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Dental caries and mutans streptococci in relation to plasma ascorbic acid   总被引:1,自引:0,他引:1  
Ascorbic acid (AA) affects in vitro growth of bacteria and may also act in vivo to decrease caries activity. The aim of this study was to evaluate the possible association of AA level in plasma with number of caries lesions, relative numbers of some species of oral cariogenic flora, and rate of salivary secretion. The caries status and some bacteriologic variables of dentulous adult subjects with a low level of AA in the plasma (≤25 μmol/1; n =75) were compared with those of controls (plasma level ≥50 μmol/1; n =75) matched for age, sex, and number of teeth. For each subject, site-specific recordings of the presence or absence of plaque, dental caries, fillings, and erosions were recorded clinically by the same dentist in a double-blind system. The amounts of visible plaque and numbers of decayed tooth surfaces were significantly higher in the low AA group than in the controls. No between-group differences were found in the number of fillings and the amount of oral bacterial growth. The frequencies of consumption of vegetables, berries, and other fruit were significantly lower in the low AA group than in the controls.  相似文献   
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The relative aerobic strain (RAS) of nonmotorized mail delivery was assessed in 54 Finnish mail carriers who represented both sexes, the entire workage range and both downtown and suburban delivery districts. The mean RAS of the entire delivery time was 55% of the maximal oxygen uptake (ml/kg-min). It was higher for women than for men, and higher for suburban than for downtown delivery. The RAS tended to increase systematically with age after the age of 50. The work strain of mail carriers of over 50 years of age, especially of older women carriers in suburban areas, was concluded to be high enough to lead to possible excessive strain on the workers.  相似文献   
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OBJECTIVE: To study the incidence and risk factors of stroke after coronary artery bypass grafting (CABG) or percutaneous transluminal coronary angioplasty (PTCA). DESIGN: During 1983-1992, coronary revascularization procedures (n = 2160) were recorded in patients aged 35-64 years as part of the population-based FINMONICA Myocardial Infarction Register. The FINMONICA Stroke Register and National Hospital Discharge Register were used to ascertain subsequent stroke events in such patients. RESULTS: During the average follow-up of 5.83 years, 155 patients (7.2%) had a stroke. The cumulative incidence of stroke was 1.55% in the first year after revascularization and varied between 0.8 and 1.4% during subsequent years. In Cox proportional hazard models the relative risk of stroke was 3.01 (p = 0.0007) for a previous stroke, 2.61 (p = 0.0001) for diabetes mellitus, 2.15 (p = 0.007) for low income (compared with high income), 2.06 (p = 0.03) for male sex, and 1.43 (p = 0.02) for a 10-year increment in age. CONCLUSION: The incidence of stroke during the first year after revascularization was five times higher than among the age- and sex-matched general population. Patients with a previous stroke, diabetes mellitus, advanced age, male sex and low socioeconomic status need special attention because of increased risk of stroke after CABG or PTCA.  相似文献   
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