全文获取类型
收费全文 | 2974篇 |
免费 | 233篇 |
国内免费 | 31篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 18篇 |
妇产科学 | 14篇 |
基础医学 | 112篇 |
口腔科学 | 57篇 |
临床医学 | 463篇 |
内科学 | 230篇 |
皮肤病学 | 10篇 |
神经病学 | 98篇 |
特种医学 | 160篇 |
外科学 | 107篇 |
综合类 | 463篇 |
一般理论 | 1篇 |
预防医学 | 902篇 |
眼科学 | 8篇 |
药学 | 235篇 |
1篇 | |
中国医学 | 305篇 |
肿瘤学 | 39篇 |
出版年
2024年 | 7篇 |
2023年 | 51篇 |
2022年 | 76篇 |
2021年 | 141篇 |
2020年 | 132篇 |
2019年 | 117篇 |
2018年 | 95篇 |
2017年 | 71篇 |
2016年 | 94篇 |
2015年 | 108篇 |
2014年 | 210篇 |
2013年 | 206篇 |
2012年 | 182篇 |
2011年 | 239篇 |
2010年 | 206篇 |
2009年 | 146篇 |
2008年 | 164篇 |
2007年 | 174篇 |
2006年 | 125篇 |
2005年 | 110篇 |
2004年 | 108篇 |
2003年 | 79篇 |
2002年 | 50篇 |
2001年 | 46篇 |
2000年 | 46篇 |
1999年 | 30篇 |
1998年 | 25篇 |
1997年 | 17篇 |
1996年 | 15篇 |
1995年 | 22篇 |
1994年 | 15篇 |
1993年 | 10篇 |
1992年 | 8篇 |
1991年 | 9篇 |
1990年 | 14篇 |
1989年 | 11篇 |
1988年 | 11篇 |
1987年 | 6篇 |
1986年 | 2篇 |
1985年 | 9篇 |
1984年 | 7篇 |
1983年 | 3篇 |
1982年 | 7篇 |
1981年 | 6篇 |
1980年 | 5篇 |
1979年 | 4篇 |
1978年 | 6篇 |
1977年 | 2篇 |
1976年 | 5篇 |
1973年 | 2篇 |
排序方式: 共有3238条查询结果,搜索用时 31 毫秒
1.
2.
Paul Roderick Ruth Davies Chris Jones Terry Feest Steve Smith Ken Farrington 《Nephrology, dialysis, transplantation》2004,19(3):692-701
BACKGROUND: The demand for renal replacement therapy (RRT) in England has risen steadily, although from a lower base than many other developed countries. Predicting the future demand for RRT and the impact of factors such as the acceptance rate, transplant supply and patient survival, is required in order to inform the planning of such services. METHODS: A discrete event simulation model estimates the future demand for RRT in England in 2010 for a range of scenarios. The model uses current prevalence and current and projected future acceptance rates, survival rates and the transitions between modalities to predict future patient numbers. National population and mortality data, published literature and data from the UK Renal Registry and UK Transplant, are used to estimate unmet need for RRT, the impact of changing demography and incidence of Type 2 diabetes, patient haemodialysis (HD) survival and transplant supply. RESULTS: By 2010 the predicted prevalence will have increased from about 30,000 in 2000 to between 42 and 51,000 (900-1000 p.m.p.), an average annual growth of 4.5-6%. Changing transplant supply has a small effect on overall numbers but changes the proportion of patients with functioning graft by up to 8%. Even with an optimistic increase in transplant supply (11% p.a. for 5 years), numbers on HD will continue to rise substantially, especially in the elderly. The factors most influencing future patient numbers are the acceptance rate and dialysis survival. CONCLUSION: This model predicts a substantial growth in the RRT population to 2010 to a rate approaching 1000 p.m.p., particularly in the elderly and those on HD, with a steady state not being reached for at least 25 years. 相似文献
3.
本实验研究血液与非血液灌流条件下缺血预处理(IP)对心肌的保护作用。应用离体大鼠Langendorf灌流模型,分血液灌流IP组、非血液(KrebsHenseleit液,KH液)灌流IP组及相应的对照组。测量心肌电生理特性等指标。结果与KH液灌流心脏相似,用血液灌流的大鼠心脏经IP后,在随后的停灌和复灌期间,心室颤动阈升高,心律失常发生率明显降低。实验结论为在用血液灌流离体大鼠心脏模型上,IP对心肌的保护作用与用生理溶液灌流的模型基本相同。 相似文献
4.
Bo-Lennart Johansson Ulla Berg Ulla Freyschuss Kerstin Hall Staffan Troell 《Pediatric nephrology (Berlin, Germany)》1990,4(6):589-592
The influence of metabolic control (HbA1c), noradrenaline (NA) and insulin-like growth factors (IGF-I and IGF-II) on renal function and size was investigated in 11 insulin-dependent diabetes mellitus patients aged 11–17 years. Renal function was evaluated in terms of glomerular filtration rate (GFR) and effective renal plasma flow (ERPF). Renal size was determined as renal parenchymal volume (RPV) by ultrasonography. The patients' HbA1c values ranged from 8.2% to 12.9% (normal range 5.5–8.5%) and their GFR and ERPF were higher than normal. Their IGF-II values were higher, and NA and IGF-I levels were lower than those of healthy controls. Inverse correlations between NA and GFR (r=–0.66) and NA and ERPF (r=–0.63) were found. No correlation was found between serum IGF-I and renal functional parameters. The IGF-II values correlated with GFR and HbA1c (r=0.63,r=0.70 respectively). There were linear correlations between RPV and GFR, RPV and ERPF, HbA1c and GFR, and ERPF and RPV. Decreased NA concentrations and increased IGF-II values appear to be factors contributing to renal hyperfunction in these patients. 相似文献
5.
