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   1707119篇
  免费   127750篇
  国内免费   3786篇
耳鼻咽喉   21863篇
儿科学   56112篇
妇产科学   46588篇
基础医学   243362篇
口腔科学   49124篇
临床医学   152865篇
内科学   336142篇
皮肤病学   38947篇
神经病学   132712篇
特种医学   64461篇
外国民族医学   242篇
外科学   259087篇
综合类   38978篇
现状与发展   4篇
一般理论   547篇
预防医学   125701篇
眼科学   40352篇
药学   124819篇
  7篇
中国医学   4489篇
肿瘤学   102253篇
  2021年   13003篇
  2019年   13851篇
  2018年   20524篇
  2017年   15781篇
  2016年   17190篇
  2015年   19425篇
  2014年   26722篇
  2013年   38928篇
  2012年   53965篇
  2011年   56797篇
  2010年   33365篇
  2009年   31064篇
  2008年   52641篇
  2007年   55966篇
  2006年   56334篇
  2005年   53487篇
  2004年   51600篇
  2003年   49003篇
  2002年   47214篇
  2001年   92222篇
  2000年   94082篇
  1999年   77236篇
  1998年   19832篇
  1997年   17355篇
  1996年   17463篇
  1995年   16829篇
  1994年   15367篇
  1993年   14142篇
  1992年   57450篇
  1991年   55347篇
  1990年   53027篇
  1989年   50825篇
  1988年   46217篇
  1987年   45014篇
  1986年   42294篇
  1985年   40088篇
  1984年   29465篇
  1983年   25002篇
  1982年   13983篇
  1979年   25590篇
  1978年   17614篇
  1977年   14881篇
  1976年   13857篇
  1975年   14534篇
  1974年   17617篇
  1973年   16928篇
  1972年   15676篇
  1971年   14440篇
  1970年   13424篇
  1969年   12510篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
71.
72.
73.
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   
74.
75.
Annals of Nuclear Medicine - The Response Evaluation Criteria In Solid Tumors (RECIST) is the most used radiological method for evaluating response after peptide receptor radionuclide therapy...  相似文献   
76.

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   
77.
78.
79.
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   
80.
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   
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