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   31354篇
  免费   1820篇
  国内免费   72篇
耳鼻咽喉   472篇
儿科学   1302篇
妇产科学   967篇
基础医学   4901篇
口腔科学   671篇
临床医学   2602篇
内科学   6514篇
皮肤病学   876篇
神经病学   2930篇
特种医学   1234篇
外国民族医学   14篇
外科学   4529篇
综合类   153篇
一般理论   10篇
预防医学   1753篇
眼科学   563篇
药学   1687篇
中国医学   21篇
肿瘤学   2047篇
  2023年   156篇
  2022年   237篇
  2021年   476篇
  2020年   344篇
  2019年   475篇
  2018年   564篇
  2017年   475篇
  2016年   632篇
  2015年   591篇
  2014年   843篇
  2013年   1101篇
  2012年   1515篇
  2011年   1617篇
  2010年   798篇
  2009年   879篇
  2008年   1499篇
  2007年   1526篇
  2006年   1478篇
  2005年   1462篇
  2004年   1229篇
  2003年   1236篇
  2002年   1147篇
  2001年   980篇
  2000年   978篇
  1999年   853篇
  1998年   399篇
  1997年   305篇
  1996年   255篇
  1995年   248篇
  1994年   211篇
  1993年   201篇
  1992年   510篇
  1991年   536篇
  1990年   518篇
  1989年   429篇
  1988年   402篇
  1987年   418篇
  1986年   419篇
  1985年   405篇
  1984年   293篇
  1983年   238篇
  1981年   163篇
  1979年   275篇
  1978年   196篇
  1977年   165篇
  1976年   159篇
  1975年   173篇
  1974年   201篇
  1973年   181篇
  1972年   167篇
排序方式: 共有10000条查询结果,搜索用时 296 毫秒
1.
2.
ObjectiveSpinal cord stimulation (SCS) is an effective treatment in failed back surgery syndrome (FBSS). We studied the effect of preimplantation opioid use on SCS outcome and the effect of SCS on opioid use during a two-year follow-up period.Materials and methodsThe study cohort included 211 consecutive FBSS patients who underwent an SCS trial from January 1997 to March 2014. Participants were divided into groups, which were as follows: 1) SCS trial only (n = 47), 2) successful SCS (implanted and in use throughout the two-year follow-up period, n = 131), and 3) unsuccessful SCS (implanted but later explanted or revised due to inadequate pain relief, n = 29). Patients who underwent explantation for other reasons (n = 4) were excluded. Opioid purchase data from January 1995 to March 2016 were retrieved from national registries.ResultsHigher preimplantation opioid doses associated with unsuccessful SCS (ROC: AUC = 0.66, p = 0.009), with 35 morphine milligram equivalents (MME)/day as the optimal cutoff value. All opioids were discontinued in 23% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.004). Strong opioids were discontinued in 39% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.04). Mean opioid dose escalated from 18 ± 4 MME/day to 36 ± 6 MME/day with successful SCS and from 22 ± 8 MME/day to 82 ± 21 MME/day with unsuccessful SCS (p < 0.001).ConclusionsHigher preimplantation opioid doses were associated with SCS failure, suggesting the need for opioid tapering before implantation. With continuous SCS therapy and no explantation or revision due to inadequate pain relief, 39% of FBSS patients discontinued strong opioids, and 23% discontinued all opioids. This indicates that SCS should be considered before detrimental dose escalation.  相似文献   
3.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Akteure der öffentlichen Gesundheit (Public Health) tragen wesentlich zu Gesundheitsschutz, -förderung und...  相似文献   
4.
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   
5.
6.
7.
8.
Hawi  N.  von Falck  C.  Krettek  C.  Meller  R. 《Der Unfallchirurg》2019,122(12):944-949
Die Unfallchirurgie - Zur Diagnostik von Schultergelenkerkrankungen wird routinemäßig die Magnetresonanztomographie (MRT) durchgeführt. Diese kann entsprechend der klinischen...  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