全文获取类型
收费全文 | 152045篇 |
免费 | 13651篇 |
国内免费 | 318篇 |
专业分类
耳鼻咽喉 | 1743篇 |
儿科学 | 5348篇 |
妇产科学 | 3883篇 |
基础医学 | 20845篇 |
口腔科学 | 2711篇 |
临床医学 | 20541篇 |
内科学 | 27239篇 |
皮肤病学 | 2338篇 |
神经病学 | 13561篇 |
特种医学 | 4111篇 |
外国民族医学 | 48篇 |
外科学 | 17757篇 |
综合类 | 2527篇 |
一般理论 | 208篇 |
预防医学 | 19660篇 |
眼科学 | 2705篇 |
药学 | 10557篇 |
1篇 | |
中国医学 | 176篇 |
肿瘤学 | 10055篇 |
出版年
2023年 | 837篇 |
2022年 | 1183篇 |
2021年 | 3037篇 |
2020年 | 1911篇 |
2019年 | 2943篇 |
2018年 | 3477篇 |
2017年 | 2542篇 |
2016年 | 2733篇 |
2015年 | 2990篇 |
2014年 | 4090篇 |
2013年 | 6326篇 |
2012年 | 8801篇 |
2011年 | 9178篇 |
2010年 | 4920篇 |
2009年 | 4498篇 |
2008年 | 8011篇 |
2007年 | 8449篇 |
2006年 | 7933篇 |
2005年 | 7895篇 |
2004年 | 7386篇 |
2003年 | 6715篇 |
2002年 | 6515篇 |
2001年 | 3178篇 |
2000年 | 3148篇 |
1999年 | 2990篇 |
1998年 | 1833篇 |
1997年 | 1459篇 |
1996年 | 1375篇 |
1995年 | 1262篇 |
1994年 | 1237篇 |
1993年 | 1124篇 |
1992年 | 2339篇 |
1991年 | 2237篇 |
1990年 | 2129篇 |
1989年 | 2037篇 |
1988年 | 1980篇 |
1987年 | 1925篇 |
1986年 | 1863篇 |
1985年 | 1862篇 |
1984年 | 1613篇 |
1983年 | 1447篇 |
1982年 | 1125篇 |
1981年 | 993篇 |
1980年 | 866篇 |
1979年 | 1339篇 |
1978年 | 1006篇 |
1977年 | 880篇 |
1976年 | 844篇 |
1974年 | 987篇 |
1973年 | 877篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Isolated patellofemoral arthritis is an increasingly recognized entity, and is usually associated with previous patellofemoral dysplasia or instability. Patellofemoral arthroplasty (PFA) has evolved significantly in recent years, both in terms of implant design and importantly in the understanding of appropriate patient selection. This review outlines the indications and investigations for PFA, provides a brief history of the development of contemporary implants, and presents the clinical outcomes for the prostheses most commonly used in the UK. In addition, it provides a detailed surgical technique for implantation of an onlay implant, with tips on how to optimize patellofemoral biomechanics and thus achieve a consistently good outcome. 相似文献
3.
4.
5.
Brittney H. Cotta Margaret F. Meagher Aaron Bradshaw Stephen T. Ryan Gerant Rivera-Sanfeliz 《Expert review of anticancer therapy》2019,19(4):301-308
Introduction: Percutaneous renal mass biopsy has evolved over the last decade with improvements on previous pitfalls including low tissue yield, high non-diagnostic rates, and complications. As understanding of tumor biology and natural history of renal cortical neoplasms has improved, percutaneous renal mass biopsy is poised to have an expanding role in an area characterized by individualized management and refined risk stratification.
Areas covered: This review summarizes the evolution of renal mass biopsy to its current state with respect to outcomes, indications, and clinical guidelines.
Expert opinion: With improved understanding of differential biological potential of renal cortical neoplasms combined with technical improvements in diagnostic yield and accuracy, utilization of renal mass biopsy is becoming an important adjunct to patient care in a broad range of clinical scenarios, including active surveillance, thermal ablation, and use of primary systemic therapy in localized and advanced settings. 相似文献
6.
Jasmine Poonian Nicola Walsham Thomas Kilner Elizabeth Bradbury Kristen Brooks Emma West 《Emergency medicine Australasia : EMA》2020,32(4):700-702
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
7.
Elizabeth D. Krebs Robert B. Hawkins J. Hunter Mehaffey Clifford E. Fonner Alan M. Speir Mohammed A. Quader Jeffrey B. Rich Leora T. Yarboro Nicholas R. Teman Gorav Ailawadi 《The Journal of thoracic and cardiovascular surgery》2019,157(4):1533-1542.e2
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8.
9.
10.
Danielle E Whittier Elizabeth J Samelson Marian T Hannan Lauren A Burt David A Hanley Emmanuel Biver Pawel Szulc Elisabeth Sornay-Rendu Blandine Merle Roland Chapurlat Eric Lespessailles Andy Kin On Wong David Goltzman Sundeep Khosla Serge Ferrari Mary L Bouxsein Douglas P Kiel Steven K Boyd 《Journal of bone and mineral research》2022,37(3):428-439
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