title: Proton magnetic resonance studies of conformation and flexibility of enkephalin peptides.
mesh_terms: D006860:Hydrogen Bonding; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D009038:Motion; D009419:Nerve Tissue Proteins; D009842:Oligopeptides; D011487:Protein Conformation; D011955:Receptors, Drug; D013329:Structure-Activity Relationship
chemical_list: D008024:Ligands; D009419:Nerve Tissue Proteins; D009842:Oligopeptides; D011955:Receptors, Drug