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   425948篇
  免费   29754篇
  国内免费   11754篇
耳鼻咽喉   4404篇
儿科学   11079篇
妇产科学   7688篇
基础医学   42685篇
口腔科学   8917篇
临床医学   43800篇
内科学   61967篇
皮肤病学   5885篇
神经病学   23566篇
特种医学   9622篇
外国民族医学   54篇
外科学   41225篇
综合类   64691篇
现状与发展   31篇
一般理论   29篇
预防医学   40375篇
眼科学   6230篇
药学   41418篇
  399篇
中国医学   34222篇
肿瘤学   19169篇
  2023年   6094篇
  2022年   11010篇
  2021年   15829篇
  2020年   14697篇
  2019年   20402篇
  2018年   18098篇
  2017年   15263篇
  2016年   13281篇
  2015年   13013篇
  2014年   25256篇
  2013年   27330篇
  2012年   24113篇
  2011年   26009篇
  2010年   20957篇
  2009年   19461篇
  2008年   19171篇
  2007年   19401篇
  2006年   17136篇
  2005年   14911篇
  2004年   12220篇
  2003年   10684篇
  2002年   8480篇
  2001年   7609篇
  2000年   6263篇
  1999年   5461篇
  1998年   4589篇
  1997年   4208篇
  1996年   3639篇
  1995年   3500篇
  1994年   3265篇
  1993年   2655篇
  1992年   2597篇
  1991年   2216篇
  1990年   1965篇
  1989年   1743篇
  1988年   1634篇
  1987年   1410篇
  1985年   4182篇
  1984年   5167篇
  1983年   3598篇
  1982年   4098篇
  1981年   3784篇
  1980年   3387篇
  1979年   3103篇
  1978年   2665篇
  1977年   2022篇
  1976年   2271篇
  1975年   1722篇
  1974年   1519篇
  1973年   1335篇
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
81.
ObjectiveHospitalization-associated disability [HAD, ie, the loss of ability to perform ≥1 basic activities of daily living (ADLs) independently at discharge] is a frequent condition among older patients. The present study assessed whether a simple inpatient exercise program decreases HAD incidence in acutely hospitalized very old patients.DesignIn this randomized controlled trial (Activity in Geriatric Acute Care) participants were assigned to a control or intervention group and were assessed at baseline, admission, discharge, and 3 months thereafter.Setting and ParticipantsIn total, 268 patients (mean age 88 years, range 75–102) admitted to an acute care for older patients unit of a public hospital were randomized to a control (n = 125) or intervention (exercise) group (n = 143).MethodsBoth groups received usual care, and patients in the intervention group also performed simple supervised exercises (walking and rising from a chair, for a total duration of ∼20 minutes/day). We measured ADL function (Katz index) and incident HAD at discharge and after 3 months (primary outcome) and Short Physical Performance Battery, ambulatory capacity, number of falls, rehospitalization, and death during a 3-month follow-up (secondary outcomes).ResultsMedian duration of hospitalization was 7 days (interquartile range 4 days). The intervention group had a lower risk of HAD with reference to both baseline [odds ratio (OR) 0.36; 95% confidence interval (CI) 0.17–0.76, P = .007] and admission (OR 0.29; 95% CI 0.10–0.89, P = .030). A trend toward an improved ADL function at discharge vs admission was found in the intervention group compared with controls (OR 0.32; 95% CI ‒0.04 to 0.68; P = .083). No between-group differences were noted for the other endpoints (all P > .05).Conclusion and ImplicationsA simple inpatient exercise program decreases risk of HAD in acutely hospitalized, very old patients.  相似文献   
82.
《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   
83.
  1. Download : Download high-res image (232KB)
  2. Download : Download full-size image
  相似文献   
84.
85.
脑卒中患者在面对复杂的治疗期、漫长的康复期及难以预测的病情变化时容易产生对疾病或疾病进展的恐惧。恐惧疾病进展会损害脑卒中患者的身心健康和社会功能,最终影响患者的康复和预后。从恐惧疾病进展的定义、测量工具、国内外研究现状及影响因素几个方面进行综述,为临床护理人员深入了解脑卒中患者恐惧疾病进展现状、开展相关护理实践和临床研究提供依据。  相似文献   
86.
This paper describes country-wide special measures undertaken for interventional radiology staff during the current coronavirus disease 2019 (COVID-19) pandemic. Although each interventional radiology service around the world faces unique challenges, the principles outlined in this article will be useful when designing or strengthening individual practices and integrating them within wider hospital and national measures. Moving beyond the current outbreak, these measures will be useful for any future infectious diseases which are likely to arise.  相似文献   
87.
88.

Background

Resistin is an immunometabolic mediator that is elevated in several inflammatory disorders. A ligand for Toll-like receptor 4, resistin modulates the recruitment and activation of myeloid cells, notably neutrophils. Neutrophils are major drivers of cystic fibrosis (CF) lung disease, in part due to the release of human neutrophil elastase- and myeloperoxidase-rich primary granules, leading to tissue damage. Here we assessed the relationship of resistin to CF lung disease.

Methods

Resistin levels were measured in plasma and sputum from three retrospective CF cohorts spanning a wide range of disease. We also assessed the ability of neutrophils to secrete resistin upon activation in vitro. Finally, we constructed a multivariate model assessing the relationship between resistin levels and lung function.

Results

Plasma resistin levels were only marginally higher in CF than in healthy control subjects. By contrast, sputum resistin levels were very high in CF, reaching 50–100 fold higher levels than in plasma. Among CF patients, higher plasma resistin levels were associated with allergic bronchopulmonary aspergillosis, and higher sputum resistin levels were associated with CF-related diabetes. Mechanistically, in vitro release of neutrophil primary granules was concomitant with resistin secretion. Overall, sputum resistin levels were negatively correlated with CF lung function, independently of other variables (age, sex, and genotype).

Conclusions

Our data establish relationships between resistin levels in the plasma and sputum of CF patients that correlate with disease status, and identify resistin as a novel mechanistic link between neutrophilic inflammation and lung disease in CF.  相似文献   
89.
90.
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