Christopher J. Holmgren Esmonde F. Corbet L. P. Lim 《Community dentistry and oral epidemiology》1994,22(5):396-402
Abstract The aim of this study was to describe the periodontal conditions in 372 35–44-yr-old and 537 noninstitutionalized 65–74-yr-old Hong Kong Chinese who were examined clinically for loss of attachment, recession, probing depth, calculus, and bleeding after probing. Community Periodontal Index (CPI) data and treatment need indications were compiled from index teeth or their substitutes. The prevalence of loss of attachment varied considerably in both cohorts according to the definition of the threshold (≥6, ≥9, and ≥12 mm, respectively). The mean numbers of teeth with loss of attachment at the ≥6-mm threshold and at higher thresholds were small. In both age cohorts, about one-fifth of subjects had probing depths ≥6-mm, while al the ≥9-mm threshold only 2–3% were so affected. Although recession was an important component of loss of attachment in the younger cohort, in the older cohort the prevalence and extent of recession were greater than for probing depths at thresholds ≥4 mm. All subjects had one or more teeth with calculus, bleeding, or both, most teeth being so affected. Eighty-four of the 537 65–74-yr-old subjects were excluded either because of edentulousness or because extractions indicated for the remaining teeth would have rendered the subjects edentulous. The distribution of subjects according to their highest CPI score was remarkably similar for the two cohorts. No subjects in either age group were assessed as “healthy” (CPI code 0) or had “bleeding only” (code 1) as their highest score. While most subjects scored CPI code 2 or 3 us their highest score, only 17% of the younger and 15% of the older cohort scored Community Periodontal Index of Treatment Needs (CPITN) code 4. Differences in the mean number of sextants affected by CPI codes between the two cohorts were mainly due to a greater number of excluded sextants in the older cohort. CPI findings for 35–44-yr-olds differed little from those reported in 1984. 相似文献
6.
汪国翠 《安徽卫生职业技术学院学报》2003,2(5):83-84
根据笔者在传染科病房工作中的体会,从六个方面针对传染科工作的特殊性和存在的共性分别阐述了传染科护士在工作中如何高标准、严要求自己,如何对病人做到到位的护理,旨在提高传染科病房的整体护理质量,从而把更多的实惠让利于患者。 相似文献
7.
R. J. Rona A. V. Swan R. Beech D. M. Wilson F. B. Kavanagh C. Brown C. Axtell S. Mandalia 《Clinical genetics》1992,42(4):186-195
For certain genetic conditions DNA testing identifies carriers and determines the risk status of foetuses, thus helping parents to make more informed prenatal decisions. Data, collected from three genetic centres in England and Wales from August 1986 to July 1990, are used to describe trends in demand for DNA testing, the impact of DNA tests on carrier risk assessment, and the use of DNA tests in relation to pregnancy outcome. Altogether the data include 23,388 subjects and 681 pregnancies in 8738 families divided into five cohorts by year of entry and referral. The most frequent gene disorders referred to the genetic centres are currently being tested or will soon be tested. For these disorders the initial high level of activity has declined and may have reached steady state. Demand for DNA services is high for cystic fibrosis and Duchenne muscular dystrophy, intermediate for Huntington's disease, and low for adult polycystic kidney disease, phenylketonuria and tuberous sclerosis. Based on these findings we suggest that demand for DNA tests will be high in serious, untreatable and slow progressing conditions with early onset; intermediate for conditions affecting intellect and neurological integrity with later onset; and low for treatable, late-onset conditions, or those for which there is evidence of heterogeneity, and variable penetrance. It would be helpful to assess the extent to which this view of demand is confirmed when the new disorders being DNA tested are considered and for the pattern of activity of DNA testing for some types of cancer. Since no DNA centre could offer a fully comprehensive testing service, it is recommended that a structure is created to audit overall activity, assist in policy formulation, and influence supraregional service organisation, in order that the spread of DNA services be planned as effectively as possible. This structure would facilitate monitoring of the evolution of contract specifications agreed by commissioners and providers on a regional basis. 相似文献
8.
人群归因危险度百分比 (populationattributableriskproportion ,PARP)是总体人群中某种疾病归因于某种因素的暴露所引起的发病 (死亡 )占全部发病 (死亡 )的百分比 ,反映该因素所引起的发病 (死亡 )占全部发病 (死亡 )的比重。通过PARP可了解各危险因素对人群中某疾病的发病所产生的影响 ,亦即消除某危险因素后 ,所产生的对预防该疾病的效果将占有多大比重。它能够为卫生政策的制订提供依据 ,有着重要的公共卫生的实际意义。目前常用的估计PARP的方法有两种 :一种是利用全国人群抽样调查获得的人群总暴露率来估计 ;另一种是利用某地区… 相似文献
9.
10.
目的筛选对解脲支原体和白色念珠菌体外有明显抑制作用的抗H IV中药有效成分,为治疗H IV继发感染或性病奠定基础。方法以微量稀释法测定9种中药有效成分对解脲支原体和白色念珠菌的M IC50和M IC90,同时测定其中6种中药有效成分对H IV-1的EC50和TI值。结果所测药物对解脲支原体、白色念珠菌及H IV-1均有一定的抑制作用,对解脲支原体和白色念珠菌作用最好的分别是三七总皂苷、三七叶皂苷和化合物A,化合物A对H IV-1的抑制作用最好,其EC50为0.09,TI值大于10 000。结论化合物A对解脲支原体、白色念珠菌及H IV-1的抑制效果最好,值得进一步研究。 相似文献