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   2248篇
  免费   209篇
  国内免费   40篇
耳鼻咽喉   40篇
儿科学   54篇
妇产科学   46篇
基础医学   311篇
口腔科学   52篇
临床医学   206篇
内科学   446篇
皮肤病学   57篇
神经病学   103篇
特种医学   74篇
外科学   347篇
综合类   154篇
预防医学   125篇
眼科学   75篇
药学   193篇
  1篇
中国医学   34篇
肿瘤学   179篇
  2023年   27篇
  2022年   39篇
  2021年   97篇
  2020年   60篇
  2019年   80篇
  2018年   78篇
  2017年   86篇
  2016年   81篇
  2015年   111篇
  2014年   131篇
  2013年   114篇
  2012年   170篇
  2011年   160篇
  2010年   90篇
  2009年   106篇
  2008年   134篇
  2007年   120篇
  2006年   144篇
  2005年   120篇
  2004年   114篇
  2003年   89篇
  2002年   88篇
  2001年   27篇
  2000年   39篇
  1999年   27篇
  1998年   11篇
  1997年   15篇
  1996年   4篇
  1995年   5篇
  1994年   6篇
  1993年   9篇
  1992年   11篇
  1991年   14篇
  1990年   5篇
  1989年   5篇
  1987年   7篇
  1986年   7篇
  1985年   3篇
  1984年   6篇
  1981年   3篇
  1980年   6篇
  1979年   3篇
  1978年   4篇
  1977年   4篇
  1974年   3篇
  1971年   4篇
  1970年   5篇
  1969年   4篇
  1967年   3篇
  1966年   5篇
排序方式: 共有2497条查询结果,搜索用时 15 毫秒
1.
2.
INTRODUCTIONPsoriasis is a chronic inflammatory condition that affects the skin and joints, and is associated with cardiovascular risk factors, including metabolic syndrome (MetS). We aimed to assess the prevalence of MetS in patients with psoriasis and determine whether there was a correlation between psoriasis severity and MetS in a Singapore population.METHODSThis was a cross-sectional study of patients with psoriasis, aged 18–69 years, who attended a tertiary dermatology referral centre in Singapore from October 2007 to February 2009. Fasting glucose, lipids, blood pressure, Psoriasis Area and Severity Index, and body mass index were measured. MetS was diagnosed in the presence of three or more criteria of the modified National Cholesterol Education Program Adult Treatment Panel III.RESULTSAmong 338 patients with psoriasis, there were 238 (70.4%) men and 100 (29.6%) women, who were Chinese (n = 228; 67.5%), Malay (n = 52; 15.4%) and Indian (n = 58; 17.2%). The prevalence of MetS was 45.1%. MetS was 44% more prevalent in patients older than 50 years (p = 0.02). Malay patients with psoriasis were significantly more likely to have hypertriglyceridaemia, elevated fasting plasma glucose and abdominal obesity. There was no significant correlation between psoriasis severity and risk of MetS.CONCLUSIONThe prevalence of MetS in patients with psoriasis in Singapore was 45.1%, or nearly threefold higher than the Singapore general population. Patients with psoriasis should be screened yearly for MetS and any modifiable cardiovascular risk factors should be actively controlled.  相似文献   
3.
4.
5.
6.
7.
This paper considers a dynamic pricing problem over a finite horizon where demand for a product is a time‐varying linear function of price. It is assumed that at the start of the horizon there is a fixed amount of the product available. The decision problem is to determine the optimal price at each time period in order to maximize the total revenue generated from the sale of the product. In order to obtain structural results we formulate the decision problem as an optimal control problem and solve it using Pontryagin's principle. For those problems which are not easily solvable when formulated as an optimal control problem, we present a simple convergent algorithm based on Pontryagin's principle that involves solving a sequence of very small quadratic programming (QP) problems. We also consider the case where the initial inventory of the product is a decision variable. We then analyse the two‐product version of the problem where the linear demand functions are defined in the sense of Bertrand and we again solve the problem using Pontryagin's principle. A special case of the optimal control problem is solved by transforming it into a linear complementarity problem. For the two‐product problem we again present a simple algorithm that involves solving a sequence of small QP problems and also consider the case where the initial inventory levels are decision variables. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
8.

Background  

Acromioclavicular injuries are common in sports medicine. Surgical intervention is generally advocated for chronic instability of Rockwood grade III and more severe injuries. Various methods of coracoclavicular ligament reconstruction and augmentation have been described. The objective of this study is to compare the biomechanical properties of a novel palmaris-longus tendon reconstruction with those of the native AC+CC ligaments, the modified Weaver-Dunn reconstruction, the ACJ capsuloligamentous complex repair, screw and clavicle hook plate augmentation.  相似文献   
9.
10.
Although the conventional outside-in technique is especially useful for repairing tears in the anterior portion of the meniscus, it has a disadvantage of making an additional 1–2 cm sized skin incision and tying knots subcutaneously over the capsule. Therefore we devised two all-inside repair techniques of lateral meniscus anterior horn tear according to the site of meniscal tear, meniscosynovial junction or red–red zone. Because these techniques are modified methods of the outside-in meniscal repair using a spinal needle, they are as simple as conventional outside-in technique. In addition they have advantages of vertical mattress suture, which is an important characteristic of the all-inside repair, and no additional incision. We recommend these techniques as an alternative method for repairing an anterior horn tear of the lateral meniscus.  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