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   37866篇
  免费   5494篇
  国内免费   854篇
耳鼻咽喉   10篇
儿科学   1241篇
妇产科学   439篇
基础医学   4181篇
口腔科学   91篇
临床医学   3060篇
内科学   1016篇
皮肤病学   139篇
神经病学   104篇
特种医学   1505篇
外国民族医学   74篇
外科学   4766篇
综合类   4738篇
现状与发展   6篇
一般理论   1篇
预防医学   2337篇
眼科学   37篇
药学   2215篇
  29篇
中国医学   665篇
肿瘤学   17560篇
  2024年   102篇
  2023年   568篇
  2022年   1241篇
  2021年   2023篇
  2020年   1800篇
  2019年   1589篇
  2018年   1507篇
  2017年   1557篇
  2016年   1703篇
  2015年   2048篇
  2014年   2504篇
  2013年   2769篇
  2012年   2060篇
  2011年   2207篇
  2010年   1706篇
  2009年   1620篇
  2008年   1630篇
  2007年   1754篇
  2006年   1753篇
  2005年   1611篇
  2004年   1344篇
  2003年   1284篇
  2002年   1085篇
  2001年   947篇
  2000年   764篇
  1999年   677篇
  1998年   538篇
  1997年   529篇
  1996年   435篇
  1995年   364篇
  1994年   304篇
  1993年   253篇
  1992年   215篇
  1991年   204篇
  1990年   161篇
  1989年   141篇
  1988年   140篇
  1987年   133篇
  1986年   131篇
  1985年   142篇
  1984年   123篇
  1983年   88篇
  1982年   122篇
  1981年   102篇
  1980年   58篇
  1979年   57篇
  1978年   41篇
  1977年   29篇
  1976年   25篇
  1975年   10篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《Cancer radiothérapie》2022,26(4):611-615
In order to provide more convenient irradiation regimens for patient comfort, radiation facility organization and health expenses, new hypofractionated protocols have been evaluated. Moderately (dose/fraction: 2.3 to 3 Gy), then ultra (dose/fraction: 5.2 to 6.1 Gy) hypofractionated irradiations were first validated. The current question is: is it possible to go forward using extreme hypofractionated regimens (EHR) based on 1 to 3 fractions. Different irradiation techniques are under investigation. However, brachytherapy remains the smartest way to deliver a high dose in a small volume. We report prospective and retrospective study results which evaluated EHR for breast and prostate brachytherapy. While oncological outcome and toxicity profile appear extremely encouraging for low-risk breast cancer after a 1 to 4 fractions (6.25 to 20 Gy/fraction), the use of a single fraction of 19 to 23 Gy appears debatable for prostate cancer. Brachytherapy represents an emblematic example of EHR but longer follow-up and more mature results are awaited in order to specify the right indications and refine the EQD2 calculation method including new biological and technical factors.  相似文献   
2.
3.
4.
5.
Breast core biopsies are a standard component of the triple approach that includes clinical examination, imaging and tissue sampling. Conventional cores, diagnostic vacuum assisted biopsy and vacuum assisted excisions are established methods for sampling and managing breast lesions. It is important to be aware of the potential pitfalls in the technical handling and interpretation of the limited core biopsy samples. Here, we present a clinically oriented, well illustrated overview of the common diagnostic pitfalls based on the author's diagnostic and second opinion practice, emphasize the value of clinicopathological correlation and provide histological tips and clues with useful immunohistochemistry to aid the reporting pathologists in their daily interpretation of breast core biopsies.  相似文献   
6.
7.
8.
Tamoxifen prevents recurrence of breast cancer and is suggested for preventive risk-reducing therapy. Tamoxifen reduces mammographic density, a proxy for therapy response, but little is known about its effects in remodelling normal breast tissue. Our study, a substudy within the double-blinded dose-determination trial KARISMA, investigated tamoxifen-specific changes in breast tissue composition and histological markers in healthy women. We included 83 healthy women randomised to 6 months daily intake of 20, 10, 5, 2.5, 1 mg of tamoxifen or placebo. The groups were combined to “no dose” (0-1 mg), “low-dose” (2.5-5 mg) or “high-dose” (10-20 mg) of tamoxifen. Ultrasound-guided biopsies were collected before and after tamoxifen exposure. In each biopsy, epithelial, stromal and adipose tissues was quantified, and expression of epithelial and stromal Ki67, oestrogen receptor (ER) and progesterone receptor (PR) analysed. Mammographic density using STRATUS was measured at baseline and end-of-tamoxifen-exposure. We found that different doses of tamoxifen reduced mammographic density and glandular-epithelial area in premenopausal women and associated with reduced epithelium and increased adipose tissue. High-dose tamoxifen also decreased epithelial ER and PR expressions in premenopausal women. Premenopausal women with the greatest reduction in proliferation also had the greatest epithelial reduction. In postmenopausal women, high-dose tamoxifen decreased the epithelial area with no measurable density decrease. Tamoxifen at both low and high doses influences breast tissue composition and expression of histological markers in the normal breast. Our findings connect epithelial proliferation with tissue remodelling in premenopausal women and provide novel insights to understanding biological mechanisms of primary prevention with tamoxifen.  相似文献   
9.
10.
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