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131.
Although health education has proven to be cost-effective in slowing the spread of enterobiasis, assessments of the effectiveness of health education to reduce infectious diseases specifically in children are rare. To evaluate the effect of health education on knowledge, preventative practices, and the prevalence of enterobiasis, 319 children from 16 classes were divided into experimental and control groups. Data were collected from May 2012 to March 2013. A 40-minute in-class talk was given once in the experimental group. There were significant differences over the time in the mean scores for children''s knowledge of Enterobius vermicularis infection in the intervention group compared to the control group (p<0.001). After the educational session, the score for knowledge about E. vermicularis infection increased from 60.2±2.32 to 92.7±1.19 in the experimental group; this gain was partially lost 3 months later, decreasing to 83.6±1.77 (p<0.001). Children''s enterobiasis infection prevention practice scores also increased, from 3.23±0.27 to 3.73±0.25, 1 week after the educational session, a gain that was partially lost at 3 months, decreasing to 3.46±0.36 (p<0.001). The overall E. vermicularis egg detection rate was 4.4%; the rates for each school ranged from 0% to 12.9% at screening. The infection rate at 3 months after the treatment sharply decreased from 12.3% to 0.8% in the experimental group, compared to a decrease from 8.5% to 3.7% in the control group during the same period. We recommend that health education on enterobiasis be provided to children to increase their knowledge about enterobiasis and improve prevention practices.  相似文献   
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Yolk proteins (YP1, YP2, and YP3) of the fall webworm, Hyphantria cunea, are of relatively low molecular weight. Yolk protein-2 (YP2) was purified from gel slices and by KBr density gradient ultracentrifugation followed by ion exchange chromatography. YP2 is composed of one subunit with a molecular weight of 35.5 kDa. YP2 contains neutral lipids (diacylglycerol and triacylglycerol) and phospholipids (phosphatidylcholine and phosphatidylethanolamine). The neutral lipids are largely composed of lauric acid and palmitoleic acid. YP2 contains relatively large amounts of glutamic acid and aspartic acid but small amounts of tyrosine, phenylalanine, and methionine. YP2 is a vitellin (Vn) synthesized by the fat body. Vitellogenin-2 (Vg2), the precursor of YP2, is present in very small amounts in the hemolymph. Lipophorin and storage protein also are found in the ovary of H. cunea, and these proteins do not immunologically cross-react with YP2. YP2 is detected in first instar larvae but completely disappears during the second instar, indicating that YP2 is intensively utilized during postembryonic development. Anti-YP2 antibodies cross-react with ovarial extracts of Bombyx mori but not with those of insects from other orders such as Cletus schmidti (Hemiptera), Lucilia illustris (Diptera), Anechura japonica (Dermaptera), Periplaneta americana (Dictyoptera), and Ducetia japonica (Orthoptera). © 1995 Wiley-Liss, Inc.  相似文献   
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Francisella tularensis, which causes tularemia, is an intracellular gram‐negative bacterium. F. tularensis has received significant attention in recent decades because of its history as a biological weapon. Thus, development of novel vaccines against tularemia has been an important goal. The attenuated F. tularensis strain ΔpdpC, in which the pathogenicity determinant protein C gene (pdpC) has been disrupted by TargeTron mutagenesis, was investigated as a potential vaccine candidate for tularemia in the present study. C57BL/6J mice immunized s.c. with 1 × 106 CFUs of ΔpdpC were challenged intranasally with 100× the median lethal dose (LD50) of a virulent SCHU P9 strain 21 days post immunization. Protection against this challenge was achieved in 38% of immunized C57BL/6J mice administered 100 LD50 of this strain. Conversely, all unimmunized mice succumbed to death 6 days post challenge. Survival rates were significantly higher in vaccinated than in unimmunized mice. In addition, ΔpdpC was passaged serially in mice to confirm its stable attenuation. Low bacterial loads persisted in mouse spleens during the first to tenth passages. No statistically significant changes in the number of CFUs were observed during in vivo passage of ΔpdpC. The inserted intron sequences for disrupting pdpC were completely maintained even after the tenth passage in mice. Considering the stable attenuation and intron sequences, it is suggested that ΔpdpC is a promising tularemia vaccine candidate.  相似文献   
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The biosorption and desorption of Cr, Cu and Al were carried out using brown marine algaeSargassum fluitans biomass, known as the good biosorbent of heavy metals. The content of alginate bound to light metals could be changed by physical and chemical pretreatment. The maximum uptake of Cr, Cu and Al was independent of the alginate content. The maximum uptake of Al was two times(mole basis) than those of Cu and Cr. The aluminum-alginate complex was found in the sorption solution of raw and protonated biomass. Most of Cu, Al and light metals sorbed in the biomass were eluted at pH 1.1. However, only 5 to 10% of Cr sorbed was eluted at pH 1.1. The stoichometric ion exchange between Cu and Ca ion was observed on Cu biosorption with Ca-loaded biomass. A part of Cr ion was bound to biomass as Cr(OH)2 + or Cr(OH)2+. Al was also bound to biomass as multi-valence ion and interfered with the desorbed Ca ion. The behavior of rawS. fluitans in ten consecutive sorption-desorption cycles has been investigated in a packed bed flow-through-column during a continuous removal of copper from a 35 mg/L aqueous solution at pH 5. The eluant used was a 1%(w/v) CaCl/HCl solution at pH3.  相似文献   
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