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Inter-laboratory validation studies were conducted in 6 laboratories to validate the biological method for determination of streptomycin in royal jelly. Streptomycin spiked at the level of 0.2 and 1.0 ppm was analyzed. Mean recoveries were 89 and 96%, reproducibility relative standard deviations (RSD(R)) were 15.0 and 14.0%, HORRAT(R) values were 0.7 and 0.9. Samples containing residues at the levels of 0.25 and 0.80 ppm were analyzed. Mean recoveries were 113 and 99%, RSD(R) were 15.0 and 10.4%, and HORRAT(R) values were 0.8 and 0.6. The determination limit was 0.1 ppm. These results show that this method has good performance.  相似文献   
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Renal ischemia/reperfusion (I/R) injury is one of the main causes of postoperative renal failure. Activated neutrophils are implicated in the development of I/R-induced renal failure. JTE-607 has been reported to be a potent inhibitor of the multiple inflammatory cytokines in the endotoxic shock mouse model and heart Langendorff perfusion model. In this study, we examined whether JTE-607 attenuates I/R-induced renal injury by reducing neutrophil activation. Male wistar rats were intravenously administered JTE-607 (JTE group, 30 mg/kg) or 5% mannitol (control group) 30 min before ischemia. JTE-607 reduced the I/R-induced increases in the serum concentrations of blood urea nitrogen and creatinine, and improved the histopathologic changes, including acute tubular necrosis. I/R-induced an increase in neutrophil activation, reflected by increases in renal cytokine-induced neutrophil chemoattractant (CINC)-1 and myeloperoxidase (MPO) concentrations which were significantly reduced by JTE-607. These findings indicate that JTE-607 attenuates I/R-induced acute renal injury, probably by inhibiting neutrophil activation. JTE-607 might be a novel therapeutic strategy for the protection of postoperative renal failure in surgery associated with renal ischemia as well as renal transplantation.  相似文献   
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M. Kanauchi    S. Watanabe    T. Tsukada    K. Atta    T. Kakuta    T. Koizumi 《Journal of food science》2008,73(6):C458-C463
ABSTRACT:  For food industry production processes and other uses, a mold that produces high levels of feruloyl esterase was obtained from laboratory mold collections and other sources. It was Aspergillus awamori G-2 that produces high levels of feruloyl esterase. The feruloyl esterase was purified using ion-exchange chromatography, size-exclusion chromatography, and HPLC chromatography. The enzyme was identified as a monomer protein using size-exclusion chromatography. Its optimum temperature and pH were, respectively, 40 °C and pH 5. Its activity was stable at pH 3 to 5. The enzyme was combined with xylan and starch, but it was absorbed by cellulose. The km of the feruloyl esterase was 0.0019% (0.01 mM). The enzyme showed stable activity at pH 3 and 50 °C, making this enzyme useful for food production.  相似文献   
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Landfill bioreactors (LBRs) with management of leachate and biogas have presented numerous advantages such as accelerated stabilization of solid wastes, reduced amount of leachate, and in situ leachate treatment. Such advantages have minimized environmental risks, have allowed extension of the useful life of the landfill site, and have fostered cost reduction. LBRs of three types have been developed using both anaerobic and aerobic modes: anaerobic, aerobic, and hybrid. Microorganisms in landfills cause various reactions related with organic fractions and heavy metals. Such functions have been stimulated in LBRs by recirculation of leachate with or without aeration. To date, most studies of microorganisms in LBRs have analyzed bacteria and archaea based on 16S rRNA genes and have analyzed fungi based on 18S rRNA genes from a taxonomical viewpoint. Indicator genes for specific functions in LBRs such as nitrification, denitrification, and methane production have also been monitored. The population dynamics of microorganisms in LBRs have been partially clarified, but the obtained data remain limited because of highly heterogeneous features of solid wastes inside LBRs. Systematic monitoring of microorganisms should be established to improve LBR performance.  相似文献   
