title: A D-periodic narrow filament in collagen.
mesh_terms: D000818:Animals; D003094:Collagen / Q000302:isolation & purification*; D008854:Microscopy, Electron; D055095:Optics and Photonics; D011487:Protein Conformation; D051381:Rats; D013710:Tendons / Q000032:analysis
chemical_list: D003094:Collagen