Letter: Procine aortic valves as replacements for human heart valves.
D000818:Animals; D001021:Aortic Valve / Q000637:transplantation*; D006349:Heart Valve Diseases / Q000601:surgery*; D006350:Heart Valve Prosthesis / Q000379:methods*; D006801:Humans; D013552:Swine; D014183:Transplantation, Heterologous