首页 | 官方网站   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   2380篇
  免费   95篇
  国内免费   12篇
医药卫生   2487篇
  2024年   2篇
  2023年   11篇
  2022年   10篇
  2021年   46篇
  2020年   32篇
  2019年   39篇
  2018年   63篇
  2017年   42篇
  2016年   59篇
  2015年   58篇
  2014年   71篇
  2013年   101篇
  2012年   130篇
  2011年   174篇
  2010年   83篇
  2009年   79篇
  2008年   200篇
  2007年   213篇
  2006年   240篇
  2005年   214篇
  2004年   142篇
  2003年   138篇
  2002年   119篇
  2001年   45篇
  2000年   43篇
  1999年   34篇
  1998年   11篇
  1997年   8篇
  1996年   8篇
  1995年   8篇
  1994年   3篇
  1993年   2篇
  1992年   14篇
  1991年   12篇
  1990年   13篇
  1989年   1篇
  1988年   2篇
  1987年   1篇
  1986年   3篇
  1984年   1篇
  1982年   2篇
  1979年   1篇
  1977年   2篇
  1976年   1篇
  1973年   1篇
  1969年   1篇
  1966年   2篇
  1937年   1篇
  1934年   1篇
排序方式: 共有2487条查询结果,搜索用时 15 毫秒
21.
Making science relevant to students' lives, future careers, or societies by introducing controversial socio-scientific issues in classrooms motivates students to take more active roles in learning science. This study explored the influence of integrating two sustainability-oriented socio-scientific issues (SOS2Is) - alternative energies and nanotechnology-into the General Chemistry curriculum on 743 students' career aspirations and perceptions of science relevancy. For the presentation of topics, two learning environments on Prezi were prepared. The participants were guided to explore these learning environments that focused on pros and cons of each topic, including environmental and health hazards of technological developments. In addition, students were encouraged to link these discussions to sustainability issues in the context of the UN SDGs. The analysis of Changes in Attitude Towards the Relevancy of Science and Career Aspirations surveys indicated that the interventions improved students' perception of science relevancy and altered their career aspirations in many areas, regardless of their socioeconomic status and ethnic background. This study provides empirical evidence for the effectiveness of discussions around socio-scientific issues in changing students’ perceptions of science and career aspirations and recommends practical methods to encourage students to become global and scientifically literate citizens.  相似文献   
22.
23.
24.
25.
26.
Cancer is a major worldwide health problem and one of the leading causes of death either in developed or developing countries. Plant extracts and derivatives have always been used for various disease treatments and many anticancer agents issued from plants and vegetables are clinically recognized and used all over the world. Lycium europaeum (Solanaceae) also called “wolfberry” was known since ancient times in the Mediterranean area as a medicinal plant and used in several traditional remedies. The Lycium species capacity of reducing the incidence of cancer and also of halting or reserving the growth of cancer was reported by traditional healers. In this study, the antiproliferative capacity, protective properties, and antioxidant activity of the hydro-alcoholic fruit extract of Lycium europaeum were investigated. Results showed that Lycium extract exhibits the ability to reduce cancer cell viability, inhibits proliferation, and induces apoptosis in A549 human lung cancer cells and PC12 rat adrenal medulla cancer cells, in a concentration- and time-dependent manner. Cytotoxic effect on normal rat cerebellum granule cells was assessed to be nonsignificant. Results also showed that Lycium fruit extract protected lipids, proteins, and DNA against oxidative stress damages induced by H2O2 via scavenging reactive oxygen species.  相似文献   
27.
28.
29.
30.
Left ventricular pseudoaneurysm is a false aneurysm, which results from a left ventricle rupture contained by adherent pericardium or scar tissue. The most common etiology of left ventricular pseudoaneurysm is acute myocardial infarction but one-third of pseudoaneurysms develop following surgery. We present a case report of a patient who developed a false aneurysm of the left ventricle 2 months following surgical repair of a left ventricular aneurysm with a concomitant coronary bypass.  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-23

京公网安备 11010802026262号