全文获取类型
收费全文 | 123922篇 |
免费 | 12853篇 |
国内免费 | 3962篇 |
专业分类
耳鼻咽喉 | 825篇 |
儿科学 | 2050篇 |
妇产科学 | 1441篇 |
基础医学 | 23356篇 |
口腔科学 | 3110篇 |
临床医学 | 7556篇 |
内科学 | 18568篇 |
皮肤病学 | 2304篇 |
神经病学 | 12493篇 |
特种医学 | 3348篇 |
外国民族医学 | 29篇 |
外科学 | 10392篇 |
综合类 | 12710篇 |
现状与发展 | 15篇 |
预防医学 | 5343篇 |
眼科学 | 1262篇 |
药学 | 19378篇 |
36篇 | |
中国医学 | 4643篇 |
肿瘤学 | 11878篇 |
出版年
2024年 | 287篇 |
2023年 | 2105篇 |
2022年 | 4984篇 |
2021年 | 5706篇 |
2020年 | 4764篇 |
2019年 | 5287篇 |
2018年 | 5021篇 |
2017年 | 4857篇 |
2016年 | 4495篇 |
2015年 | 5195篇 |
2014年 | 7557篇 |
2013年 | 7822篇 |
2012年 | 6811篇 |
2011年 | 8115篇 |
2010年 | 6505篇 |
2009年 | 6542篇 |
2008年 | 6420篇 |
2007年 | 5521篇 |
2006年 | 4770篇 |
2005年 | 4474篇 |
2004年 | 3794篇 |
2003年 | 3326篇 |
2002年 | 2447篇 |
2001年 | 2097篇 |
2000年 | 1761篇 |
1999年 | 1637篇 |
1998年 | 1559篇 |
1997年 | 1514篇 |
1996年 | 1373篇 |
1995年 | 1279篇 |
1994年 | 1143篇 |
1993年 | 1078篇 |
1992年 | 840篇 |
1991年 | 762篇 |
1990年 | 651篇 |
1989年 | 550篇 |
1988年 | 523篇 |
1987年 | 520篇 |
1986年 | 618篇 |
1985年 | 902篇 |
1984年 | 915篇 |
1983年 | 670篇 |
1982年 | 688篇 |
1981年 | 618篇 |
1980年 | 526篇 |
1979年 | 445篇 |
1978年 | 284篇 |
1977年 | 236篇 |
1976年 | 239篇 |
1975年 | 156篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
《The Journal of thoracic and cardiovascular surgery》2023,165(2):449-459.e4
ObjectiveThe objective of this study was to investigate the association between morphological variation and postsurgical pulmonary vein (PV) stenosis (PPVS) in patients with cardiac total anomalous pulmonary venous connection (TAPVC).MethodsThis single-center, retrospective study included 168 pediatric patients who underwent surgical repair of cardiac TAPVC from 2013 to 2019 (connection to the coronary sinus [CS], n = 136; connection directly to the right atrium [RA], n = 32). Three-dimensional computed tomography modeling and geometric analysis were performed to investigate the morphological features; their relevance to the PPVS was examined.ResultsThe connection type had no association with PPVS (CS type: 18% vs right atrial type: 19%; P = .89) but there was a higher incidence of PPVS in patients with a single PV orifice than > 1 orifice (P < .001). Confluence-to-total PV area ratio (hazard ratio, 4.78, 95% CI, 1.86-12.32; P = .001) and length of drainage route (hazard ratio, 1.22; 95% CI, 1.14-1.31; P < .001) had a 4- and 1-fold increase in the risk for PPVS in the CS type after adjustment for age and preoperative pulmonary venous obstruction. In the right atrial type, those with anomalous PV return to the RA roof were more likely to develop PPVS than to the posterior wall of the RA (P < .001).ConclusionsThe number of inter-junction PV orifice correlated with PPVS development in cardiac TAPVC. The confluence-to-total PV ratio, length of drainage route, and anomalous PV return to the RA roof are important predictors for PPVS. Morphological subcategorization in this clinical setting can potentially assist in surgical decision-making. 相似文献
53.
54.
