全文获取类型
收费全文 | 3258953篇 |
免费 | 225401篇 |
国内免费 | 8440篇 |
专业分类
耳鼻咽喉 | 44809篇 |
儿科学 | 107925篇 |
妇产科学 | 90280篇 |
基础医学 | 458322篇 |
口腔科学 | 89593篇 |
临床医学 | 296241篇 |
内科学 | 633505篇 |
皮肤病学 | 78031篇 |
神经病学 | 263621篇 |
特种医学 | 125664篇 |
外国民族医学 | 918篇 |
外科学 | 485992篇 |
综合类 | 65444篇 |
现状与发展 | 6篇 |
一般理论 | 1175篇 |
预防医学 | 246007篇 |
眼科学 | 73744篇 |
药学 | 243401篇 |
13篇 | |
中国医学 | 7089篇 |
肿瘤学 | 181014篇 |
出版年
2019年 | 25497篇 |
2018年 | 36035篇 |
2017年 | 27891篇 |
2016年 | 32224篇 |
2015年 | 36161篇 |
2014年 | 49638篇 |
2013年 | 74244篇 |
2012年 | 99049篇 |
2011年 | 104718篇 |
2010年 | 63005篇 |
2009年 | 60175篇 |
2008年 | 97600篇 |
2007年 | 103840篇 |
2006年 | 105704篇 |
2005年 | 101322篇 |
2004年 | 97355篇 |
2003年 | 93915篇 |
2002年 | 90684篇 |
2001年 | 159347篇 |
2000年 | 163401篇 |
1999年 | 137516篇 |
1998年 | 38864篇 |
1997年 | 34494篇 |
1996年 | 34689篇 |
1995年 | 33512篇 |
1994年 | 30535篇 |
1993年 | 28642篇 |
1992年 | 106378篇 |
1991年 | 102417篇 |
1990年 | 99591篇 |
1989年 | 96347篇 |
1988年 | 88010篇 |
1987年 | 85998篇 |
1986年 | 80894篇 |
1985年 | 76972篇 |
1984年 | 57115篇 |
1983年 | 48134篇 |
1982年 | 28292篇 |
1981年 | 25074篇 |
1979年 | 50564篇 |
1978年 | 35263篇 |
1977年 | 30597篇 |
1976年 | 27779篇 |
1975年 | 30124篇 |
1974年 | 35366篇 |
1973年 | 33748篇 |
1972年 | 31863篇 |
1971年 | 29628篇 |
1970年 | 27242篇 |
1969年 | 26231篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
Assessment of Myocardial Infarct Size by Three‐Dimensional and Two‐Dimensional Speckle Tracking Echocardiography: A Comparative Study to Single Photon Emission Computed Tomography 下载免费PDF全文
52.
53.
T. Wu L. G. Trahair M. J. Bound C. F. Deacon M. Horowitz C. K. Rayner K. L. Jones 《Diabetic medicine》2015,32(5):595-600
54.
Context Withania somnifera (L.) Dunal is traditionally used for treating various ailments, but lacks scientific evaluation.Objective This study evaluates Withania somnifera (WS) for its effect on platelet activity and inflammatory enzymes.Materials and methods Aqueous and ethanolic (1:1) leaf extracts were subjected to in vitro indirect haemolytic activity using Naja naja venom, human platelet aggregation was quantified for lipid peroxidation using arachidonic acid (AA) as agonist and 5-lipoxygenase (5-LOX) levels were determined using standard spectrometric assays. Further, molecular docking was performed by the ligand fit method using molegro software package (Molegro ApS, Aarhus, Denmark).Results The study found that aqueous and ethanol extracts have very negligible effect (15%) with an IC50 value of 13.8?mg/mL on PLA2 from Naja naja venom. Further, extracts of WS also had very little effect (18%) with an IC50 value of 16.6?mg/mL on malondialdehyde (MDA) formation. However, a 65% inhibition of 5-LOX with an IC50 value of 0.92?mg/mL was observed in 1:1 ethanol extracts. The same was evident from SAR model with the active ingredient withaferin A binding predominantly on Phe 77, Tyr 98, Arg 99, Asp 164, Leu 168, Ser 382, Arg 395, Tyr 396 and Tyr 614 with an atomic contact energy value of??128.96 compared to standard phenidone (?103.61). Thus, the current study validates the application of WS for inflammatory diseases.Conclusion This study reveals the inhibitory potential of W. somnifera on inflammatory enzymes and platelet aggregation. Thus, WS can serve as a newer, safer and affordable medicine for inflammatory diseases. 相似文献
55.
56.
Feasibility and Diagnostic Potential of Pulmonary Transit Time Measurement by Contrast Echocardiography: A Pilot Study 下载免费PDF全文
57.
Harit Kapoor Kush Raj Lohani Tommy H. Lee Devendra K. Agrawal Sumeet K. Mittal 《CTS Clinical and Translational Science》2015,8(6):841-847
Esophageal adenocarcinoma is the fastest rising cancer in the United States. It develops from long‐standing gastroesophageal reflux disease which affects >20% of the general population. It carries a very poor prognosis with 5‐year survival <20%. The disease is known to sequentially progress from reflux esophagitis to a metaplastic precursor, Barrett''s esophagus and then onto dysplasia and esophageal adenocarcinoma. However, only few patients with reflux develop Barrett''s esophagus and only a minority of these turn malignant. The reason for this heterogeneity in clinical progression is unknown. To improve patient management, molecular changes which facilitate disease progression must be identified. Animal models can provide a comprehensive functional and anatomic platform for such a study. Rats and mice have been the most widely studied but disease homology with humans has been questioned. No animal model naturally simulates the inflammation to adenocarcinoma progression as in humans, with all models requiring surgical bypass or destruction of existing antireflux mechanisms. Valuable properties of individual models could be utilized to holistically evaluate disease progression. In this review paper, we critically examined the current animal models of Barrett''s esophagus, their differences and homologies with human disease and how they have shaped our current understanding of Barrett''s carcinogenesis. 相似文献
58.
59.
60.