Normal black kidney.

A black kidney has 3 major differential diagnoses: hemosiderosis, lipofuscin pigment and melanotic renal cell carcinoma. Excluding lipofuscin, the other 2 are accompanied by an abnormal renal function. We report on a 25-year-old man who intended to donate a kidney to his cousin.

Design of a microprocessor-controlled thermoregulated chamber for perfusing in vitro mammalian brain preparations.

A system is described that allows to perfuse in vitro isolated mammalian brain preparations obtained from adult guinea-pigs. It consists of a microprocessor controlled thermoregulation unit, a perfusion line and a perfusion/recording chamber. The main features of the thermoregulation unit include the ability to maintain stable temperatures between 10 and 37 degrees C and to precisely control the time course of the temperature changes.