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   3231869篇
  免费   257579篇
  国内免费   6655篇
耳鼻咽喉   45961篇
儿科学   102127篇
妇产科学   89191篇
基础医学   452757篇
口腔科学   92546篇
临床医学   295510篇
内科学   631740篇
皮肤病学   69025篇
神经病学   271952篇
特种医学   126917篇
外国民族医学   1186篇
外科学   484723篇
综合类   78355篇
现状与发展   4篇
一般理论   1331篇
预防医学   262424篇
眼科学   76488篇
药学   236450篇
  5篇
中国医学   6554篇
肿瘤学   170857篇
  2018年   34565篇
  2017年   26528篇
  2016年   29476篇
  2015年   33302篇
  2014年   47952篇
  2013年   72627篇
  2012年   97966篇
  2011年   103565篇
  2010年   61091篇
  2009年   58471篇
  2008年   97308篇
  2007年   103299篇
  2006年   104314篇
  2005年   101493篇
  2004年   97366篇
  2003年   93665篇
  2002年   91655篇
  2001年   150849篇
  2000年   155576篇
  1999年   131001篇
  1998年   38395篇
  1997年   34790篇
  1996年   34455篇
  1995年   33038篇
  1994年   30725篇
  1993年   28794篇
  1992年   103548篇
  1991年   99547篇
  1990年   95876篇
  1989年   92166篇
  1988年   85478篇
  1987年   84077篇
  1986年   79256篇
  1985年   75734篇
  1984年   57802篇
  1983年   49252篇
  1982年   30172篇
  1981年   26841篇
  1979年   53490篇
  1978年   37753篇
  1977年   31660篇
  1976年   29759篇
  1975年   31006篇
  1974年   38133篇
  1973年   36433篇
  1972年   34184篇
  1971年   31443篇
  1970年   29737篇
  1969年   27670篇
  1968年   25618篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
102.
INTRODUCTION: Autoimmune hepatitis (AIH) is a well-defined entity in the West but there are sparse Indian data on this disease. AIM: To study the clinical profile and response to treatment of Indian patients with AIH. METHODS: This is a part retrospective and part prospective study of 50 patients (median age 48 years, range 11-82; 43 women) seen between 1995 to 2001, diagnosed to have AIH as per the revised scoring system. Clinical and laboratory profile, response to treatment, and complications of treatment were analyzed. RESULTS: AIH accounted for 6% of all patients with liver disease seen during the period. The presenting symptoms were gastrointestinal in 43 and non-gastrointestinal in 7, with median symptom duration of 6 months (range 2 weeks to 40 years). Forty patients (80%) had chronic liver disease. Associated illnesses were present in 28 patients. Twenty-six patients were classified as definite and the rest as probable AIH. Forty-nine patients had Type 1 AIH. Five patients had overlap syndrome. Forty-five patients (90%) received immunosuppressive therapy. Twelve of 18 patients receiving only prednisolone and 21 of 27 patients receiving prednisolone and azathioprine combination responded. Thirteen (26%) patients had therapy-related complications (infectious 5, non infectious 8) with two treatment-related deaths. CONCLUSION: Type 1 AIH was the predominant type of AIH. The majority of patients with AIH presented with chronic liver disease. There was good response to immunosuppressive therapy. Therapy-related complications occurred in one-fourth of patients.  相似文献   
103.
灾难的时代错误:灾害医学的过去、现在和将来(一)   总被引:1,自引:0,他引:1  
灾难,特别是地震、火山、洪水以及与战争有关的事件如饥饿和流行性传染病,是人类有记录的经历的一部分。从意大利庞贝的火山爆发,到约翰斯顿的洪水、第二次世界大战和黑色瘟疫,到西班牙流感,都发生了灾难,这不会被传说和历史书籍长期忘却。不过,在20世纪中叶以前,那些灾难的发生相对较少,且相距时间较长。从20世纪中叶以来,灾难的本质发生了变化。从恐怖分子使用“新技术”,到与气候有关的导致亿万美元经济损失的事件,表明这个世界正在发生变化。仅仅在最近的50~60年间,造成多种多样的伤亡事件,其危险性和频率的增加引人注目,并且注定要在接…  相似文献   
104.
The aim of the present study was to explore differences in the clinical expression, clinical diagnoses and management of airway diseases in a primary-care setting. Patients aged >or=35 yrs who had ever smoked were enrolled when they presented for any reason to one of eight rural primary-care practices. Respiratory symptom questionnaires and spirometry were administered. In total, 1,034 patients had acceptable and reproducible spirometry, of whom 550 (53%) were males and 484 (47%) were females. Males smoked more than females (41.2 versus 29.2 pack-yrs) respectively, and were more likely to have a pre-bronchodilator forced expiratory volume in one second/forced vital capacity <0.70 at 22.4 versus 11.8%, respectively. However, more females than males reported breathlessness (51.0 versus 42.8%, respectively), a prior diagnosis compatible with airflow obstruction and taking respiratory medications (23.4 versus 14.9%, respectively). In conclusion, the current results suggest that females are more likely than males to report breathlessness and be prescribed respiratory medications independent of differences in the severity of airflow obstruction.  相似文献   
105.
106.
A new semi-empirical formula for the evaluation of (n,(3)He) reaction cross-sections at the energy of 14.6 and 20 MeV is presented. Formula was derived using the analytical expression for the evaluation of the (3)He spectrum within the frame of pre-equilibrium exciton model. The systematics obtained is compared with the empirical formula for the (n,(3)He) reaction cross-section.  相似文献   
107.
108.
109.
110.
Liposarcomas are extremely rare in the mediastinum. They may achieve considerable size before causing any symptoms. Mediastinal liposarcomas may invade surrounding structures like the pericardium or the superior vena cava. Complete surgical excision is the optimal treatment in resectable cases. Excision of adjacent structures like the pericardium may be needed if the tumor infiltrates them. We report on a case of a giant liposarcoma of the mediastinum involving both hemithoraces and extending into the neck, which was successfully managed by complete surgical excision.  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