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   2445351篇
  免费   175634篇
  国内免费   4802篇
耳鼻咽喉   33021篇
儿科学   80099篇
妇产科学   67024篇
基础医学   348858篇
口腔科学   70919篇
临床医学   221287篇
内科学   469658篇
皮肤病学   55738篇
神经病学   189607篇
特种医学   93427篇
外国民族医学   437篇
外科学   369676篇
综合类   53884篇
现状与发展   5篇
一般理论   757篇
预防医学   179956篇
眼科学   57936篇
药学   184972篇
  13篇
中国医学   6179篇
肿瘤学   142334篇
  2021年   18321篇
  2019年   18987篇
  2018年   27544篇
  2017年   21164篇
  2016年   23517篇
  2015年   26613篇
  2014年   36733篇
  2013年   53801篇
  2012年   74159篇
  2011年   78176篇
  2010年   46356篇
  2009年   43317篇
  2008年   72423篇
  2007年   77304篇
  2006年   77948篇
  2005年   74509篇
  2004年   71668篇
  2003年   68465篇
  2002年   65922篇
  2001年   127897篇
  2000年   130911篇
  1999年   108556篇
  1998年   28404篇
  1997年   24848篇
  1996年   24936篇
  1995年   23822篇
  1994年   21751篇
  1993年   20323篇
  1992年   81999篇
  1991年   79089篇
  1990年   76864篇
  1989年   73779篇
  1988年   67073篇
  1987年   65345篇
  1986年   61763篇
  1985年   58538篇
  1984年   42860篇
  1983年   36489篇
  1982年   20496篇
  1979年   38169篇
  1978年   26243篇
  1977年   22833篇
  1976年   20714篇
  1975年   22525篇
  1974年   26917篇
  1973年   25942篇
  1972年   24220篇
  1971年   22610篇
  1970年   20911篇
  1969年   19776篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
32.
33.
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   
34.
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   
35.
36.
37.
38.
39.
We report a Chinese family with members affected by epidermolytic ichthyosis (EI), caused by KRT gene mutations. The proband was a 14‐year‐old boy who had simultaneous appearance of nephroblastoma and epidermolytic ichthyosis (EI). Both the patient and his mother exhibited the specific clinical and pathological manifestations of EI. We analysed all exons and flanking sequences of the KRT1 and KRT10 genes using PCR, and found that the proband and his mother had a G>C transition at nucleotide position 1432 in exon 7 of KRT1, resulting in an amino acid substitution of glutamate (GAA) to glutamine (CAA) at codon 478 (E478Q). The KRT10 gene had no mutations.  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