ObjectiveThe purpose of this paper is to review the efficacy and safety profile in children treated with topical 0.03% Tacrolimus ointment for vernal keratoconjunctivitis in Middle East and to propose a treatment posology. According to recent studies, a complex non-IgE dependent mechanism plays a relevant role in the pathogenesis of vernal keratoconjunctivitis. Numerous cells and mediators have been found in the serum, conjunctiva and tears of patients with Vernal keratoconjunctivitis.DesignThis case series included 10 patients from a single centre, pediatric department of a tertiary hospital with active symptomatic vernal keratoconjunctivitis. All the patients had proliferative lesions and corneal involvement despite conventional medications, including topical steroids. All other medications, systemic and topical: steroids, antihistamines and cyclosporine, were unsuccessful. Patients were treated with topical 0.03% Tacrolimus ointment twice daily for 8 weeks and then once a day for the next two month followed by thrice a week for two months. The changes in symptoms and signs after treatment were evaluated, also the development of possible complications was assessed.ResultsThe results showed a significant reduction in signs and symptoms after 4 weeks of the treatment. Clinical resolution of giant papillae and corneal lesions were seen within eight weeks and no additional drug was required during that period, except tear substitutes. Treatment was continued for period of two months and then slowly reduced.ConclusionThe use of 0.03% Tacrolimus ointment is safe and effective in children refractory to conventional treatment of vernal keratoconjunctivitis even in high temperature climate as Middle East. Due to the effectiveness of the treatment, the dosage used may be proposed for conventional use. 相似文献
55.
56.
《Health Policy and Technology》2022,11(3):100647
BackgroundUnequal housing access resulted in more than 150 million homeless people worldwide, with millions more expected to be added every year due to the ongoing climate-related crises. Homeless population has a counterproductive effect on the social, psychological integration efforts by the community and exposure to other severe health-related issues. Geographic Information Systems (GIS) have long been applied in urban planning and policy, housing and homelessness, and health-related research.MethodsWe used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method to systematically review 24 articles collected from multiple databases (n = 10) that focused on health-related issues among homeless people and used geospatial analysis techniques in their research.ResultsOur findings indicated a geographic clustering of case study locations– 26 out of the 31 case study sites are from the USA and Canada. Studies used spatial analysis techniques to identify hotspots, clusters and patterns of patient location and population distribution. Studies also reported relationships among the location of homeless shelters and substance use, discarded needles, different infectious and non-infectious disease clusters.ConclusionMost studies were restricted in analyzing and visualizing the patterns and disease clusters; however, geospatial analyses techniques are useful and offer diverse techniques for a more sophisticated understanding of the spatial characteristics of the health issues among homeless people. Better integration of GIS in health research among the homeless would help formulate sensible policies to counter health inequities among this vulnerable population group. 相似文献
57.
58.
59.
Yuan Peng Yuman Li Haiyan Cao Liu Hong Yu Wang Mingxing Xie 《Journal of ultrasound in medicine》2019,38(2):539-544
A pulmonary artery (PA) sling is a very rare congenital cardiovascular anomaly, and only a few studies have reported PA slings in fetuses. The relationship of the PA, aorta, ductus arteriosus, and trachea can be evaluated in the 3‐vessel and 3‐vessel and trachea views during fetal echocardiography. A PA sling can be detected by abnormal positioning of the left PA in relation to the trachea when sweeping from the 3‐vessel view cranially to the 3‐vessel and trachea view. Here we report 3 cases of fetal PA slings and their follow‐ups. Two cases were confirmed by postnatal echocardiography, and the other case was confirmed by a cardiovascular cast after pregnancy termination. We emphasize that the 3‐vessel and 3‐vessel and trachea views are of crucial importance in the prenatal diagnosis of a PA sling. 相似文献
60.
K. Miura S. Yamaoka K. Arizono S. Ohba T. Koga T. Kawasaki N. Yoshida I. Asahina 《The British journal of oral & maxillofacial surgery》2019,57(6):529-535
Our aim was to evaluate the long-term skeletal stability of the mandible in 21 patients after orthognathic surgery with physiological positioning. The measurement points SNB, B point (X, Y), Pog (X, Y), and the angle of the ramus were measured on cephalometric photographs to assess skeletal stability preoperatively, immediately after operation, and one and two years postoperatively. In addition, we evaluated the clinical symptoms of disorders of the temporomandibular joint (TMJ). The analysis of the cephalometric photographs showed that SNB, B point X, and Pog X showed no significant differences among the postoperative time points. On the other hand, B point Y and Pog Y showed no significant differences throughout the study period. We compared the angle of the ramus before operation and two years postoperatively, and no significant difference was found. In addition, no cases showed any pathological symptoms of disorders of the TMJ two years postoperatively. The long-term stability after orthognathic surgery with physiological positioning was confirmed, and it seems to be a reliable orthognathic treatment in patients with mandibular prognathism. 相似文献