“…The most incisive experiments have involved orthotopic transplantation in which the recipient animal's own liver is excised and replaced with a homograft obtained from an unrelated mongrel animal 31,35,36,37,50,51,58 with a technique similar to that depicted in Figure 38. With this preparation there is no equivocation about the presence or absence of transplant viability, since survival provides incontrovertible proof of continuous homograft function.…”