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   287412篇
  免费   21483篇
  国内免费   2717篇
耳鼻咽喉   3128篇
儿科学   7139篇
妇产科学   5131篇
基础医学   36231篇
口腔科学   5257篇
临床医学   29714篇
内科学   58518篇
皮肤病学   3935篇
神经病学   26243篇
特种医学   9421篇
外国民族医学   13篇
外科学   41698篇
综合类   9174篇
现状与发展   17篇
一般理论   340篇
预防医学   25000篇
眼科学   7522篇
药学   21001篇
  62篇
中国医学   2820篇
肿瘤学   19248篇
  2023年   1854篇
  2022年   3812篇
  2021年   7244篇
  2020年   4746篇
  2019年   6475篇
  2018年   7253篇
  2017年   5778篇
  2016年   6121篇
  2015年   7405篇
  2014年   10473篇
  2013年   13827篇
  2012年   21035篇
  2011年   21990篇
  2010年   12839篇
  2009年   11364篇
  2008年   18974篇
  2007年   19634篇
  2006年   19231篇
  2005年   19040篇
  2004年   17455篇
  2003年   16220篇
  2002年   15028篇
  2001年   2485篇
  2000年   1933篇
  1999年   2542篇
  1998年   3307篇
  1997年   2740篇
  1996年   2317篇
  1995年   2207篇
  1994年   1862篇
  1993年   1653篇
  1992年   1352篇
  1991年   1244篇
  1990年   1073篇
  1989年   1027篇
  1988年   1016篇
  1987年   992篇
  1986年   1011篇
  1985年   1009篇
  1984年   1273篇
  1983年   1180篇
  1982年   1424篇
  1981年   1354篇
  1980年   1180篇
  1979年   724篇
  1978年   779篇
  1977年   666篇
  1976年   593篇
  1975年   482篇
  1974年   490篇
排序方式: 共有10000条查询结果,搜索用时 18 毫秒
21.
22.
23.
24.
This study surveyed male and female athletes from 22 midwesterncolleges and universities regarding behaviors and attitudesassociated with anorexia nervosa and bulimia nervosa. The responserate was 66% (N= 695) and the findings indicated that the bodyimage of some athletes may be distorted; one-seventh perceivedthemselves as fat even though they were not. Many athletes seemedpreoccupied with food and weight; almost one-third reportedroutinely thinking about food and weight and more than one-thirdreported dramatic annual weight fluctuations (9 lb or greater)related to bingeing and fasting. Athletes also did not feelin control when they ate and their habits related to food consumptionappeared to be extreme; one-tenth reported a lack of controlwhen they ate, more than one-third binged, one-twentieth ateuntil they were physically ill, and a similar proportion preferrednot to eat in the presence of others. In addition, it was foundthat as many men as women athletes reported these perceptionsbut significant sex differences were noted for specific items.It was suggested that behaviors and attitudes be viewed on acontinuum with normals at one end, eating disordered individuals at the other end,and college athletes in between. Health education that focuseson behaviors and attitudes as symptoms of eating disorders wasrecommended for athletes and those working closely with athletes.Future research was suggested to determine reasons for the undesirablebehaviors and attitudes and to study the onset, development,long-term effects and whether these behaviors and attitudeslead to an eating disorder.  相似文献   
25.
Abstract This paper examines the impact of medical technology on the careers of people with post-polio respiratory disability. The data have been taken from multiple in-depth interviews with ten people who contracted polio during the epidemics of the early 1950s, all of whom used or had used a variety of methods of mechanical respiratory support. It focuses on ideologies of disability and the adoption of technology, the management of respiratory insufficiency and strategies of'trading off whereby the benefits of technology are maximized and the costs minimized. While technology made an enormous contribution to the quality of life of these people, the problems it created transformed both their experience of the illness and the character of their everyday existence.  相似文献   
26.
27.
Summary: This is the first report of the largest study of blood pressure measurement in pregnancy in a New Zealand population using standardized definitions and methodology. Over 3,800 women who delivered in an 8-month period in the Wellington region were included in the study. Blood pressure measurement and the presence of oedema and proteinuria were recorded from booking until delivery and in the puerperium. Only 2.7% of women were unable to be contacted after delivery for details on outcomes. The results established normal ranges for blood pressure throughout pregnancy. The data show that Mood pressure greater than 140/90 until 35 weeks' gestation is outside 2 standard deviations at all gestations and justifies using these measurements as the definition of hypertension in pregnancy. The fall in blood pressure in the 2nd trimester was less than 1 mm Ffg per week in both the systolic and diastolic pressures. This fall was smaller than previously recorded in other studies. Gestational hypertension was the commonest blood pressure abnormality occurring in 15.2% of the population. This represented 69% of the pregnant women with a hypertensive disorder. The overall incidence of both gestational hypertension and preeclampsia was 18.5% which is higher than reported in other parts of the world. In this study obesity was significantly associated with hypertensive disorders in pregnancy. An arm circumference of >33 cm, one of the measurements of obesity, was found in 6.8% of the study population. Even after the effect of arm circumference was taken into account, hypertensive disorders were also more common in Pacific Island women. Ankle oedema was significantly associated with the development of both gestational hypertension and preeclampsia but the incidence of oedema was noted in only 11.9% of the subjects.  相似文献   
28.
. Neutrophil-mediated tissue damage has been implicated in the pathogenesis of diarrhoea-associated haemolytic uraemic syndrome (D+ HUS). This study evaluates priming and activation of the neutrophil oxidative burst in D+ HUS using chemiluminescent techniques. Peripheral blood neutrophils from 11 children with acute D+ HUS were examined. No difference was found in the oxidative burst of neutrophils from patients and controls. Serum elastase levels were measured in 8 patients and found to be significantly elevated. Although elastase results suggest neutrophil activation, chemiluminescence studies do not confirm this in the peripheral blood neutrophil. This does not support a significant role for circulating agents in priming and activating the peripheral blood neutrophil. Received August 17, 1995; received in revised form and accepted November 27, 1995  相似文献   
29.
30.
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