Hypericum perforatum: Which Constituents may Induce Intestinal MDR1 and CYP3A4 mRNA Expression? - Gutmann, Heike; Poller, Birk; Büter, Karin Berger; Pfrunder, Arabelle; Schaffner, Willi; Drewe, Jürgen (Planta Medica, 2006)