This continuing series gathers and presents original research results on the leading edge of medicine and biology. Each article has been carefully selected in an attempt to present substantial topical data across a broad spectrum. Topics discussed include the adverse effects on reproduction of corticotropin; the actions of morphine and its related substances on primary-afferent neurons; magnetic resonance spectroscopy of bile in the diagnosis of chronic cholestatic diseases; cold-active enzymes and their potential use in biotechnology; midwifery practice and the classification and differential diagnosis of sclerosing cholangitis.