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501.
The conversion of benzyl penicillin to 6-aminopenicillanic acid using an insoluble derivative of penicillin amidase 总被引:2,自引:0,他引:2
Penicillin amidase was extracted from Escherichia coli ATCC 9637, grown on phenylacetic, acid and glutamate, and purified by fractional ion with streptomycin sulphate, ammonium sulphate and polyethylene glycol, followed by chromatography on DEAE–cellulose. The purification factor was 100–200 × and the overall yield was about 115%. The enzyme was chemically attached to derivatives of cellulose and the kinetics of these insolubilized penicillin amidase preparations was investigated. 相似文献
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Wei He Gerrik F. Verhees Nikhil Bhagwat Ye Yang Dhananjaya S. Kulkarni Zane Lombardo Sudipta Lahiri Pritha Roy Jiaming Zhuo Brian Dang Andriana Snyder Shashank Shastry Michael Moezpoor Lilly Alocozy Kathy Gyehyun Lee Daniel Painter Ishita Mukerji Neil Hunter 《Developmental cell》2021,56(14):2073-2088.e3
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Katharina C. Harms Karl P. Kapitza Lisa Pahl Anh-Thu Tran Lilly Volkmann Dennis Buers Matthias Karst Manfred Stuhrmann Michael Bernateck 《Cytokine》2013,61(2):389-393
IntroductionThe etiology of multisomatoform disorder (MSD) is still largely unknown, but genetic factors seem to have an influence on pathogenesis. Pain is a major symptom of MSD and polymorphisms of different proinflammatory cytokines have been found associated with pain in former studies. Therefore, we presumed that cytokine polymorphisms could also be associated with MSD.Patients and methodsGroups of 148 MSD patients with pain as the leading clinical symptom and 149 age and gender matched healthy controls participated in this study. Nine cytokine polymorphisms were genotyped and statistically analyzed for associations with MSD.ResultsAllelic and genotypic associations were found for rs16944 (interleukin 1β), rs1800629 (tumor necrosis factor) and rs909253 (lymphotoxin α). After correcting for multiple testing, the association of rs1800629 with MSD remained significant. The rare A-allele was correlated with MSD (p = 0.007).DiscussionSince the common G-allele of rs1800629 (TNFα) occurs much more often in the control group than in the MSD group it is assumed to be protective. Being carrier of the A-allele seems to be a risk factor for MSD. 相似文献
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