全文获取类型
收费全文 | 1168188篇 |
免费 | 78095篇 |
国内免费 | 1494篇 |
专业分类
耳鼻咽喉 | 16479篇 |
儿科学 | 38853篇 |
妇产科学 | 31850篇 |
基础医学 | 166398篇 |
口腔科学 | 32125篇 |
临床医学 | 101824篇 |
内科学 | 221504篇 |
皮肤病学 | 27089篇 |
神经病学 | 88639篇 |
特种医学 | 46977篇 |
外国民族医学 | 232篇 |
外科学 | 178953篇 |
综合类 | 22994篇 |
现状与发展 | 1篇 |
一般理论 | 289篇 |
预防医学 | 79566篇 |
眼科学 | 27273篇 |
药学 | 92555篇 |
7篇 | |
中国医学 | 3055篇 |
肿瘤学 | 71114篇 |
出版年
2018年 | 12012篇 |
2017年 | 9539篇 |
2016年 | 10954篇 |
2015年 | 12263篇 |
2014年 | 16599篇 |
2013年 | 24243篇 |
2012年 | 33166篇 |
2011年 | 34920篇 |
2010年 | 20605篇 |
2009年 | 19419篇 |
2008年 | 32609篇 |
2007年 | 34990篇 |
2006年 | 35710篇 |
2005年 | 34139篇 |
2004年 | 32770篇 |
2003年 | 31428篇 |
2002年 | 30362篇 |
2001年 | 65291篇 |
2000年 | 66729篇 |
1999年 | 55351篇 |
1998年 | 13709篇 |
1997年 | 12225篇 |
1996年 | 12086篇 |
1995年 | 11289篇 |
1994年 | 10250篇 |
1993年 | 9750篇 |
1992年 | 40804篇 |
1991年 | 39139篇 |
1990年 | 38584篇 |
1989年 | 36990篇 |
1988年 | 33268篇 |
1987年 | 32394篇 |
1986年 | 30534篇 |
1985年 | 28642篇 |
1984年 | 20797篇 |
1983年 | 17447篇 |
1982年 | 9610篇 |
1981年 | 8425篇 |
1979年 | 18541篇 |
1978年 | 12535篇 |
1977年 | 11171篇 |
1976年 | 9641篇 |
1975年 | 11073篇 |
1974年 | 12696篇 |
1973年 | 12291篇 |
1972年 | 11632篇 |
1971年 | 10915篇 |
1970年 | 9990篇 |
1969年 | 9636篇 |
1968年 | 8568篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
M. D. Wiles A. El-Nayal G. Elton M. Malaj J. Winterbottom C. Gillies I. K. Moppett K. Bauchmuller 《Anaesthesia》2022,77(2):143-152
Pulse oximetry is used widely to titrate oxygen therapy and for triage in patients who are critically ill. However, there are concerns regarding the accuracy of pulse oximetry in patients with COVID-19 pneumonitis and in patients who have a greater degree of skin pigmentation. We aimed to determine the impact of patient ethnicity on the accuracy of peripheral pulse oximetry in patients who were critically ill with COVID-19 pneumonitis by conducting a retrospective observational study comparing paired measurements of arterial oxygen saturation measured by co-oximetry on arterial blood gas analysis (SaO2) and the corresponding peripheral oxygenation saturation measured by pulse oximetry (SpO2). Bias was calculated as the mean difference between SaO2 and SpO2 measurements and limits of agreement were calculated as bias ±1.96 SD. Data from 194 patients (135 White ethnic origin, 34 Asian ethnic origin, 19 Black ethnic origin and 6 other ethnic origin) were analysed consisting of 6216 paired SaO2 and SpO2 measurements. Bias (limits of agreement) between SaO2 and SpO2 measurements was 0.05% (−2.21–2.30). Patient ethnicity did not alter this to a clinically significant degree: 0.28% (1.79–2.35), −0.33% (−2.47–2.35) and −0.75% (−3.47–1.97) for patients of White, Asian and Black ethnic origin, respectively. In patients with COVID-19 pneumonitis, SpO2 measurements showed a level of agreement with SaO2 values that was in line with previous work, and this was not affected by patient ethnicity. 相似文献
112.
113.
114.
115.
