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   99766篇
  免费   6941篇
  国内免费   322篇
耳鼻咽喉   1274篇
儿科学   2534篇
妇产科学   2306篇
基础医学   12437篇
口腔科学   2061篇
临床医学   9740篇
内科学   21742篇
皮肤病学   1065篇
神经病学   8652篇
特种医学   3357篇
外国民族医学   3篇
外科学   16223篇
综合类   1401篇
现状与发展   1篇
一般理论   75篇
预防医学   7883篇
眼科学   2649篇
药学   6340篇
中国医学   142篇
肿瘤学   7144篇
  2023年   401篇
  2022年   692篇
  2021年   1646篇
  2020年   880篇
  2019年   1586篇
  2018年   1903篇
  2017年   1399篇
  2016年   1552篇
  2015年   1834篇
  2014年   2726篇
  2013年   4318篇
  2012年   6185篇
  2011年   6454篇
  2010年   3618篇
  2009年   3343篇
  2008年   6123篇
  2007年   6815篇
  2006年   6512篇
  2005年   6661篇
  2004年   6495篇
  2003年   6113篇
  2002年   6103篇
  2001年   782篇
  2000年   538篇
  1999年   764篇
  1998年   1281篇
  1997年   1137篇
  1996年   960篇
  1995年   964篇
  1994年   844篇
  1993年   741篇
  1992年   562篇
  1991年   510篇
  1990年   445篇
  1989年   461篇
  1988年   433篇
  1987年   449篇
  1986年   443篇
  1985年   496篇
  1984年   706篇
  1983年   754篇
  1982年   977篇
  1981年   915篇
  1980年   866篇
  1979年   447篇
  1978年   529篇
  1977年   579篇
  1976年   490篇
  1975年   428篇
  1974年   339篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
122.
Digital nerve injuries in the hand are common and can result in significant impairment and functional restriction. Despite this, there is relatively little literature, particularly with respect to postoperative rehabilitation. Splinting after repair, purported to protect the repaired nerve from excessive stretch is still commonly used. Recent cadaveric studies indicate postoperative rehabilitation is not necessary with resection up to 2.5mm. A randomized controlled trial was therefore undertaken to determine whether splinting after isolated 5th degree digital nerve transection is in fact necessary. Twenty-six subjects were recruited over a two-year period and randomized to either three weeks of hand-based splinting or free active motion. ANCOVA indicated no differences in sensibility at six months between the two groups. Subjects also reported their greatest functional limitations were because of hyperesthesia. Although this study is underpowered, these limited results suggest splinting may not be required postoperatively.  相似文献   
123.
124.
125.
126.
127.
Presented in this report is a modified arthroscopic approach to acromioclavicular joint reconstruction via suture and allograft fixation. An arthroscopic approach is used to expose the base of the coracoid by use of electrocautery. After an open distal clavicle excision is performed, clavicular and coracoid tunnels are created under arthroscopic visualization as previously described by Wolf and Pennington. The myotendinous end of a semitendinosus allograft is sutured to a Spider plate (Kinetikos Medical, San Diego, CA). The tendinous end of the graft is prepared with a running baseball stitch. A Nitinol wire with a loop end (Arthrex, Naples, FL) is used to pass 2 free FiberTape sutures (Arthrex) and the leading sutures from the tendinous end of the graft through the clavicular and coracoid tunnels, exiting out the anterior portal. One of the FiberTape sutures is retrieved with a grasper and passed over the anterior aspect of the distal clavicle. The second FiberTape suture and the allograft are passed over the distal end of the resected clavicle. While the acromioclavicular joint is held reduced, the FiberTape sutures are tied to the plate and the allograft is tensioned medially until the plate is embedded against the superior surface of the clavicle. The tendinous end of the graft is secured to the superior surface of the clavicle with a Bio-tenodesis screw (Arthrex) medial to the clavicular tunnel.  相似文献   
128.
The impact of clinical risk factor-based absolute risk methods on the prevalence of high risk for osteoporotic fracture is unknown. We applied absolute risk methods to 6646 subjects and found that the prevalence of elderly women deemed to be at high risk increased substantially, whereas the overall prevalence was highly dependent on the threshold used to designate high risk. INTRODUCTION: Many groups have advocated using absolute risk methods that incorporate clinical risk factors to target patients for osteoporosis therapy. We examined how the application of such absolute risk classification systems influences the prevalence of those considered to be at high risk for osteoporotic fracture and compared these systems to one based solely on BMD. MATERIALS AND METHODS: Using 6646 subjects from the Canadian Multicentre Osteoporosis Study (CaMos), a prospective, randomly selected, population-based cohort, we assessed three different systems for determining prevalence of high risk for osteoporotic fracture: a BMD-based system; a simplified risk factor system incorporating age, sex, BMD, and two clinical risk factors; and a comprehensive system, incorporating age, sex, BMD, and seven clinical risk factors. The 10-year absolute risks of incident fragility fracture were compared across systems using three different high-risk thresholds. RESULTS: The prevalence of a T score < or = -2.5 was 18.8% (95% CI: 17.7-19.9%) in women and 3.9% (95% CI: 3.0-4.7%) in men. Using a 15% 10-year risk of fracture threshold, the prevalence of women at high risk increased to 46.9% (95% CI: 45.4-48.4) and 42.5% (95% CI: 41.1-43.9) when the comprehensive and simplified risk factor classification systems were used, respectively. Using a 25% 10-year absolute risk threshold, the prevalence of high risk was similar to that of the BMD-based system, whereas the 20% threshold gave intermediate rates. All thresholds analyzed resulted in an increased prevalence of older women at high risk for fracture, whereas only the 15% 10-year risk of fracture threshold resulted in an increase in the prevalence of men at high risk. CONCLUSIONS: The application of risk factor-based systems results in an increased prevalence of older women at high risk. The prevalence of individuals at high risk may increase with changes to the methods used to determine those who are eligible for therapy. These data have important implications for the pattern of care and costs of treating osteoporotic fractures.  相似文献   
129.
130.
We report the first case in the world literature of a patient with an atrial septal defect, severe pulmonary hypertension, and equalization of pulmonary and systemic pressures, who underwent successful closure of an ASD following prolonged therapy with the intravenous vasodilator epoprostenol. Judicious use of continuous prostacyclin in apparently inoperable patients with congenital heart disease may be associated with significant reversal of pulmonary hypertension, and conversion to an operable state.  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