全文获取类型
收费全文 | 1638925篇 |
免费 | 113533篇 |
国内免费 | 2553篇 |
专业分类
耳鼻咽喉 | 22708篇 |
儿科学 | 53289篇 |
妇产科学 | 43165篇 |
基础医学 | 242774篇 |
口腔科学 | 46093篇 |
临床医学 | 147704篇 |
内科学 | 308592篇 |
皮肤病学 | 37435篇 |
神经病学 | 121582篇 |
特种医学 | 63249篇 |
外国民族医学 | 276篇 |
外科学 | 246497篇 |
综合类 | 33833篇 |
现状与发展 | 3篇 |
一般理论 | 404篇 |
预防医学 | 117733篇 |
眼科学 | 38254篇 |
药学 | 129230篇 |
10篇 | |
中国医学 | 4704篇 |
肿瘤学 | 97476篇 |
出版年
2019年 | 12229篇 |
2018年 | 17619篇 |
2017年 | 13779篇 |
2016年 | 15492篇 |
2015年 | 17277篇 |
2014年 | 23589篇 |
2013年 | 34928篇 |
2012年 | 47282篇 |
2011年 | 49916篇 |
2010年 | 29348篇 |
2009年 | 27634篇 |
2008年 | 46213篇 |
2007年 | 49584篇 |
2006年 | 50454篇 |
2005年 | 47624篇 |
2004年 | 45980篇 |
2003年 | 44054篇 |
2002年 | 42633篇 |
2001年 | 86424篇 |
2000年 | 88320篇 |
1999年 | 73423篇 |
1998年 | 18767篇 |
1997年 | 16319篇 |
1996年 | 16515篇 |
1995年 | 15627篇 |
1994年 | 14183篇 |
1993年 | 13361篇 |
1992年 | 55330篇 |
1991年 | 54050篇 |
1990年 | 52987篇 |
1989年 | 51409篇 |
1988年 | 46514篇 |
1987年 | 45268篇 |
1986年 | 42861篇 |
1985年 | 40211篇 |
1984年 | 29371篇 |
1983年 | 24846篇 |
1982年 | 13762篇 |
1979年 | 26563篇 |
1978年 | 18242篇 |
1977年 | 15951篇 |
1976年 | 14402篇 |
1975年 | 16281篇 |
1974年 | 18970篇 |
1973年 | 18289篇 |
1972年 | 17382篇 |
1971年 | 16272篇 |
1970年 | 15234篇 |
1969年 | 14443篇 |
1968年 | 12971篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Xiaoyan Lu Isabelle R. Miousse Sandra V. Pirela Jodene K. Moore Stepan Melnyk 《Nanotoxicology》2016,10(5):629-639
Evidence continues to grow on potential environmental health hazards associated with engineered nanomaterials (ENMs). While the geno- and cytotoxic effects of ENMs have been investigated, their potential to target the epigenome remains largely unknown. The aim of this study is two-fold: 1) determining whether or not industry relevant ENMs can affect the epigenome in vivo and 2) validating a recently developed in vitro epigenetic screening platform for inhaled ENMs. Laser printer-emitted engineered nanoparticles (PEPs) released from nano-enabled toners during consumer use and copper oxide (CuO) were chosen since these particles induced significant epigenetic changes in a recent in vitro companion study. In this study, the epigenetic alterations in lung tissue, alveolar macrophages and peripheral blood from intratracheally instilled mice were evaluated. The methylation of global DNA and transposable elements (TEs), the expression of the DNA methylation machinery and TEs, in addition to general toxicological effects in the lung were assessed. CuO exhibited higher cell-damaging potential to the lung, while PEPs showed a greater ability to target the epigenome. Alterations in the methylation status of global DNA and TEs, and expression of TEs and DNA machinery in mouse lung were observed after exposure to CuO and PEPs. Additionally, epigenetic changes were detected in the peripheral blood after PEPs exposure. Altogether, CuO and PEPs can induce epigenetic alterations in a mouse experimental model, which in turn confirms that the recently developed in vitro epigenetic platform using macrophage and epithelial cell lines can be successfully utilized in the epigenetic screening of ENMs. 相似文献
82.
83.
84.
85.
86.
A case of bullous pemphigoid associated with psoriasis vulgaris showing Hailey–Hailey disease‐like histopathological changes in regenerated epidermis without genomic mutation in ATP2C1 or ATP2A2 gene
下载免费PDF全文
![点击此处可从《Journal of the European Academy of Dermatology and Venereology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
87.
88.
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
89.
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
90.
Feasibility and Diagnostic Potential of Pulmonary Transit Time Measurement by Contrast Echocardiography: A Pilot Study
下载免费PDF全文
![点击此处可从《Echocardiography (Mount Kisco, N.Y.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)