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Artemisinin-based combination therapies (ACTs) are currently considered the first-line treatments for uncomplicated Plasmodium falciparum malaria. Among these, artemether-lumefantrine (AL) has been the most widely prescribed ACT in sub-Saharan Africa. Recent clinical trials conducted in sub-Saharan Africa have shown that dihydroartemisinin-piperaquine (DP), a most recent ACT, may have a longer post-treatment prophylactic period and post-treatment infection period (duration of gametocyte carriage) than AL. Using epidemiological and clinical data on the efficacy of AL and DP, we developed and parameterized a mathematical transmission model that we used to compare the population-level impact of AL and DP for reducing P. falciparum malaria transmission in sub-Saharan Africa. Our results showed that DP is likely to more effectively reduce malaria incidence of clinical episodes than AL. However in low P. falciparum transmission areas, DP and AL are likely to be equally effective in reducing malaria prevalence. The predictions of our model were shown to be robust to the empirical uncertainty summarizing the epidemiological parameters. DP should be considered as a replacement for AL as first-line treatment of uncomplicated malaria in highly endemic P. falciparum communities. To optimize the effectiveness of ACTs, it is necessary to tailor treatment policies to the transmission intensity in different settings.  相似文献   
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Journal of Thrombosis and Thrombolysis - Although certain risk factors have been associated with morbidity and mortality, validated emergency department (ED) derived risk prediction models specific...  相似文献   
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背景目前已开展了对重性精神病患者进提供连续性服务的研究。目的探讨基层对有抑郁症风险患者提供连续性服务的水平,并与对心力衰竭患者的服务水平进行对比。方法采用抑郁症风险患者与心力衰竭患者对比的探索性研究。采用患者问卷评估服务的持续性,包含如下内容:(1)联系的服务提供者数(个人连续性);(2)诊所内服务提供者之间的合作(团队连续性)(6个项目,分数1~5分);(3)诊所外全科医师与服务提供者之间的合作(跨界连续性)(4个项目,分数1~5分)。结果大多数抑郁症风险患者在过去1年中寻遍整个服务提供界联系了几个服务提供者,曾遇到过高水平团队连续性服务及低水平跨界连续性服务。在诊所中可接触到的不同服务提供者要明显多于心力衰竭患者服务提供者(P<0.01)。抑郁症风险患者的服务提供者之间的合作更好一些,每项平均得分4.3分,心力衰竭患者得分为4.0分(P=0.03)。然而,跨界连续性服务方面正好相反:抑郁症风险患者每项平均得分3.5分,心力衰竭患者得分为4.0分(P=0.01)。结论抑郁症风险患者与心力衰竭患者之间的探索性对比显示:体验服务连续性方面的差距不大。对此还应行进一步分析。  相似文献   
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Coronary heart disease is a major cause of morbidity and mortality in North America. Its prevention is therefore an important clinical goal. Individuals with both Type 1 and Type 2 diabetes mellitus are at increased risk of developing heart disease as compared with those without diabetes. Carotid ultrasound is now a well-validated tool to study the presence and progression of cardiovascular disease. Using ultrasound one can determine elastic properties of the vessel wall (distensibility and compliance) as well as intima-media thickness (IMT). Several large studies have shown that IMT is a useful predictor of future cardiovascular events such as myocardial infarction and stroke, and is well correlated with other traditional risk factors such as blood pressure, lipids, level of glycemic control, and smoking. For this reason, carotid ultrasound may add valuable clinical information above and beyond that provided by traditional risk factors. The use of carotid ultrasound in the pediatric and adolescent population is increasing, and one study has shown decreased distensibility in adolescents with Type 1 diabetes mellitus versus controls. However, IMT measurements in the children and teens with Type 1 diabetes have yielded conflicting results, and larger, longitudinal studies are needed in this area.  相似文献   
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OBJECTIVE: To examine whether promoter polymorphisms associated with variation in interleukin-10 (IL-10) production are relevant to the development of rheumatoid arthritis (RA) or Felty's syndrome (FS). METHODS: DNA was obtained from 44 FS patients, 117 RA patients and 295 controls. The promoter region between -533 and - 1120 was amplified by polymerase chain reaction, and polymorphisms detected by restriction enzyme digest or sequence-specific oligonucleotide probing. RESULTS: We found no significant difference in allele or haplotype frequencies between the groups. CONCLUSION: There is no association between FS or RA and these recently identified IL-10 promoter polymorphisms. Other genetic or environmental factors could explain the alterations in IL-10 levels seen in these conditions.   相似文献   
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Conclusions Laser revascularization holds promise in treating patients with angina refractory to maximal medical therapy that is deemed untreatable by percutaneous and surgical interventions. TMR has been approved by the US Food and Drug Administration, and studies have shown that it has efficacy in improving angina class and exercise performance. Advances in fiberoptics and laser technology have enabled cardiologists to evaluate a per-cutaneous nonsurgical route for laser revascularization. PMR has had promising early results and will probably become an accessible and effective means of providing relief to patients with severe coronary artery disease.  相似文献   
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