全文获取类型
收费全文 | 12145篇 |
免费 | 710篇 |
国内免费 | 186篇 |
专业分类
耳鼻咽喉 | 198篇 |
儿科学 | 117篇 |
妇产科学 | 141篇 |
基础医学 | 2123篇 |
口腔科学 | 336篇 |
临床医学 | 1073篇 |
内科学 | 2069篇 |
皮肤病学 | 470篇 |
神经病学 | 1056篇 |
特种医学 | 868篇 |
外科学 | 1598篇 |
综合类 | 63篇 |
一般理论 | 2篇 |
预防医学 | 487篇 |
眼科学 | 286篇 |
药学 | 1265篇 |
中国医学 | 153篇 |
肿瘤学 | 736篇 |
出版年
2024年 | 7篇 |
2023年 | 78篇 |
2022年 | 296篇 |
2021年 | 484篇 |
2020年 | 203篇 |
2019年 | 307篇 |
2018年 | 370篇 |
2017年 | 279篇 |
2016年 | 390篇 |
2015年 | 514篇 |
2014年 | 662篇 |
2013年 | 752篇 |
2012年 | 1052篇 |
2011年 | 986篇 |
2010年 | 641篇 |
2009年 | 546篇 |
2008年 | 751篇 |
2007年 | 773篇 |
2006年 | 647篇 |
2005年 | 568篇 |
2004年 | 456篇 |
2003年 | 391篇 |
2002年 | 319篇 |
2001年 | 226篇 |
2000年 | 193篇 |
1999年 | 140篇 |
1998年 | 110篇 |
1997年 | 80篇 |
1996年 | 90篇 |
1995年 | 71篇 |
1994年 | 60篇 |
1993年 | 66篇 |
1992年 | 42篇 |
1991年 | 41篇 |
1990年 | 49篇 |
1989年 | 49篇 |
1988年 | 49篇 |
1987年 | 50篇 |
1986年 | 33篇 |
1985年 | 37篇 |
1984年 | 26篇 |
1983年 | 13篇 |
1982年 | 16篇 |
1981年 | 26篇 |
1980年 | 20篇 |
1979年 | 13篇 |
1978年 | 14篇 |
1977年 | 20篇 |
1976年 | 12篇 |
1975年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
151.
Remondino A Kwon SH Communal C Pimentel DR Sawyer DB Singh K Colucci WS 《Circulation research》2003,92(2):136-138
Stimulation of beta-adrenergic receptors (betaARs) causes apoptosis in adult rat ventricular myocytes (ARVMs). The role of reactive oxygen species (ROS) in mediating betaAR-stimulated apoptosis is not known. Stimulation of betaARs with norepinephrine (10 micromol/L) in the presence of prazosin (100 nmol/L) for 24 hours increased the number of apoptotic myocytes as determined by TUNEL staining by 3.6- fold. The superoxide dismutase/catalase mimetics Mn(III)tetrakis(1-methyl-4-pyridyl)porphyrin pentachloride (MnTMPyP; 10 micromol/L) and Euk-134 decreased betaAR-stimulated apoptosis by 89+/-6% and 76+/-10%, respectively. Infection with an adenovirus expressing catalase decreased betaAR-stimulated apoptosis by 82+/-15%. The mitochondrial permeability transition pore inhibitor bongkrekic acid (50 micromol/L) decreased betaAR-stimulated apoptosis by 76+/-8%, and the caspase inhibitor zVAD-fmk (25 micromol/L) decreased betaAR-stimulated apoptosis by 62+/-11%. betaAR-stimulated cytochrome c release was inhibited by MnTMPyP. betaAR stimulation caused c-Jun NH2-terminal kinase (JNK) activation, which was abolished by MnTMPyP. Transfection with an adenovirus expressing dominant-negative JNK inhibited betaAR-stimulated apoptosis by 81+/-12%, and the JNK inhibitor SP600125 inhibited both betaAR-stimulated apoptosis and cytochrome c release. Thus, betaAR-stimulated apoptosis in ARVMs involves ROS/JNK-dependent activation of the mitochondrial death pathway. 相似文献
152.
153.
Bouguila J Limam F Le Bourgeois M Kwon T Biebuyck N Marchac V De Blic J Scheinmann P 《Revue de pneumologie clinique》2003,59(4):209-212
A 22-month-old infant developed purulent pleurisy caused by Streptococcus pneumoniae and a hemolytic uremic syndrome. The diagnosis was suggested by the classical triad: hemolytic anemia, renal failure and thrombocytemia confirmed by renal biopsy which demonstrated extensive cortical necrosis. Renal involvement was severe, justifying an indication for renal transplantation. 相似文献
154.
155.
156.
