The Term 'Practical Progress' in Biomedical Sciences. A Structuralistic Approach to the Reconstruction of Epistemological Terms in Medicine. An attempt is made to elucidate the structure of the term 'practical progress' and to reconstruct it logically. The importance of discovery and confirmation of new regularities as well as of practical rules arising from them depends on their contribution to the solution of practical problems. The application of this structuralistic definition of 'practical progress' is demonstrated with an example from cardiac surgery (...) concerning the solution of the practical medical problem of myocardial protection during open heart surgery. (shrink)