title: The ultrastructural features of the mammalian muscle spindle.
mesh_terms: D000818:Animals; D002467:Cell Nucleus; D004285:Dogs; D008854:Microscopy, Electron; D008856:Microscopy, Fluorescence; D008858:Microscopy, Phase-Contrast; D009046:Motor Neurons / Q000166:cytology; D009119:Muscle Contraction; D009470:Muscle Spindles / Q000166:cytology*; D009132:Muscles / Q000166:cytology / Q000294:innervation; D009210:Myofibrils; D009469:Neuromuscular Junction; D012519:Sarcoplasmic Reticulum; D012583:Schwann Cells; D013564:Sympathetic Nervous System / Q000166:cytology