全文获取类型
收费全文 | 152791篇 |
免费 | 10405篇 |
国内免费 | 770篇 |
专业分类
耳鼻咽喉 | 1406篇 |
儿科学 | 3898篇 |
妇产科学 | 2762篇 |
基础医学 | 20570篇 |
口腔科学 | 3455篇 |
临床医学 | 14724篇 |
内科学 | 32956篇 |
皮肤病学 | 2876篇 |
神经病学 | 14803篇 |
特种医学 | 6137篇 |
外国民族医学 | 6篇 |
外科学 | 23006篇 |
综合类 | 1904篇 |
现状与发展 | 2篇 |
一般理论 | 139篇 |
预防医学 | 11053篇 |
眼科学 | 3198篇 |
药学 | 10486篇 |
2篇 | |
中国医学 | 245篇 |
肿瘤学 | 10338篇 |
出版年
2023年 | 818篇 |
2022年 | 1238篇 |
2021年 | 2828篇 |
2020年 | 1956篇 |
2019年 | 2816篇 |
2018年 | 3428篇 |
2017年 | 2663篇 |
2016年 | 3046篇 |
2015年 | 3517篇 |
2014年 | 5033篇 |
2013年 | 6803篇 |
2012年 | 10520篇 |
2011年 | 11137篇 |
2010年 | 6349篇 |
2009年 | 6043篇 |
2008年 | 10197篇 |
2007年 | 10878篇 |
2006年 | 10348篇 |
2005年 | 10596篇 |
2004年 | 10001篇 |
2003年 | 9486篇 |
2002年 | 8907篇 |
2001年 | 1483篇 |
2000年 | 1120篇 |
1999年 | 1594篇 |
1998年 | 2106篇 |
1997年 | 1644篇 |
1996年 | 1421篇 |
1995年 | 1289篇 |
1994年 | 1140篇 |
1993年 | 1113篇 |
1992年 | 774篇 |
1991年 | 784篇 |
1990年 | 610篇 |
1989年 | 595篇 |
1988年 | 557篇 |
1987年 | 570篇 |
1986年 | 507篇 |
1985年 | 534篇 |
1984年 | 636篇 |
1983年 | 565篇 |
1982年 | 760篇 |
1981年 | 701篇 |
1980年 | 602篇 |
1979年 | 365篇 |
1978年 | 376篇 |
1977年 | 405篇 |
1976年 | 342篇 |
1975年 | 294篇 |
1974年 | 249篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Hanna Lee Mary K. Tan Andrew T. Yan Paul Angaran Paul Dorian Claudia Bucci Jean C. Gregoire Alan D. Bell Martin S. Green Peter L. Gross Allan Skanes Charles R. Kerr L. Brent Mitchell Jafna L. Cox Vidal Essebag Brett Heilbron Krishnan Ramanathan Carl Fournier Shaun G. Goodman 《The Canadian journal of cardiology》2019,35(2):160-168
Background
Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.Methods
We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).Results
Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.Conclusions
Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation. 相似文献42.
Thaís dos Santos Fontes Pereira Carolina Cavalieri Gomes Peter A Brennan Felipe Paiva Fonseca Ricardo Santiago Gomez 《Journal of oral pathology & medicine》2019,48(1):3-9
Fibrous dysplasia is a non‐neoplastic developmental process that affects the craniofacial bones, characterized by painless enlargement as a result of bone substitution by abnormal fibrous tissue. Postzygotic somatic activating mutations in the GNAS1 gene cause fibrous dysplasia and have been extensively investigated, as well as being helpful in the differential diagnosis of the disease. Fibrous dysplasia may involve one (monostotic) or multiple bones (polyostotic), sporadically or in association with McCune‐Albright syndrome, Jeffe‐Lichenstein syndrome, or Mazabreud syndrome. This review summarizes the current knowledge on fibrous dysplasia, emphasizing the value of integrating the understanding of its molecular pathogenesis with the clinical, radiological, and histopathological features. In addition, we address important aspects related to the differential diagnosis and patient management. 相似文献
43.
Auda A. Eltahla Fabio Luciani Peter A. White Andrew R. Lloyd Rowena A. Bull 《Viruses》2015,7(10):5206-5224
The hepatitis C virus (HCV) is a pandemic human pathogen posing a substantial health and economic burden in both developing and developed countries. Controlling the spread of HCV through behavioural prevention strategies has met with limited success and vaccine development remains slow. The development of antiviral therapeutic agents has also been challenging, primarily due to the lack of efficient cell culture and animal models for all HCV genotypes, as well as the large genetic diversity between HCV strains. On the other hand, the use of interferon-α-based treatments in combination with the guanosine analogue, ribavirin, achieved limited success, and widespread use of these therapies has been hampered by prevalent side effects. For more than a decade, the HCV RNA-dependent RNA polymerase (RdRp) has been targeted for antiviral development. Direct acting antivirals (DAA) have been identified which bind to one of at least six RdRp inhibitor-binding sites, and are now becoming a mainstay of highly effective and well tolerated antiviral treatment for HCV infection. Here we review the different classes of RdRp inhibitors and their mode of action against HCV. Furthermore, the mechanism of antiviral resistance to each class is described, including naturally occurring resistance-associated variants (RAVs) in different viral strains and genotypes. Finally, we review the impact of these RAVs on treatment outcomes with the newly developed regimens. 相似文献
44.
45.
