全文获取类型
收费全文 | 3947篇 |
免费 | 244篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 22篇 |
儿科学 | 130篇 |
妇产科学 | 38篇 |
基础医学 | 480篇 |
口腔科学 | 46篇 |
临床医学 | 379篇 |
内科学 | 1055篇 |
皮肤病学 | 58篇 |
神经病学 | 440篇 |
特种医学 | 171篇 |
外科学 | 582篇 |
综合类 | 11篇 |
预防医学 | 258篇 |
眼科学 | 87篇 |
药学 | 213篇 |
中国医学 | 1篇 |
肿瘤学 | 235篇 |
出版年
2024年 | 3篇 |
2023年 | 31篇 |
2022年 | 42篇 |
2021年 | 135篇 |
2020年 | 88篇 |
2019年 | 118篇 |
2018年 | 128篇 |
2017年 | 111篇 |
2016年 | 105篇 |
2015年 | 111篇 |
2014年 | 150篇 |
2013年 | 233篇 |
2012年 | 365篇 |
2011年 | 358篇 |
2010年 | 184篇 |
2009年 | 187篇 |
2008年 | 256篇 |
2007年 | 271篇 |
2006年 | 278篇 |
2005年 | 241篇 |
2004年 | 216篇 |
2003年 | 191篇 |
2002年 | 153篇 |
2001年 | 26篇 |
2000年 | 26篇 |
1999年 | 25篇 |
1998年 | 21篇 |
1997年 | 26篇 |
1996年 | 17篇 |
1995年 | 21篇 |
1994年 | 13篇 |
1993年 | 14篇 |
1992年 | 7篇 |
1991年 | 7篇 |
1990年 | 6篇 |
1989年 | 5篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 5篇 |
1985年 | 3篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1964年 | 1篇 |
1961年 | 1篇 |
排序方式: 共有4206条查询结果,搜索用时 15 毫秒
91.
92.
Reduced tonicity stimulates an inflammatory response in nucleus pulposus tissue that can be limited by a COX‐2‐specific inhibitor 下载免费PDF全文
Bart van Dijk Esther Potier Maarten van DIjk Marloes Langelaan Nicole Papen‐Botterhuis Keita Ito 《Journal of orthopaedic research》2015,33(11):1724-1731
In intervertebral disc herniation with nucleus pulposus (NP) extrusion, the elicited inflammatory response is considered a key pain mechanism. However, inflammatory cytokines are reported in extruded herniated tissue, even before monocyte infiltration, suggesting that the tissue itself initiates the inflammation. Since herniated tissue swells, we investigated whether this simple mechanobiological stimulus alone could provoke an inflammatory response that could cause pain. Furthermore, we investigated whether sustained‐release cyclooxygenase‐2 (COX2) inhibitor would be beneficial in such conditions. Healthy bovine NP explants were allowed to swell freely or confined. The swelling explants were treated with Celecoxib, applied either as a bolus or in sustained‐release. Swelling explants produced elevated levels of interleukin‐6 (IL‐6) and prostaglandin E2 (PGE2) for 28 days, while confined explants did not. Both a high concentration bolus and 10 times lower concentration in sustained release completely inhibited PGE2 production, but did not affect IL‐6 production. Swelling of NP tissue, without the inflammatory system response, can trigger cytokine production and Celecoxib, even in bolus form, may be useful for pain control in extruded disc herniation. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1724–1731, 2015. 相似文献
93.
Biagini E Elhendy A Bax JJ Rizzello V Schinkel AF van Domburg RT Kertai MD Krenning BJ Bountioukos M Rapezzi C Branzi A Simoons ML Poldermans D 《Journal of the American College of Cardiology》2005,45(1):93-97
OBJECTIVES: The aim of this study was to investigate the effects of gender on long-term prognosis of patients undergoing dobutamine stress echocardiography (DSE). BACKGROUND: Gender differences in the predictors of outcome among patients with known or suspected coronary artery disease undergoing DSE have not been adequately studied. METHODS: We studied 2,276 men and 1,105 women with known or suspected coronary artery disease who underwent DSE. Follow-up events were cardiac death and nonfatal myocardial infarction (MI). RESULTS: Dobutamine stress echocardiography was normal in 687 men (30%) and 483 women (44%) (p <0.0001). Ischemia on DSE was present in 1,194 men (52%) and 416 women (38%) (p <0.001). During a mean follow-up of 7 +/- 3.4 years, there were 894 (26%) deaths (442 attributed to cardiac causes) and 145 (4%) nonfatal MIs. The annual cardiac event rate was 2.5% in men and 1.2% in women with normal DSE. Independent predictors of cardiac events in patients with normal DSE using a Cox proportional hazards regression analysis were male gender (hazard ratio [HR]: 1.7 [range 1.1 to 2.8]), age (HR: 1.02 [range 1.01 to 1.04]), history of heart failure (HR: 3.4 [range 1.5 to 7.9]), previous MI (HR: 1.7 [range 1.1 to 2.8]), and diabetes (HR: 2.4 [range 1.3 to 4.5]). Independent predictors of cardiac events in patients with an abnormal DSE were age (HR: 1.03 [range 1.02 to 1.04]), history of heart failure (HR: 1.7 [range 1.3 to 2.1]), diabetes (HR: 1.4 [range 1.1 to 1.8]), heart rate at rest (HR: 2.8 [range 1.4 to 5.8]), wall motion abnormalities at rest (HR: 1.06 [range 1.04 to 1.09]), and ischemia on DSE (HR: 1.04 [range 1.02 to 1.07]). Myocardial ischemia was an independent predictor of cardiac events in both men and women. CONCLUSIONS: Dobutamine stress echocardiography provides independent prognostic information in both men and women. In patients with normal DSE, gender is independently associated with cardiac events. The outcome of patients with abnormal DSE is not related to gender, after adjusting for stress echocardiographic abnormalities. 相似文献
94.
