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   1704209篇
  免费   123620篇
  国内免费   3825篇
耳鼻咽喉   21846篇
儿科学   55764篇
妇产科学   46218篇
基础医学   242207篇
口腔科学   48877篇
临床医学   151797篇
内科学   335530篇
皮肤病学   38806篇
神经病学   131910篇
特种医学   64301篇
外国民族医学   242篇
外科学   258497篇
综合类   38967篇
现状与发展   4篇
一般理论   531篇
预防医学   124431篇
眼科学   40597篇
药学   124238篇
  7篇
中国医学   4485篇
肿瘤学   102399篇
  2021年   12902篇
  2019年   13609篇
  2018年   20101篇
  2017年   15331篇
  2016年   16789篇
  2015年   19118篇
  2014年   26441篇
  2013年   38240篇
  2012年   53186篇
  2011年   55929篇
  2010年   33068篇
  2009年   30961篇
  2008年   52062篇
  2007年   55402篇
  2006年   55883篇
  2005年   53172篇
  2004年   51362篇
  2003年   48707篇
  2002年   46984篇
  2001年   91880篇
  2000年   93689篇
  1999年   77073篇
  1998年   19857篇
  1997年   17419篇
  1996年   17507篇
  1995年   16849篇
  1994年   15392篇
  1993年   14170篇
  1992年   57441篇
  1991年   55318篇
  1990年   53019篇
  1989年   50787篇
  1988年   46172篇
  1987年   44967篇
  1986年   42265篇
  1985年   40023篇
  1984年   29389篇
  1983年   24945篇
  1982年   13935篇
  1979年   25554篇
  1978年   17592篇
  1977年   14937篇
  1976年   13895篇
  1975年   14576篇
  1974年   17640篇
  1973年   16954篇
  1972年   15681篇
  1971年   14458篇
  1970年   13434篇
  1969年   12527篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
BACKGROUND Approximately 20% of patients with neuroendocrine tumours(NETs) develop carcinoid syndrome(CS),characterised by flushing and diarrhoea.Somatostatin analogues or telotristat can be used to control symptoms of CS through inhibition of serotonin secretion.Although CS is often the cause of diarrhoea among patients with gastroenteropancreatic NETs(GEP-NETs),other causes to consider include pancreatic enzyme insufficiency(PEI),bile acid malabsorption and small intestinal bacterial overgrowth.If other causes of diarrhoea unrelated to serotonin secretion are mistaken for CS diarrhoea,these treatments may be ineffective against the diarrhoea,risking detrimental effects to patient quality of life.AIM To identify and synthesise qualitative and quantitative evidence relating to the differential diagnosis of diarrhoea in patients with GEP-NETs.METHODS Electronic databases(MEDLINE,Embase and the Cochrane Library) were searched from inception to September 12,2018 using terms for NETs and diarrhoea.Congresses,systematic literature review bibliographies and included articles were also hand-searched.Any study designs and publication types were eligible for inclusion if relevant data on a cause(s) of diarrhoea in patients with GEP-NETs were reported.Studies were screened by two independent reviewers at abstract and full-text stages.Framework synthesis was adapted to synthesise quantitative and qualitative data.The definition of qualitative data was expanded to include all textual data in any section of relevant publications.RESULTS Forty-seven publications(44 studies) were included,comprising a variety of publication types,including observational studies,reviews,guidelines,case reports,interventional studies,and opinion pieces.Most reported on PEI on/after treatment with somatostatin analogs;9.5%-84% of patients with GEP-NETs had experienced steatorrhoea or confirmed PEI.Where reported,14.3%–50.7% of patients received pancreatic enzyme replacement therapy.Other causes of diarrhoea reported in patients with GEP-NETs included bile acid malabsorption(80%),small intestinal bacterial overgrowth(23.6%-62%),colitis(20%) and infection(7.1%).Diagnostic approaches included faecal elastase,breath tests,tauroselcholic(selenium-75) acid(Se HCAT) scan and stool culture,although evidence on the effectiveness or diagnostic accuracy of these approaches was limited.Assessment of patient history or diarrhoea characteristics was also reported as initial approaches for investigation.From the identified evidence,if diarrhoea is assumed to be CS diarrhoea,consequences include uncontrolled diarrhoea,malnutrition,and perceived ineffectiveness of CS treatment.Approaches for facilitating differential diagnosis of diarrhoea include improving patient and clinician awareness of non-CS causes and involvement of a multidisciplinary clinical team,including gastroenterologists.CONCLUSION Diarrhoea in GEP-NETs can be multifactorial with misdiagnosis leading to delayed patient recovery and inefficient resource use.This systematic literature review highlights gaps for further research on prevalence of non-CS diarrhoea and suitability of diagnostic approaches,to determine an effective algorithm for differential diagnosis of GEP-NET diarrhoea.  相似文献   
12.
Pharmaceutical Chemistry Journal - An HPLC-MS method for simultaneous quantitative determination of a novel gestagenic pharmaceutical and two of its metabolites in rat and rabbit blood sera was...  相似文献   
13.
14.
15.
16.
17.
Dosage form is a mean used for the delivery of drug to a living body. In order to get the desired effect the drug should be delivered to its site of action at such rate and concentration to achieve the maximum therapeutic effect and minimum adverse effect. Since oral route is still widely accepted route but having a common drawback of difficulty in swallowing of tablets and capsules. Therefore a lot of research has been done on novel drug delivery systems. This review is about oral dispersible tablets a novel approach in drug delivery systems that are now a day''s more focused in formulation world, and laid a new path that, helped the patients to build their compliance level with the therapy, also reduced the cost and ease the administration especially in case of pediatrics and geriatrics. Quick absorption, rapid onset of action and reduction in drug loss properties are the basic advantages of this dosage form.  相似文献   
18.
Sinus venosus atrial septal defect (SV‐ASD) usually coexists with partial anomalous pulmonary vein connection (PAPVC). It is a difficult diagnosis in transthoracic echocardiography (TTE) due to eccentric position of defects. We present a rare case of atypical anatomical variation in PAPVC, which was never described before. Two right pulmonary veins drained into superior vena cava, which overrode SV‐ASD and interatrial septum, a third pulmonary vein into the right atrium. Complete diagnosis could not be set after TTE, nor transesophageal echocardiography, whereas angio‐CT was finally conclusive. This diagnostic approach allowed the surgical planning.  相似文献   
19.
20.
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