全文获取类型
收费全文 | 5613篇 |
免费 | 500篇 |
国内免费 | 31篇 |
专业分类
耳鼻咽喉 | 98篇 |
儿科学 | 292篇 |
妇产科学 | 231篇 |
基础医学 | 706篇 |
口腔科学 | 98篇 |
临床医学 | 591篇 |
内科学 | 1074篇 |
皮肤病学 | 115篇 |
神经病学 | 420篇 |
特种医学 | 415篇 |
外科学 | 602篇 |
综合类 | 159篇 |
一般理论 | 2篇 |
预防医学 | 422篇 |
眼科学 | 100篇 |
药学 | 324篇 |
中国医学 | 4篇 |
肿瘤学 | 491篇 |
出版年
2022年 | 23篇 |
2021年 | 51篇 |
2020年 | 44篇 |
2019年 | 70篇 |
2018年 | 93篇 |
2017年 | 60篇 |
2016年 | 102篇 |
2015年 | 100篇 |
2014年 | 127篇 |
2013年 | 172篇 |
2012年 | 239篇 |
2011年 | 266篇 |
2010年 | 177篇 |
2009年 | 150篇 |
2008年 | 260篇 |
2007年 | 325篇 |
2006年 | 276篇 |
2005年 | 274篇 |
2004年 | 237篇 |
2003年 | 245篇 |
2002年 | 208篇 |
2001年 | 173篇 |
2000年 | 155篇 |
1999年 | 153篇 |
1998年 | 115篇 |
1997年 | 128篇 |
1996年 | 120篇 |
1995年 | 102篇 |
1994年 | 80篇 |
1993年 | 88篇 |
1992年 | 113篇 |
1991年 | 144篇 |
1990年 | 111篇 |
1989年 | 113篇 |
1988年 | 117篇 |
1987年 | 101篇 |
1986年 | 82篇 |
1985年 | 85篇 |
1984年 | 61篇 |
1983年 | 47篇 |
1982年 | 44篇 |
1981年 | 42篇 |
1980年 | 38篇 |
1979年 | 45篇 |
1978年 | 39篇 |
1977年 | 38篇 |
1976年 | 26篇 |
1975年 | 28篇 |
1973年 | 30篇 |
1972年 | 39篇 |
排序方式: 共有6144条查询结果,搜索用时 31 毫秒
1.
Isolated patellofemoral arthritis is an increasingly recognized entity, and is usually associated with previous patellofemoral dysplasia or instability. Patellofemoral arthroplasty (PFA) has evolved significantly in recent years, both in terms of implant design and importantly in the understanding of appropriate patient selection. This review outlines the indications and investigations for PFA, provides a brief history of the development of contemporary implants, and presents the clinical outcomes for the prostheses most commonly used in the UK. In addition, it provides a detailed surgical technique for implantation of an onlay implant, with tips on how to optimize patellofemoral biomechanics and thus achieve a consistently good outcome. 相似文献
2.
3.
4.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
5.
A K Konstantinidis S J Barton I Sayers I A Yang J L Lordan S Rorke J B Clough S T Holgate J W Holloway 《The European respiratory journal》2007,30(1):40-47
Interleukin (IL)-13 plays a central role in asthma pathogenesis by binding to the IL-13 receptor, which is a heterodimer composed of the IL-13 receptor alpha1 subunit (IL-13Ralpha1) and IL-4Ralpha. The genetic diversity at the IL-13Ralpha1 gene (IL13RA1) locus on chromosome Xq24 was characterised and the association of identified polymorphisms with asthma and atopy phenotypes examined. The promoter and coding region of IL13RA1 were screened for common genetic variants, and polymorphisms found were genotyped in a large cohort of 341 asthmatic Caucasian families (each containing at least two asthmatic siblings) and 182 nonasthmatic control subjects. Genetic association was determined using case-control and transmission disequilibrium test analyses. Two common polymorphisms were identified, a newly found thymidine (T) to guanine (G) transition of nucleotide -281 (-281T>G) single nucleotide polymorphism in the IL13RA1 promoter and the previously described 1365A>G variant in the IL13RA1 proximal 3' untranslated region. No significant association of either -281T>G or 1365A>G with risk of asthma or atopy phenotypes was found, apart from a suggestive association between the IL13RA1 -281T/1365A haplotype and raised total serum immunoglobulin E levels in adult female asthmatics. These findings indicate that the interleukin-13 receptor alpha1 subunit gene -281T>G and 1365A>G polymorphisms do not contribute to asthma susceptibility or severity, although the interleukin-13 receptor alpha1 subunit gene locus might be involved in the control of immunoglobulin E production. 相似文献
6.
Metabolism is one of the major determinants for age-related changes in susceptibility to chemicals. Aldehydes are highly reactive molecules present in the environment that also can be produced during biotransformation of xenobiotics and endogenous metabolism. Although the lung is a major target for aldehyde toxicity, early development of aldehyde dehydrogenases (ALDHs) in lung has been poorly studied. The expression of ALDH in liver and lung across ages (postnatal day 1, 8, 22, and 60) was investigated in Wistar-Han rats. In adult, the majority of hepatic ALDH activity was found in mitochondria, while cytosolic ALDH activity was the highest contributor in lung. Total aldehyde oxidation capability in liver increases with age, but stays constant in lung. These overall developmental profiles of ALDH expression in a tissue appear to be determined by the different composition of ALDH isoforms within the tissue and their independent temporal and tissue-specific development. ALDH2 showed the most notable tissue-specific development. Hepatic ALDH2 was increased with age, while the pulmonary form did not. ALDH1 was at its maximum value at postnatal day 1 (PND1) and decreased thereafter both in liver and lung. ALDH3 increased with age in liver and lung, although ALDH3A1 was only detectible in lung. Collectively, the present study indicates that, in the case of aldehyde exposure, the in vivo responses would be tissue and age dependent. 相似文献
7.
8.
9.