairments, specific learning disabilities and gifted students, respectively. The conclusion highlights the need of global collaboration, disaster preparation and management for students with special needs.  相似文献   
3.
李楠  张超  路璐  邹沐宏 《图书情报工作》2020,64(15):151-156
[目的/意义] 以中国科学院文献情报中心"中国科讯"为例,分析专业图书馆应急科学传播服务的举措及成效,为应急事件下专业图书馆科学传播服务提供借鉴。[方法/过程] 梳理新冠肺炎疫情期间"中国科讯"微信公众号推送的服务内容,从日均用户增长和阅读量分析用户对不同类型内容的关注程度,提出应急科学传播服务的思考。[结果/结论] 疫情期间,"中国科讯"日均用户增长明显,电子资源保障类内容阅读量最高,其次为新冠病毒科技攻关进展相关内容、科普类直播和信息素养教育直播观看人数达到数万人。应急事件下,专业图书馆应加强特色服务的宣传、加强信息甄选和审核机制,重大公共卫生事件下应急科学传播工作预案缺失也需引起重视。  相似文献   
4.
This paper uses a calibrated “pedagogical production function” model to estimate the potential long-term losses to children’s learning from the temporary shock of Covid-19 related school closures. It then models possible gains from two mitigation strategies. Without mitigation, children could lose more than a full year’s worth of learning from a three-month school closure because they will be behind the curriculum when they re-enter school and will fall further behind as time goes on. Remediation when children return to school reduces the long-term learning loss by half, but still leaves children more than half a year behind where they would have been with no shock. Remediation combined with long-term reorientation of curriculum to align with children’s learning levels fully mitigates the long-term learning loss due to the shock and surpasses the learning in the counterfactual of no shock by more than a full year’s worth of learning. Systems need to begin planning now for remediation programmes, and as they do so they should build programmes and train teachers in ways that can continue to produce benefits beyond the period immediately following reopening.  相似文献   
5.
Genetic variation in the angiotensin II type 1 receptor (AT1R) has an important effect on the outcome of acute coronary syndrome (ACS) initiated treatment with captopril. This study aims to investigate the impact of genetic polymorphism of AT1R (rs5186 and rs275651) on the ACS outcome in Iraqi patients treated with captopril. A total of 250 Iraqi individuals with ACS were included in this case—control study and they were divided into two study groups; Study group 1 included 125 participants who were prescribed captopril, 25 mg twice daily and study group 2 included 125 participants who received no captopril as part of their ACS treatment (control study). The AT1R gene (rs5186) CC genotype was found to be associated with ST-elevation myocardial infarction (STEMI) (Odd’s ratio (O.R) = 1.2, P = 0.7), while AC was associated with Non-ST-elevation myocardial infarction (NSTEMI) and unstable angina (UA) (O.R = 1.2, P = 0.8). AC genotype is more prone to have Percutaneous coronary intervention (PCI) after ACS attack (O.R = 1.2, P = 0.6). CC genotype had a risk to get less improvement (O.R = 1.6, P = 0.5), so might require higher doses of captopril during acute coronary insult. The AT1R gene (rs275651) AA genotype was associated with UA (O.R = 1.3, P = 0.9). AA and AT genotypes were more prone to have PCI after ACS attack (O.R = 3.9 P = 0.2, O.R = 3.5, P = 0.3 respectively) and thus requiring higher doses of captopril. We conclude that the AT1R rs5186, rs275651 genetic polymorphisms might partially affect the clinical outcome of ACS patients treated with captopril and might have captopril resistance which requires higher doses.  相似文献   
6.
7.
采用文献资料法和灰色关联度分析法,对我国优秀男子十项全能运动员齐海峰1999-2002年十项全能的比赛成绩进行统计与分析,运用GM(1,N)动态协调模型对其在总成绩不断提高的各个阶段诸因素间相互联系、相互影响的辩证发展关系进行多方位、多层次研究。结果表明:100米跑、铅球和跳远是影响齐海峰专项成绩的关键因素,其关联度分别为0.8928、0.7443和0.7571,研究还发现,齐海峰在成绩提高的每一个阶段中,系统处于不稳定和非协调发展,其中速度和速度——力量性项目落后是导致系统不稳定和非协调发展的主要因素。  相似文献   
8.
本文在宋人笔记小说中发现九世纪中叶非敷合流例一则,从而佐证了王力先生在论述唇齿音产生时间的推论.  相似文献   
9.
近两届冬奥会女子自由式滑雪空中技巧比较研究   总被引:4,自引:0,他引:4  
通过对 1998年第 18届冬奥会与 2 0 0 2年第 19届冬奥会女子自由式滑雪空中技巧比赛的动作难度、动作质量及实力格局的比较研究表明 :4年来世界女子自由式滑雪空中技巧项目的动作难度与动作质量呈显著同步提高之势 ,揭示了该项目的发展方向 ;从上届冬奥会的美、中、瑞、乌 4强到本届冬奥会的澳、加、俄、中 4强 ,世界女子自由式滑雪空中技巧项目的实力格局发生了变化 ;以李妮娜为代表的我国年轻运动员已跻身世界优秀运动员行列  相似文献   
10.
二次曲线的三种分类方法分析   总被引:1,自引:0,他引:1  
分析了二次曲线在仿射几何、射影几何和欧氏几何中的分类方法,给出了3种方法之间的联系与区别。  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