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171.
Approximately 350 people, the inhabitants of two villages in the Fayum district of Egypt, were individually dusted with 50 g of powder containing 2.5 or 5.0 g permethrin kg?1. The inhabitants of a third village were left untreated as a control. Before treatment, approximately two-thirds of the population of all three villages were infested with bodylice. Fourteen days after treatment, the permethrin dust at the lower strength reduced the infestation by 98.8% and at the higher strength by 100%. The dust containing 5 g permethrin kg?1 maintained a high level of residual control (80.5%) for at least 91 days. The other gave a lower level of control at this time. Urine samples, taken from subjects in each of the treated villages before and after dusting, were analysed for permethrin metabolites. Results indicated that the maximum amount of permethrin absorbed, orally, through the skin, or by inhalation, was 39 μg kg?1 body weight, 24 h after treatment. No residue was found 30 days and 60 days after treatment. It was concluded that there was a very substantial safety margin when permethrin dusts were used on man for bodylice control.  相似文献   
172.
Populations of bodylice, Pediculus humanus humanus L., in Egypt have become resistant to DDT and BHC, but not to malathion. A single dust application of permethrin (1 % a.i.; cis: trans-ratio 25:75) rendered 98.9% of the treated population louse-free. Thirty-seven days after dusting 91.3% and at the end of the 98-day observation period 64.6% of the population were free of infestation; during the same period the proportion of infested individuals rose by 12.3% in a similar untreated village. Permethrin is ovicidal against bodylice, affects the population of the human flea, PulexirritansL., and ishighly effective against the rat flea, Xenopsyllacheopis(Rothsch.).  相似文献   
173.
174.
The aim of this study was to see the effect of ligation of the efferent ductules on the fine structure of typical and modified Sertoli cells in the rabbit. Testes from six control animals and from five operated animals were used in this study. It was found that ligation of the efferent ductules for 48 hours has no immediate effect on the structure of these cells and the cell-to-cell contacts remained unaffected.  相似文献   
175.
Acanthogyrus (Acanthosentis) tilapiae parasites were collected from the intestines of 300 fish belonging to three tilapia species sourced at the River Nile, Giza, Egypt. The proboscis of the parasite was characterized by three rows of hooks that curved towards the posterior of the body. The first row is supported by unmodified hooks. The parasite tegument has a series of alternative folds and a large number of pores. Sensory ganglia are located on the surface of the proboscis and body. Acanthogyrus (Acanthosentis) tilapiae provokes an aggressive host response indicated by hyperplasia of the intestinal goblet cells and focal eosinophil infiltrations. This acanthocephalan parasite shows a highly modified adaptation to its site of host infection.  相似文献   
176.
The aim of this study was to investigate effects of an organophosphate insecticide, diazinon (DI), on pancreas, and possible ameliorating role of vitamins E and C. We examined both in vivo and in vitro effects of DI on serum activities of alkaline phosphatase (ALP), γ-glutamyltransferase (GGT), amylase, and lipase enzymes. We also evaluated possible ameliorating effects of vitamins E and C combination against DI toxicity and blood levels of thiobarbituric acid reactive substances (TBARS) only in vivo. In vivo experimental groups were: control group, DI-treated group, and DI + vitamins E plus C-treated group. In vitro study groups were: control group and DI-treated group. The biochemical analyses were determined in in vitro experiments at both hour 0 and 24 while in in vivo experiments were determined only at hour 24. Lipase activity and TBARS level were found increased by DI in in vivo experiments while lipase activity was found decreased in in vitro experiments. Amylase and ALP activities were found decreased by DI in both in vivo and in vitro experiments. Also, the combination of vitamins E and C was found to partially improve these disorders. These results suggest that DI treatment causes pancreas damage via increasing oxidative stress in rats, and a combination vitamins E and C can reduce this lipoperoxidative effect.  相似文献   
177.
Tropical Animal Health and Production - During 2015 and 2016, from five different States of the Sudan, a total of 1000 cattle sera were purposively collected from many herds of apparently healthy...  相似文献   
178.
Good Agricultural Practices (GAPs) includes agricultural techniques which environmentally-conscious, is not harmful to human and animal health, target protection of natural resources, provide traceability and food security. With these kinds of production techniques, it is aimed at agricultural production which is socially viable, economically profitable and sustainable. In this study conducted under good agricultural practices, pesticide residues in apricot fruit were investigated. The experiment was set up to have 3 replications and 15 trees in each replicate, according to randomized trial design. From the trees included in the experiment, necessary samples were taken at the harvest time and analyzes were carried out. In this study, pesticide residue levels were determined in fruit extracts with high-precision analytical instruments such as LC-MS/MS and GC-MS. A total of 385 pesticide active substances were analyzed in LC-MS/MS and 101 pesticide active substances in GC-MS in fruit extracts. In this research carried out in 2014 and 2015, samples of both years were not found to be detectable to the tolerance values of Turkish Food Codex (TFC).  相似文献   
179.
The molluscicidal activity of Thuricide used as bacterial insecticide,Bacillus thuringiensis, againstBiomphalaria alexandrina andBulunus truncatus was tested.The obtained results indicate that Thuricide possess a mollus-cicidal activity against both snails species.B. truncatus was more sensitive to the action of Thuricide. However the slope function of the LC50 forB. alexandrina was significantly higher than that forB. truncatus. The mortality rate of exposedB. alexandrina increased by increasing the exposure time.  相似文献   
180.
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