This is an application for continuation grant of a General Clinical Research Center at the Hospital of the University of Pennsylvania. This Clinical Research Center is utilized for both in-patient and out-patient studies by members of the Departments of Pediatrics, Neurology, Medicine, Surgery, Radiology, Dermatology, and Obstetrics and Gynecology. Research protocols deal with a wide spectrum of diseases, mostly of a metabolic nature, which require specialized facilities for patient observation as well as dietary control. An associated clinical laboratory provides certain analyses which are required specifically by study patients and which are not otherwise generally available in the institution.