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   2398660篇
  免费   200803篇
  国内免费   6313篇
耳鼻咽喉   34440篇
儿科学   73133篇
妇产科学   63222篇
基础医学   337907篇
口腔科学   68008篇
临床医学   219232篇
内科学   472627篇
皮肤病学   48160篇
神经病学   202089篇
特种医学   97088篇
外国民族医学   898篇
外科学   363455篇
综合类   60902篇
现状与发展   7篇
一般理论   980篇
预防医学   192397篇
眼科学   56080篇
药学   180493篇
  31篇
中国医学   5920篇
肿瘤学   128707篇
  2018年   25104篇
  2017年   19653篇
  2016年   21442篇
  2015年   24523篇
  2014年   35034篇
  2013年   52179篇
  2012年   70540篇
  2011年   74451篇
  2010年   43876篇
  2009年   41957篇
  2008年   70158篇
  2007年   74563篇
  2006年   75421篇
  2005年   73423篇
  2004年   70396篇
  2003年   68076篇
  2002年   67239篇
  2001年   113199篇
  2000年   117194篇
  1999年   98987篇
  1998年   28254篇
  1997年   25997篇
  1996年   25771篇
  1995年   24892篇
  1994年   23376篇
  1993年   21729篇
  1992年   79552篇
  1991年   76567篇
  1990年   73714篇
  1989年   70963篇
  1988年   65942篇
  1987年   64901篇
  1986年   61420篇
  1985年   58450篇
  1984年   44254篇
  1983年   37675篇
  1982年   22898篇
  1981年   20339篇
  1979年   41329篇
  1978年   29000篇
  1977年   24350篇
  1976年   22841篇
  1975年   23977篇
  1974年   29652篇
  1973年   28047篇
  1972年   26232篇
  1971年   24155篇
  1970年   22754篇
  1969年   21091篇
  1968年   19139篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.

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   
92.
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   
93.
94.
95.
96.
97.
98.
99.
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   
100.
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