全文获取类型
收费全文 | 1301篇 |
免费 | 59篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 44篇 |
妇产科学 | 8篇 |
基础医学 | 77篇 |
口腔科学 | 28篇 |
临床医学 | 87篇 |
内科学 | 342篇 |
皮肤病学 | 44篇 |
神经病学 | 109篇 |
特种医学 | 36篇 |
外科学 | 242篇 |
综合类 | 8篇 |
一般理论 | 2篇 |
预防医学 | 32篇 |
眼科学 | 145篇 |
药学 | 75篇 |
中国医学 | 1篇 |
肿瘤学 | 76篇 |
出版年
2024年 | 1篇 |
2023年 | 18篇 |
2022年 | 35篇 |
2021年 | 95篇 |
2020年 | 43篇 |
2019年 | 57篇 |
2018年 | 70篇 |
2017年 | 31篇 |
2016年 | 36篇 |
2015年 | 41篇 |
2014年 | 58篇 |
2013年 | 74篇 |
2012年 | 104篇 |
2011年 | 130篇 |
2010年 | 85篇 |
2009年 | 48篇 |
2008年 | 92篇 |
2007年 | 82篇 |
2006年 | 68篇 |
2005年 | 58篇 |
2004年 | 36篇 |
2003年 | 24篇 |
2002年 | 23篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 5篇 |
1998年 | 4篇 |
1997年 | 1篇 |
1996年 | 4篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1992年 | 5篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 3篇 |
1979年 | 1篇 |
1974年 | 1篇 |
1970年 | 2篇 |
1969年 | 1篇 |
排序方式: 共有1365条查询结果,搜索用时 0 毫秒
31.
32.
Park D O'Doherty I Somvanshi RK Bethke A Schroeder FC Kumar U Riddle DL 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(25):9917-9922
A chemically diverse family of small-molecule signals, the ascarosides, control developmental diapause (dauer), olfactory learning, and social behaviors of the nematode model organism, Caenorhabditis elegans. The ascarosides act upstream of conserved signaling pathways, including the insulin, TGF-β, serotonin, and guanylyl cyclase pathways; however, the sensory processes underlying ascaroside function are poorly understood. Because ascarosides often are multifunctional and show strongly synergistic effects, characterization of their receptors will be essential for understanding ascaroside biology and may provide insight into molecular mechanisms that produce synergistic outcomes in small-molecule sensing. Based on DAF-8 immunoprecipitation, we here identify two G-protein-coupled receptors, DAF-37 and DAF-38, which cooperatively mediate ascaroside perception. daf-37 mutants are defective in all responses to ascr#2, one of the most potent dauer-inducing ascarosides, although this mutant responds normally to other ascarosides. In contrast, daf-38 mutants are partially defective in responses to several different ascarosides. Through cell-specific overexpression, we show that DAF-37 regulates dauer when expressed in ASI neurons and adult behavior when expressed in ASK neurons. Using a photoaffinity-labeled ascr#2 probe and amplified luminescence assays (AlphaScreen), we demonstrate that ascr#2 binds to DAF-37. Photobleaching fluorescent energy transfer assays revealed that DAF-37 and DAF-38 form heterodimers, and we show that heterodimerization strongly increases cAMP inhibition in response to ascr#2. These results suggest that that the ascarosides' intricate signaling properties result in part from the interaction of highly structure-specific G-protein-coupled receptors such as DAF-37 with more promiscuous G-protein-coupled receptors such as DAF-38. 相似文献
33.
34.
The endothelial progenitor cell (EPC) capture stent is an innovative device that makes use of the ability of bone marrow-derived EPCs to migrate to injured arterial segments to facilitate healing. The EPC antibody surface, consisting of a covalently coupled polysaccharide intermediate coating with anti-human CD34 antibodies, is attached to a stainless steel stent. Upon stent placement, the anti-human CD34 antibodies will attract circulating EPCs, which are expected to develop into mature functional endothelium. This accelerated healing strategy aims to lower the risk of restenosis and stent thrombosis, as well as obviate prolonged dual antiplatelet therapy. Since the first-in-man study in 2003, a number of small-to-medium size registry and postmarketing studies that confirmed the good safety profile of the EPC capture stent have been published. However, due to lack of large-scale randomized trials, its effectiveness, compared with bare metal stents and drug-eluting stents, cannot be ascertained. Based on restudy angiographic data, instent late loss was approximately 0.7-0.9 mm, which compares unfavorably with that of drug-eluting stents. In order to improve the effectiveness of the EPC capture stent in reducing restenosis-while maintaining its pro-healing property-a bioengineered sirolimus-eluting stent known as the Combo stent was recently designed to combine the EPC capture technology with the abluminal elution of sirolimus. Data from animal studies have been encouraging. The first-in-man study of the Combo stent has been completed and results were presented. (J Interven Cardiol 2012;25:493-500). 相似文献
35.
36.
37.
Desai R Hall AJ Lopman BA Shimshoni Y Rennick M Efron N Matias Y Patel MM Parashar UD 《Clinical infectious diseases》2012,55(8):e75-e78
Google Internet query share (IQS) data for gastroenteritis-related search terms correlated strongly with contemporaneous national (R(2)?=?0.70) and regional (R(2)?=?0.74) norovirus surveillance data in the United States. IQS data may facilitate rapid identification of norovirus season onset, elevated peak activity, and potential emergence of novel strains. 相似文献
38.
Desai R Lopman BA Shimshoni Y Harris JP Patel MM Parashar UD 《Clinical infectious diseases》2012,54(9):e115-e118
Google-based Internet query share (IQS) for rotavirus search terms correlated well with US rotavirus laboratory detections from 2004 to 2010 (r = 0.88; P < .001), capturing the reduction observed during postvaccine years (2008-2010). IQS analysis could become an inexpensive and reliable supplement for monitoring the impact of rotavirus vaccination in the United States. 相似文献
39.
40.