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   223680篇
  免费   20221篇
  国内免费   4856篇
耳鼻咽喉   3269篇
儿科学   4210篇
妇产科学   3679篇
基础医学   17111篇
口腔科学   7298篇
临床医学   20227篇
内科学   21471篇
皮肤病学   2652篇
神经病学   11947篇
特种医学   5811篇
外国民族医学   12篇
外科学   20630篇
综合类   35182篇
现状与发展   5篇
一般理论   27篇
预防医学   28131篇
眼科学   2100篇
药学   28340篇
  336篇
中国医学   26887篇
肿瘤学   9432篇
  2023年   4255篇
  2022年   6530篇
  2021年   10219篇
  2020年   10565篇
  2019年   12006篇
  2018年   10732篇
  2017年   9374篇
  2016年   8354篇
  2015年   7819篇
  2014年   15452篇
  2013年   16473篇
  2012年   13885篇
  2011年   14824篇
  2010年   11887篇
  2009年   10229篇
  2008年   9476篇
  2007年   9594篇
  2006年   8145篇
  2005年   6921篇
  2004年   5729篇
  2003年   5163篇
  2002年   3915篇
  2001年   3309篇
  2000年   2893篇
  1999年   2336篇
  1998年   1766篇
  1997年   1612篇
  1996年   1327篇
  1995年   1366篇
  1994年   1229篇
  1993年   1132篇
  1992年   1048篇
  1991年   938篇
  1990年   825篇
  1989年   785篇
  1988年   742篇
  1987年   638篇
  1986年   605篇
  1985年   1899篇
  1984年   2161篇
  1983年   1357篇
  1982年   1792篇
  1981年   1238篇
  1980年   1078篇
  1979年   955篇
  1978年   796篇
  1977年   606篇
  1976年   738篇
  1975年   519篇
  1974年   429篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
我国奶牛养殖规模不断扩大,奶业产值比重逐步提高,给奶牛疫病防治带来巨大压力。奶牛乳房炎及细菌性肺炎等呼吸系统疾病和细菌性肠炎等消化系统疾病最为常见,抗菌药物的使用成为主要防治手段。但抗菌药物的不当使用易使细菌产生耐药性,增加临床治疗的成本和难度,危害我国奶牛产业发展。本文对截至2021年7月我国和美国、英国、日本、欧盟批准用于奶牛的抗菌药物产品进行整理、统计与分析,包括抗菌药物的分类、剂型以及适应证等,旨在为我国奶牛用抗菌药物管理、合理用药和新兽药开发提供参考。  相似文献   
3.
目的:探讨基于虚拟教研室的公共卫生安全素养培育课程构建及实践。方法:选取某医学院校专科护理专业学生(护生)为研究对象,将护理1班45人作为试验组,将护理2班43人作为对照组,对照组对公共卫生安全知识实施线上与线下的常规教学,试验组实施基于虚拟教研室的公共卫生安全素养培育课程。比较两组护生内容掌握情况及学习满意度。结果:试验组护生的学习成绩明显高于对照组(P<0.01),试验组护生对教学的满意度为95.6%(43/45),明显高于对照组(P<0.05)。结论:基于虚拟教研室的公共卫生安全素养培育课程构建既可以广泛促进不同专业教师进行教学研究交流,全面提高教师教书育人能力,又可以使护生在学习过程中接触不同专业、不同领域的知识与技能,注重护生主体作用,提高学习效果和学习满意度。  相似文献   
4.
目的 基于《国际功能、残疾和健康分类》(ICF)构建智力和发展性残疾儿童青少年身体活动效益系统综述的范畴和PICO架构,探讨智力和发展性残疾儿童和青少年参加身体活动的健康效益。  相似文献   
5.
【目的】 对术语使用情况进行调研,找出术语使用不规范的问题,为提升我国科技期刊术语规范化水平、推进科技期刊高质量发展提供依据。【方法】 采用回顾性调查方法,选择18种科技期刊2020年全年刊出的所有文章,调查其中术语使用差错情况。【结果】 术语相关差错主要涉及术语使用规范问题、术语编校规范问题及专有名词术语规范问题,具体差错类型比较多样化,不利于期刊质量及影响力的提升,应引起论文作者及期刊工作者的高度重视。术语相关差错中,术语使用规范问题最为突出;术语使用规范问题的各种类型中,术语形音义相近而误的现象最为突出。【结论】 我国科技期刊术语规范化水平有待提升,需要引起重视。  相似文献   
6.
