Positional signalling by retinoic acid in the developing chick wing.
D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects*; D002642:Chick Embryo; D004305:Dose-Response Relationship, Drug; D004627:Embryonic Induction / Q000187:drug effects*; D014212:Tretinoin / Q000494:pharmacology*; D014921:Wings, Animal / Q000196:embryology*
D014212:Tretinoin