title: The self-nonself discrimination: a one- or two-signal mechanism?
mesh_terms: D000818:Animals; D000937:Antigen-Antibody Reactions; D000939:Epitopes; D006241:Haptens; D051379:Mice; D008954:Models, Biological; D010243:Paralysis; D011955:Receptors, Drug; D013601:T-Lymphocytes
chemical_list: D000939:Epitopes; D006241:Haptens; D011955:Receptors, Drug