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   98239篇
  免费   11341篇
  国内免费   4839篇
耳鼻咽喉   1020篇
儿科学   1952篇
妇产科学   978篇
基础医学   6393篇
口腔科学   2120篇
临床医学   12829篇
内科学   10991篇
皮肤病学   1290篇
神经病学   3613篇
特种医学   4159篇
外科学   9360篇
综合类   21847篇
现状与发展   13篇
一般理论   18篇
预防医学   12871篇
眼科学   1356篇
药学   9960篇
  119篇
中国医学   8425篇
肿瘤学   5105篇
  2024年   487篇
  2023年   1468篇
  2022年   2878篇
  2021年   3731篇
  2020年   3369篇
  2019年   1916篇
  2018年   2454篇
  2017年   2959篇
  2016年   2473篇
  2015年   4070篇
  2014年   5032篇
  2013年   6562篇
  2012年   8220篇
  2011年   8538篇
  2010年   7671篇
  2009年   6975篇
  2008年   6945篇
  2007年   6679篇
  2006年   5968篇
  2005年   4765篇
  2004年   3552篇
  2003年   2893篇
  2002年   2454篇
  2001年   2134篇
  2000年   1534篇
  1999年   901篇
  1998年   562篇
  1997年   549篇
  1996年   539篇
  1995年   422篇
  1994年   376篇
  1993年   373篇
  1992年   437篇
  1991年   368篇
  1990年   319篇
  1989年   334篇
  1988年   309篇
  1987年   287篇
  1986年   280篇
  1985年   252篇
  1984年   196篇
  1983年   178篇
  1982年   143篇
  1981年   146篇
  1980年   136篇
  1979年   109篇
  1978年   106篇
  1977年   112篇
  1976年   118篇
  1972年   99篇
排序方式: 共有10000条查询结果,搜索用时 6 毫秒
101.
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.  相似文献   
102.
The new complaints procedures which local authority social services departments have been required to introduce represent an important mechanism for managing the change of culture associated with recent community care reforms. They also represent a new genre in mechanisms of redress for welfare recipients. This paper reports the findings of a study which has observed considerable diversity in the ways in which local authorities are interpreting the nature and purposes of the new procedures and, in particular, the functions of review panels established under those procedures. Variations in the composition of panels, in the style of review panel proceedings, in perceptions of the panels' powers, and in the ways that complaints and complainants are constituted are all discussed. Attention is drawn to four competing interpretations of the review panels' role and to the need for these to be clarified and prioritised.  相似文献   
103.
104.
1. Epidermal growth factor is a potent mitogen that causes natriuresis, diuresis and inhibition of arginine vasopressin-induced water reabsorption. 2. The aim of this study was to determine any interaction between epidermal growth factor and the V1 (vascular) and/or V2 (antidiuretic) arginine vasopressin receptor subtypes. 3. Radioligand binding displacement assays demonstrated that although arginine vasopressin related peptides displaced both radioligands from renal medullary membranes at low concentrations epidermal growth factor displaced neither. 4. Arginine vasopressin V2 receptor second messenger cyclic adenosine monophosphate (CAMP) production was inhibited by epidermal growth factor (IC50 2 ± 10?7 mol/L) as was sodium fluoride cAMP production but only at much higher concentrations. 5. Therefore the diuretic effect of epidermal growth factor is not via direct antagonism of arginine vasopressin receptors but seems mediated via inhibition of the V2 second messenger system.  相似文献   
105.
The concept of need and the practice of needs assessment are both subject to a wide range of interpretations, to the likely detriment of individual assessments and to multidisciplinary working. Clear definition is important for individual assessment, for the development of multidisciplinary tools and in gathering planning information. The concept of need is clarified, firstly by distinguishing between need and the difficulties that engender it, and secondly through a taxonomy of need. These assist clear definitions of both need and needs assessment when linked with a consideration of the current help a person receives and a specification of the type of help required by a person to meet their needs. Such definitions have implications for the role of needs assessment in individual assessment, service evaluation, service management and planning and in the development of multidisciplinary needs assessment tools.  相似文献   
106.
Vaginal candidosis is one of the most common infections of the vagina and the first accredited record of the disease appeared in 1849. Over the years the terms ‘candidiasis’ and ‘candidosis’ have been used, but it is generally accepted now that the terms are synonymous, and the term most commonly in use today is ‘candidosis’. Mainly caused by the yeast Candida albicans, the condition is characterised by intense inflammation of the vaginal mucosa and a curdy, off-white discharge; it is often associated with severe vulval itching and possibly burning pain. The severity of symptoms seems to vary greatly from patient to patient and the reason for this is unclear. It is suggested that in some patients there may be an element of hypersensitivity. Vaginal candidosis may occur in children but is most common in adults and only sometimes affects the elderly. The majority of women will suffer at least one attack of vaginal candidosis during their lifetime, and there are several predisposing factors such as diabetes, pregnancy and antibiotics. Some authorities consider the condition more frequent in those taking oral contraceptives or other hormones.  相似文献   
107.
目的 探讨5km重复低压缺氧对小鼠肝脏及脾脏中微量元素的影响。方法 将小白鼠分为5km重复低压缺氧实验组及地面对照组。实验组每天进行5km重复低压缺氧30min,连续7d后,处死小鼠,取肝脏、脾脏烘干至恒重,采用火焰原子吸收法测定锌、铜、铁。结果 5km重复低压缺氧小鼠肝脏中Cu、Fe含量与对照组比较有显差异(P<0.05);脾脏中微量元素Fe的含量与对照组比较有显性差异(P<0.05)。结论 5km重复低压缺氧,使肝脏中Fe、Cu含量降低,脾脏中Fe含量升高。  相似文献   
108.
109.
110.
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