title: [APUD system (problems of structural and functional organization, histogenesis and pathology)].
abstract: The aspects of structure and function of the APUD-system under normal and pathological conditions are analysed. New terms and concepts (apudocyte, apudoblast, apudogenesis, apudopathies) applicable to the APUD-system are introduced. It is suggested that some apudocytes originate from polypotential stem cells. The dysfunctions of the APUD-system (apudopathies) are described, their classification is suggested, and the role of apudocytes in the endogenous mechanisms of oncogenesis is analysed.
mesh_terms: D001078:APUD Cells / Q000166:cytology* / Q000473:pathology / Q000502:physiology; D001079:Apudoma / Q000145:classification / Q000503:physiopathology / Q000648:ultrastructure; D002454:Cell Differentiation; D004475:Ectoderm / Q000166:cytology; D004707:Endoderm / Q000166:cytology; D006651:Histocytochemistry; D006801:Humans; D008854:Microscopy, Electron; D009024:Morphogenesis
vernacular_title: APUD-sistema (voprosy strukturno-funktsional'noĭ organizatsii, gistogeneza, patologii).