Anti-Inflammatory Activity of 20(S)-Protopanaxadiol: Enhanced Heme Oxygenase 1 Expression in RAW 264.7 Cells - Lee, Sung Hee; Seo, Geom Seog; Ko, Geonil; Kim, Jae Baek; Sohn, Dong Hwan (Planta Medica, 2005)