《Vaccine》2022,40(52):7604-7612
Background and ObjectiveVaccine uptake during pregnancy remains low. Our objectives were to describe 1) development and adaptation of a clinician communication training intervention for maternal immunizations and 2) obstetrics and gynecology (ob-gyn) clinician and staff perspectives on the intervention and fit for the prenatal care context.MethodsDesign of the Motivational Interviewing for Maternal Immunizations (MI4MI) intervention was based on similar communication training interventions for pediatric settings and included presumptive initiation of vaccine recommendations (“You’re due for two vaccines today”) combined with motivational interviewing (MI) for hesitant patients. Interviews and focus group discussions were conducted with ob-gyn clinicians and staff in five Colorado clinics including settings with obstetric physicians, certified nurse midwives (CNMs), and clinician-trainees. Participants were asked about adapting training to the ob-gyn setting and their implementation experiences. Feedback was incorporated through iterative changes to training components.ResultsInterview and focus group discussion results from participants before (n = 3), during (n = 11) and after (n = 25) implementation guided intervention development and adaptation. Three virtual, asynchronous training components were created: a video and two interactive modules. This virtual format was favored due to challenges attending group meetings; however, participants noted opportunities to practice skills through role-play were lacking. Training modules were adapted to include common challenging vaccine conversations and live-action videos. Participants liked interactive training components and use of adult learning strategies. Some participants initially resisted the presumptive approach but later found it useful after applying it in their practices. Overall, participants reported that MI4MI training fit well with the prenatal context and recommended more inclusion of non-clinician staff.ConclusionsMI4MI training was viewed as relevant and useful for ob-gyn clinicians and staff. Suggestions included making training more interactive, and including more complex scenarios and non-clinician staff.  相似文献   
7.
8.
With a 5.3% of the global population involved, hepatitis B virus (HBV) is a major public health challenge requiring an urgent response. After a possible acute phase, the natural history of HBV infection can progress in chronicity. Patients with overt or occult HBV infection can undergo HBV reactivation (HBVr) in course of immunosuppressive treatments that, apart from oncological and hem-atological diseases, are also used in rheumatologic, gastrointestinal, neurological and dermatological settings, as well as to treat severe acute respiratory syndrome coronavirus 2 infection. The risk of HBV reactivation is related to the immune status of the patient and the baseline HBV infection condition. The aim of the present paper is to investigate the risk of HBVr in those not oncological settings in order to suggest strategies for preventing and treating this occurrence. The main studies about HBVr for patients with occult hepatitis B infection and chronic HBV infection affected by non-oncologic diseases eligible for immunosuppressive treatment have been analyzed. The occurrence of this challenging event can be reduced screening the population eligible for immunosuppressant to assess the best strategies according to any virological status. Further prospective studies are needed to increase data on the risk of HBVr related to newer immunomodulant agents employed in non-oncological setting.  相似文献   
9.
AimTo evaluate the surgery program strategy adopted in an adult otorhinolaryngology and head and neck surgery department in an area badly affected by the Covid-19 epidemic peak. The main objective was to analyze the reasons for not cancelling surgeries and the postoperative course of operated patients. The secondary objective was to assess the situation of postponed patients.Material and MethodsA single-center observational study carried out during the COVID-19 period in France included 124 patients scheduled for surgery during the period March 21-May 20, 2020. The number and nature of operations, both performed and postponed, were reviewed.ResultsA total of 54.0% patients were operated on during the COVID period and 46.0% were postponed. Operations were maintained in urgent or semi-urgent cases. The operated patients did not show any signs of infection during their hospital stay. A total of 29.8% of postponed patients were lost to follow-up and 49.1% were rescheduled.ConclusionThe application of national and international recommendations minimized the risk of loss of chance for operated patients without increasing the risk of contamination. The postponement of canceled operations resulted in considerable loss to follow-up. Intensified follow-up is necessary for these patients.  相似文献   
10.
BackgroundRecent guidelines for the treatment of moderate or severe ischemic mitral regurgitation (IMR) in patients undergoing coronary artery bypass grafting (CABG) have changed. This study assessed the real-world impact of changing guidelines on the management of IMR during CABG over time. We hypothesized that the utilization of mitral valve repair for IMR would decrease over time, whereas mitral valve replacement for severe IMR would increase.MethodsPatients undergoing CABG in a statewide collaborative database (2011-2020) were stratified by severity of IMR. Trends in mitral valve repair or replacement were evaluated. To account for differences of the patients, propensity score–matched analyses were used to compare patients with and without mitral intervention.ResultsA total of 11,676 patients met inclusion criteria, including 1355 (11.6%) with moderate IMR and 390 (3.3%) with severe IMR. The proportion of patients undergoing mitral intervention for moderate IMR decreased over time (2011, 17.7%; 2020, 7.5%; Ptrend = .001), whereas mitral replacement for severe IMR remained stable (2011, 11.1%; 2020, 13.3%; Ptrend = .14). Major morbidity was higher for patients with moderate IMR who underwent mitral intervention (29.1% vs 19.9%; P = .005). In a propensity analysis of 249 well-matched pairs, there was no difference in major morbidity (29.3% with mitral intervention vs 23.7% without; P = .16) or operative mortality (1.2% vs 2.4%; P = .5).ConclusionsConsistent with recent guideline updates, patients with moderate IMR were less likely to undergo mitral repair. However, the rate of replacement for severe IMR did not change. Mitral intervention during CABG did not increase operative mortality or morbidity.  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