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991.
JM Janusz PA Young JM Ridgeway MW Scherz K Enzweiler LI Wu L Gan R Darolia RS Matthews D Hennes DE Kellstein SA Green JL Tulich T Rosario-Jansen IJ Magrisso KR Wehmeyer DL Kuhlenbeck TH Eichhold RL Dobson SP Sirko RW Farmer 《Canadian Metallurgical Quarterly》1998,41(7):1112-1123
A series of 5-keto-substituted 7-tert-buty1-2,3-dihydro-3,3- dimethylbenzofurans (DHDMBFs) were prepared and evaluated as potential nonsteroidal antiinflammatory and analgesic agents. Interest in this class of compounds arose when a DHDMBF was found to be an active metabolite of the di-tert-butylphenol antiinflammatory agent tebufelone. We have now found that a variety of 5-keto-substituted DHDMBFs have good in vivo antiinflammatory and analgesic activity after oral administration. These compounds inhibit both cyclooxygenase (COX) and 5-lipoxygenase (5-LOX) in vitro. The cyclooxygenase inhibition was found to be selective for the cyclooxygenase-2 isoform, and this combination of COX-2/5-LOX inhibition may be responsible for the gastrointestinal safety of compounds such as 30. 相似文献
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SA Deetz 《The Journal of communication》1997,47(4):118-134
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A study of the effect of pasteurization on goats' milk took place in order to compare the effectiveness of two pasteurization processes (low and high pasteurization) by assessing the procedure microbiologically and biochemically. The results revealed that both pasteurization processes were effective, showing microbial destruction of approximately 100%. With regard to the determination of phosphatase activity to monitor pasteurization, data in both cases were higher than the limit established for a well pasteurized milk, according to the method used. Machine milked milk showing a lower microbial content nearly achieved the standard level by batch pasteurization, 0.75 μg phenol/ml, but 2.5 μg phenol/ml by the high temperature short time (HTST) method. Phosphatase activity levels of 1.8 and 4.3 μg phenol/ml were the mean values obtained for low and high pasteurization respectively. Our results lead to the conclusion that the batch method for pasteurization of goats' milk is more efficient in terms of total bacterial count than the HTST method. Furthermore, the technique used for the determination of phosphatase activity does not seem to be adequate for pasteurization control of goats' milk, since in very rare situations were we able to attain the limit established. 相似文献
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This paper describes changes in effluent quality occurring before and after an upgrade to the Bolivar Wastewater Treatment Plant in South Australia. Trickling filters (TF) were replaced with an activated sludge (AS) plant, prior to tertiary treatment using waste stabilisation ponds (WSPs). The water quality in the WSPs following the upgrade was significantly improved. Reductions in total and soluble BOD, COD, TKN, suspended solids and organic nitrogen were recorded and the predominant form of inorganic nitrogen changed from NH(4)-N to NO(2)/NO(3)-N. The reduction in ammonium and potentially toxic free ammonia removed a control upon the growth of zooplankton, which may have contributed to decreases in algal biomass in the final ponds and consequently lower dissolved oxygen. Additionally, changes in inorganic nitrogen speciation contributed to a slightly elevated pH which reduced numbers of faecal coliforms in WSPs. The AS pretreated influent recorded significantly lower inorganic molar N:P ratio (10-4:1) compared to those fed with TF effluent (17-13:1). Algae within the WSPs may now be nitrogen limited, a condition which may favour the growth of nitrogen-fixing cyanobacteria. The decrease in algal biomass and in dissolved oxygen levels may enhance sedimentary denitrification, further driving the system towards nitrogen limitation. 相似文献
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