全文获取类型
收费全文 | 31216篇 |
免费 | 2434篇 |
国内免费 | 87篇 |
学科分类
医药卫生 | 33737篇 |
出版年
2023年 | 160篇 |
2022年 | 152篇 |
2021年 | 553篇 |
2020年 | 444篇 |
2019年 | 779篇 |
2018年 | 811篇 |
2017年 | 601篇 |
2016年 | 731篇 |
2015年 | 816篇 |
2014年 | 1043篇 |
2013年 | 1590篇 |
2012年 | 2179篇 |
2011年 | 2212篇 |
2010年 | 1227篇 |
2009年 | 1108篇 |
2008年 | 2047篇 |
2007年 | 2186篇 |
2006年 | 2172篇 |
2005年 | 2053篇 |
2004年 | 1930篇 |
2003年 | 1845篇 |
2002年 | 1743篇 |
2001年 | 333篇 |
2000年 | 289篇 |
1999年 | 312篇 |
1998年 | 425篇 |
1997年 | 302篇 |
1996年 | 304篇 |
1995年 | 290篇 |
1994年 | 241篇 |
1993年 | 232篇 |
1992年 | 201篇 |
1991年 | 162篇 |
1990年 | 144篇 |
1989年 | 156篇 |
1988年 | 146篇 |
1987年 | 108篇 |
1986年 | 135篇 |
1985年 | 150篇 |
1984年 | 115篇 |
1983年 | 130篇 |
1982年 | 147篇 |
1981年 | 138篇 |
1980年 | 145篇 |
1979年 | 67篇 |
1978年 | 72篇 |
1977年 | 59篇 |
1976年 | 73篇 |
1975年 | 53篇 |
1974年 | 51篇 |
排序方式: 共有10000条查询结果,搜索用时 343 毫秒
1.
Marike Gabrielson Mattias Hammarström Magnus Bäcklund Jenny Bergqvist Kristina Lång Ann H Rosendahl Signe Borgquist Roxanna Hellgren Kamila Czene Per Hall 《International journal of cancer. Journal international du cancer》2023,152(11):2362-2372
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
2.
3.
Factors predicting the development of pressure ulcers in an at‐risk population who receive standardized preventive care: secondary analyses of a multicentre randomised controlled trial 下载免费PDF全文
4.
Alessia Scarselli Silvia Di Cesare Claudia Capponi Simona Cascioli Maria L. Romiti Gigliola Di Matteo Alessandra Simonetti Paolo Palma Andrea Finocchi Barbarella Lucarelli Rita M. Pinto Ippolita Rana Giuseppe Palumbo Maurizio Caniglia Paolo Rossi Rita Carsetti Caterina Cancrini Alessandro Aiuti 《Journal of clinical immunology》2015,35(4):373-383
5.
6.
7.
8.
Femoral access‐related complications during percutaneous transcatheter aortic valve implantation comparing single versus double Prostar XL device closure 下载免费PDF全文
9.
10.