Acetogenin and prenylated flavonoids from Helminthostachys zeylanica with inhibitory activity on superoxide generation and elastase release by neutrophils - Huang, Y C; Hwang, T L; Yang, Y L; Wu, S H; Hsu, M H; Wang, J P; Chen, S C; Huang, L J; Liaw, C C (Planta Med, 2010)