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421.
The effect of exposure to crude oil contaminated diet on the blood antioxidant defence system, lipid peroxidation, lipid profile as well as possible protective roles of vitamins E and C were studied in rabbits. Oxidative stress induction by crude oil was indicated by significantly (P < 0.05) increased lipid peroxidation and a non-significant (P < 0.05) decrease in superoxide dismutase and catalase activities. A similar pattern was also detected in the lipid profile: total cholesterol and LDL-cholesterol insignificantly (P < 0.05) increased while HDL-cholesterol and triglyceride significantly decreased relative to rabbits fed normal diet. The reciprocal relationship between HDL-cholesterol and LDL-cholesterol in addition to compromised antioxidant enzymes could predispose exposed animals to coronary heart disease. However, pre-treatment of the diet with vitamins C and E exhibited a protective role on the toxic effect of crude oil on lipid profile, lipid peroxidation as well as antioxidant enzymes. The order of protection was vitamin E + C > vitamin E > vitamin C. These observations seemed to suggest that the protective role of vitamins C and E is synergistic. The protective role of the vitamins is probably time-dependent as significant (P < 0.05) restoration of lipid profile as well as antioxidant enzymes activities to control values was effected after four weeks of exposure. It is therefore suggested that toxic effect of crude oil may be reduced by dietary supplementation of vitamins C and E.  相似文献   
422.
黑龙江省森林病虫害防治工作存在的问题及对策   总被引:2,自引:0,他引:2  
简述了黑龙江省森林病虫害防治工作存在的主要问题,分析了制约我省森林病虫害防治的主要因素,提出了病虫害防治的具体方法及对策.  相似文献   
423.
ABSTRACT: Rainwater harvesting is receiving increased attention worldwide as an alternative source of drinking water. Although collected rainwater is typically consumed without any type of disinfection, the microbial quality of this type of water source can be poor. Around the world, consumers of collected and stored rainwater may be at considerable risk to a variety of infectious diseases. This review presents studies attributing specific risks of diseases to the consumption of contaminated rainwater. Diseases attributed to the consumption of untreated rainwater include bacterial diarrheas due to Salmonella and Campylobacter, bacterial pneumonia due to Legionella, botulism due to Clostridium, tissue helminths, and protozoal diarrheas from Giardia and Cryptosporidium. Simple indicator systems such as fecal coliform measurements may prove to be inadequate for determining microbial risks associated with consumption of water from rainwater catchment systems.  相似文献   
424.
The damage effects of oxy free radical and fulvic acid on cultivated chicken embryo chondrocytes were studied. The results show that the growrth of chondrocytes is inhibited and the morphology of the cells altered. The collagen synthesizing capability of the damaged cell changes somewhat. A noteworthy change of the type of collagen synthesized by the abnormal cells was observed by CMC-chromatography and amino acid analysis. The results indicated that the abnonml cells tend to synthesize type I instead of type II collagen, which is synthesized and secreted by the intact chondrocyte.  相似文献   
425.
A study on "selenium-health" database in China   总被引:1,自引:0,他引:1  
A database for "Se and health" has been established using DATA-TRIEVE data management system on a VAX-11/780 computer. Over 5000 pieces of information including 300 kinds of samples from 28 provinces in China were stored. The information relates to endemk diseases such as Keshan disease, Kaschin-Beck disease, Se-poison disease, cancers, heart disease and so on. The database can be accessed through keywords: samples, province, county, analytical method and the Se-content values can be obtained in tabulated form. The output includes primary statistics of the retrieved data sets. A multi-variable statistic program package featuring in pattern recognition is attached to the system.  相似文献   
426.
An investigation on the organic degradation products and selenium in the pathogenesis of Kaschin-Beck disease was carried out. The results demonstrated that the organic degradation products existed in food and drinking water were the pathogens of the KBD; their leading pathological process of cells would be "membrane injury" due to peroxide. As GSH-Px is a selenium contained enzyme, therefore insufficient selenium would be one of the most important conditions to cause KBD.  相似文献   
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Air pollution causes an estimated 200,000 deaths per year in the United States alone. Older adults are at greater risk of mortality caused by air pollution. Here we quantify the number of older adult facilities in Los Angeles County who are exposed to high levels of traffic derived air pollution, and propose policy solutions to reduce pollution exposure to this vulnerable subgroup. Distances between 20,362 intersections and 858 elder care facilities were estimated, and roads or highways within 500 of facilities were used to estimate traffic volume exposure. Of the 858 facilities, 54 were located near at least one major roadway, defined as a traffic volume over 100,000 cars per day. These 54 facilities house approximately 6000 older adults. Following standards established for schools, we recommend legislation mandating the placement of new elder care facilities a minimum of 500 ft from major roadways in order to reduce unnecessary mortality risk from pollution exposure.  相似文献   
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