The General Clinical Research Center is the focal point for clinical investigation at the University of Rochester. Twenty-four principal investigators with 56 projects have used the Center in the past year. Some of the current active protocols include the following studies: 1) carbohydrate and amino acid metabolism in cancer, 2) bile acid excretion in patients with jejunal bypass, 3) amino acid metabolism in patients with myopathy, 4) the relationship of energy expenditure to spontaneous food intake, 5) glucose homeostasis and ketogenesis as affected by sympathectomy, 6) studies of immunoglobulin metabolism in normal and diseased subjects, 7) trace metal metabolism in cirrhosis of the liver, 8) the relationship of fluoride metabolism to changes in bone, 9) study of the subgroups of lambda G globulin, 10) effects of potassium loading on renin excretion, and 11) factors influencing calcium excretion in hypercalcuric states.