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   710828篇
  免费   49160篇
  国内免费   1319篇
耳鼻咽喉   9210篇
儿科学   23562篇
妇产科学   17669篇
基础医学   110943篇
口腔科学   20060篇
临床医学   64243篇
内科学   135403篇
皮肤病学   16233篇
神经病学   49863篇
特种医学   25860篇
外国民族医学   76篇
外科学   105391篇
综合类   14937篇
现状与发展   2篇
一般理论   163篇
预防医学   51640篇
眼科学   16456篇
药学   54223篇
  3篇
中国医学   2373篇
肿瘤学   42997篇
  2021年   5602篇
  2018年   8034篇
  2017年   6222篇
  2016年   6961篇
  2015年   7685篇
  2014年   10475篇
  2013年   15597篇
  2012年   20865篇
  2011年   21900篇
  2010年   12926篇
  2009年   12127篇
  2008年   20286篇
  2007年   21783篇
  2006年   22172篇
  2005年   20671篇
  2004年   20216篇
  2003年   19172篇
  2002年   18642篇
  2001年   36412篇
  2000年   36983篇
  1999年   30454篇
  1998年   7916篇
  1997年   6690篇
  1996年   6994篇
  1995年   6646篇
  1994年   6119篇
  1993年   5610篇
  1992年   23003篇
  1991年   22959篇
  1990年   22339篇
  1989年   22106篇
  1988年   20068篇
  1987年   19434篇
  1986年   18488篇
  1985年   17338篇
  1984年   12721篇
  1983年   10764篇
  1982年   5938篇
  1979年   11537篇
  1978年   8143篇
  1977年   6843篇
  1976年   6602篇
  1975年   7273篇
  1974年   8508篇
  1973年   8146篇
  1972年   7666篇
  1971年   7138篇
  1970年   6881篇
  1969年   6310篇
  1968年   5784篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
The incidence of asthma has been reported to be associated with obesity. An alternative analysis, of net change in prevalence, does not require exclusion of those with asthma at baseline. Follow-up data were obtained from 9,552 participants in the European Community Respiratory Health Survey and the Swiss cohort Study on Air Pollution and Lung Disease in Adults. Incidence of asthma was analysed by proportional hazards regression, and net changes in symptoms and asthma status by generalised estimating equations, by obesity group. Incidence and net change in ever having had asthma were greater in females than in males, and in participants who remained obese compared with those who were never obese (hazard ratio 2.00, 95% confidence interval 1.25-3.20; excess net change 2.8%, 0.4-5.3% per 10 yrs). The effect of being obese on net change in diagnosed asthma was greater in females than in males, but for net change in wheeze without a cold it was greater in males. The present results are consistent with asthma being more frequently diagnosed in females, especially obese females. These findings may help to explain the reports of a stronger association between asthma and obesity in females than in males.  相似文献   
32.
33.
34.
BACKGROUND: Arterial hypertension and postmenopausal reduction of estrogen levels may be involved in modifications of the stiffness of large arteries. OBJECTIVES: To evaluate the pulse-wave velocity (PWV) and indirectly the arterial stiffness in hypertensive postmenopausal women submitted to hormone therapy with estradiol alone or combined with norethisterone acetate. SUBJECTS: Forty-five hypertensive postmenopausal women were double-blindly, randomly assigned to three arms of treatment: placebo (group I); estradiol 2 mg/day (group II); or estradiol 2 mg/day and norethisterone acetate 1 mg/day (group III). METHODS: Arterial stiffness was assessed from PWV measurements of the common carotid and femoral arteries (CF-PWV) and the common carotid and radial arteries (CR-PWV) obtained using the automatic Complior(R) device, taken at baseline and after 12 weeks of treatment. RESULTS: After the 12-week treatment, values of CF-PWV and CR-PWV were not significantly different (p = 0.910 and p = 0.736, respectively) among the groups. Systolic blood pressure showed a positive correlation with CF-PWV in groups II and III (p = 0.02 and p < 0.001, respectively). CONCLUSIONS: PWV and arterial stiffness in postmenopausal hypertensive women did not reduce over a 12-week treatment with estradiol alone compared with the same period of treatment with estradiol combined with norethisterone acetate.  相似文献   
35.
36.
A true comparison of long-term medical and surgical treatment in gastro-oesophageal reflux disease (GORD) is impossible as few studies have been carried out with adequate randomisation of the patients and long-term evaluation of quality of life. In general the control of the reflux symptoms is roughly equal with medical and surgical treatment. However, surgery can cause other symptoms such as dysphagia or non-specific epigastric discomfort or pain in some patients, which reduces the overall efficacy in controlling the symptoms. Based on a cost utility analysis, Heudebert et al. came to the conclusion that medical treatment was their preferred strategy for most patients with severe erosive oesophagitis.  相似文献   
37.
38.
39.
Acute renal failure (ARF) developed in a 7-week-old infant due to bilateral candidal bezoars (fungal balls) causing obstruction at the pelviureteric junction. The baby was born at term with an appropriate birthweight, and had been treated with broad-spectrum antibiotics for respiratory distress and septicemia during the 1st week of life. Recovery from ARF followed renal decompression with bilateral nephrostomy tube placement and parenteral administration of amphotericin B and 5-flucytosine. Received August 21, 1996; received in revised form and accepted January 3, 1997  相似文献   
40.
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