全文获取类型
收费全文 | 993721篇 |
免费 | 63916篇 |
国内免费 | 2327篇 |
专业分类
耳鼻咽喉 | 13208篇 |
儿科学 | 32040篇 |
妇产科学 | 27503篇 |
基础医学 | 138405篇 |
口腔科学 | 25227篇 |
临床医学 | 80513篇 |
内科学 | 202308篇 |
皮肤病学 | 19435篇 |
神经病学 | 80816篇 |
特种医学 | 40624篇 |
外国民族医学 | 336篇 |
外科学 | 158435篇 |
综合类 | 19833篇 |
一般理论 | 247篇 |
预防医学 | 73219篇 |
眼科学 | 21041篇 |
药学 | 68952篇 |
中国医学 | 1803篇 |
肿瘤学 | 56019篇 |
出版年
2018年 | 20070篇 |
2017年 | 16085篇 |
2016年 | 18264篇 |
2015年 | 9088篇 |
2014年 | 12653篇 |
2013年 | 19457篇 |
2012年 | 28660篇 |
2011年 | 37029篇 |
2010年 | 24378篇 |
2009年 | 21518篇 |
2008年 | 36333篇 |
2007年 | 40313篇 |
2006年 | 28137篇 |
2005年 | 29536篇 |
2004年 | 28826篇 |
2003年 | 29242篇 |
2002年 | 27562篇 |
2001年 | 41644篇 |
2000年 | 43048篇 |
1999年 | 36465篇 |
1998年 | 10148篇 |
1997年 | 9399篇 |
1996年 | 9231篇 |
1995年 | 8595篇 |
1994年 | 8253篇 |
1993年 | 7722篇 |
1992年 | 28317篇 |
1991年 | 27120篇 |
1990年 | 26538篇 |
1989年 | 25453篇 |
1988年 | 23653篇 |
1987年 | 23294篇 |
1986年 | 22345篇 |
1985年 | 21255篇 |
1984年 | 15872篇 |
1983年 | 13546篇 |
1982年 | 8173篇 |
1979年 | 14690篇 |
1978年 | 10271篇 |
1977年 | 8645篇 |
1976年 | 8214篇 |
1975年 | 8961篇 |
1974年 | 10730篇 |
1973年 | 10194篇 |
1972年 | 9661篇 |
1971年 | 8917篇 |
1970年 | 8609篇 |
1969年 | 8054篇 |
1968年 | 7703篇 |
1967年 | 7086篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Christopher D Hue Frances S Cho Siqi Cao Cameron R ”Dale” Bass David F Meaney Barclay Morrison III 《Journal of cerebral blood flow and metabolism》2015,35(7):1191-1198
Owing to the frequent incidence of blast-induced traumatic brain injury (bTBI) in recent military conflicts, there is an urgent need to develop effective therapies for bTBI-related pathologies. Blood-brain barrier (BBB) breakdown has been reported to occur after primary blast exposure, making restoration of BBB function and integrity a promising therapeutic target. We tested the hypothesis that treatment with dexamethasone (DEX) after primary blast injury potentiates recovery of an in vitro BBB model consisting of mouse brain endothelial cells (bEnd.3). DEX treatment resulted in complete recovery of transendothelial electrical resistance and hydraulic conductivity 1 day after injury, compared with 3 days for vehicle-treated injured cultures. Administration of RU486 (mifepristone) inhibited effects of DEX, confirming that barrier restoration was mediated by glucocorticoid receptor signaling. Potentiated recovery with DEX treatment was accompanied by stronger zonula occludens (ZO)-1 tight junction immunostaining and expression, suggesting that increased ZO-1 expression was a structural correlate to BBB recovery after blast. Interestingly, augmented ZO-1 protein expression was associated with specific upregulation of the α+ isoform but not the α− isoform. This is the first study to provide a mechanistic basis for potentiated functional recovery of an in vitro BBB model because of glucocorticoid treatment after primary blast injury. 相似文献
22.
M.T. Leccia N. Auffret F. Poli J.‐P. Claudel S. Corvec B. Dreno 《Journal of the European Academy of Dermatology and Venereology》2015,29(8):1485-1492
Acne vulgaris (acne) is a chronic inflammatory disease of the sebaceous gland, characterized by follicular hyperkeratinization, excessive colonization by Propionibacterium acnes (P. acnes) as well as immune reactions and inflammation. Despite an armamentarium of topical treatments available including benzoyl peroxide, retinoids and azelaic acid, topical antibiotics in monotherapies, especially erythromycin and clindamycin, are still used in Europe to treat acne. This intensive use led to antimicrobial‐resistant P. acnes and staphylococci strains becoming one of the main health issues worldwide. This is an update on the current topical acne treatments available in Europe, their mechanism of action, their potential to induce antimicrobial resistance and their clinical efficacy and safety. 相似文献
23.
24.
Wojciech Szychta M.D. Ph.D. Gheorghe Cerin M.D. Ph.D. F.E.S.C. Bogdan Adrian Popa M.D. Armienti Felice M.D. Guido Lanzillo M.D. Ph.D. Marco Diena M.D. Grzegorz Opolski M.D. Ph.D. F.E.S.C. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(6):1040-1043
Sinus venosus atrial septal defect (SV‐ASD) usually coexists with partial anomalous pulmonary vein connection (PAPVC). It is a difficult diagnosis in transthoracic echocardiography (TTE) due to eccentric position of defects. We present a rare case of atypical anatomical variation in PAPVC, which was never described before. Two right pulmonary veins drained into superior vena cava, which overrode SV‐ASD and interatrial septum, a third pulmonary vein into the right atrium. Complete diagnosis could not be set after TTE, nor transesophageal echocardiography, whereas angio‐CT was finally conclusive. This diagnostic approach allowed the surgical planning. 相似文献
25.
26.
27.
28.
O. Ieromina C. J. M. Musters P. M. Bodegom W. J. G. M. Peijnenburg M. G. Vijver 《Ecotoxicology (London, England)》2016,25(6):1170-1180
Analyzing functional species’ characteristics (species traits) that represent physiological, life history and morphological characteristics of species help understanding the impacts of various stressors on aquatic communities at field conditions. This research aimed to study the combined effects of pesticides and other environmental factors (temperature, dissolved oxygen, dissolved organic carbon, floating macrophytes cover, phosphate, nitrite, and nitrate) on the trait modality distribution of aquatic macrofauna communities. To this purpose, a field inventory was performed in a flower bulb growing area of the Netherlands with significant variation in pesticides pressures. Macrofauna community composition, water chemistry parameters and pesticide concentrations in ditches next to flower bulb fields were determined. Trait modalities of nine traits (feeding mode, respiration mode, locomotion type, resistance form, reproduction mode, life stage, voltinism, saprobity, maximum body size) likely to indicate pesticides impacts were analyzed. According to a redundancy analysis, phosphate -and not pesticides- constituted the main factor structuring the trait modality distribution of aquatic macrofauna. The functional composition could be ascribed for 2–4 % to pesticides, and for 3–11 % to phosphate. The lack of trait responses to pesticides may indicate that species may have used alternative strategies to adapt to ambient pesticides stress. Biomass of animals exhibiting trait modalities related to feeding by predation and grazing, presence of diapause form or dormancy, reproduction by free clutches and ovoviviparity, life stage of larvae and pupa, was negatively correlated to the concentration of phosphate. Hence, despite the high pesticide pollution in the area, variation in nutrient-related stressors seems to be the dominant driver of the functional composition of aquatic macrofauna assembly in agricultural ditches. 相似文献
29.
30.