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   57109篇
  免费   4634篇
  国内免费   126篇
耳鼻咽喉   453篇
儿科学   2288篇
妇产科学   1652篇
基础医学   7507篇
口腔科学   626篇
临床医学   7460篇
内科学   11140篇
皮肤病学   934篇
神经病学   5528篇
特种医学   1279篇
外国民族医学   38篇
外科学   5638篇
综合类   789篇
一般理论   104篇
预防医学   8153篇
眼科学   788篇
药学   3091篇
中国医学   89篇
肿瘤学   4312篇
  2023年   497篇
  2022年   656篇
  2021年   1640篇
  2020年   996篇
  2019年   1548篇
  2018年   1823篇
  2017年   1330篇
  2016年   1402篇
  2015年   1502篇
  2014年   2088篇
  2013年   3052篇
  2012年   4344篇
  2011年   4420篇
  2010年   2395篇
  2009年   2059篇
  2008年   3732篇
  2007年   3772篇
  2006年   3503篇
  2005年   3422篇
  2004年   3116篇
  2003年   2778篇
  2002年   2582篇
  2001年   598篇
  2000年   482篇
  1999年   534篇
  1998年   552篇
  1997年   432篇
  1996年   362篇
  1995年   384篇
  1994年   313篇
  1993年   300篇
  1992年   360篇
  1991年   345篇
  1990年   309篇
  1989年   261篇
  1988年   296篇
  1987年   237篇
  1986年   259篇
  1985年   252篇
  1984年   214篇
  1983年   201篇
  1982年   175篇
  1981年   214篇
  1980年   154篇
  1979年   137篇
  1978年   141篇
  1976年   118篇
  1975年   112篇
  1974年   111篇
  1973年   141篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
Emergency Medicine staff in Australia and New Zealand are at the forefront of the healthcare response to COVID‐19. This article describes a well‐being plan for ED staff that has been devised to mitigate against the negative psychological impact of the COVID‐19 pandemic.  相似文献   
4.

Objectives

Expedient extubation after cardiac surgery has been associated with improved outcomes, leading to postoperative extubation frequently during overnight hours. However, recent evidence in a mixed medical-surgical intensive care unit population demonstrated worse outcomes with overnight extubation. This study investigated the impact of overnight extubation in a statewide, multicenter Society of Thoracic Surgeons database.

Methods

Records from 39,812 patients undergoing coronary artery bypass grafting or valve operations (2008-2016) and extubated within 24 hours were stratified according to extubation time between 06:00 and 18:00 (day) or between 18:00 and 6:00 (overnight). Outcomes including reintubation, mortality, and composite morbidity-mortality were evaluated using hierarchical regression models adjusted for Society of Thoracic Surgeons predictive risk scores. To further analyze extubation during the night, a subanalysis stratified patients into 3 groups: 06:00 to 18:00, 18:00 to 24:00, and 24:00 to 06:00.

Results

A total of 20,758 patients were extubated overnight (52.1%) and were slightly older (median age 66 vs 65 years, P < .001) with a longer duration of ventilation (4 vs 7 hours, P < .001). Day and overnight extubation were associated with equivalent operative mortality (1.7% vs 1.7%, P = .880), reintubation (3.7% vs 3.4%, P = .141), and composite morbidity-mortality (8.2% vs 8.0%, P = .314). After risk adjustment, overnight extubation was not associated with any difference in reintubation, mortality, or composite morbidity-mortality. On subanalysis, those extubated between 24:00 and 06:00 exhibited increased composite morbidity-mortality (odds ratio, 1.18; P = .001) but no difference in reintubation or mortality.

Conclusions

Extubation overnight was not associated with increased mortality or reintubation. These results suggest that in the appropriate clinical setting, it is safe to routinely extubate cardiac surgery patients overnight.  相似文献   
5.
6.
Prevalence of osteoporosis is more than 50% in older adults, yet current clinical methods for diagnosis that rely on areal bone mineral density (aBMD) fail to detect most individuals who have a fragility fracture. Bone fragility can manifest in different forms, and a “one-size-fits-all” approach to diagnosis and management of osteoporosis may not be suitable. High-resolution peripheral quantitative computed tomography (HR-pQCT) provides additive information by capturing information about volumetric density and microarchitecture, but interpretation is challenging because of the complex interactions between the numerous properties measured. In this study, we propose that there are common combinations of bone properties, referred to as phenotypes, that are predisposed to different levels of fracture risk. Using HR-pQCT data from a multinational cohort (n = 5873, 71% female) between 40 and 96 years of age, we employed fuzzy c-means clustering, an unsupervised machine-learning method, to identify phenotypes of bone microarchitecture. Three clusters were identified, and using partial correlation analysis of HR-pQCT parameters, we characterized the clusters as low density, low volume, and healthy bone phenotypes. Most males were associated with the healthy bone phenotype, whereas females were more often associated with the low volume or low density bone phenotypes. Each phenotype had a significantly different cumulative hazard of major osteoporotic fracture (MOF) and of any incident osteoporotic fracture (p < 0.05). After adjustment for covariates (cohort, sex, and age), the low density followed by the low volume phenotype had the highest association with MOF (hazard ratio = 2.96 and 2.35, respectively), and significant associations were maintained when additionally adjusted for femoral neck aBMD (hazard ratio = 1.69 and 1.90, respectively). Further, within each phenotype, different imaging biomarkers of fracture were identified. These findings suggest that osteoporotic fracture risk is associated with bone phenotypes that capture key features of bone deterioration that are not distinguishable by aBMD. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
7.
8.
9.
10.
Epidermolysis bullosa simplex (EBS) is a skin fragility disorder resulting from mutations of structural proteins in the epidermis. We provide a brief report of long‐term survival and reproduction in a mother with EBS due to keratin 5 (KRT5) c.1429G > A (p.E477K) mutation, which causes a particularly severe form of the disease.  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