全文获取类型
收费全文 | 20607篇 |
免费 | 1503篇 |
国内免费 | 68篇 |
专业分类
耳鼻咽喉 | 242篇 |
儿科学 | 679篇 |
妇产科学 | 486篇 |
基础医学 | 2994篇 |
口腔科学 | 956篇 |
临床医学 | 2386篇 |
内科学 | 3935篇 |
皮肤病学 | 402篇 |
神经病学 | 2007篇 |
特种医学 | 416篇 |
外科学 | 1853篇 |
综合类 | 263篇 |
一般理论 | 12篇 |
预防医学 | 2451篇 |
眼科学 | 439篇 |
药学 | 1366篇 |
中国医学 | 89篇 |
肿瘤学 | 1202篇 |
出版年
2023年 | 197篇 |
2022年 | 387篇 |
2021年 | 738篇 |
2020年 | 449篇 |
2019年 | 670篇 |
2018年 | 704篇 |
2017年 | 515篇 |
2016年 | 520篇 |
2015年 | 618篇 |
2014年 | 811篇 |
2013年 | 1019篇 |
2012年 | 1627篇 |
2011年 | 1684篇 |
2010年 | 864篇 |
2009年 | 748篇 |
2008年 | 1329篇 |
2007年 | 1239篇 |
2006年 | 1190篇 |
2005年 | 1118篇 |
2004年 | 952篇 |
2003年 | 882篇 |
2002年 | 864篇 |
2001年 | 217篇 |
2000年 | 216篇 |
1999年 | 197篇 |
1998年 | 182篇 |
1997年 | 124篇 |
1996年 | 124篇 |
1995年 | 106篇 |
1994年 | 102篇 |
1993年 | 95篇 |
1992年 | 123篇 |
1991年 | 119篇 |
1990年 | 121篇 |
1989年 | 84篇 |
1988年 | 107篇 |
1987年 | 110篇 |
1986年 | 96篇 |
1985年 | 93篇 |
1984年 | 89篇 |
1983年 | 86篇 |
1982年 | 56篇 |
1981年 | 52篇 |
1980年 | 44篇 |
1979年 | 51篇 |
1978年 | 44篇 |
1977年 | 34篇 |
1973年 | 31篇 |
1972年 | 29篇 |
1970年 | 34篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Olaia Sardón Prado Eduardo G. Pérez-Yarza Ane Aldasoro Ruiz Javier Korta Murua Paula Corcuera Elósegui Javier Mintegui Aramburu José Ignacio Emparanza Knorr 《Archivos de bronconeumologia》2011,47(5):234-238
IntroductionThe fraction of exhaled nitric oxide (FENO) is considered an indirect marker of eosinophilic inflammation of the airway. In cooperative children, the usual method is a single breath. The impossibility of performing this in uncooperative children has led to the development of the online and offline tidal breathing technique. The objective of the study has been to analyse the relationship between the multiplebreath online FENO and the asthma predictive index (API) in children under the age of two.Material and methodsAn observational and cross-sectional study on a consecutive sample of boys and girls between 2 months and 2 years of age, over a period of 4 months. The post-prandial multiple breaths online FENO and flow spirometry between 40 and 60 ml/s, using a stationary chemiluminescence analyser (CLD 88 sp). The quantitative variables were: age, weight, IgE, eosinophilia, FENO, flow spirometry. The qualitative variables were: gender, atopic dermatitis, allergic rhinitis, food and medical allergies, family history of asthma and atopy, diagnosis and treatment. The relationship between API and FENO was analysed using the exact Fisher and Student t tests and the level of agreement between API and FENO using Cohen's Kappa. The relationship between eosinophilia, IgE, atopic dermatitis and FENO was also studied (exact Fisher and Student t tests).ResultsThe cohort consisted of 38 patients. The determinations were successfully carried out on 32 (84.21) of the cases. The mean age was 10.9 ± 5.06 months. The cases with a positive API had significantly higher FENO values than those with a negative API, with a level of agreement between API and FENO of 0.71.ConclusionsThere is a significant relationship and a good level of agreement between the online tidal breathing FENO and the API. 相似文献
992.
993.
994.
