2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/49513This research summarizes work done by myself (Nucl.Phys.{\bf A641} (1998)461), or in collaboration with R. M. Davidson (Phys.Lett.{\bf B348}(1995)163) and H. Weigel and L. Gamberg (Nucl.Phys.{\bf B560}(1999)xx). I will discuss several topics related with the computation of structure functions in the quark model in general and its perturbative evolution. In particular, I address this topic in the Nambu-Jona-Lasinio model of hadrons, where the nucleon is constructed as a soliton. I show that the handling of the regularization procedure is crucial in order to obtain exact scaling in the Bjorken limit and fulfillment of sum rules. I also include some problems concerning the general validity of quark model calculations.(LaTeX) 12 pages, 1 figure, Talk given at the Mini-Workshop "Hadrons as Solitons", Bled (Slovenia) July 9-17, 1999High Energy Physics - Phenomenologytext