title: Electron microscopy of the heart conduction system of the dog.
mesh_terms: D000818:Animals; D004285:Dogs; D006329:Heart Conduction System / Q000166:cytology*; D008854:Microscopy, Electron; D009206:Myocardium / Q000166:cytology; D009210:Myofibrils / Q000166:cytology; D009411:Nerve Endings / Q000166:cytology; D009413:Nerve Fibers, Myelinated / Q000166:cytology; D009469:Neuromuscular Junction / Q000166:cytology; D012849:Sinoatrial Node / Q000166:cytology