全文获取类型
收费全文 | 760篇 |
免费 | 100篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 63篇 |
妇产科学 | 38篇 |
基础医学 | 124篇 |
口腔科学 | 9篇 |
临床医学 | 85篇 |
内科学 | 145篇 |
皮肤病学 | 2篇 |
神经病学 | 40篇 |
特种医学 | 50篇 |
外科学 | 124篇 |
综合类 | 28篇 |
预防医学 | 66篇 |
眼科学 | 23篇 |
药学 | 49篇 |
肿瘤学 | 18篇 |
出版年
2022年 | 5篇 |
2021年 | 7篇 |
2020年 | 5篇 |
2019年 | 5篇 |
2018年 | 9篇 |
2017年 | 7篇 |
2016年 | 18篇 |
2015年 | 17篇 |
2014年 | 15篇 |
2013年 | 30篇 |
2012年 | 33篇 |
2011年 | 28篇 |
2010年 | 15篇 |
2009年 | 21篇 |
2008年 | 26篇 |
2007年 | 47篇 |
2006年 | 31篇 |
2005年 | 42篇 |
2004年 | 36篇 |
2003年 | 24篇 |
2002年 | 21篇 |
2001年 | 28篇 |
2000年 | 25篇 |
1999年 | 26篇 |
1998年 | 14篇 |
1997年 | 15篇 |
1996年 | 12篇 |
1995年 | 12篇 |
1994年 | 11篇 |
1993年 | 15篇 |
1992年 | 25篇 |
1991年 | 14篇 |
1990年 | 17篇 |
1989年 | 27篇 |
1988年 | 17篇 |
1987年 | 22篇 |
1986年 | 13篇 |
1985年 | 10篇 |
1983年 | 8篇 |
1982年 | 8篇 |
1981年 | 8篇 |
1980年 | 6篇 |
1979年 | 8篇 |
1978年 | 10篇 |
1977年 | 14篇 |
1976年 | 5篇 |
1975年 | 5篇 |
1971年 | 6篇 |
1970年 | 9篇 |
1968年 | 5篇 |
排序方式: 共有867条查询结果,搜索用时 15 毫秒
71.
72.
Marcus R. Keogh‐Brown Simon Wren‐Lewis W. John Edmunds Philippe Beutels Richard D. Smith 《Health economics》2010,19(11):1345-1360
Little is known about the possible impact of an influenza pandemic on a nation's economy. We applied the UK macroeconomic model ‘COMPACT’ to epidemiological data on previous UK influenza pandemics, and extrapolated a sensitivity analysis to cover more extreme disease scenarios. Analysis suggests that the economic impact of a repeat of the 1957 or 1968 pandemics, allowing for school closures, would be short‐lived, constituting a loss of 3.35 and 0.58% of GDP in the first pandemic quarter and year, respectively. A more severe scenario (with more than 1% of the population dying) could yield impacts of 21 and 4.5%, respectively. The economic shockwave would be gravest when absenteeism (through school closures) increases beyond a few weeks, creating policy repercussions for influenza pandemic planning as the most severe economic impact is due to policies to contain the pandemic rather than the pandemic itself. Accounting for changes in consumption patterns made in an attempt to avoid infection worsens the potential impact. Our mild disease scenario then shows first quarter/first year reductions in GDP of 9.5/2.5%, compared with our severe scenario reductions of 29.5/6%. These results clearly indicate the significance of behavioural change over disease parameters. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
73.
Percutaneous balloon dilatation of aortic valve stenosis in neonates and infants. 总被引:3,自引:3,他引:0
下载免费PDF全文
![点击此处可从《Heart (British Cardiac Society)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Percutaneous balloon dilatation of severe aortic valve stenosis was attempted in thirteen patients (seven neonates and six infants). In two the valve could not be crossed and both died during subsequent operation. Two patients died during manipulation of the balloon catheter. No significant benefit was obtained in another patient who later died during operation. Balloon dilatation was successful in the remaining eight patients, reducing the aortic valve pressure gradient from a mean of 63 mmHg (95% confidence interval 38 to 88 mmHg) to a mean of 23 mmHg (95% confidence interval 7 to 39 mmHg). Two of these patients subsequently died from heart failure related to other cardiac lesions. The six survivors have done well. At follow up the maximum Doppler velocities in the ascending aorta ranged from 1.9 to 4.0 m/s after 2-23 months, but despite this evidence of an increasing valve gradient there has been lasting clinical improvement. 相似文献
74.
Acute myocardial infarction in infancy: unmasking of anomalous origin of the left coronary artery from the pulmonary artery by ligation of an arterial duct.
下载免费PDF全文
![点击此处可从《Heart (British Cardiac Society)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Myocardial infarction and left ventricular failure developed within hours of ligation of a large arterial duct in a four week old infant. Anomalous origin of the left coronary artery from the pulmonary artery was confirmed by echocardiography. Despite emergency translocation of the anomalous coronary artery the patient died. 相似文献
75.
76.
77.
