全文获取类型
收费全文 | 400358篇 |
免费 | 28549篇 |
国内免费 | 2297篇 |
专业分类
耳鼻咽喉 | 4949篇 |
儿科学 | 9364篇 |
妇产科学 | 8238篇 |
基础医学 | 55315篇 |
口腔科学 | 7795篇 |
临床医学 | 39340篇 |
内科学 | 81051篇 |
皮肤病学 | 7588篇 |
神经病学 | 35458篇 |
特种医学 | 16086篇 |
外国民族医学 | 11篇 |
外科学 | 59039篇 |
综合类 | 5487篇 |
现状与发展 | 5篇 |
一般理论 | 395篇 |
预防医学 | 29974篇 |
眼科学 | 10552篇 |
药学 | 30050篇 |
4篇 | |
中国医学 | 1935篇 |
肿瘤学 | 28568篇 |
出版年
2023年 | 1919篇 |
2022年 | 1507篇 |
2021年 | 9740篇 |
2020年 | 5595篇 |
2019年 | 8691篇 |
2018年 | 10173篇 |
2017年 | 7562篇 |
2016年 | 8960篇 |
2015年 | 11268篇 |
2014年 | 15220篇 |
2013年 | 19846篇 |
2012年 | 30063篇 |
2011年 | 30596篇 |
2010年 | 17499篇 |
2009年 | 15237篇 |
2008年 | 25411篇 |
2007年 | 26110篇 |
2006年 | 25227篇 |
2005年 | 24798篇 |
2004年 | 22882篇 |
2003年 | 20857篇 |
2002年 | 19124篇 |
2001年 | 6437篇 |
2000年 | 5603篇 |
1999年 | 5548篇 |
1998年 | 4323篇 |
1997年 | 3454篇 |
1996年 | 2596篇 |
1995年 | 2863篇 |
1994年 | 2423篇 |
1993年 | 2130篇 |
1992年 | 2774篇 |
1991年 | 2700篇 |
1990年 | 2317篇 |
1989年 | 2179篇 |
1988年 | 2076篇 |
1987年 | 1951篇 |
1986年 | 1921篇 |
1985年 | 1822篇 |
1984年 | 1824篇 |
1983年 | 1647篇 |
1982年 | 1701篇 |
1981年 | 1653篇 |
1980年 | 1447篇 |
1979年 | 1200篇 |
1978年 | 1132篇 |
1977年 | 999篇 |
1976年 | 904篇 |
1975年 | 753篇 |
1974年 | 822篇 |
排序方式: 共有10000条查询结果,搜索用时 670 毫秒
31.
32.
33.
34.
35.
36.
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
37.
38.
39.
40.
James Milligan Joseph Lee Matt Smith Lindsay Donaldson Peter Athanasopoulos Kent Bassett-Spiers 《The journal of spinal cord medicine》2020,43(2):223-233
Context: Persons with spinal cord injury (SCI) experience significant challenges when they access primary care and community services.Design: A provincial summit was held to direct research, education, and innovation for primary and community care for SCI.Setting: Toronto, Ontario, Canada.Participants: Key stakeholders (N?=?95) including persons with SCI and caregivers, clinicians from primary care, rehabilitation, and specialized care, researchers, advocacy groups, and policy makers.Methods: A one-day facilitated meeting that included guest speakers, panel discussions and small group discussions was held to generate potential solutions to current issues related to SCI care and to foster collaborative relationships to advance care for SCI. Perspectives on SCI management were shared by primary care, neurosurgery, rehabilitation, and members of the SCI communityOutcome Measures: Discussions were focused on five domains: knowledge translation and dissemination, application of best practices, communication, research, and patient service accessibility.Results: Summit participants identified issues and prioritized solutions to improve primary and community care including the creation of a network of key stakeholders to enable knowledge creation and dissemination; an online repository of SCI resources, integrated health records, and a clinical network for SCI care; development and implementation of strategies to improve care transitions across sectors; implementation of effective care models and improved access to services; and utilization of empowerment frameworks to support self-management.Conclusions: This summit identified priorities for further collaborative efforts to advance SCI primary and community care and will inform the development of a provincial SCI strategy aimed at improving the system of care for SCI. 相似文献