Serum oder Plasma. (Diagnostic proof of the DAO activity in serum and plasma.) In: Jarisch R, ed. Histamin-Intoleranz. EFTA00566747 Histamin and Seekrankheit. (Histamine intolerance. Histamine and motion sickness.) Stuttgart, Germany: Georg Thieme Verlag KG, 2004:8-17 (in German). 19. Jansen SC, van DM,