全文获取类型
收费全文 | 2412篇 |
免费 | 165篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 35篇 |
儿科学 | 82篇 |
妇产科学 | 74篇 |
基础医学 | 383篇 |
口腔科学 | 53篇 |
临床医学 | 211篇 |
内科学 | 475篇 |
皮肤病学 | 106篇 |
神经病学 | 292篇 |
特种医学 | 100篇 |
外国民族医学 | 1篇 |
外科学 | 204篇 |
综合类 | 8篇 |
预防医学 | 148篇 |
眼科学 | 32篇 |
药学 | 159篇 |
中国医学 | 8篇 |
肿瘤学 | 220篇 |
出版年
2023年 | 24篇 |
2022年 | 46篇 |
2021年 | 93篇 |
2020年 | 68篇 |
2019年 | 75篇 |
2018年 | 87篇 |
2017年 | 77篇 |
2016年 | 96篇 |
2015年 | 90篇 |
2014年 | 115篇 |
2013年 | 137篇 |
2012年 | 209篇 |
2011年 | 211篇 |
2010年 | 121篇 |
2009年 | 105篇 |
2008年 | 162篇 |
2007年 | 128篇 |
2006年 | 124篇 |
2005年 | 121篇 |
2004年 | 93篇 |
2003年 | 87篇 |
2002年 | 64篇 |
2001年 | 9篇 |
2000年 | 15篇 |
1999年 | 19篇 |
1998年 | 12篇 |
1997年 | 13篇 |
1996年 | 13篇 |
1995年 | 9篇 |
1994年 | 6篇 |
1993年 | 7篇 |
1992年 | 14篇 |
1991年 | 7篇 |
1990年 | 13篇 |
1989年 | 11篇 |
1988年 | 8篇 |
1987年 | 8篇 |
1986年 | 8篇 |
1985年 | 6篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1981年 | 5篇 |
1980年 | 6篇 |
1978年 | 5篇 |
1977年 | 6篇 |
1976年 | 6篇 |
1974年 | 7篇 |
1973年 | 4篇 |
1971年 | 6篇 |
1968年 | 6篇 |
排序方式: 共有2591条查询结果,搜索用时 451 毫秒
111.
Verena Theiler-Schwetz Christian Trummer Martin R. Grübler Martin H. Keppel Armin Zittermann Andreas Tomaschitz Spyridon N. Karras Winfried Mrz Stefan Pilz Stephanie Gngler 《Nutrients》2022,14(7)
Accumulating evidence suggests that potential cardiovascular benefits of vitamin D supplementation may be restricted to individuals with very low 25-hydroxyvitamin D (25(OH)D) concentrations; the effect of vitamin D on blood pressure (BP) remains unclear. We addressed this issue in a post hoc analysis of the double-blind, randomized, placebo-controlled Styrian Vitamin D Hypertension Trial (2011–2014) with 200 hypertensive patients with 25(OH)D levels <30 ng/mL. We evaluated whether 2800 IU of vitamin D3/day or placebo (1:1) for 8 weeks affects 24-hour systolic ambulatory BP in patients with 25(OH)D concentrations <20 ng/mL, <16 ng/mL, and <12 ng/mL and whether achieved 25(OH)D concentrations were associated with BP measures. Taking into account correction for multiple testing, p values < 0.0026 were considered significant. No significant treatment effects on 24-hour BP were observed when different baseline 25(OH)D thresholds were used (all p-values > 0.30). However, there was a marginally significant trend towards an inverse association between the achieved 25(OH)D level with 24-hour systolic BP (−0.196 per ng/mL 25(OH)D, 95% CI (−0.325 to −0.067); p = 0.003). In conclusion, we could not document the antihypertensive effects of vitamin D in vitamin D-deficient individuals, but the association between achieved 25(OH)D concentrations and BP warrants further investigations on cardiovascular benefits of vitamin D in severe vitamin D deficiency. 相似文献
112.
113.
Keser Tobias Kofler Mario Katzmayr Mariella Schiefecker Alois J. Rass Verena Ianosi Bogdan A. Lindner Anna Gaasch Maxime Beer Ronny Rhomberg Paul Schmutzhard Erich Pfausler Bettina Helbok Raimund 《Neurocritical care》2020,33(1):132-139
Neurocritical Care - Despite the tremendous impact of swallowing disorders on outcome following ischemic stroke, little is known about the incidence of dysphagia after subarachnoid hemorrhage (SAH)... 相似文献
114.
115.
Ronny Redlich Ilona Schneider Nicole Kerkenberg Nils Opel Jonas Bauhaus Verena Enneking Jonathan Repple Elisabeth J. Leehr Dominik Grotegerd Claas Khler Katharina Frster Katharina Dohm Susanne Meinert Tim Hahn Harald Kugel Kathrin Schwarte Christiane Schettler Katharina Domschke Volker Arolt Walter Heindel Bernhard T. Baune Weiqi Zhang Christa Hohoff Udo Dannlowski 《Human brain mapping》2020,41(3):594-604
Epigenetic alterations of the brain‐derived neurotrophic factor (BDNF) gene have been associated with psychiatric disorders in humans and with differences in amygdala BDNF mRNA levels in rodents. This human study aimed to investigate the relationship between the functional BDNF‐Val66Met polymorphism, its surrounding DNA methylation in BDNF exon IX, amygdala reactivity to emotional faces, and personality traits. Healthy controls (HC, n = 189) underwent functional MRI during an emotional face‐matching task. Harm avoidance, novelty seeking and reward dependence were measured using the Tridimensional Personality Questionnaire (TPQ). Individual BDNF methylation profiles were ascertained and associated with several BDNF single nucleotide polymorphisms surrounding the BDNF‐Val66Met, amygdala reactivity, novelty seeking and harm avoidance. Higher BDNF methylation was associated with higher amygdala reactivity (x = 34, y = 0, z = ?26, t(166) = 3.00, TFCE = 42.39, p(FWE) = .045), whereby the BDNF‐Val66Met genotype per se did not show any significant association with brain function. Furthermore, novelty seeking was negatively associated with BDNF methylation (r = ?.19, p = .015) and amygdala reactivity (r = ?.17, p = .028), while harm avoidance showed a trend for a positive association with BDNF methylation (r = .14, p = .066). The study provides first insights into the relationship among BDNF methylation, BDNF genotype, amygdala reactivity and personality traits in humans, highlighting the multidimensional relations among genetics, epigenetics, and neuronal functions. The present study suggests a possible involvement of epigenetic BDNF modifications in psychiatric disorders and related brain functions, whereby high BDNF methylation might reduce BDNF mRNA expression and upregulate amygdala reactivity. 相似文献
116.
117.
118.
Johannes Hofer Andreas R. Janecke L.B. Zimmerhackl Magdalena Riedl Alejandra Rosales Thomas Giner Gerard Cortina Carola J. Haindl Barbara Petzelberger Miriam Pawlik Verena Jeller Udo Vester Bettina Gadner Michael van Husen Michael L. Moritz Reinhard Würzner Therese Jungraithmayr for the German-Austrian HUS Study Group 《Clinical journal of the American Society of Nephrology》2013,8(3):407-415
119.
120.