全文获取类型
收费全文 | 82771篇 |
免费 | 5430篇 |
国内免费 | 284篇 |
专业分类
耳鼻咽喉 | 797篇 |
儿科学 | 2295篇 |
妇产科学 | 1901篇 |
基础医学 | 12110篇 |
口腔科学 | 1358篇 |
临床医学 | 8230篇 |
内科学 | 16491篇 |
皮肤病学 | 1518篇 |
神经病学 | 9419篇 |
特种医学 | 2869篇 |
外国民族医学 | 55篇 |
外科学 | 9229篇 |
综合类 | 785篇 |
一般理论 | 69篇 |
预防医学 | 8133篇 |
眼科学 | 1606篇 |
药学 | 5426篇 |
中国医学 | 129篇 |
肿瘤学 | 6065篇 |
出版年
2023年 | 754篇 |
2022年 | 1316篇 |
2021年 | 2600篇 |
2020年 | 1586篇 |
2019年 | 2215篇 |
2018年 | 2554篇 |
2017年 | 1804篇 |
2016年 | 2008篇 |
2015年 | 2314篇 |
2014年 | 2912篇 |
2013年 | 3955篇 |
2012年 | 6086篇 |
2011年 | 6112篇 |
2010年 | 3228篇 |
2009年 | 2873篇 |
2008年 | 4796篇 |
2007年 | 4882篇 |
2006年 | 4699篇 |
2005年 | 4532篇 |
2004年 | 4128篇 |
2003年 | 3784篇 |
2002年 | 3460篇 |
2001年 | 746篇 |
2000年 | 650篇 |
1999年 | 703篇 |
1998年 | 764篇 |
1997年 | 633篇 |
1996年 | 543篇 |
1995年 | 493篇 |
1994年 | 399篇 |
1993年 | 378篇 |
1992年 | 390篇 |
1991年 | 375篇 |
1990年 | 326篇 |
1989年 | 320篇 |
1988年 | 294篇 |
1987年 | 291篇 |
1986年 | 270篇 |
1985年 | 262篇 |
1984年 | 317篇 |
1983年 | 282篇 |
1982年 | 315篇 |
1981年 | 296篇 |
1980年 | 254篇 |
1979年 | 234篇 |
1978年 | 218篇 |
1976年 | 204篇 |
1975年 | 175篇 |
1974年 | 208篇 |
1973年 | 188篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Mohid S Khan Thomas Walter Amy Buchanan-Hughes Emma Worthington Lucie Keeber Marion Feuilly Enrique Grande 《World journal of gastroenterology : WJG》2020,26(30):4537-4556
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
2.
A case of Rubinstein‐Taybi syndrome associated with growth hormone deficiency in childhood 下载免费PDF全文
3.
4.
5.
Edward J. Holland Walter O. Whitley Kenneth Sall Stephen S. Lane Aparna Raychaudhuri Steven Y. Zhang 《Current medical research and opinion》2016,32(10):1759-1765
Objective: Report efficacy findings from three clinical trials (one phase 2 and two phase 3 [OPUS-1, OPUS-2]) of lifitegrast ophthalmic solution 5.0% for treatment of dry eye disease (DED).Research design and methods: Three 84-day, randomized, double-masked, placebo-controlled trials. Adults (≥18 years) with DED were randomized (1:1) to lifitegrast 5.0% or matching placebo. Changes from baseline to day 84 in signs and symptoms of DED were analyzed.Main outcome measures: Phase 2, pre-specified endpoint: inferior corneal staining score (ICSS; 0–4); OPUS-1, coprimary endpoints: ICSS and visual-related function subscale (0–4 scale); OPUS-2, coprimary endpoints: ICSS and eye dryness score (EDS, VAS; 0–100).Results: Fifty-eight participants were randomized to lifitegrast 5.0% and 58 to placebo in the phase 2 trial; 293 to lifitegrast and 295 to placebo in OPUS-1; 358 to lifitegrast and 360 to placebo in OPUS-2. In participants with mild-to-moderate baseline DED symptomatology, lifitegrast improved ICSS versus placebo in the phase 2 study (treatment effect, 0.35; 95% CI, 0.05–0.65; p?=?0.0209) and OPUS-1 (effect, 0.24; 95% CI, 0.10–0.38; p?=?0.0007). Among more symptomatic participants (baseline EDS ≥40, recent artificial tear use), lifitegrast improved EDS versus placebo in a post hoc analysis of OPUS-1 (effect, 13.34; 95% CI, 2.35–24.33; nominal p?=?0.0178) and in OPUS-2 (effect, 12.61; 95% CI, 8.51–16.70; p?<?0.0001).Limitations: Trials were conducted over 12 weeks; efficacy beyond this period was not assessed.Conclusions: Across three trials, lifitegrast improved ICSS in participants with mild-to-moderate baseline symptomatology in two studies, and EDS in participants with moderate-to-severe baseline symptomatology in two studies. Based on the overall findings from these trials, lifitegrast shows promise as a new treatment option for signs and symptoms of DED. 相似文献
6.
Feasibility and Diagnostic Potential of Pulmonary Transit Time Measurement by Contrast Echocardiography: A Pilot Study 下载免费PDF全文
7.
Elizabeth M. Broad Laura J. Newsome Dustin A. Dew 《The journal of spinal cord medicine》2020,43(3):388-397
Objective: Report measured resting energy expenditure (REE) in wheelchair rugby athletes and evaluate agreement between REE and the prediction models of Chun, Cunningham, Harris-Benedict, Mifflin, Nightingale and Gorgey, and Owen.Design: Cohort-based validation study.Setting. Paralympic team training camp.Participants: Fourteen internationally competitive athletes who play wheelchair rugby, 13 of whom had cervical spinal cord injuries (SCI).Outcome Measures: A portable metabolic analyzer was used to measure REE following an overnight fast and dual-energy X-ray absorptiometry (DXA) was used to assess lean body mass for the prediction equations.Results: REE in the current sample was 1735?±?257?kcal?×?day?1 ranging from 1324 to 2068?kcal?×?day?1. Bland–Altman analyses revealed negative mean bias but similar limits of agreement between measured REE and scores predicted by Chun, Cunningham, Mifflin, Nightingale and Gorgey, and Owen models in elite athletes who play wheelchair rugby.Conclusion: Prediction models regressed on persons with and without SCI under-predicted REE of competitive wheelchair rugby athletes. This outcome may be explained by the higher REE/fat-free mass (FFM) ratio of current athletes compared to less active samples. Findings from the current study will help practitioners to determine nutrient intake needs on training days of varied intensity. 相似文献
8.
9.
10.
Marta López-Fauqued Laura Campora Frédérique Delannois Mohamed El Idrissi Lidia Oostvogels Ferdinandus J. De Looze Javier Diez-Domingo Thomas C. Heineman Himal Lal Janet E. McElhaney Shelly A. McNeil Wilfred Yeo Fernanda Tavares-Da-Silva 《Vaccine》2019,37(18):2482-2493