Studies on 24 Wr(a+b+) and 23 Wr(a-b+) blood samples, using anti-Wrb in the enzyme-linked antiglobulin test (ELAT), have shown that Wr(a+b+) red cells bind, on average, a little over half the amount of anti-Wrb bound by Wr(a-b+) red cells. Similarly, ELAT studies using six different anti-Wra and 10 Wr(a+b+) samples, as well as red cells from the original Wr(a+b-) proposita, have shown that Wr(a+b+) red cells bind about half the amount of anti-Wra bound by Wr(a+b-) red cells. Various pitfalls that can arise when the ELAT is used to measure antigen ratios on red cells have been avoided but are described. This conclusive evidence that Wra and Wrb have an antithetical relationship is discussed in light of the knowledge that a ficin-resistant portion of MN sialoglycoprotein (SGP), when carried in liposomes, can inhibit anti-Wrb. It is possible that Wra, Wrb, or both may encode a post-translational change in MN SGP, or production of transferases that glycosylate membrane lipids that affect in situ orientation of MN SGP, or production of protein band 3 that then forms a complex with MN SGP at the red cell membrane surface. 相似文献
78.
目的:比较师范院校贫困新生与非贫困新生的心理健康状况。方法:于2005-10在衡阳师范学院完成调查。采用整群抽样横断面调查方法,以衡阳师范学院2005级3089名新生为调查对象,运用症状自评量表对其进行集体测查。在统一指导语下,学生根据最近1周内的自我感觉答题,独立完成,当场收卷。结果数据运用光电阅读机(OMR2000)输入计算机心理测评工具箱标准版V3.0系统进行总分和因子分的统计。量表中没有回答的项目记为"没有",5个以上项目未答者视为问卷无效以及总分低于95分的问卷因缺乏可靠性均不进行分析。所有数据输入电脑后用SPSS11.0软件进行统计分析;群体差异比较用t和Z检验。结果:共发放3089份问卷,收回有效答卷2994份,有效率为96.92%,其中贫困新生有效答卷510份,占17.03%。问卷结果显示,师范院校贫困新生在人际关系、偏执和精神病性3项因子上的得分分别为1.86±0.54,1.70±0.48和1.58±0.43,明显高于非贫困新生(1.78±0.51,1.65±0.46,1.53±0.39,t=3.34,2.02,2.92,P<0.05)。从阳性因子的人数比率来看,师范院校贫困新生在总分阳性的人数比率为0.28,明显低于非贫困新生(0.33,Z=-2.27,P<0.05);而在人际关系、偏执和精神病性3项因子阳性的人数比率分别为0.35,0.30,0.16,明显高于非贫困新生(0.31,0.24,0.13,Z=1.73,2.72,1.71,P<0.05)。结论:师范院校贫困新生的整体心理健康状况并不比非贫困新生差,但是在人际关系敏感、偏执和精神病性3个问题上明显比非贫困新生要严重。 相似文献
79.
Guidelines for the laboratory diagnosis and susceptibility testing of methicillin-resistant Staphylococcus aureus (MRSA) 总被引:4,自引:0,他引:4
Brown DF Edwards DI Hawkey PM Morrison D Ridgway GL Towner KJ Wren MW;Joint Working Party of the British Society for Antimicrobial Chemotherapy;Hospital Infection Society;Infection Control Nurses Association 《The Journal of antimicrobial chemotherapy》2005,56(6):1000-1018
These evidence-based guidelines have been produced after a literature review of the laboratory diagnosis and susceptibility testing of methicillin-resistant Staphylococcus aureus (MRSA). We have considered the detection of MRSA in screening samples and the detection of reduced susceptibility to glycopeptides in S. aureus. Recommendations are given for the identification of S. aureus and for suitable methods of susceptibility testing and screening for MRSA and for S. aureus with reduced susceptibility to glycopeptides. These guidelines indicate what tests should be used but not when the tests are applicable, as aspects of this are dealt with in guidelines on control of MRSA. There are currently several developments in screening media and molecular methods. It is likely that some of our recommendations will require modification as the new methods become available. 相似文献
80.
目的:由于技术原理的限制,目前尚不能对所有的HLA等位基因进行严格的区分,特别是以往没有发现的新基因序列只能通过测序的方法解决,然而,当遇到等位基因杂合时,测序给出的结果仍然无法确认新的序列改变发生在等位基因的哪一侧,这时需要用分子生物学方法分离杂合子然后进行测序才能确定新的基因序列。采用基因克隆方法确认HLA新等位基因。
方法:实验于2006-01/05在河南省红十字血液中心HLA实验室,美国海军骨髓库HLA实验室完成。造血干细胞血样由中华骨髓库提供。采用荧光微珠HLA分型方法对中华骨髓库捐献者血样进行HLA分型检测,无法给出确切结果的摸棱两可结果标本用基因克隆(TOPO TA Cloning)、DNA测序的方法确认新的HLA基因序列。
结果:通过克隆分离杂合等位基因,再进行测序确认发现新的序列与B^*3709相比,出现4个核苷酸改变:1.355nt C〉A,2.363nt C〉G,3.412nt G〉A,4.477ntC〉G,而且均发生在H哺B基因外显子3(exon3)。4处改变引起氨基酸编码改变:①编码95CTC〉ATC,氨基酸改变L〉1(亮氨酸〉异亮氨酸)。②97AGC〉AGG.S〉R(丝氨酸〉精氨酸)。③114GAC〉AACD〉N(天门冬氨酸〉天冬酰胺)。(9135GCC〉GCGA=A无氨基酸改变。
结论:①新的基因序列已经在GenBnak注册,被WHO的HLA因子命名委员会得到正式命名为HLA-B^*3712基因。②基因克隆是确认HLA新基因的根本方法。 相似文献