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41.

Background  

Influenza surveillance systems provide important and timely information to health service providers on trends in the circulation of influenza virus and other upper respiratory tract infections. Online dissemination of surveillance data is useful for risk communication to health care professionals, the media and the general public. We reviewed national influenza surveillance websites from around the world to describe the main features of surveillance data dissemination.  相似文献   
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Thallium-201/technetium-99m pertechnetate subtraction scintigraphy of the parathyroid glands was performed in a prospective study of 33 patients who had undergone bilateral neck exploration for elevated serum calcium and serum parathyroid hormone levels. In 31 cases, the Tl-201/Tc-99m subtraction technique yielded an overall sensitivity of 81%, specificity of 99%, and accuracy of 94% for identifying solitary parathyroid adenomas. Tl-201/Tc-99m subtraction scintigraphy correctly identified 73% of parathyroid adenomas weighing less than 499 mg, 79% of those weighing 500-1,499 mg, and 100% of adenomas weighing more than 1,500 mg. In a subgroup of 24 patients with solitary parathyroid adenomas who underwent both scintigraphy and high-resolution sonography, the sensitivity, specificity, and accuracy of both procedures were similar.  相似文献   
43.
BACKGROUND: By 2016, the proportion of Canadians older than 65 years of age will increase to 16%, and there will be an increase in the absolute number of cases of cardiovascular disease in older Canadians. The Canadian Heart Health Surveys database provides information about this population upon which health policy related to cardiovascular disease can be based. This paper presents for the first time population-based data on the risk factors for cardiovascular disease in older Canadians. METHODS: Canadians from all 10 provinces participated in surveys of cardiovascular risk factors; health insurance registries were used as sampling frames. In each province, probability samples of 2200 adults 18 to 74 years old not living in institutions, on reserves or in military camps were asked to participate in interviews and to undergo testing at clinics for major risk factors for cardiovascular disease. RESULTS: A total of 2739 men (response rate 70%) and 2617 women (response rate 66%) aged 55 to 74 years participated in the survey and also provided follow-up clinical measurements at the clinic. Overall, 52% of participants were hypertensive, 26% had isolated systolic hypertension, and 30% had a total blood cholesterol level of 6.2 mmol/L or greater. Rates of current smoking were lower in women than men (17% v. 22%). Overall, 87% of men and 78% of women who were current smokers smoked at least 10 cigarettes per day. Only slightly more than half of participants exercised at least once a week for at least 15 minutes, and almost half had a body mass index of 27 or greater. In only 4% was no major risk factor for cardiovascular disease detected. INTERPRETATION: Significant numbers of older Canadians have one or more major risk factors for cardiovascular disease. Many of these risk factors are amenable to modification.  相似文献   
44.
Current synthetic vascular prostheses do not acquire lining of vascular endothelium in humans or dogs. Endothelial seeding of vascular grafts has been proposed as a means of reducing the thrombogenicity of these grafts. We examined feasibility of cultivating endothelial cells (EC) by tissue culture technique and their subsequent seeding onto small diameter polytetra fluoroethylene (PTFE) grafts. Twenty adult dogs underwent common carotid artery interposition with 4 mm PTFE grafts. Ten dogs received seeded and the remaining ten received unseeded grafts. Grafts were removed at 4 and 12 weeks and their gross/morphological features compared. Cumulative patency rates for seeded grafts were 70% as compared to unseeded ones 30%. Seeded grafts were completely surfaced with a mono-layer of endothelium by 4 weeks. Small graft patency appears to be related to the establishment of an endothelial surface, the development of which is clearly facilitated by seeding with autogenous endothelium.KEY WORDS: Endothelial cell seeding, Vascular grafts  相似文献   
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血小板冷藏会使血管假性血友病因子受体复合物(von Willebrand factor receptor complex)聚集成簇。巨噬细胞αMβ2 整合素结合在成簇复合物的GPIbα亚基,导致输注的冷藏血小板被快速清除。因此输注用血小板不能冷藏,但现在的室温保存方式也存在很大缺点。我们已证明αMβ2是一种凝集素,它能识别GPIbα的N-连接葡聚糖上暴露的β-N-乙酰葡萄胺。冷藏血小板的酶促半乳糖苷化阻止了αMβ2的这种识别,延长了有  相似文献   
50.

Aim

Right ventricular (RV) systolic function in patients with hypertensive heart disease (HHD) is not well characterised. The primary aim of this study was to assess the systolic function of the right ventricle in patients with HHD using tricuspid annular-plane systolic excursion (TAPSE).

Methods

The study was cross-sectional in design and carried out in Kano, Nigeria. Patients were recruited if they had HHD on echocardiography and were at least 15 years of age. Patients with other cardiac pathologies such as ischaemic and valvular heart diseases were excluded. Patients were considered to have abnormal RV systolic function if they had reduced values of TAPSE (< 15 mm). A p-value of < 0.05 was considered statistically significant.

Results

A total of 186 patients were serially recruited over seven months. Of these, 131 (70.4%) had normal RV systolic function (group 1) and 55 patients (29.6%) had abnormal function (group 2). Group 2 patients were older (p = 0.002) and had a higher prevalence of peripheral oedema (p = 0.002), moderate to severe dyspnoea, higher heart rate and lower left ventricular ejection fraction (p < 0.001). Atrial arrhythmias were also more prevalent among group 2 patients (p < 0.05). The best correlate to TAPSE was the septal mitral annularplane systolic excursion (r = +0.541, p < 0.001). Several variables such as age predicted the presence of reduced TAPSE.

Conclusion

The study found that almost one-third of patients with HHD in Kano had RV systolic dysfunction as defined by reduced TAPSE, and these patients had a greater prevalence of factors associated with morbidity and mortality.  相似文献   
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