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71.
Employees in the footwear manufacturing industry are routinely exposed to complex mixtures of solvents used in cleaning and as diluents in glues, primers, and degreasers. The objective of this study was to determine the genotoxic effects in a group of footwear-workers occupationally exposed to solvent-based adhesive and solutions containing organic solvents, mainly toluene. Peripheral blood and buccal cells samples were collected from 39 footwear-workers (31 males and 8 females) and 55 controls (44 males and 11 females). As biomarker of exposure, we obtained data on hippuric acid (HA), the main metabolite of toluene in urine, and DNA damage detected by the Comet assay in blood cells. Micronucleus frequencies in binucleated lymphocytes (BNMN) and in epithelial buccal cells (EBCMN) were analyzed as biomarkers of effect, while polymorphisms in genes GSTT1, GSTM1, GSTP1, CYP1A1, and CYP2E1 were used as susceptibility biomarkers. Results of HA and Comet assay showed statistical increased values amongst footwear-workers relative to controls (P < or = 0.001). No differences were observed in BNMN and EBCMN frequencies between the groups, but a correlation test revealed that age was significantly associated with BNMN frequency in both control (r(s)=0.290; P < or = 0.05) and exposed groups (r(s)=0.674; P < or = 0.001). Regarding the results on genetic polymorphisms, GSTM1 null subjects from the control group showed a significant increase in EBCMN frequency relative to GSTM1 non-null subjects (P < or = 0.05). A significant increase in DNA damage detected by Comet assay in leukocytes was obtained for GSTP1 Ile/Val or Val/Val individuals from the exposed group relative to those with GSTP1 Ile/Ile (P < or = 0.05), especially in younger subjects (P < or = 0.01), and a suggestion of interaction with CYP2E1 polymorphism was found. In confirmation of these data, stepwise multiple regression analyses for selecting between the different independent variables showed that about 25% of levels of the DNA damage in footwear-worker can be associated with genetic polymorphisms in GSTP1 and CYP2E1 (P=0.006, F=5.876).  相似文献   
72.
It is often debated that the protection against solar-induced erythema under real conditions is dependent upon the amount of sunscreen applied. It is believed that when too little is applied a lower sun protection than indicated on the label will result. The aim of this study was to quantify this effect. In this multicenter study, the influence of three different amounts (0.5, 1.0, 2.0 mg/cm(2)) of three commercial sunscreen products in three reliable test centers was investigated according to the test protocol of The International Sun Protection Factor Test Method. The main result was a linear dependence of the SPF on the quantity applied. Taking into consideration the volunteer-specific variations, an exponential dependence of confidence interval of the in vivo SPF and amount applied was found. The highest amount applied (2.0 mg/cm(2)) was linked to the lowest confidence intervals. Thus, from the point of view of producing reliable and reproducible in vivo results under laboratory conditions, the recommendation of this multicenter study is an application quantity of 2.0 mg/cm(2).  相似文献   
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Studies evaluating adverse effects of oral theophylline on learning and behavior have been performed on children with asthma receiving long-term theophylline therapy. To further differentiate the effects of asthma itself from the drugs used, we evaluated 20 asthmatic children (6 to 12 years of age) who had not received oral bronchodilators for at least 6 months. A double blind, placebo-controlled, parallel format was used with a 4-week theophylline or placebo period preceded by a 2-week baseline. Theophylline serum levels were maintained between 10 to 20 micrograms/mL. During baseline and treatment periods, the child's home and school behavior/performance were monitored independently by their parents and teachers using standardized report forms. A battery of psychologic tests was administered at the end of baseline and treatment periods. Seven children receiving theophylline were noted to have a change in school behavior and/or performance during their 4 weeks on drug compared to baseline, whereas none of the children receiving placebo were noted to be different (P = .004). Thus, the short-term administration of theophylline to asymptomatic asthmatic children not receiving oral bronchodilators can adversely affect school performance and behavior. Because this population represents the majority of asthmatic children, one needs to use theophylline cautiously in this age group, monitor school performance closely, or seek other treatment modalities.  相似文献   
76.
A Maternal PKU camp provided education and social support for 25 young women with phenylketonuria (PKU). Questionnaires were administered and blood samples were collected on the first and last days of camp to evaluate the psychological and medical impact of the programme. Long-term outcome was assessed through telephone interviews 7 - 14 months later. Knowledge of maternal PKU and the maternal PKU diet increased significantly. There was a significant increase in campers' ratings of the degree to which others supported the use of birth control to prevent late-treated pregnancies, although campers' comfort with contraception did not change. Mean blood phenylalanine concentrations were significantly reduced by 37% during camp and by 20% at follow-up. Ninety-six per cent of campers remained in contact with other campers after the summer. At follow-up, one pregnancy was reported, in which metabolic control was achieved prior to conception. Overall, attitudes about treatment and perceptions about ability to cope with PKU did not change to a significant degree. It is suggested that camps may be most successful in changing both behaviour and attitudes if they actively involve the campers in food preparation, address the psychological meaning of food in our culture, and provide social support.  相似文献   
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This five-part review focuses on selected nonneoplastic diseases of the aorta and pulmonary trunk. Because many more diseases affect the aorta compared with the pulmonary trunk and right and left main pulmonary arteries, most of this review will be devoted to disorders of the aorta. Part II of this five-part series discusses complications of aortic dissection and aortic aneurysm.  相似文献   
79.
L R Rohr 《Cancer》1990,65(6):1460-1461
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80.
S Rohr  H Sadok  B Dai  C Meyer 《Journal de chirurgie》1992,129(6-7):320-323
Clinical and therapeutic characteristics of anorectal melanoma have been studied about 2 new cases. The initial symptoms were often misdiagnosed with hemorrhoids disease. This cancer carries a bad prognosis but the best treatment seems to be abdominoperineal resection (APR) when the thickness of the melanoma is under 3 mm. Over this limit, APR alone will not cure this disease. Curative treatment will probably involve a combined therapy with local and systemic therapies.  相似文献   
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