Reversal of daunomycin and vinblastine resistance in multidrug-resistant P388 leukemia in vitro through enhanced cytotoxicity by triterpenoids. - Hasegawa,H.; Sung,J.H.; Matsumiya,S.; Uchiyama,M.; Inouye,Y.; Kasai,R.; Yamasaki,K. (Planta Med, 1995)