5 aminolevulinate synthase 6 Antineoplastic Agents 6 Busulfan 6 Chick Embryo 6 Cyclophosphamide 6 Fluorouracil 6 Liver 6 Porphyrins 6 antineoplastic agent 6 article 6 busulfan 6 chick embryo 6 cyclophosphamide 6 fluorouracil 6 liver 6 nonhuman 6 porphyrin 6 5-Aminolevulinate Synthetase 4 Animal 4 Heme 4 Support, Non-U.S. Gov't 4 animal 4 chicken 4 drug effect 4 heme 4 metabolism 4 porphyrin synthesis 4 Alkylating Agents 2 Altretamine 2 Animalia 2