全文获取类型
收费全文 | 4667篇 |
免费 | 187篇 |
国内免费 | 36篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 93篇 |
妇产科学 | 112篇 |
基础医学 | 526篇 |
口腔科学 | 73篇 |
临床医学 | 446篇 |
内科学 | 1176篇 |
皮肤病学 | 126篇 |
神经病学 | 453篇 |
特种医学 | 217篇 |
外科学 | 627篇 |
综合类 | 8篇 |
一般理论 | 2篇 |
预防医学 | 197篇 |
眼科学 | 33篇 |
药学 | 415篇 |
中国医学 | 13篇 |
肿瘤学 | 345篇 |
出版年
2023年 | 17篇 |
2022年 | 48篇 |
2021年 | 86篇 |
2020年 | 37篇 |
2019年 | 50篇 |
2018年 | 93篇 |
2017年 | 69篇 |
2016年 | 69篇 |
2015年 | 92篇 |
2014年 | 126篇 |
2013年 | 145篇 |
2012年 | 324篇 |
2011年 | 335篇 |
2010年 | 166篇 |
2009年 | 173篇 |
2008年 | 336篇 |
2007年 | 328篇 |
2006年 | 272篇 |
2005年 | 281篇 |
2004年 | 304篇 |
2003年 | 274篇 |
2002年 | 251篇 |
2001年 | 83篇 |
2000年 | 84篇 |
1999年 | 85篇 |
1998年 | 68篇 |
1997年 | 55篇 |
1996年 | 42篇 |
1995年 | 50篇 |
1994年 | 29篇 |
1993年 | 25篇 |
1992年 | 44篇 |
1991年 | 37篇 |
1990年 | 45篇 |
1989年 | 40篇 |
1988年 | 35篇 |
1987年 | 27篇 |
1986年 | 31篇 |
1985年 | 29篇 |
1984年 | 29篇 |
1983年 | 22篇 |
1982年 | 11篇 |
1981年 | 21篇 |
1978年 | 11篇 |
1974年 | 8篇 |
1972年 | 11篇 |
1971年 | 11篇 |
1970年 | 10篇 |
1968年 | 9篇 |
1967年 | 8篇 |
排序方式: 共有4890条查询结果,搜索用时 15 毫秒
1.
2.
Renaud Snanoudj Nassim Kamar Elisabeth Cassuto Sophie Caillard Marie Metzger Pierre Merville Antoine Thierry Isabelle Jollet Philippe Grimbert Dany Anglicheau Marc Hazzan Gabriel Choukroun Bruno Hurault De Ligny Bénedicte Janbon Vincent Vuiblet Anne Devys Yann Le Meur Michel Delahousse Jean-Luc Taupin 《Kidney international》2019,95(6):1471-1485
3.
Efficacy of intensive multitherapy for patients with type 2 diabetes mellitus: a randomized controlled trial 总被引:1,自引:1,他引:0 下载免费PDF全文
4.
Background:
The results of a pilot colorectal cancer screening programme by biennial immunochemical faecal occult blood test (FOBT) are reported.Methods:
All residents aged between 50 and 69 years in the Italian province of Lecco were invited to have a FOBT. Those with a positive result were offered colonoscopy. FOBT uptake and compliance with colonoscopy were assessed. Detection rate and positive predictive value (PPV) for cancer and adenoma were calculated. Tumour stages were compared between screen‐detected cancers and other colorectal cancers diagnosed within the target age group.Results:
Some 38 693 (49·6 per cent) of 78 083 individuals had a FOBT and 2392 (6·2 per cent) had a positive result. Colorectal cancer was diagnosed in 4·6 per cent and advanced adenoma in 32·7 per cent. PPVs were 4·0 per cent for cancer, 28·1 per cent for advanced adenoma and 36·6 per cent for any adenoma. There was a significant difference in incidence of stage III/IV disease between screened and non‐screened cohorts. Compliance for colonoscopy was 92·0 per cent. Major determinants of compliance were age less than 59 years, female sex, high education level and non‐manual work.Conclusion:
These results justify extension of colorectal cancer screening to other regions of Italy. Copyright © 2009 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. 相似文献5.
