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Typhoid fever is endemic in the Neapolitan area, where its yearly incidence rate largely exceeds the corresponding national figure. During the period from January to June, 1990, a matched case-control study was carried out in order to identify risk factors of the disease in this area; 51 subjects (mean age 27.2 years) with typhoid fever were compared with 102 controls matched with respect to age, sex and educational level. Consumption of raw shellfish was reported by 76.5% of the cases, as opposed to 19.6% of the controls (P < 0.01). Subjects who had eaten this food item had a 13.3-fold risk (C.I. 95% = 5.5 - 32.8) of contracting typhoid fever. In contrast, no risk was found to be associated with consumption of cooked shellfish, raw vegetables, ice-cream, non-potable water, or unpasteurized milk.The risk factor identified in this study shows that hazardous dietary habits and inadequate sewage treatment facilities, combined with lack of sanitation in the harvesting and marketing of shellfish, play a major role in the endemicity of typhoid fever in the Neapolitan area.Corresponding author.  相似文献   
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Microinjections of Leu-enkephalin into the dorsal vagal complex induced hypotension and bradycardia. Both naloxone, given at a dose conferring selectivity for μ receptors, and the S antagonist ICI 154,129 prevented the cardiovascular effects of Leu-enkephalin. Naloxone was also found to decrease the gain of the baroreflex. These results suggest that Leu-enkephalin is involved in cardiovascular regulation through activation of δ-, and possibly μ-, opioid receptors in the dorsal vagal complex.  相似文献   
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OBJECTIVES: Beh?et's disease (BD) is a chronic inflammatory disorder of still unknown etiology, characterized by endothelial cell injury/dysfunction and thrombosis and/or aneurysm of large blood vessels. Thrombophilia may play a role in the pathogenesis of thrombosis in BD. The common inherited gene defects, factor V (FV) 1691A (Leiden) and prothrombin (PT) 20210A, are known risk factors for thrombosis. The FV 4070G polymorphism was shown to influence circulating FV levels and to contribute to the activated protein C resistance phenotype. The aim of the study was to evaluate the role of FV 1691A, FV 4070G and PT 20210A gene mutations in Turkish BD patients with and without venous thrombosis. METHODS: Seventy-one patients with BD (27 with venous thrombosis) and 91 healthy subjects were included in the study. FV 1691A, FV 4070G, and PT 20210A mutations were determined by a method based on PCR-RFLP. RESULTS: The frequency of FV 1691A heterozygous mutation in BD patients with venous thrombosis (25.9%) was significantly higher than that in healthy subjects (8.8%; OR = 3.63; 95% CI 1.18-11.2). Although the frequency of this mutation in patients with venous thrombosis was higher than that in the patients without venous thrombosis (11.4%), the difference did not reach a statistically significant level (OR = 2.73; 95% CI 0.77-9.70). In BD patients with thrombosis, the frequencies of FV 4070G and PT 20210A were not significantly different compared to the BD patients without venous thrombosis and healthy subjects. CONCLUSIONS: Our results suggest that the FV 1691A, FV 4070G, and PT 20210A mutations are unlikely to play an important role in the pathogenesis of thrombosis in patients with BD.  相似文献   
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Background and aimsThe influence of lifestyle is well documented, especially the diet regime, in the development of type 2 diabetes (T2D) and associated cardiovascular diseases. Diabetic patients have increased risk of suffering cardiac ischemia and impaired response to such accidents. Methylglyoxal (MG) circulates at high concentration in diabetics' blood and is linked to the development of diabetes chronic complications. We propose that besides promoting the cardiovascular disease, MG may also negatively regulate the endogenous cardioprotection pathways after ischemia.Methods and resultsWe performed a comparative study between three animal groups: normal Wistar (W), type 2 diabetic non-obese Goto-Kakizaki (GK) and normal rats submitted to MG chronic administration (3months) with gradually enhanced concentration, up to 75 mg/Kg (WMG). Hearts were submitted to different experimental conditions: control, ischemia and ischemia-reperfusion. Levels of oxidative stress markers, advanced glycation end-products (AGEs) and their receptors (RAGEs) were evaluated. The serine/threonine protein kinase Akt (Akt), crucial for cardiomyocytes recovery after ischemia, and apoptosis markers were also assessed.Levels of MG, systemic and cardiac oxidative stress markers, AGEs and RAGEs were similar in GK and WMG groups. Akt protein was negatively regulated by MG, leading to impaired apoptotic markers.ConclusionChronic MG administration to normal rodents mimicked most diabetic alterations, being associated with the development of cardiovascular disease and the impairment of survival pathways. Our results demonstrate the negative effect of MG rich diet in healthy animals and suggest the potential of methylglyoxal as a therapeutic target in diabetes.  相似文献   
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