Psychologic Care During Infancy and Childhood

A new milestone in the development of knowledge of metabolic processes was reached in 1934 when the late Rudolf Schoenheimer turned to the use of stable isotopic elements as a label in organic compounds. By this technic it became possible to follow the metabolic pathways of biologically important compounds; since although isotopic-containing substances are biochemically indistinguishable from their natural analogues, their distribution in the organism can be quantitatively determined by the micro methods available for measuring isotope concentrations. Administered substances, therefore, although entering the metabolic reactions of the body, can by their isotope content be rendered distinguishable from their naturally occurring analogues already present in the organism and thus may be followed in the course of their metabolic transformations. It is then possible to learn not only of the beginning and end of the metabolism story, but also of certain aspects of the intermediate reactions. This volume deals with a presentation and discussion of the major portion of the investigations conducted in Dr. Schoenheimer's laboratory by many colleagues under his direction and guidance. The volume contains three lectures which were prepared by Dr. Schoenheimer and presented, after his untimely death, by Dr. Hans T. Clarke under the Edward K. Dunham Lectureship at Harvard University. The lectures are entitled: "The Reaction of the Body Fats Investigated with Deuterium," "The State of the Body Proteins," and "The Role of Structural Elements in the Formation of Body Protein." Out of the investigations from Schoenheimer's laboratory there emerges a new and dynamic concept of metabolism. It is a concept of metabolic "regeneration," wherein the central idea is the continued release and uptake of chemical substances by tissues to and from a circulating metabolic "pool." Coincident with these cyclic processes there occur among the components of the pool multitudinous chemical reactions, of which only relatively few are concerned with elimination of waste products. The lectures are clearly and logically written and students of medicine and biology will find them stimulating and necessary reading for keeping abreast with recent advances in mammalian metabolism.