TUMOUR-RELATED ENZYME ALTERATIONS IN THE CLEAR CELL TYPE OF HUMAN RENAL CELL CARCINOMA IDENTIFIED BY TWO-DIMENSIONAL GEL ELECTROPHORESIS Article Zimmermann Uwe, Protzel Chris, Scharf Christian, Klebingat Klaus-Jurgen, Walther Reinhard, Balabanov Stefan European Journal of Biochemistry. Vol. 268. 2001. P. 5977-5980