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   127387篇
  免费   5864篇
  国内免费   1023篇
耳鼻咽喉   1976篇
儿科学   6468篇
妇产科学   2764篇
基础医学   10741篇
口腔科学   5158篇
临床医学   9346篇
内科学   27030篇
皮肤病学   3827篇
神经病学   8077篇
特种医学   6146篇
外国民族医学   2篇
外科学   28169篇
综合类   4258篇
预防医学   6631篇
眼科学   2502篇
药学   6093篇
  12篇
中国医学   1505篇
肿瘤学   3569篇
  2023年   3691篇
  2022年   4559篇
  2021年   6279篇
  2020年   4817篇
  2019年   11959篇
  2018年   9053篇
  2017年   4681篇
  2016年   1799篇
  2015年   2381篇
  2014年   3377篇
  2013年   2137篇
  2012年   1554篇
  2011年   5207篇
  2010年   2110篇
  2009年   2344篇
  2008年   2449篇
  2007年   1990篇
  2006年   1709篇
  2005年   2159篇
  2004年   2092篇
  2003年   1568篇
  2002年   2000篇
  2001年   2276篇
  2000年   3298篇
  1999年   3637篇
  1998年   3408篇
  1997年   2369篇
  1996年   1664篇
  1995年   1212篇
  1994年   1248篇
  1993年   906篇
  1992年   902篇
  1991年   825篇
  1990年   812篇
  1989年   595篇
  1988年   673篇
  1987年   450篇
  1985年   2879篇
  1984年   4160篇
  1983年   2983篇
  1982年   2956篇
  1981年   2755篇
  1980年   2460篇
  1979年   2224篇
  1978年   1836篇
  1977年   1593篇
  1976年   1717篇
  1975年   1446篇
  1974年   1283篇
  1973年   1212篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
41.
BackgroundLymph node recurrences (LNR) from colorectal cancer (CRC) still represent a therapeutic challenge, as standardized recommendations have yet to be established. The aim of this study was to analyze short- and long-term oncological outcomes following resection of LNR from CRC.MethodsAll patients with previously resected CRC who underwent histopathologically confirmed LNR resection in 3 tertiary referral centers between 2010 and 2017 were reviewed. Short- and long-term outcomes were analyzed, mainly recurrence-free and overall survival. Further recurrences following LNR resection were also analyzed.ResultsOverall, 18 patients were included. Primary CRC was left-sided in 16 (89%) patients, staged T3-4 in 15 (83%), N+ in 14 (78%) and presented with synchronous metastases in 8 (43%). Median time interval between primary CRC and LNR resections was 31 months. Performed lymphadenectomies were aortocaval (n = 10), pelvic (n = 7), in hepatic pedicle (n = 3) and mesenteric (n = 1). Four patients had associated liver metastases resection. Three (17%) presented with postoperative complications, of which one Clavien-Dindo 3. Fourteen (78%) patients presented with further recurrences after a mean delay of 9 months, with 36% of patients presenting with early (<6 months) recurrence. Five (36%) patients could undergo secondary recurrence resection and 3 (21%) patients radiotherapy. Median overall survival following LNR resection reached 44 months.ConclusionsCurrent results suggest that LNR resection is feasible and associated with improved survival, in selected patients. Longer time interval between primary CRC resection and LNR occurrence appeared to be a favorable prognostic factor whereas multisite recurrence appeared to be associated with impaired long-term survival.  相似文献   
42.
43.
44.
45.
46.
47.
48.
49.
《Vaccine》2020,38(45):7118-7128
IntroductionToward the Global Vaccine Action Plan 2020 goal, almost 90% of countries have established a National Immunization Technical Advisory Group (NITAG). However, little is known about NITAG's contributions to governance.MethodsIn 2017–2018, a two-step, qualitative retrospective study was conducted. Jordan (JO), Argentina (AR), and South Africa (SA) were selected owing to government-financed NITAGs from middle-income countries (MICs), geographic diversity, and a vaccine introduction with NITAG support. Country case studies were developed, collecting data through desk review and face-to-face key informant interviews (KIIs) from Ministry of Health (MoH) and NITAG. Case studies were analyzed together, to assess governance applying the European Observatory on Health Systems and Policies framework focusing on transparency, accountability, participation, integrity, and policy capacity (TAPIC).ResultsDocument review and 53 KII (22 AR, 20 SA, 11 JO) showed NITAGs played a pivotal role as advisors promoting a culture of evidence-informed policies. NITAGs strengthened governance, although practices varied among countries. Meetings were conducted behind-closed-doors, participation restricted to members, only in one country agendas, and recommendations were public (AR). To increase participation, policy capacity, and transparency, countries considered adding experts in communications, advocacy, and economics. AR and SA contemplated including community members. NITAGs functioned autonomously from the government, with no established internal or external monitoring or supervision. NITAG meeting minutes allowed the review of integrity, adherence to terms of reference, standard operating procedures, and conflict of interest (CoI). For the most part, NITAGs abided by their mandates. Significant issues were related to the level of MoH support and oversight of CoI declaration and documentation.ConclusionsSystematically implementing governance approaches could improve processes, better tailor policies, and implementation. The long-term survival and resilience of NITAGs in these countries showed they play a significant role in strengthening governance. Lessons learned could be useful to those promoting country-driven evidence-informed decision-making.  相似文献   
50.
  1. Download : Download high-res image (232KB)
  2. Download : Download full-size image
  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