UMEA UNIVERSITY MEDICAL DISSERTATIONS n. s. 83 539,096 FORSGREN STURE Differentiation of heart Purkinje fibres . An immuno— and enzyme histochemical and ultrastructural study . Umea 1982 8 s. 96, il .+ wkł. s . nlb . 2 Umea Univ . Medical Disserations n . s . 83 Akad. avhandling Univ . of Umea, Institute of Anatomy