title: On the substructures of secretory granules of the chick beta islet cell.
mesh_terms: D000818:Animals; D002645:Chickens / Q000033:anatomy & histology*; D003594:Cytoplasmic Granules; D007515:Islets of Langerhans / Q000166:cytology* / Q000378:metabolism; D008854:Microscopy, Electron