Suzanne Maman Lusajo Kajula Peter Balvanz Mrema Kilonzo Marta Mulawa Thespina Yamanis 《Global public health》2016,11(10):1202-1215
Gender inequality is at the core of the HIV patterns that are evident in sub-Saharan Africa. Gender-based violence (GBV) and lack of economic opportunity are important structural determinants of HIV risk. We piloted a microfinance and health promotion intervention among social networks of primarily young men in Dar es Salaam. Twenty-two individuals participated in the microfinance component and 30 peer leaders were recruited and trained in the peer health leadership component. We collected and analysed observational data from trainings, monitoring data on loan repayment, and reports of peer conversations to assess the feasibility and acceptability of the intervention. Eighteen of the loan recipients (82%) paid back their loans, and of these 15 (83%) received a second, larger loan. Among the loan defaulters, one died, one had chronic health problems, and two disappeared, one of whom was imprisoned for theft. The majority of conversations reported by peer health leaders focused on condoms, sexual partner selection, and HIV testing. Few peer leaders reported conversations about GBV. We demonstrated the feasibility and acceptability of this innovative HIV and GBV prevention intervention. The lessons learned from this pilot have informed the implementation of a cluster-randomised trial of the microfinance and peer health leadership intervention. 相似文献
46.
47.
Peter Marhofer Malachy Columb Phil M. Hopkins Manfred Greher Daniela Marhofer Max R. Levi Bienzle Markus Zeitlinger 《British journal of anaesthesia》2019,122(4):525-531
Background
The efficacy of dexamethasone in extending the duration of local anaesthetic block is uncertain. In a randomised controlled triple blind crossover study in volunteers, we tested the hypothesis that neither i.v. nor perineurally administered dexamethasone prolongs the sensory block achieved with ropivacaine.Methods
Ultrasound-guided ulnar nerve blocks (ropivacaine 0.75% wt/vol, 3 ml, with saline 1 ml with or without dexamethasone 4 mg) were performed on three occasions in 24 male volunteers along with an i.v. injection of saline 1 ml with or without dexamethasone 4 mg. The combinations of saline and dexamethasone were as follows: control group, perineural and i.v. saline; perineural group, perineural dexamethasone and i.v. saline; i.v. group, perineural saline and i.v. dexamethasone. Sensory block was measured using a VAS in response to pinprick testing. The duration of sensory block was the primary outcome and time to onset of sensory block the secondary outcome.Results
All 24 subjects completed the trial. The median [inter-quartile range (IQR)] duration of sensory block was 6.87 (5.85–7.62) h in the control group, 7.37 (5.78–7.93) h in the perineural group and 7.37 (6.10–7.97) h in the i.v. group (P=0.61). There was also no significant difference in block onset time between the three groups.Conclusion
Dexamethasone 4 mg has no clinically relevant effect on the duration of sensory block provided by ropivacaine applied to the ulnar nerve.Clinical trial registration
DRKS, 00014604; EudraCT, 2018-001221-98. 相似文献48.
Marie Warrer Petersen Tine Sylvest Meyhoff Marie Helleberg Maj-Brit Nørregaard Kjær Anders Granholm Carl Johan Steensen Hjortsø Thomas Steen Jensen Morten Hylander Møller Peter Buhl Hjortrup Mik Wetterslev Gitte Kingo Vesterlund Lene Russell Vibeke Lind Jørgensen Klaus Tjelle Thomas Benfield Charlotte Suppli Ulrik Anne Sofie Andreasen Thomas Mohr Morten H. Bestle Lone Musaeus Poulsen Mette Friberg Hitz Thomas Hildebrandt Lene Surland Knudsen Anders Møller Christoffer Grant Sølling Anne Craveiro Brøchner Bodil Steen Rasmussen Henrik Nielsen Steffen Christensen Thomas Strøm Maria Cronhjort Rebecka Rubenson Wahlin Stephan Jakob Luca Cioccari Balasubramanian Venkatesh Naomi Hammond Vivekanand Jha Sheila Nainan Myatra Christian Gluud Theis Lange Anders Perner 《Acta anaesthesiologica Scandinavica》2020,64(9):1365-1375
Introduction
Severe acute respiratory syndrome coronavirus-2 has caused a pandemic of coronavirus disease (COVID-19) with many patients developing hypoxic respiratory failure. Corticosteroids reduce the time on mechanical ventilation, length of stay in the intensive care unit and potentially also mortality in similar patient populations. However, corticosteroids have undesirable effects, including longer time to viral clearance. Clinical equipoise on the use of corticosteroids for COVID-19 exists.Methods
The COVID STEROID trial is an international, randomised, stratified, blinded clinical trial. We will allocate 1000 adult patients with COVID-19 receiving ≥10 L/min of oxygen or on mechanical ventilation to intravenous hydrocortisone 200 mg daily vs placebo (0.9% saline) for 7 days. The primary outcome is days alive without life support (ie mechanical ventilation, circulatory support, and renal replacement therapy) at day 28. Secondary outcomes are serious adverse reactions at day 14; days alive without life support at day 90; days alive and out of hospital at day 90; all-cause mortality at day 28, day 90, and 1 year; and health-related quality of life at 1 year. We will conduct the statistical analyses according to this protocol, including interim analyses for every 250 patients followed for 28 days. The primary outcome will be compared using the Kryger Jensen and Lange test in the intention to treat population and reported as differences in means and medians with 95% confidence intervals.Discussion
The COVID STEROID trial will provide important evidence to guide the use of corticosteroids in COVID-19 and severe hypoxia.49.
50.