The General Clinical Research Center of the Downstate Medical Center is now in its 07 year of operation. It is the central inpatient investigative unit for Pediatrics, Medicine, Obstetrics and Gynecology, and other clinical services. The scope of its operation ranges from studies of endocrine and metabolic abnormalities such as those found in osteogenesis imperfecta, dwarfism and hyperparathyroidism, to the use of intestinal adsorbents in the uremic states. Studies concerning the treatment of Paget's disease with calcitonin have continued and have been amplified by the addition of mithramycin as an adjunct to calcitonin therapy. The studies of the effects of calcitonin on postmenopausal osteoporosis have continued as have the investigations of the effect of this hormone on the bone lesions of multiple myeloma. Newer protocols activated this year are concerned with the use of prostaglandins as abortifacients and the feasibility of pre-natal venepuncture in fetuses with high risk of genetic abnormalities. It is proposed that these ongoing projects will be supplemented with studies concerning metabolic and immunologic changes during renal transplantation, as well as the immunologic effects of second and multiple transplants. For the first time during the current year, affiliated hospitals have been involved in active research on the unit. The Core Biochemistry Laboratory has maintained a high level of performance. The radioisotope laboratory is actively involved in radioimmunoassay procedures, particularly those concerned with parathormone, growth hormone and antibodies to calcitonin.