Dongsun Park Yun-Hui Yang Dae Kwon Bae Sun Hee Lee Goeun Yang Jangbeen Kyung Dajeong Kim Ehn-Kyoung Choi Seong Won Lee Gon Hyung Kim Jin Tae Hong Kyung-Chul Choi Hong Jun Lee Seung U. Kim Yun-Bae Kim 《Neurobiology of aging》2013
Aging is characterized by progressive loss of cognitive and memory functions as well as decrease in physical activities. In the present study, a human neural stem cell line (F3 NSC) over-expressing choline acetyltransferase (F3.ChAT), an enzyme responsible for acetylcholine synthesis, was generated and transplanted in the brain of 18-month-old male ICR mice. Four weeks post-transplantation, neurobehavioral functions, expression of ChAT enzyme, production of acetylcholine and neurotrophic factors, and expression of cholinergic nervous system markers in transplanted animals were investigated. F3.ChAT NSCs markedly improved both the cognitive function and physical activity of aging animals, in parallel with the elevation of brain acetylcholine level. Transplanted F3 and F3.ChAT cells were found to differentiate into neurons and astrocytes, and to produce ChAT proteins. Transplantation of the stem cells increased brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), enhanced expression of Trk B, and restored host microtubule-associated protein 2 and cholinergic nervous system. The results demonstrate that human NSCs over-expressing ChAT improve cognitive function and physical activity of aging mice, not only by producing ACh directly but also by restoring cholinergic neuronal integrity, which might be mediated by neurotrophins BDNF and NGF. 相似文献
157.
Purpose
Other than a single case report, no diffusion tensor tractography (DTT) studies of the precommissural fornix in the human brain have been conducted. In the current study, we attempted to visualize the precommissural fornix in the human brain using DTT.Materials and Methods
We recruited 36 healthy volunteers for this study. Diffusion tensor images were scanned using a 1.5-T scanner, and the precommissural fornix was analyzed using Functional Magnetic Resonance Imaging of the Brain (FMRIB) software. Values of fractional anisotropy (FA), mean diffusivity (MD), and tract volume of the precommissural fornix were measured.Results
The precommissural fornix originated from the hippocampal formation on each hemisphere as a crus; both crura were then joined to the body of the fornix. The body of the fornix continued anteriorly to the level just superior to the anterior commissure, where it divided into each column of the precommissural fornix. Each column descended anteriorly to the anterior commissure and terminated in the septal nuclei. Values of FA, MD, and tract volumes of the precommissural fornix did not differ between the right and left hemispheres (p>0.05).Conclusion
We believe that the methodology and results of this study would be helpful to future research on the precommissural fornix and in the elucidation of the pathology of diseases involving the precommissural fornix. 相似文献158.
Young-Guk Ko Byoung-Kwon Lee Woong Chol Kang Jae-Youn Moon Yun Hyeong Cho Seong Hun Choi Myeong-Ki Hong Yangsoo Jang Jong-Youn Kim Pil-Ki Min Hyuck-Moon Kwon PRINCIPLE Investigators 《Yonsei medical journal》2013,54(4):957-964
Purpose
To investigate the effect of pretreatment with intravenous nicorandil on the incidence of contrast-induced nephropathy (CIN) in patients with renal dysfunction undergoing coronary angiography.Materials and Methods
This randomized controlled multicenter study enrolled a total of 166 patients (nicorandil n=81; control n=85) with an estimated glomerular filtration rate <60 mL/min. Nicorandil 12 mg dissolved in 100 mL of 0.9% saline was administered intravenously for 30 minutes just prior to coronary angiography in the nicorandil group. The same volume of only saline was given to the control group. The primary end-point was the incidence of CIN, defined as >0.5 mg/dL increase or >25% rise in serum creatinine (SCr) concentration within 48 hours of contrast exposure compared to baseline.Results
The final analysis included 149 patients (nicorandil n=73; control n=76). The baseline characteristics and the total volume of the used contrast (Iodixanol, 125.6±69.1 mL vs. 126.9±74.6 mL, p=0.916) were similar between the two groups. The incidence of CIN also did not differ between the nicorandil and control groups (6.8% vs. 6.6%, p=0.794). There was no difference between the two groups in the relative change in SCr from baseline to peak level within 48 hours after coronary angiography (-1.58±24.07% vs. 0.96±17.49%, p=0.464), although the nicorandil group showed less absolute change in SCr than the control group (-0.01±0.43 mg/mL vs. 0.02±0.31 mg/mL, p=0.005).Conclusion
Prophylactic intravenous infusion of nicorandil did not decrease the incidence of CIN in patients with renal dysfunction undergoing coronary angiography. 相似文献159.
160.