全文获取类型
收费全文 | 1456篇 |
免费 | 100篇 |
国内免费 | 62篇 |
专业分类
耳鼻咽喉 | 23篇 |
儿科学 | 49篇 |
妇产科学 | 13篇 |
基础医学 | 171篇 |
口腔科学 | 46篇 |
临床医学 | 156篇 |
内科学 | 256篇 |
皮肤病学 | 15篇 |
神经病学 | 202篇 |
特种医学 | 160篇 |
外科学 | 141篇 |
综合类 | 26篇 |
一般理论 | 2篇 |
预防医学 | 122篇 |
眼科学 | 17篇 |
药学 | 155篇 |
中国医学 | 3篇 |
肿瘤学 | 61篇 |
出版年
2022年 | 8篇 |
2021年 | 25篇 |
2020年 | 13篇 |
2019年 | 26篇 |
2018年 | 28篇 |
2017年 | 20篇 |
2016年 | 23篇 |
2015年 | 35篇 |
2014年 | 49篇 |
2013年 | 54篇 |
2012年 | 68篇 |
2011年 | 78篇 |
2010年 | 68篇 |
2009年 | 66篇 |
2008年 | 55篇 |
2007年 | 97篇 |
2006年 | 68篇 |
2005年 | 68篇 |
2004年 | 51篇 |
2003年 | 34篇 |
2002年 | 35篇 |
2001年 | 36篇 |
2000年 | 36篇 |
1999年 | 34篇 |
1998年 | 35篇 |
1997年 | 45篇 |
1996年 | 34篇 |
1995年 | 27篇 |
1994年 | 13篇 |
1993年 | 28篇 |
1992年 | 13篇 |
1991年 | 19篇 |
1990年 | 30篇 |
1989年 | 36篇 |
1988年 | 16篇 |
1987年 | 22篇 |
1986年 | 12篇 |
1985年 | 16篇 |
1984年 | 15篇 |
1983年 | 12篇 |
1982年 | 14篇 |
1981年 | 7篇 |
1980年 | 15篇 |
1979年 | 10篇 |
1978年 | 9篇 |
1976年 | 7篇 |
1974年 | 13篇 |
1972年 | 10篇 |
1971年 | 8篇 |
1970年 | 6篇 |
排序方式: 共有1618条查询结果,搜索用时 15 毫秒
1.
The initial management of bladder outflow obstruction typically related to benign prostatic hyperplasia (BPH) falls to a large extent within the remit of general practice. Referral onwards to secondary care typically arises following the failure to respond to conservative measures or when complications have supervened; the most significant of which is urinary retention. In the hospital setting, anaesthesia, constipation and immobility are the common precipitants. What follows is a practical guide to the management of these situations and provides an overview of the conservative, medical, minimally invasive and surgical treatments available. 相似文献
2.
3.
Davangere P Devanand Christian G Habeck Matthias H Tabert Nikolaos Scarmeas Gregory H Pelton James R Moeller Brett D Mensh Tyler Tarabula Ronald L Van Heertum Yaakov Stern 《Neuropsychopharmacology》2006,31(6):1327-1334
Temporoparietal and posterior cingulate metabolism deficits characterize patients with Alzheimer's disease (AD). A H(2)(15)O resting PET scan covariance pattern, derived by using multivariate techniques, was previously shown to discriminate 17 mild AD patients from 16 healthy controls. This AD covariance pattern revealed hypoperfusion in bilateral inferior parietal lobule and cingulate; and left middle frontal, inferior frontal, precentral, and supramarginal gyri. The AD pattern also revealed hyperperfusion in bilateral insula, lingual gyri, and cuneus; left fusiform and superior occipital gyri; and right parahippocampal gyrus and pulvinar. In an independent sample of 23 outpatients with mild cognitive impairment (MCI) followed at 6-month intervals, the AD pattern score was evaluated as a predictor of cognitive decline. In this MCI sample, an H2(15)O resting PET scan was carried out at baseline. Mean duration of follow-up was 48.8 (SD 15.5) months, during which time six of 23 MCI patients converted to AD. In generalized estimating equations (GEE) analyses, controlling for age, sex, education, and baseline neuropsychological scores, increased AD pattern score was associated with greater decline in each neuropsychological test score over time (Mini Mental State Exam, Selective Reminding Test delayed recall, Animal Naming, WAIS-R digit symbol; Ps<0.01-0.001). In summary, a resting PET covariance pattern previously reported to discriminate AD patients from control subjects was applied prospectively to an independent sample of MCI patients and found to predict cognitive decline. Independent replication in larger samples is needed before clinical application can be considered. 相似文献
4.
5.
6.
7.
Background
There is currently an unprecedented expressed need and demand for estimates of maternal mortality in developing countries. This has been stimulated in part by the creation of a Millennium Development Goal that will be judged partly on the basis of reductions in maternal mortality by 2015. 相似文献8.
9.
Bruce R. Thorley Julie Milland Dale Christiansen Marc B. Lanteri Beth McInnes Ingrid Moeller Pierre Rivailler Branka Horvat Chantal Rabourdin-Combe Denis Gerlier Ian F. C. McKenzie Bruc. E. E. Loveland 《European journal of immunology》1997,27(3):726-734
CD46 (membrane cofactor protein) is a human cell-surface regulator of activated complement and a receptor for the measles virus. A CD46 transgenic mouse line with an expression pattern similar to that of human tissues has been produced, to develop an animal model of (i) the control of complement activation by complement regulators in hyperacute rejection of xenografts, and (ii) measles virus infection. The mouse line was made using a CD46 minigene that includes promoter sequence and the first two introns of genomic CD46, which was coinjected into mouse ova with chicken lysozyme matrix attachment region DNA. A high level of CD46 expression in homozygotic transgenic mice was obtained with spleen cells having approximately 75% of the level found on human peripheral blood mononuclear cells. CD46 was detected in all tissues examined by immunohistochemistry, radioimmunoassay and Western blotting, showing that these mice were suitable for transplantation and measles virus infection studies. It also indicated that the transgene included the important regulatory elements of the CD46 promoter. Transgenic spleen cells were significantly protected in vitro from human complement activated by either the classical or alternative pathways and from alternative pathway rat complement. Furthermore, transgenic mouse hearts transplanted to rats regulated complement deposition in an in vivo model of antibody-dependent hyperacute xenograft rejection. Similar to human lymphocytes, transgenic lymphoblasts could be infected in vitro with measles virus; infected cells expressed viral proteins and produced infectious viral particles. The data demonstrate the suitability of this minigene for obtaining high-level CD46 expression sufficient for enhanced resistance of transgenic cells to complement attack and for obtaining wide tissue distribution of CD46, analogous to human tissues and, therefore, useful for comparative studies. 相似文献
10.