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   3614篇
  免费   232篇
  国内免费   7篇
耳鼻咽喉   131篇
儿科学   112篇
妇产科学   95篇
基础医学   494篇
口腔科学   86篇
临床医学   276篇
内科学   655篇
皮肤病学   167篇
神经病学   273篇
特种医学   410篇
外科学   562篇
综合类   25篇
预防医学   178篇
眼科学   19篇
药学   238篇
中国医学   1篇
肿瘤学   131篇
  2023年   25篇
  2021年   51篇
  2020年   40篇
  2019年   53篇
  2018年   62篇
  2017年   67篇
  2016年   59篇
  2015年   66篇
  2014年   82篇
  2013年   112篇
  2012年   117篇
  2011年   154篇
  2010年   78篇
  2009年   84篇
  2008年   115篇
  2007年   147篇
  2006年   160篇
  2005年   154篇
  2004年   128篇
  2003年   123篇
  2002年   90篇
  2001年   83篇
  2000年   99篇
  1999年   100篇
  1998年   62篇
  1997年   55篇
  1996年   62篇
  1995年   68篇
  1994年   48篇
  1993年   46篇
  1992年   60篇
  1991年   76篇
  1990年   76篇
  1989年   69篇
  1988年   74篇
  1987年   95篇
  1986年   88篇
  1985年   81篇
  1984年   60篇
  1983年   57篇
  1982年   43篇
  1981年   36篇
  1980年   37篇
  1979年   45篇
  1978年   37篇
  1977年   31篇
  1976年   45篇
  1975年   33篇
  1974年   29篇
  1973年   28篇
排序方式: 共有3853条查询结果,搜索用时 15 毫秒
1.
2.
2000年11月,作者得知从Aarhus大学医院皮肤科患者分离到的金黄色葡萄球菌对苯唑西林出现界线耐药(BORSA)。本文旨在描述其表型和基因型,并评估可能的传播途径以干预和阻止进一步蔓延。菌株由脉冲场凝胶电泳鉴定。几个感染控制方案的缺口显示患者间可直接或间接传播。皮肤屏障缺陷、皮肤病患者金黄色葡萄球菌的高携带率和院内双氯西林的高消耗率可促使传播。改善普通感染控制措施和重新评价院内抗生素政策后,该菌的暴发感染消失。  相似文献   
3.
Bone turnover before and after withdrawal of estrogen/gestagen treatment was studied in a randomized trial with 110 healthy female volunteers, who had passed a natural menopause 6 months to 3 years before the start of the study. Urinary excretion of intravenously injected 99m-technetium diphosphonate was measured as an index of bone turnover; plasma bone Gla protein and serum alkaline phosphatase were measured as indices of bone formation; and fasting urinary excretion of hydroxyproline and calcium were measured as estimates of bone resorption. During 2 years of hormone treatment, all variables decreased highly significantly (p less than 0.001) to a constant low level. Three months after withdrawal all variables increased highly significantly (p less than 0.001) towards, but not above, pretreatment and placebo levels. We conclude that withdrawal of estrogen/gestagen replacement therapy in postmenopausal women increases bone turnover, but not in excess of pretreatment values. This indicates that bone loss (after withdrawal) is similar to that seen in the placebo group and that a rebound phenomenon is unlikely.  相似文献   
4.
BACKGROUND: Toxic epidermal necrolysis (TEN) is a severe and potentially fatal drug reaction characterized by an extensive skin rash with blisters and exfoliation, frequently accompanied by mucositis. The wounds caused by TEN are similar to second-degree burns and severe cases may involve large areas of skin loss. OBJECTIVES: Analysis of our results in patients with TEN and evaluation of the variety of therapeutic interventions that has been studied and suggested in TEN. PATIENTS/METHODS: Retrospective analysis of 19 consecutive patients with TEN treated in our burns centre between 1989 and 2004. RESULTS: Immediate withdrawal of any potentially fatal drug, maximum supportive care, and a restricted and tailored antibiotic, medical and surgical treatment regimen confined mortality to 21%, whereas prognosis scores like APACHE II and SCORTEN predicted mortality of 22 and 30%, respectively. A positive contribution of selective digestive decontamination is suggested but has yet to be established. CONCLUSIONS: Because of a potentially fatal outcome, fast referral of a patient suspected of TEN to a specialized centre (mostly a burns unit or specialized dermatology centre) for expert wound management and tailored comprehensive care is strongly advised and contributes to survival.  相似文献   
5.
ABSTRACT— One hundred and fifty-four patients with histologically verified nonalcoholic chronic liver disease were randomized to azathioprine or prednisone treatment. After a median of 91 months observation time, the cause of death was assessed retrospectively. Autopsy was performed in 82% of 71 deaths. In the azathioprine group 33% (13/39) died from malignant neoplasia, and in the prednisone group (13%) (4/32) (p = 0.08). Considering a possible fatal outcome as a consequence of treatment, this finding urges caution in the long-term application of azathioprine at the usual dose level.  相似文献   
6.
7.
1背景 育龄妇女常见慢性下腹痛,可造成身体损害、情绪忧伤及导致巨大的健康服务费用。美国在这方面的花费超过8亿8千万美元(Mathias 1996)。英国全国数据库的一般性诊治资料显示,慢性下腹痛发病率及流行率与偏头痛、背部痛、哮喘发病率相似(Zondervan 1999)。  相似文献   
8.
Pyelography is superior to all other imaging techniques for the demonstration of fine detail in the pelveocalyceal system and the ureter. For almost 90 years it has been performed through a retrogradely inserted catheter, but during the recent 30 years antegrade injection via a transparenchymally inserted needle or catheter has become an accepted alternative, especially in case of a dilated upper urinary tract. Both methods have their advantages and their disadvantages. This article presents a review of indications, techniques, and complications. Furthermore, interventional procedures on the upper urinary tract--such as stent placement and balloon dilatation--are now handled by the radiologist, mainly through an antegrade approach. These therapeutic procedures are also reviewed.  相似文献   
9.
10.
BACKGROUND: Season of birth (SOB) has been regarded as a risk factor for atopy. The aim of this study was to explore the relationship between season of birth (SOB) and later development of atopic disease in children and adolescents. METHODS: A total of 1,007 randomly selected subjects, 7 to 17 years of age, who were living in urban Copenhagen, Denmark were studied. All participants were interviewed about respiratory symptoms and possible risk factors for atopic disease. Skin test reactivity, serum total immunoglobulin E (IgE), and airway responsiveness were measured using standard techniques. RESULTS: The overall risk of atopy, as judged by skin test reactivity and serum total IgE, was the same regardless of SOB. On the contrary, asthma was more common in subjects born in the autumn compared with subjects born during the remaining part of the year (12.4% vs. 5.6%), OR = 2.40, 95% CI (1.56-3.94), p < 0.001. This was observed both for atopic asthma OR = 2.41, 95% CI (1.25-4.64), p = 0.007, non-atopic asthma, OR = 2.35, 95% CI (1.14-4.83), p = 0.02, and house dust mite (HDM) sensitive airway hyperresponsiveness, OR = 3.00, 95% CI (1.44-6.24), p = 0.002. Rhinitis and pollen allergy were not significantly related to SOB. CONCLUSIONS: Atopy itself is independent of season of birth, whereas asthma is more prevalent among subjects born during the autumn. Regarding asthma, these results suggest that the first months of life enclose a period of particular vulnerability towards environmental risk factors, especially exposure to aeroallergens like HDM.  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