首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1695127篇
  免费   126491篇
  国内免费   3802篇
耳鼻咽喉   21744篇
儿科学   55688篇
妇产科学   46169篇
基础医学   241596篇
口腔科学   48785篇
临床医学   151621篇
内科学   334300篇
皮肤病学   38708篇
神经病学   131258篇
特种医学   63983篇
外国民族医学   242篇
外科学   257488篇
综合类   38956篇
现状与发展   4篇
一般理论   531篇
预防医学   124309篇
眼科学   40241篇
药学   123822篇
  7篇
中国医学   4477篇
肿瘤学   101491篇
  2021年   12826篇
  2019年   13549篇
  2018年   19996篇
  2017年   15248篇
  2016年   16667篇
  2015年   19000篇
  2014年   26303篇
  2013年   38022篇
  2012年   52849篇
  2011年   55552篇
  2010年   32847篇
  2009年   30755篇
  2008年   51641篇
  2007年   54926篇
  2006年   55368篇
  2005年   52634篇
  2004年   50852篇
  2003年   48265篇
  2002年   46511篇
  2001年   91861篇
  2000年   93714篇
  1999年   77050篇
  1998年   19757篇
  1997年   17296篇
  1996年   17421篇
  1995年   16768篇
  1994年   15309篇
  1993年   14102篇
  1992年   57455篇
  1991年   55327篇
  1990年   53013篇
  1989年   50792篇
  1988年   46170篇
  1987年   44981篇
  1986年   42254篇
  1985年   40019篇
  1984年   29374篇
  1983年   24925篇
  1982年   13903篇
  1979年   25544篇
  1978年   17579篇
  1977年   14918篇
  1976年   13881篇
  1975年   14571篇
  1974年   17641篇
  1973年   16954篇
  1972年   15684篇
  1971年   14464篇
  1970年   13441篇
  1969年   12526篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
European Journal of Orthopaedic Surgery & Traumatology - The goals of this study were to compare patient satisfaction and wound-related complications in patients receiving 2-octyl cyanoacrylate...  相似文献   
64.
65.

Purpose

Chest wall pain is an uncommon but bothersome late complication following lung stereotactic body radiation therapy. Despite numerous studies investigating predictors of chest wall pain, no clear consensus has been established for a chest wall constraint. The aim of our study was to investigate factors related to chest wall pain in a homogeneous group of patients treated at our institution.

Patients and methods

All 122 patients were treated with the same stereotactic body radiation therapy regimen of 48 Gy in three fractions, seen for at least 6 months of follow-up, and planned with heterogeneity correction. Chest wall pain was scored according to the Common Terminology Criteria for Adverse Events classification v3.0. Patient (age, sex, diabetes, osteoporosis), tumour (planning target volume, volume of the overlapping region between planning target volume and chest wall) and chest wall dosimetric parameters (volumes receiving at least 30, 40, and 50 Gy, the minimal doses received by the highest irradiated 1, 2, and 5 cm3, and maximum dose) were collected. The correlation between chest wall pain (grade 2 or higher) and the different parameters was evaluated using univariate and multivariate logistic regression.

Results

Median follow-up was 18 months (range: 6–56 months). Twelve patients out of 122 developed chest wall pain of any grade (seven with grade 1, three with grade 2 and two with grade 3 pain). In univariate analysis, only the volume receiving 30 Gy or more (P = 0.034) and the volume of the overlapping region between the planning target volume and chest wall (P = 0.038) significantly predicted chest wall pain, but these variables were later proved non-significant in multivariate regression.

Conclusion

Our analysis could not find any correlation between the studied parameters and chest wall pain. Considering our present study and the wide range of differing results from the literature, a reasonable conclusion is that a constraint for chest wall pain is yet to be defined.  相似文献   
66.
67.
68.
Individuals with sudden unilateral deafness offer a unique opportunity to study plasticity of the binaural auditory system in adult humans. Stimulation of the intact ear results in increased activity in the auditory cortex. However, there are no reports of changes at sub-cortical levels in humans. Therefore, the aim of the present study was to investigate changes in sub-cortical activity immediately before and after the onset of surgically induced unilateral deafness in adult humans. Click-evoked auditory brainstem responses (ABRs) to stimulation of the healthy ear were recorded from ten adults during the course of translabyrinthine surgery for the removal of a unilateral acoustic neuroma. This surgical technique always results in abrupt deafferentation of the affected ear. The results revealed a rapid (within minutes) reduction in latency of wave V (mean pre = 6.55 ms; mean post = 6.15 ms; p < 0.001). A latency reduction was also observed for wave III (mean pre = 4.40 ms; mean post = 4.13 ms; p < 0.001). These reductions in response latency are consistent with functional changes including disinhibition or/and more rapid intra-cellular signalling affecting binaurally sensitive neurons in the central auditory system. The results are highly relevant for improved understanding of putative physiological mechanisms underlying perceptual disorders such as tinnitus and hyperacusis.  相似文献   
69.
DNA methylation at CpG dinucleotides is an important epigenetic regulator common to virtually all mammalian cell types, but recent evidence indicates that during early postnatal development neuronal genomes also accumulate uniquely high levels of two alternative forms of methylation, non-CpG methylation and hydroxymethylation. Here we discuss the distinct landscape of DNA methylation in neurons, how it is established, and how it might affect the binding and function of protein readers of DNA methylation. We review studies of one critical reader of DNA methylation in the brain, the Rett syndrome protein methyl CpG-binding protein 2 (MeCP2), and discuss how differential binding affinity of MeCP2 for non-CpG and hydroxymethylation may affect the function of this methyl-binding protein in the nervous system.  相似文献   
70.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号