We have made computer-assisted reconstructions from serial ultrathin sections from equine skeletal muscle fibers. ... Switzerland): STEPone: An Interactive Program for Manual Morphometry Since powerful microcomputers have become available at ... System requirements are an IBM PC. PC XT. PC AT or compatible, 256 kilobytes of RAM. one floppy drive station and DOS 2.1 or higher. STEPone is aimed at the user who has an understanding of basic stereological techniques.