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   2534604篇
  免费   208915篇
  国内免费   4940篇
耳鼻咽喉   36008篇
儿科学   77067篇
妇产科学   66233篇
基础医学   355162篇
口腔科学   70965篇
临床医学   232632篇
内科学   501660篇
皮肤病学   50445篇
神经病学   217737篇
特种医学   102888篇
外国民族医学   899篇
外科学   385507篇
综合类   58000篇
现状与发展   2篇
一般理论   1119篇
预防医学   202675篇
眼科学   59612篇
药学   188197篇
  5篇
中国医学   4600篇
肿瘤学   137046篇
  2019年   20710篇
  2018年   28428篇
  2017年   21943篇
  2016年   24042篇
  2015年   27226篇
  2014年   39274篇
  2013年   58845篇
  2012年   80587篇
  2011年   84680篇
  2010年   49625篇
  2009年   47540篇
  2008年   79904篇
  2007年   84746篇
  2006年   85349篇
  2005年   83219篇
  2004年   80019篇
  2003年   76770篇
  2002年   75529篇
  2001年   113853篇
  2000年   117591篇
  1999年   99784篇
  1998年   29794篇
  1997年   27055篇
  1996年   26784篇
  1995年   25868篇
  1994年   24256篇
  1993年   22578篇
  1992年   80085篇
  1991年   77034篇
  1990年   74120篇
  1989年   71353篇
  1988年   66342篇
  1987年   65236篇
  1986年   61789篇
  1985年   58877篇
  1984年   44859篇
  1983年   38218篇
  1982年   23650篇
  1981年   21028篇
  1979年   41644篇
  1978年   29353篇
  1977年   24679篇
  1976年   23165篇
  1975年   24209篇
  1974年   29867篇
  1973年   28253篇
  1972年   26360篇
  1971年   24278篇
  1970年   22834篇
  1969年   21150篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.

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   
102.
To evaluate the changes in alveolar contour after guided bone regeneration (GBR) with two different combinations of biomaterials in dehiscence defects arou  相似文献   
103.
104.
105.
106.
107.
108.
109.
Porocarcinoma is an unusual, locally aggressive and potentially fatal neoplasm. Several cutaneous malignancies have been described in association with porocarcinoma, including squamous cell carcinoma, basal cell carcinoma and tricholemmal carcinoma. Previous reports have indicated that the occurrence of malignant tumours in combination with porocarcinoma is extremely rare, in particular with regard to Bowen disease (BD). We report an uncommon case of porocarcinoma occurring synchronously in a single BD lesion in a 63‐year‐old woman with multiple BD lesions. The clinical and histological findings confirmed this diagnosis.  相似文献   
110.
Advancement in microelectromechanical system has facilitated the microfabrication of polymeric substrates and the development of the novel class of controlled drug delivery devices. These vehicles have specifically tailored three dimensional physical and chemical features which together, provide the capacity to target cell, stimulate unidirectional controlled release of therapeutics and augment permeation across the barriers. Apart from drug delivery devices microfabrication technology’s offer exciting prospects to generate biomimetic gastrointestinal tract models. BioMEMS are capable of analysing biochemical liquid sample like solution of metabolites, macromolecules, proteins, nucleic acid, cells and viruses. This review summarized multidisciplinary application of biomedical microelectromechanical systems in drug delivery and its potential in analytical procedures.  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