Source:http://linkedlifedata.com/resource/umls/id/C0682620
NCI: A triangular-shaped unit of hepatic tissue, containing portions of three adjacent hepatic lobules with the portal canal in the center. The portal canal is composed of the portal vein, hepatic artery, bile ductile, and lymph vessel. There is a central vein at the apex of each peripheral corner. Blood flows from the portal vein and hepatic artery towards the central vein. Bile flows in the opposite direction, towards the portal canal.