Role of P-glycoprotein in limiting the brain penetration of glabridin, an active isoflavan from the root of Glycyrrhiza glabra - Yu, X Y; Lin, S G; Zhou, Z W; Chen, X; Liang, J; Yu, X Q; Chowbay, B; Wen, J Y; Duan, W; Chan, E; Li, X T; Cao, J; Li, C G; Xue, C C; Zhou, S F (Pharm Res, 2007)