The introduction and maintenance of permanently indwelling catheters in the portal and hepatic veins of the sheep.
D000818:Animals; D002404:Catheterization; D005260:Female; D006503:Hepatic Veins; D008099:Liver / Q000502:physiology; D008722:Methods; D011169:Portal Vein; D011247:Pregnancy; D012756:Sheep