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Cephalosporin reaction with protein amino groups is fundamental to cephalosporin allergy. Cephalothin and cefazolin reaction kinetics with epsilon-aminocaproic acid, B-alanine, and glycine in aqueous solution were investigated. All reactions were conducted at 35 degrees and 0.5 ionic strength and were followed by ion-exchange high-pressure liquid chromatography. The aminolysis rate constants can be expressed as terms representing uncatlyzed or water-catalyzed amine reaction, self-assited nucleophilic reaction, and hydroxide-ion-catalayzed nucleophilic amine attack on the beta-lactam moiety. Cephalothin and cefazolin react with amines as readily as penicillin G. The UV spectra of several cephalothin-glycine reaction products were recorded, and their possible structures are discussed. 相似文献
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K Yasumoto K Tadera H Tsuji H Mitsuda 《Journal of nutritional science and vitaminology》1975,21(2):117-127
A simple system for semi-automatic analysis of pyridoxal, pyridoxine and pyridoxamine has been developed using diazide of 5-chloroaniline 2,4-disulfonyl chloride as a color-producing reagent in combination with desoxypyridoxine as an internal standard. It employs Aminex A-5 column, 10x0.6? cm, as an adsorbent. Adsorbates were eluted successively with 3 discrete phosphate buffers (0.4 N Na+). The effluent is mixed continuously with capillary streams of the diazide reagent and of sodium acetate. The mixture, maintained at 65 degrees C in a heating bath, then passes through a spiral of Teflon tubing with a residence time of 2 min. Characteristic orange colored products formed by a diazo coupling reaction are continuously monitored at 440 nm in a flow photometer. The individual peaks on the recorded chromatogram are manually integrated by a conventional HW method. The elution position and recovery of desoxypyridoxine permits correction for sensitivity changes or mechanical losses which might occur during a series of analyses. The analyzer system described allow quantitation from 2 to 25 mug of pyridoxal, pyridoxine and pyridoxamine in a single sample within 2 hr and with a precision of 100 +/- 4%. It is also found suitable as a routine procedure for the analysis of varied biological samples. 相似文献
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T. Koyanagi T. Takamatsu M. Terashima N. Nonomura I. Tsuji 《International urology and nephrology》1978,10(4):267-274
A case of Fraley's syndrome in a Japanese woman was reported. This is believed to be the first case involved in a complete duplex kidney. 相似文献