SPECIFIC AIMS OF THIS PROJECT: 1) Liver blood flow: Radionuclide angiography, as a technique in this field, requires quantitation of its reproducibility. Advancing computer technology may ultimately permit actual quantitation of flow per unit volume. This is a long-term aim of this technique. Nutrient liver blood flow, as measured by galactose clearance, must be assessed in a larger number of patients. The extraction across the liver wall be quantitated by hepatic vein catheter studies. 2) Tyrosine metabolism. The mechanism of tyrosinemia still awaits final clarification. Measure of nutrient liver blood flow and quantitation of intrahepatic tyrosine, pyridoxal phosphate and alpha keto-glutarate levels will answer the mechanism if indeed the initial transamination is the primary defect. 3) Nutritional. We aim to evaluate altered amino acid solution, Hepatamine intravenously, and Hepatic-Aid orally, in malnourished encephalopathy prone cirrhotics. The questions to be answered are, first whether such solutions reduced the incidence of encephalopathy; and second, whether they are nutritionally competent.