title: Functional and fine structural heterogeneity of atrial cardiocytes.
mesh_terms: D002467:Cell Nucleus; D003594:Cytoplasmic Granules; D006056:Golgi Apparatus; D006321:Heart / Q000502:physiology*; D006325:Heart Atria / Q000166:cytology; D006329:Heart Conduction System / Q000166:cytology; D006801:Humans; D008854:Microscopy, Electron; D008931:Mitochondria, Muscle; D009206:Myocardium / Q000166:cytology*; D009210:Myofibrils; D012519:Sarcoplasmic Reticulum; D012849:Sinoatrial Node / Q000166:cytology