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N-acyloxyethylcarboxybetaine 형 양성계면활성제의 합성과 물성에 관한 연구
오양환,김용인,소희준,김병기 한국유화학회 1989 한국응용과학기술학회지 Vol.6 No.1
Five novel amphoteric surfactants of N-acyloxyethylcarboxybetaine series were synthesized via Schotten-Baumman reaction between five acid chlorides containing 10, 12, 14, 16 and 18 carbon atoms in their N-alkyl groups and dimethylaminoethanol to give the intermediate products, 2-dimethylaminoethylalkanoates(2). Quaternization of these products(2) was permitted to from 2-(acyloxyethyldimethylammonic)- acetates(3), whose structures were identified by elemental analysis, IR spectrophotometry and ^1Hnmr spectrometry. The yield of the final products was shown in the range of 77-80% based on the intrmediate products. The surface tension of the aqueous solution of (3) was measured, and the critical micelle concentrations (cmc) were shwn in the range of 2.1×10exp(-3) - 3.3×10exp(-4)mol/l, and the surface tension at cmc was 28-36 dyne/com. Cmc waw lowered gradually by the increment of the length of N-alkyl ester containing group. The isoelectric point was shown in the range of 4.44-5.20. It showed a tendency to lean toward the acidic site and its range was broadened as increase of the hydrophobic group length. A linear relationship between log cmc and the number of carbon atoms(N) in the hydrophobic alkyl chain was shown in the relative equation of log cmc=-1.75-0.1N, and the contribution rate of N on the standard free energy change in micellization, △(△G˚m)/△N, was calculated as-0.23 RT.
허연무,강문원,정규원,정희영,이홍균,김병기,김선무 대한감염학회 1981 감염 Vol.13 No.1
Pseudomembranous colitis(PMC) has been recognized as a severe gastrointestinal lesion associated with a variety of conditions. In recent years, the majority of cases have been ascribed to antimicrobial treatment. Clindamycin and lincomycin have been incriminated most often. Recent studies have shown that a toxin of Clostridium difficile is implicated as the cause of antibiotic-associated PMC. We experienced a female patient who developed diarrhea, abdominal pain and fever after having received clindamycin for 9 days. The PMC diagnosed by endoscopic biopsy. The PMC seemed to be self-limiting after olindamycin was stopped. Described here a case of PMC with some review of literatures.