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Total diet samples collected from seven regions throughout Japan in 2016 were analysed for polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like polychlorinated biphenyls (DL-PCBs), known collectively as dioxins. This led to estimates of the latest dietary intake of these contaminants for the general Japanese population (≥1 year old). The average daily intake of dioxins for a person weighing 50 kg, calculated at non-detected congener concentrations assumed to be equal to zero, was estimated to be 0.54 pg TEQ (toxic equivalents) kg?1 body weight (bw) day?1. This value is well below the tolerable daily intake of 4 pg TEQ kg?1 bw day?1 for dioxins in Japan. The average intake was highest from fish and shellfish, followed by meat and eggs. The TEQ contribution of the fish and shellfish group to the total dietary TEQs was significant (89%). The DL-PCBs accounted for about 67% of the dioxin intake. The latest dioxin intake level was compared with previous estimates from total diet study results obtained annually since 1998 to determine the time trends in the dietary intake of dioxins in Japan. Overall, the average dioxin intake appeared to be decreasing gradually during the period of study. The previous average intakes of dioxins ranged from 0.58 to 1.9 pg TEQ kg?1 bw day?1. The latest average intake was the lowest since 1998 and was about one-third of the average intake in 1998. This decreasing trend in the dietary intake of dioxins was mainly influenced by the decreased dioxin intakes from two food groups, fish and shellfish, and meat and eggs.  相似文献   
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目的:探讨绿茶饮料浓缩物缓解小鼠体力疲劳的作用。方法:240只清洁级雄性昆明小白鼠随机分为4组,分别以经口灌胃方式给予蒸馏水(对照组)、不同剂量绿茶饮料浓缩物[133mg/(kg·bw),665mg/(kg·bw),1995mg/(kg·bw)],每日1次,连续45d,进行负重游泳实验,测定血乳酸、血清尿素及肝糖原含量。结果:与对照组比,低、中剂量能够增加小鼠负重游泳时间(P<0.01);低剂量组可降低游泳后即刻的血乳酸水平(P<0.05),各剂量组均能降低游泳后20min的血乳酸水平(P<0.05);中剂量组能够增加小鼠肝糖原储备(P<0.05);各剂量组血清尿素水平没有明显变化(P>0.05)。结论:绿茶饮料浓缩物具有缓解小鼠体力疲劳的作用,以中剂量作用最强。  相似文献   
60.
The mussel Mytilus edulis and the cultured ark shell Anadara broughtonii in the southeast coasts of the Seto Inland Sea were contaminated with paralytic shellfish poison (PSP) following the appearance of the dinoflagellate Alexandrium tamiyavanichii in early December 1999. A. tamiyavanichii plankton collected around the Straits of Naruto on December 3, 1999 showed PSP toxicity, of which 83 mol% was accounted for by GTX2, GTX3 and GTX4. Its specific toxicity was 112.5 fmol/cell, and one MU was equivalent to 7,200 cells. Toxicity values at the beginning of toxification were 4.7 MU/g for the ark shell and 7.3 MU/g for the mussel. In the former, the value remained at almost 4 MU/g, resulting in prohibition of marketing for about two months. In the latter, it sharply decreased to less than 4 MU/g. These bivalves collected during the toxification period were dissected into five tissues, mantle, adductor muscle, hepatopancreas, gills and "others", and submitted to high-performance liquid chromatography (HPLC). The cultured ark shell accumulated GTX2, GTX3 and STX as major components and GTX1, GTX4, GTX5, neoSTX, dcSTX and PX1-3 (C1-C3) as minor ones. The amount of GTX3 decreased with time, while STX tended to increase. At the early stage of PSP toxification, toxins were accumulated in the gills and "others", most of which were quickly detoxified. On the other hand, PSP of the toxified mussel consisted of GTX4 as a main component, and GTX1, GTX2, GTX3, GTX5, STX and PX1-2 (C1-C2) as minor ones. Its toxin composition pattern was similar to that of the ingested causative plankton. Its total toxin decreased soon after disappearance of the dinoflagellate. During the decrease of toxicity, PSP tended to be retained in the hepatopancreas, resulting in accumulation of 50 mol% of total toxin.  相似文献   
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