Investigation of glucose-dependent insulinotropic polypeptide-(1-42) and glucagon-like peptide-1-(7-36) degradation in vitro by dipeptidyl peptidase IV using matrix-assisted laser desorption/ionization-time of flight mass spectrometry. A novel kinetic approach. - Pauly,R.P.; Rosche,F.; Wermann,M.; McIntosh,C.H.; Pederson,R.A.; Demuth,H.U. (J Biol Chem, 1996)