Jenny U. Johansson Nathaniel S. Woodling Qian Wang Maharshi Panchal Xibin Liang Angel Trueba-Saiz Holden D. Brown Siddhita D. Mhatre Taylor Loui Katrin I. Andreasson 《The Journal of clinical investigation》2015,125(1):350-364
Microglia, the innate immune cells of the CNS, perform critical inflammatory and noninflammatory functions that maintain normal neural function. For example, microglia clear misfolded proteins, elaborate trophic factors, and regulate and terminate toxic inflammation. In Alzheimer’s disease (AD), however, beneficial microglial functions become impaired, accelerating synaptic and neuronal loss. Better understanding of the molecular mechanisms that contribute to microglial dysfunction is an important objective for identifying potential strategies to delay progression to AD. The inflammatory cyclooxygenase/prostaglandin E2 (COX/PGE2) pathway has been implicated in preclinical AD development, both in human epidemiology studies and in transgenic rodent models of AD. Here, we evaluated murine models that recapitulate microglial responses to Aβ peptides and determined that microglia-specific deletion of the gene encoding the PGE2 receptor EP2 restores microglial chemotaxis and Aβ clearance, suppresses toxic inflammation, increases cytoprotective insulin-like growth factor 1 (IGF1) signaling, and prevents synaptic injury and memory deficits. Our findings indicate that EP2 signaling suppresses beneficial microglia functions that falter during AD development and suggest that inhibition of the COX/PGE2/EP2 immune pathway has potential as a strategy to restore healthy microglial function and prevent progression to AD. 相似文献
116.
Walid K. Abu Saleh Phillip Mason Odeaa Al Jabbari Hany Samir Brian A. Bruckner 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(6):569-571
The Impella 5.0, a percutaneously inserted left ventricular assist device, has been used to support patients who have severe heart failure or who are undergoing high-risk percutaneous coronary intervention. We report our surgical placement of the Impella 5.0, through a graft sewn to the aorta, to unload the left ventricle of a 59-year-old man who was undergoing venoarterial extracorporeal membrane oxygenation for postcardiotomy shock. The patient underwent successful placement of a long-term left ventricular assist device before his discharge from the hospital. The versatility of the Impella 5.0 is exemplified in this patient who was successfully bridged to long-term support. 相似文献
117.
Increased arterial stiffness in young normotensive patients with Turner syndrome: associations with vascular biomarkers
下载免费PDF全文
![点击此处可从《Clinical endocrinology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
118.
More than just crushing: a prospective pre‐post intervention study to reduce drug preparation errors in patients with feeding tubes
下载免费PDF全文
![点击此处可从《Journal of clinical pharmacy and therapeutics》网站下载免费的PDF全文](/ch/ext_images/free.gif)
119.
120.
Clinical Spectrum of Capillary Malformation–Arteriovenous Malformation Syndrome Presenting to a Pediatric Dermatology Practice: A Retrospective Study
下载免费PDF全文
![点击此处可从《Pediatric dermatology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Nicole A. Weitz M.D. Christine T. Lauren M.D. Gerald G. Behr M.D. June K. Wu M.D. Jessica J. Kandel M.D. Philip M. Meyers M.D. Sally Sultan M.D. Kwame Anyane‐Yeboa M.D. Kimberly D. Morel M.D. Maria C. Garzon M.D. 《Pediatric dermatology》2015,32(1):76-84
Capillary malformation–arteriovenous malformation syndrome (CM‐AVM) is an autosomal dominant disorder caused by RASA1 mutations. The prevalence and phenotypic spectrum are unknown. Evaluation of patients with multiple CMs is challenging because associated AVMs can be life threatening. The objective of this study was to describe the clinical characteristics of children presenting with features of CM‐AVM to an academic pediatric dermatology practice. After institutional review board approval was received, a retrospective chart review was performed of patients presenting between 2009 and 2012 with features of CM‐AVM. We report nine cases. Presenting symptoms ranged from extensive vascular stains and cardiac failure to CMs noted incidentally during routine skin examination. All demonstrated multiple CMs, two had Parkes Weber syndrome, and two had multiple infantile hemangiomas. Seven patients had family histories of multiple CMs; three had family histories of large, atypical CMs. Six had personal or family histories of AVMs. Genetic evaluation was recommended for all and was pursued by six families; four RASA1 mutations were identified, including one de novo. Consultations with neurology, cardiology, and orthopedics were recommended. Most patients (89%) have not required treatment to date. CM‐AVM is an underrecognized condition with a wide clinical spectrum that often presents in childhood. Further evaluation may be indicated in patients with multiple CMs. This study is limited by its small and retrospective nature. 相似文献