全文获取类型
收费全文 | 1530篇 |
免费 | 203篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 22篇 |
儿科学 | 54篇 |
妇产科学 | 24篇 |
基础医学 | 109篇 |
口腔科学 | 39篇 |
临床医学 | 229篇 |
内科学 | 309篇 |
皮肤病学 | 114篇 |
神经病学 | 62篇 |
特种医学 | 151篇 |
外科学 | 304篇 |
综合类 | 94篇 |
现状与发展 | 30篇 |
预防医学 | 58篇 |
眼科学 | 21篇 |
药学 | 48篇 |
中国医学 | 3篇 |
肿瘤学 | 80篇 |
出版年
2024年 | 19篇 |
2023年 | 180篇 |
2022年 | 17篇 |
2021年 | 27篇 |
2020年 | 61篇 |
2019年 | 32篇 |
2018年 | 68篇 |
2017年 | 58篇 |
2016年 | 42篇 |
2015年 | 60篇 |
2014年 | 89篇 |
2013年 | 82篇 |
2012年 | 44篇 |
2011年 | 56篇 |
2010年 | 85篇 |
2009年 | 99篇 |
2008年 | 46篇 |
2007年 | 62篇 |
2006年 | 36篇 |
2005年 | 39篇 |
2004年 | 33篇 |
2003年 | 26篇 |
2002年 | 26篇 |
2001年 | 15篇 |
2000年 | 19篇 |
1999年 | 29篇 |
1998年 | 35篇 |
1997年 | 49篇 |
1996年 | 40篇 |
1995年 | 35篇 |
1994年 | 29篇 |
1993年 | 34篇 |
1992年 | 8篇 |
1991年 | 8篇 |
1990年 | 11篇 |
1989年 | 25篇 |
1988年 | 20篇 |
1987年 | 15篇 |
1986年 | 4篇 |
1985年 | 11篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1982年 | 8篇 |
1981年 | 10篇 |
1980年 | 12篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1976年 | 13篇 |
1975年 | 10篇 |
1974年 | 3篇 |
排序方式: 共有1751条查询结果,搜索用时 15 毫秒
41.
42.
43.
44.
45.
The evaluation of gastrointestinal function in diabetic patients 总被引:2,自引:0,他引:2
Quigley EM 《World journal of gastroenterology : WJG》1999,5(4):13-282
Nowadays,anumberofoptionsareavailablefortheasesmentofgastricmotorfunction.Thus,aglobalevaluationofgastricmotorfunctionmaybeob... 相似文献
46.
Toxicity of thallium on isolated rat liver mitochondria: The role of oxidative stress and MPT pore opening 下载免费PDF全文
M R Eskandari Vida Mashayekhi Majid Aslani Mir‐Jamal Hosseini 《Environmental toxicology》2015,30(2):232-241
Thallium(I) is a highly toxic heavy metal; however, up to now, its mechanisms are poorly understood. The authors' previous studies showed that this compound could induce reactive oxygen species (ROS) formation, reduced glutathione (GSH) oxidation, membrane lipid peroxidation, and mitochondrial membrane potential (MMP) collapse in isolated rat hepatocyte. Because the liver is the storage site of thallium, it seems that the liver mitochondria are one of the important targets for hepatotoxicity. In this investigation, the effects of thallium on mitochondria were studied to investigate its mechanisms of toxicity. Mitochondria were isolated from rat liver and incubated with different concentrations of thallium (25–200 µM). Thallium(I)‐treated mitochondria showed a marked elevation in oxidative stress parameters accompanied by MMP collapse when compared with the control group. These results showed that different concentrations of thallium (25–200 µM) induced a significant (P < 0.05) increase in mitochondrial ROS formation, ATP depletion, GSH oxidation, mitochondrial outer membrane rupture, mitochondrial swelling, MMP collapse, and cytochrome c release. In general, these data strongly supported that the thallium(I)‐induced liver toxicity is a result of the disruptive effect of this metal on the mitochondrial respiratory complexes (I, II, and IV), which are the obvious causes of metal‐induced ROS formation and ATP depletion. The latter two events, in turn, trigger cell death signaling via opening of mitochondrial permeability transition pore and cytochrome c expulsion. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 232–241, 2015. 相似文献
47.
48.
Effects of Enteral Nutrition on the Barrier Function of the Intestinal Mucosa and Dopamine Receptor Expression in Rats With Traumatic Brain Injury 下载免费PDF全文
Background: Impaired intestinal mucosal barrier (IMB) function is common in traumatic brain injury (TBI), but dopamine receptors (DRs) change in intestinal mucosa after TBI, and effects of enteral nutrition (EN) and supplements on IMB function remain unclear. Our purpose was to study the effects of EN and supplements on intestinal mucosal permeability (IMPB) and the expression of DRs DRD1 and DRD2 in the intestinal mucosa of rats with TBI. Methods: Forty‐eight rats were divided into 8 groups; control, animals with TBI, dopamine group, animals with TBI treated with dopamine antagonist, EN alone, or EN combined with glutamine, probiotics, or a combination of probiotics and glutamine daily after TBI. Results: The IMPB was improved in the glutamine, probiotics, and combination groups. Including probiotics improved IMPB more than adding glutamine, and bacterial translocation in the intestines after TBI was reduced in the probiotics and combination groups (all Ps < .01). TBI led to elevated DRD1 and DRD2 mRNA and protein levels, which were reduced in the DA antagonist, glutamine, probiotics, and combination groups. DRD2 mRNA and protein levels in the probiotics and combination groups were decreased more than in the DA antagonist group (all Ps < .01). The increased IMPB after TBI correlated with increased DRD1 and DRD2 levels in the rat intestinal mucosa. Conclusion: EN supplemented with probiotics or combining glutamine and probiotics lowers the increased IMPB, bacterial translocation, and DRD1 and DRD2 mRNA and protein expression in rat intestinal mucosa caused by TBI. 相似文献
49.
GCH1 attenuates cardiac autonomic nervous remodeling in canines with atrial‐tachypacing via tetrahydrobiopterin pathway regulated by microRNA‐206 下载免费PDF全文
50.
Kibaek Lee Junjun Zhu Judy Shum Yongjie Zhang Satish C. Muluk Ankur Chandra Mark K. Eskandari Ender A. Finol 《Annals of biomedical engineering》2013,41(3):562-576
An abdominal aortic aneurysm (AAA) carries one of the highest mortality rates among vascular diseases when it ruptures. To predict the role of surface curvature in rupture risk assessment, a discriminatory analysis of aneurysm geometry characterization was conducted. Data was obtained from 205 patient-specific computed tomography image sets corresponding to three AAA population subgroups: patients under surveillance, those that underwent elective repair of the aneurysm, and those with an emergent repair. Each AAA was reconstructed and their surface curvatures estimated using the biquintic Hermite finite element method. Local surface curvatures were processed into ten global curvature indices. Statistical analysis of the data revealed that the L2-norm of the Gaussian and Mean surface curvatures can be utilized as classifiers of the three AAA population subgroups. The application of statistical machine learning on the curvature features yielded 85.5% accuracy in classifying electively and emergent repaired AAAs, compared to a 68.9% accuracy obtained by using maximum aneurysm diameter alone. Such combination of non-invasive geometric quantification and statistical machine learning methods can be used in a clinical setting to assess the risk of rupture of aneurysms during regular patient follow-ups. 相似文献