Patrícia S. Guerreiro Joana E. Coelho Inês Sousa-Lima Paula Macedo Luísa V. Lopes Tiago F. Outeiro Teresa F. Pais 《Neuromolecular medicine》2017,19(1):113-121
The protein α-synuclein (α-Syn) interferes with glucose and lipid uptake and also activates innate immune cells. However, it remains unclear whether α-Syn or its familial mutant forms contribute to metabolic alterations and inflammation in synucleinopathies, such as Parkinson’s disease (PD). Here, we address this issue in transgenic mice for the mutant A53T human α-Syn (α-SynA53T), a mouse model of synucleinopathies. At 9.5 months of age, mice overexpressing α-SynA53T (homozygous) had a significant reduction in weight, exhibited improved locomotion and did not show major motor deficits compared with control transgenic mice (heterozygous). At 17 months of age, α-SynA53T overexpression promoted general reduction in grip strength and deficient hindlimb reflex and resulted in severe disease and mortality in 50 % of the mice. Analysis of serum metabolites further revealed decreased levels of cholesterol, triglycerides and non-esterified fatty acids (NEFA) in α-SynA53T—overexpressing mice. In fed conditions, these mice also showed a significant decrease in serum insulin without alterations in blood glucose. In addition, assessment of inflammatory gene expression in the brain showed a significant increase in TNF-α mRNA but not of IL-1β induced by α-SynA53T overexpression. Interestingly, the brain mRNA levels of Sirtuin 2 (Sirt2), a deacetylase involved in both metabolic and inflammatory pathways, were significantly reduced. Our findings highlight the relevance of the mechanisms underlying initial weight loss and hyperactivity as early markers of synucleinopathies. Moreover, we found that changes in blood metabolites and decreased brain Sirt2 gene expression are associated with motor deficits. 相似文献
995.
996.
Marina Gonçalves Diniz Clarice Ferreira Galvão Paula Serelle Macedo Carolina Cavaliéri Gomes Ricardo Santiago Gomez 《Journal of oral pathology & medicine》2011,40(3):277-280
J Oral Pathol Med (2011) 40 : 277–280 The orthokeratinized odontogenic cyst (OOC) is an odontogenic cyst of unknown etiology. Clinical, histological, and biological differences are reported between keratocystic odontogenic tumor (KOT) and OOC. PTCH is a tumor suppressor gene related to sonic hedgehog (SHH) pathway important in embryological development. Considering that alterations in this pathway have been described in sporadic and nevoid basal cell syndrome‐associated KOT, we tested the hypothesis that OOC is also associated with loss of heterozygosity (LOH) of the PTCH gene. Seven samples of OOC and seven of KOT were included in the study. D9S287, D9S196, and D9S127 microsatellite markers located in the region of PTCH gene, at chromosome 9q, were investigated for LOH. There was loss in at least one locus in 5/7 KOT and in 4/7 OOC samples. The present finding demonstrates that, despite the existence of clinical, morphological, immunohistochemical, and biological behavior differences between OOC and KOT, both harbor similar genetic alterations at 9q. 相似文献
997.
998.
999.
1000.
Luis Manzano Juan de D. García-Díaz Carmen Suárez José Ma Mostaza Marc Cairols Enrique González-Sarmiento Alipio Mangas Rojas Paula Vieitez Miguel Ángel Sánchez-Zamorano Javier Zamora 《European Journal of Internal Medicine》2009,20(4):429-434
ObjectivesTo evaluate the prevalence of both non-calf intermittent claudication (IC) and classic IC in patients with no known atherosclerotic disease, and their accuracy to detect peripheral arterial disease (PAD).DesignCross sectional, observational study conducted at 96 internal medicine services.Materials and methods1487 outpatients with no known atherosclerotic disease, and either diabetes or a SCORE risk estimation of at least 3% were enrolled. IC was assessed using the Edinburgh Claudication Questionnaire and PAD was confirmed by an ankle-brachial index (ABI) < 0.9.ResultsOverall, 7.2% met criteria of classic and 5.8% of non-calf IC. PAD was diagnosed in 393 cases (26.4%). In these PAD patients, 17.8% exhibited classic and 13.2% non-calf IC. Both calf and non-calf IC had similar overall accuracy for detecting PAD. Considering both categories as a whole, the sensitivity of IC to predict a low ABI was 31% and the specificity 93%.ConclusionsNon-calf IC is comparable to classic IC for the diagnosis of PAD in patients with no known arterial disease. The systematic implementation of Edinburgh Claudication Questionnaire could be a valuable call-to-action to improve clinical evaluation of PAD, bearing in mind that PAD detected by either non-calf or classic IC must be confirmed by ABI testing. 相似文献