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41.
The results of environmental (11 subjects) and biological (57 subjects) monitoring of exposure to mancozeb, ethylenethiourea (ETU), and dim ethoate are reported for employees of a firm producing commercial formulations containing these active ingredients. Urinary excretion \[GM(GSD) ] of ETU (mug/g creatinine) and alkylphosphates \[dimethylphosphate (DMP) + dimethylthiophosphate (DMTP) + dimethyldithiophosphate (DMDTP)] (nmol/g creatinine) was 65.3(4.8) and 419.2(2.1), respectively, for employees engaged in the formulation of a product containing 80% mancozeb (n= 9), 36.6(1.9) and 296.4(2.4) for those formulating a product containing 35% mancozeb (n = 9), 9.5(6.1) and 1022.4(3.0) for those engaged in plant maintenance and internal transport of materials (n = 6), 10.3(4.2) and 322.8(3.3) for those engaged in packaging the mancozeb formulations (n = 16), 4.4(3.3) and 2545.4(3.9) for those formulating a product containing 40% dimethoate (n = 11), and 3.0(2.7) and 871.7(3.3) for those bottling the same dimethoate formulation (n = 10). Air concentrations (mug/m3) ranged from 25.3 to 194.4 for dimethoate, from 0.2 to 1.3 for ETU, and from 139.9 to 949.0 for mancozeb. Urinary excretion of ETU and alkylphosphates showed a significant correlation with mancozeb (r2= .971), and ETU (r2= .858), and dimethoate (r2= .955) contamination of the hands. Potential dose estimates showed that the potential respiratory doses of mancozeb and dimethoate accounted, on the average, for 38% of the total potential dose. The potential respiratory dose of ETU was 7% of the total potential dose. Total estimated absorption did not exceed the accepted daily dose (ADI) for ETU and mancozeb, but the ADI for dimethoate was exceeded. Serum and erythrocyte cholinesterase activities in workers formulating dimethoate products were not significantly different before and after exposure.  相似文献   
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ObjectiveThe purpose of the present research was to compare the residual microbial load in Solo System microfiber mops with silver and in normal microfiber mops without silver to see whether those with the silver prevent bacterial proliferation and spread more effectively during normal cleaning operations.MethodsMops with and without silver were experimentally contaminated with suspension of Staphylococcus aureus ATCC 6538. The bioburden was evaluated by a filtering procedure according to UNI EN 1174 after contamination, after washing and after different times of impregnation in an alcohol-base detergent.Results and discussionThe results obtained lead to the conclusion that silver microfiber mop was significantly more effective in reducing bacterial load despite initial high level contamination (106-107 CFU/50 cm2). Indeed, after low temperature washing, the bacterial load was already completely eliminated while the mop without silver still presented relatively high levels of the microorganism (approximately 102 CFU/50 cm2) even after being soaked for 8 hours in a detergent/disinfectant.  相似文献   
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Percutaneous revascularization of saphenous vein grafts (SVGs) remains a challenging task. Drug-eluting stents (DESs) have been shown to decrease the incidence of restenosis in de novo native coronary artery lesions. However, their clinical value in SVGs remains to be established. We compared long-term clinical outcomes of percutaneous coronary intervention with DESs and bare metal stents (BMSs) for de novo lesions in SVGs. In a large prospective, multicenter registry, 360 patients underwent stenting of a de novo lesion in SVGs using BMSs (288 patients) or DESs (72 patients). Incidence of major adverse cardiac events (MACEs), including all-cause mortality, reinfarction, and target vessel revascularization, was recorded at a 12-month follow-up. Compared with the DES group, patients receiving BMSs were more likely to be men, to have chronic renal insufficiency or higher Charlson scores, but less likely to have undergone previous percutaneous coronary intervention. Incidence of MACEs at 12-month follow-up was similar in the 2 groups (17.8% in DES group vs 20.3% in BMS group, respectively, p = 0.460). Cox regression analysis identified age, chronic renal failure, cardiogenic shock at presentation, and ostial location of stenosis as independent predictors of long-term MACEs. In conclusion, our data suggest that rates of 12-month MACEs associated with the use of DESs and BMSs are similar in patients undergoing treatment of de novo lesions in SVGs.  相似文献   
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