95.
Charlene A Wong Maarten Sap Andrew Schwartz Robert Town Tom Baker Lyle Ungar Raina M Merchant 《Journal of medical Internet research》2015,17(2)
Background
Traditional metrics of the impact of the Affordable Care Act (ACA) and health insurance marketplaces in the United States include public opinion polls and marketplace enrollment, which are published with a lag of weeks to months. In this rapidly changing environment, a real-time barometer of public opinion with a mechanism to identify emerging issues would be valuable.Objective
We sought to evaluate Twitter’s role as a real-time barometer of public sentiment on the ACA and to determine if Twitter sentiment (the positivity or negativity of tweets) could be predictive of state-level marketplace enrollment.Methods
We retrospectively collected 977,303 ACA-related tweets in March 2014 and then tested a correlation of Twitter sentiment with marketplace enrollment by state.Results
A 0.10 increase in the sentiment score was associated with an 8.7% increase in enrollment at the state level (95% CI 1.32-16.13; P=.02), a correlation that remained significant when adjusting for state Medicaid expansion (P=.02) or use of a state-based marketplace (P=.03).Conclusions
This correlation indicates Twitter’s potential as a real-time monitoring strategy for future marketplace enrollment periods; marketplaces could systematically track Twitter sentiment to more rapidly identify enrollment changes and potentially emerging issues. As a repository of free and accessible consumer-generated opinions, this study reveals a novel role for Twitter in the health policy landscape. 相似文献96.
Ayano Kelly Kathleen Tymms Maarten de Wit Susan J. Bartlett Marita Cross Therese Dawson Mary De Vera Vicki Evans Michael Gill Geraldine Hassett Irwin Lim Karine Manera Gabor Major Lyn March Sean ONeill Marieke Scholte-Voshaar Premarani Sinnathurai Daniel Sumpton Armando Teixeira‐Pinto Peter Tugwell Bart van den Bemt Allison Tong 《Arthritis care & research》2020,72(10):1410-1419
97.
98.
High resolution SNP array profiling identifies variability in retinoblastoma genome stability 下载免费PDF全文
Berber M. Mol Maarten P. G. Massink Annemarie H. van der Hout Charlotte J. Dommering Johannes M. A. Zaman Machteld I. Bosscha Wijnanda A. Kors Hanne E. Meijers‐Heijboer Gertjan J. L. Kaspers Hein te Riele Annette C. Moll Jacqueline Cloos Josephine C. Dorsman 《Genes, chromosomes & cancer》2014,53(1):1-14
Both hereditary and nonhereditary retinoblastoma (Rb) are commonly initiated by loss of both copies of the retinoblastoma tumor suppressor gene (RB1), while additional genomic changes are required for tumor initiation and progression. Our aim was to determine whether there is genomic heterogeneity between different clinical Rb subtypes. Therefore, 21 Rb tumors from 11 hereditary patients and 10 nonhereditary Rb patients were analyzed using high‐resolution single nucleotide polymorphism (SNP) arrays and gene losses and gains were validated with Multiplex Ligation‐dependent Probe Amplification. In these tumors only a few focal aberrations were detected. The most frequent was a focal gain on chromosome 2p24.3, the minimal region of gain encompassing the oncogene MYCN. The genes BAZ1A, OTX2, FUT8, and AKT1 were detected in four focal regions on chromosome 14 in one nonhereditary Rb. There was a large difference in number of copy number aberrations between tumors. A subset of nonhereditary Rbs turned out to be the most genomic unstable, while especially very young patients with hereditary Rb display stable genomes. Established Rb copy number aberrations, including gain of chromosome arm 1q and loss of chromosome arm 16q, turned out to be preferentially associated with the nonhereditary Rbs with later age of diagnosis. In contrast, copy number neutral loss of heterozygosity was detected mainly on chromosome 13, where RB1 resides, irrespective of hereditary status or age. Focal amplifications and deletions and copy number neutral loss of heterozygosity besides chromosome 13 appear to be rare events in retinoblastoma. © 2013 Wiley Periodicals, Inc. 相似文献
99.
Healthcare professionals and managers in hospitals are frequently suggested to learn from industry and business to improve quality and efficiency. However, evidence that the implementation of industrial techniques and business methods has a meaningful effect on patient outcomes is often lacking. An explanation for this phenomenon is thought to be the complexity of the hospital organisation and the diversity of patients. In this article, we use the practice approach to discuss the application of industrial techniques and business methods in healthcare. We employ a practice model that offers three perspectives to understand professional practices: Identity and intrinsic values, Interests of stakeholders, and Ideals and basic beliefs (Triple I). This model demonstrates that the nature of healthcare practices differs strongly from the nature of industrial and business practices. Healthcare has a moral nature that does not let itself be easily organised along technological or business categories. This may provide a fundamental explanation of why industrial techniques and business methods in general will be less successful in healthcare. At the same time, this model invites hospitals to develop innovative approaches that do justice to the identity and intrinsic values of healthcare. In this process, insights from industry and business cannot be copied but have to be used as sources of inspiration. 相似文献
100.
Abraham H. Hulst MD Maarten J. Visscher MD Marc B. Godfried PhD Bram Thiel Bastiaan M. Gerritse PhD Thierry V. Scohy PhD R. Arthur Bouwman PhD Mark G. A. Willemsen MD Markus W. Hollmann PhD Benedikt Preckel PhD J. Hans DeVries PhD Jeroen Hermanides PhD 《Diabetes, obesity & metabolism》2020,22(4):557-565