previous studies have revealed that the replacement of the c-2 ester group in phosphatidylcholine by the carbamyloxy function renders the resulting lipids , without affecting the properties of the liposomes , resistant to hydrolysis by phospholipase a2 ( gupta , c.m . bali , a . ( 1981 ) biochim . biophys , acta 663 , 506-515 ) .
C0020291
hydrolysis
C0031667
phospholipase a2