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OBJECTIVE: We examined the association between climatologic parameters and daily admissions for non-fatal acute coronary syndromes (ACS) to emergency units of hospitals in the greater Athens area, from January 2001 to August 2002. METHODS: Daily mean, maximum and minimum temperatures, relative humidity, wind speed, barometric pressure and a thermo-hydrological index (T.H.I.) were measured at the meteorological station of the Laboratory of Climatology of the Geology Department of the University of Athens. In addition, the daily number of admissions for acute myocardial infarction or unstable angina in the five major general hospitals in the greater Athens area was recorded. Generalized additive models (GAM) were applied to regress-time-series of daily numbers of outpatients with acute cardiac events against climatological variations, after controlling for possible confounders and adjustment for over dispersion and serial correlation. RESULTS: Five thousand four hundred fifty-eight Athenians with non-fatal acute cardiac events were admitted to the selected hospitals during the period of the study, 4093 (75%) males and 1365 (25%) females. There was a negative correlation between hospital admissions and mean daily temperature (MDT) with a 1 degrees C decrease in mean air temperature yielding a 5% increase in hospital admissions (P<0.05). This association was stronger in females and the elderly (P<0.01). Relative humidity was positively correlated with hospital admissions (P<0.05). CONCLUSION: Despite the relatively short study period (<2 years), these findings suggest a significant association between cold weather and increased coronary heart disease incidence, especially in the elderly and females.  相似文献   
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Immune dysfunction, which leads to the suppression of haemopoiesis by cytokines that are secreted by activated T lymphocytes, is considered to play a key role in the pathogenesis of acquired aplastic anaemia (AAA). We investigated the intracytoplasmic expression of type-1 [interferon gamma (IFN-gamma), interleukin (IL)-2] and type-2 (IL-4, IL-10) cytokines in CD4+ and CD8+ T cells before and after in vitro activation in 16 patients with AAA and 17 normal controls. Untreated or refractory patients had a significantly higher proportion of unstimulated CD4+ and CD8+ T cells that produced IFN-gamma and IL-2 whereas the IL-4 and IL-10 producing T cells did not differ from that of controls, resulting in a shift of IFN-gamma/IL-4 ratio towards a type-1 response. Patients in remission had also increased proportion of IFN-gamma-producing unstimulated CD4+ and CD8+ cells, with a parallel rise of IL-4- and IL-10-producing cells and normal IFN-gamma/IL-4 ratio. These data indicate that, in newly diagnosed and refractory patients with AAA, CD4+ cells are polarized towards a type-1 response that in turn leads to activation of cytotoxic CD8+ cells and finally to haemopoietic stem cell destruction. The type-1 response persists in patients in remission although this effect is compensated by the increase of IL-4 and IL-10 production.  相似文献   
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OBJECTIVES: Mixed cryoglobulinemia (MC) is the most common extrahepatic manifestation of HCV infection. The aim of this study is to determine the prevalence of MC in HCV infected Greek patients and to identify if it is associated with liver histology or the mode of HCV transmission. METHODS: One hundred and twenty-six patients with chronic HCV infection were evaluated for the presence of serum cryoglobulins, autoantibodies and viral markers. One hundred and eighteen of them underwent liver biopsy and each specimen was evaluated according to the grading and staging system described by Ishak et al. RESULTS: Cryoglobulins were detected in 37/126 (29.4%) HCV patients and cryocrit values ranged between 0.5 and 6.5%. Only two patients presented clear clinical manifestations of MC. In patients with MC, a higher grading (6.40+/-2.06 vs. 5.27+/-2.55, p=0.013) and staging score (3.71+/-1.45 vs. 2.83+/-1.84, p=0.007) was noted in liver biopsy compared to those without MC. Logistic regression analysis identified staging score (OR, 1.33; CI, 1.06-1.66, p=0.015) as the only independent variable associated with cryoglobulinemia. Correlation between the presence of cryoglobulins and the mode of HCV transmission was not found. CONCLUSIONS: Greek patients with chronic HCV infection have high prevalence of cryoglobulinemia. A clear association between the presence of serum cryoglobulins and staging score of chronic hepatitis was found, with no difference in patients' age or the duration of infection. It is possible that cryoglobulinemia results in more rapid hepatic fibrosis in HCV infected patients.  相似文献   
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Abdominal aortic aneurysm (AAA) is a relatively common pathology among the elderly. More people above the age of 80 will have to undergo treatment of an AAA in the future. This review aims to summarize the literature focusing on endovascular repair of AAA in the geriatric population. A systematic review of the literature was performed, including results from endovascular abdominal aortic aneurysm repair (EVAR) registries and studies comparing open repair and EVAR in those above the age of 80. A total of 15 studies were identified. EVAR in this population is efficient with a success rate exceeding 90% in all cases, and safe, with early mortality and morbidity being superior among patients undergoing EVAR against open repair. Late survival can be as high as 95% after 5 years. Aneurysm-related death over long-term follow-up was low after EVAR, ranging from 0 to 3.4%. Endovascular repair can be offered safely in the geriatric population and seems to compare favourably with open repair in all studies in the literature to date.  相似文献   
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Objective Hypercortisolaemia is associated with an increased risk of cardiovascular disease (CVD), either through a direct action on the myocardium or by increased traditional cardiovascular risk factors. The aim of this study was to investigate whether the alterations in the ECG in Cushing’s disease (CD) are predictable from risk factor analysis alone. Design In 79 patients with a diagnosis of CD, retrospectively recruited, ECG features [corrected for heart rate QT (QTc), QTc dispersion (QTcd), left ventricular hypertrophy (ECG‐LVH), right ventricular hypertrophy (ECG‐RVH)], systolic (SBP) and diastolic (DBP) blood pressure were assessed. Biochemical, hormonal (cortisol at 09·00 h or cortisol day curve, CDC) and carbohydrate abnormalities (CHA), history of hypertension and cardiovascular disease were recorded. For comparison reasons, a group of 42 healthy subjects matched for gender, age and body mass index previously subjected to ECG assessment were selected. Results In patients with CD, we noted the following prevalence: metabolic syndrome 39%, hypertension 81%, CVD 21·5%, hypercholesterolaemia 37%, hypertriglyceridaemia 29%, CHA 41%, but a history of cardiac dysrhythmia was only noted in a single patient. No difference in QTc or QTcd was shown between patients with normal or low potassium levels. QTcd >50 ms was associated with both increased ECG‐LVH and ECG‐RVH. When compared to the control group, patients had longer QTcd (P < 0·001), more prevalent LVH (P < 0·001) and RVH (P = 0·001), and higher SBP and DBP (P < 0·001), but similar QTc. Both CD and ECG evidence of LVH predicted prolonged QTcd, but the association of CD with a prolonged QTcd was independent of other risk factors, including hypertension. Conclusions Prolonged QTcd in association with ECG evidence of LVH appears to be the specific feature of CD. This may be relevant in the choice of medical therapy for CD and for consideration of treatment of the comorbidities that are associated with hypercortisolaemia.  相似文献   
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