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   2532篇
  免费   128篇
  国内免费   8篇
耳鼻咽喉   5篇
儿科学   85篇
妇产科学   38篇
基础医学   319篇
口腔科学   56篇
临床医学   210篇
内科学   579篇
皮肤病学   24篇
神经病学   213篇
特种医学   50篇
外科学   414篇
综合类   7篇
一般理论   1篇
预防医学   173篇
眼科学   24篇
药学   139篇
中国医学   3篇
肿瘤学   328篇
  2023年   12篇
  2022年   27篇
  2021年   49篇
  2020年   19篇
  2019年   40篇
  2018年   61篇
  2017年   49篇
  2016年   49篇
  2015年   55篇
  2014年   70篇
  2013年   109篇
  2012年   169篇
  2011年   180篇
  2010年   93篇
  2009年   96篇
  2008年   157篇
  2007年   129篇
  2006年   116篇
  2005年   114篇
  2004年   120篇
  2003年   88篇
  2002年   114篇
  2001年   59篇
  2000年   73篇
  1999年   57篇
  1998年   22篇
  1997年   19篇
  1996年   21篇
  1994年   22篇
  1993年   17篇
  1992年   40篇
  1991年   28篇
  1990年   35篇
  1989年   29篇
  1988年   27篇
  1987年   26篇
  1986年   20篇
  1985年   16篇
  1984年   13篇
  1983年   15篇
  1982年   11篇
  1979年   19篇
  1977年   9篇
  1975年   11篇
  1974年   13篇
  1973年   11篇
  1972年   9篇
  1969年   13篇
  1968年   9篇
  1965年   9篇
排序方式: 共有2668条查询结果,搜索用时 15 毫秒
991.
Diabetic retinopathy (DR) is a leading cause of visual impairment in working age in industrialized countries. It is classified as non-proliferative (mild, moderate or severe) and proliferative, with diabetic macular oedema potentially developing at any of these stages. The prevalence and incidence of DR increase with diabetes duration and worsening of metabolic and blood pressure control. Current approaches to prevent and/or treat DR include optimized control of blood glucose and blood pressure and screening for early identification of high-risk, although still asymptomatic, retinal lesions. Results from recent clinical trials suggest a role for blockers of the renin-angiotensin system (angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers) and for fenofibrate in reducing progression and/or inducing regression of mild-to-moderate non-proliferative DR. Intravitreal administration of anti-vascular endothelial growth factor (VEGF) agents was shown to reduce visual loss in more advanced stages of DR, especially in macular oedema.  相似文献   
992.
993.

Purpose

To evaluate activity staging of Crohn's disease (CD) measured with MR-enterography using ileoscopy as reference standard.

Materials and methods

A prospective study was made of 61 patients with CD. All patients underwent MR-enterography and ileoscopy. MRI activity was measured by means of an ad hoc developed score, as well as by analysis of the imaging findings, and was compared with the SES-CD score obtained via ileoscopy. Examinations were performed using a 1.0 T scanner.

Results

MRI score discriminates between active and inactive disease with an area under the ROC curve of 0.941. Overall correlation with the standard reference SES-CD score was moderate to strong (Spearman's r = 0.62 p < 0.001).Agreement between both methods in staging patients with ileal CD as inactive, mild or moderate to severe was good (Cohen's κ = 0.60). Differences in means of the MRI activity scores of the three groups showed statistical significance (p < 0.01).

Conclusions

The MRI score is a reliable predictor of activity in ileal CD and can stage patients in a way comparable to endoscopy. 1.0 T scans are valid for performing radiological evaluation of ileal Crohn's disease.  相似文献   
994.
995.
996.
997.
998.
999.
The current standard therapeutic option for early stage breast cancer (EBC) employs a multimodality treatment approach including conservative surgery, radiotherapy, chemotherapy, and hormone therapy. The most common adjuvant radiotherapeutic strategy consists of external beam radiation therapy (EBRT) delivered to the whole breast using 1.8-2 Gy fractions given five times a week, up to a total dose of 45-50 Gy over a period of 5 weeks. In recent years, altered schedules employing larger dose per fraction delivered in fewer treatment sessions over a shorter overall treatment time began to be explored. We herein present clinical data on accelerated hypofractionated adjuvant whole-breast radiotherapy delivered on a daily basis for a total treatment time of 20 fractions. Between February 2005 and June 2009, a total of 463 patients underwent hypofractionated accelerated adjuvant radiation after conservative surgery for early breast cancer (pathological stage pTis, pT1 or pT2, pN0-N1). The basic course of radiotherapy consisted of 45 Gy, to the whole breast in 20 fractions with 2.25 Gy/fraction; an additional daily boost dose of 0.25 Gy was concomitantly delivered, to the lumpectomy cavity, for an additional total dose of 5 Gy. The cumulative nominal dose was 50 Gy. At follow-up, patients were examined at 3 and 6 months after the end of radiotherapy and twice a year afterward. Toxicity was scored according to the Common Terminology Criteria for Adverse Events, using the Radiation Therapy Oncology Group /European Organization for Research and Treatment of Cancer toxicity scale. Cosmetic results were assessed in agreement with the Harvard criteria. All the 463 patients treated with the accelerated hypofractionated adjuvant whole-breast radiotherapy schedule achieved at least 6 months' follow-up and subsequently were considered for the present analysis. With a median follow-up of 27 months, 5-year DFS is 93.1%. Only three patients experienced disease recurrence: two of them with an axillary nodal relapse; one patient with systemic spread. No local relapse occurred. No major toxicities (grade 3 or more) were detected during follow-up. Only 2% of the patients experienced grade 3 skin toxicity at the very end of the radiotherapy course. Cosmetic result was assessed and scored at 6 months, 1 year, 2 years: 100% of patients showed excellent or good cosmetic result. The explored accelerated hypofractionated adjuvant radiotherapeutic approach for early breast cancer with concomitant photon boost seems to be feasible providing consistent clinical results with excellent short-to-medium-term toxicity profile.  相似文献   
1000.

Background  

Endoluminal fundoplcation (ELF) with EsophyX™ is a new attractive investigational procedure for the control of gastroesophageal reflux disease (GERD). The aim of this work is to evaluate the short-term results of Nissen fundoplication (NF) after failure of ELF.  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