Erdosteine was introduced in the market as a mucolytic agent for chronic pulmonary diseases more than 10 years ago. The drug contains two blocked sulphydryl groups one of which, after hepatic metabolization and opening of the thiolactone ring, becomes available both for the mucolytic and free radical scavenging and antioxidant activity too. There are several experimental evidences which support the protective effect of erdosteine in acute injury induced by a variety of pharmacological or noxious agents, mediated by products of oxidative stress. Experimental data in animal assigned to receive the noxious agent evidence that co-treatment with erdosteine increases the tissue antioxidant enzyme activities such as superoxide dismutase, catalase and glutathione peroxidase, compared with the toxic agent alone; meanwhile erdosteine decreases the tissue level of nitric oxide, xanthine oxidase, which catalyze oxygen-free radical production. In summary, erdosteine prevents the accumulation of free oxygen radicals when their production is accelerated and increases antioxidant cellular protective mechanisms. The final result is a protective effect on tissues which reduces lipid peroxidation, neutrophil infiltration or cell apoptosis mediated by noxious agents. Recent positive clinical trials in humans seem to fulfill the impressive promises that theory and experimental research have put forward. 相似文献
6.
7.
Sandrine Souverain Chin Eap Jean-Luc Veuthey Serge Rudaz 《Clinical chemistry and laboratory medicine》2003,41(12):1615-1621
Methadone (MTD) is a chiral drug widely used for the treatment of opioid dependence for which a rapid analytical method for the determination of each enantiomer would be advantageous. In order to improve method sensitivity and to automate the entire analytical process, a column-switching configuration has been developed. An online extraction system coupled to a cellulose-based chiral stationary phase (CSP), namely Chiralcel OJ-R, was used and detection was performed by mass spectrometry. Fifty microl of plasma were injected into the liquid chromatography-mass spectrometry (LC-MS) system after addition of acetonitrile (ACN) containing methadone deuterated D9 (MTD-D9) (internal standard) and centrifugation. For the rapid extraction step, a large particle size support was selected. A baseline separation of MTD enantiomers was obtained in less than 12 min. Trueness and precision were evaluated with control samples at 500 ng/ml of (R,S)-methadone. Trueness values were 106.6% and 103.0% for (R)-MTD and (S)-MTD, respectively, with a coefficient of variation inferior to 2.5% for both compounds. Finally, a good concordance was found using this method for analysis of plasma samples from patients in maintenance treatment as compared to a previously described HPLC-UV method after liquid-liquid extraction. 相似文献
8.
9.
Claudio Babiloni Giuliano Binetti Emanuele Cassetta Gloria Dal Forno Claudio Del Percio Florinda Ferreri Raffaele Ferri Giovanni Frisoni Koichi Hirata Bartolo Lanuzza Carlo Miniussi Davide V Moretti Flavio Nobili Guido Rodriguez Gian Luca Romani Serenella Salinari Paolo M Rossini 《Clinical neurophysiology》2006,117(2):252-268
OBJECTIVE: The present study tested the hypothesis that cortical electroencephalographic (EEG) rhythms. change across normal elderly (Nold), mild cognitive impairment (MCI), and Alzheimer's disease (AD) subjects as a function of the global cognitive level. METHODS: Resting eyes-closed EEG data were recorded in 155 MCI, 193 mild AD, and 126 age-matched Nold subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. RESULTS: Occipital delta and alpha 1 sources in parietal, occipital, temporal, and 'limbic' areas had an intermediate magnitude in MCI subjects compared to mild AD and Nold subjects. These five EEG sources presented both linear and nonlinear (linear, exponential, logarithmic, and power) correlations with the global cognitive level (as revealed by mini mental state examination score) across all subjects. CONCLUSIONS: Cortical EEG rhythms change in pathological aging as a function of the global cognitive level. SIGNIFICANCE: The present functional data on large populations support the 'transitional hypothesis' of a shadow zone across normality, pre-clinical stage of dementia (MCI), and AD. 相似文献
10.
Jean-Luc Garrigue Philippe Catroux Jacques Leclaire 《Clinical reviews in allergy & immunology》1995,13(3):189-200
Conclusion The search for a link between cellular and molecular events involved in delayed-type CHS reactions and the early molecular
activation of xenobiotics is a new field of research. It should largely contribute to the debate on the best way forward for
predictive toxicology in general. 相似文献