Jugular VeinsSubclavian VeinVeinsCatheterization, Central VenousBrachiocephalic VeinsCatheters, IndwellingPolytetrafluoroethyleneArteriovenous Shunt, SurgicalHyperplasiaGraft Occlusion, VascularBlood Vessel ProsthesisModels, AnimalCarotid ArteriesRabbitsSwineDogsSaphenous VeinPortal VeinFemoral VeinVaricose VeinsCerebral VeinsTime FactorsPulmonary VeinsPhlebographyCranial SinusesVenous ValvesFusobacterium necrophorum