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   23225篇
  免费   1710篇
  国内免费   516篇
耳鼻咽喉   110篇
儿科学   415篇
妇产科学   297篇
基础医学   2881篇
口腔科学   277篇
临床医学   3025篇
内科学   4781篇
皮肤病学   387篇
神经病学   997篇
特种医学   468篇
外国民族医学   1篇
外科学   1850篇
综合类   2121篇
现状与发展   4篇
一般理论   49篇
预防医学   4111篇
眼科学   335篇
药学   1465篇
  21篇
中国医学   688篇
肿瘤学   1168篇
  2024年   59篇
  2023年   2138篇
  2022年   3180篇
  2021年   6915篇
  2020年   4697篇
  2019年   357篇
  2018年   305篇
  2017年   252篇
  2016年   272篇
  2015年   314篇
  2014年   540篇
  2013年   525篇
  2012年   450篇
  2011年   544篇
  2010年   470篇
  2009年   477篇
  2008年   434篇
  2007年   436篇
  2006年   425篇
  2005年   340篇
  2004年   326篇
  2003年   277篇
  2002年   175篇
  2001年   175篇
  2000年   157篇
  1999年   113篇
  1998年   112篇
  1997年   82篇
  1996年   91篇
  1995年   80篇
  1994年   62篇
  1993年   73篇
  1992年   57篇
  1991年   69篇
  1990年   63篇
  1989年   53篇
  1988年   49篇
  1987年   33篇
  1986年   22篇
  1985年   53篇
  1984年   38篇
  1983年   26篇
  1982年   25篇
  1981年   23篇
  1980年   16篇
  1979年   13篇
  1977年   11篇
  1975年   10篇
  1974年   6篇
  1973年   18篇
排序方式: 共有10000条查询结果,搜索用时 328 毫秒
991.
992.
993.
994.
995.
996.
PurposeCrucial steps have been adopted by health and regulatory authorities around the world to respond to the COVID-19 pandemic. This review aims to highlight these steps by providing an overview of the regulatory approaches adopted during the onset of the pandemic, provide an assessment of observed trends, and offer some reflections and proposals to leverage learnings and opportunities from this current pandemic.MethodsDocuments and informational materials on regulating the development and management of medical products during the COVID-19 pandemic were collected and classified. These materials were sourced from official websites and press releases from health authorities and international bodies from selected markets across the globe, and covered the period between January and July 2020. Additional information to support this study was gathered through a literature review and analysis of related data available from the public domain, and was complemented with the authors' personal experience.FindingsCommunication has been vital in addressing the impact of COVID-19. A total of 1705 documents and informational materials related to health or regulatory response to the COVID-19 pandemic were gathered. Of these, 343 (around 20%) were identified as regulatory agilities. These agile approaches were classified into 3 categories, namely, where health and regulatory authorities had: (1) facilitated product management across the entire lifecycle, notably in expediting medical product use for COVID-19, ensuring the continuity of clinical trials, and addressing supply chain issues; (2) strengthened international cooperation; and (3) addressed regulatory burden with the adoption of electronic and digital tools.ImplicationsWhile many regulatory measures have been introduced temporarily as a response to the COVID-19 crisis, there are opportunities for leveraging an understanding from these approaches in order to collectively achieve more efficient regulatory systems and to mitigate and address the impact of COVID-19 and further future-proof the regulatory environment.  相似文献   
997.
998.
999.
1000.
Described for the first time in 1986, Parvovirus B19 (B19V) infection in kidney transplant recipients remains little‐known and probably underestimated. The aims of this study were to establish B19V infection frequency during the first year after kidney transplant and to determine predisposing factors and manifestations of the infection in renal transplant recipients. Sixty consecutive adult patients, transplanted less than a year before, were included in this study. B19V and other opportunistic viral infections were detected retrospectively in plasma samples collected every 15 days during the first 3 months and every month from 3 months to 1 year following the kidney transplant. Demographic characteristics, immunosuppressive treatment and biological findings were recorded on each sampling date. Six patients (10%) presented B19V viremia, while eight CMV (13.3%), seven EBV (11.7%), five HHV‐6 (8.3%), five BKV (8.3%), and two adenovirus (3.3%) infections were detected. The mean value of B19V viral load was 149 UI/ml. B19V infections were either reactivation or reinfection due to genotype two in five cases, while one case of primary infection with genotype 1 was observed. Neither risk factors nor biological consequences of B19V infection have been identified. These results rank B19V third among opportunistic viral infections occurring during the first year after a kidney transplant. With regard to this high incidence, and even if the risk factors and biological consequences of the infection should be assessed in larger studies, the question of systematic screening and follow‐up of B19V infection in kidney transplant recipients is relevant. J. Med. Virol. 85: 1115–1121, 2013. © 2013 Wiley Periodicals, Inc.  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