title: [ON THE SIGNIFICANCE OF THE INTENSITY OF THE 1ST TONE IN MITRAL DISEASE BEFORE AND AFTER OPERATION].
mesh_terms: D006348:Cardiac Surgical Procedures; D008946:Mitral Valve Stenosis; D010701:Phonocardiography; D013903:Thoracic Surgery
keywords: HEART SURGERY; MITRAL VALVE STENOSIS; PHONOCARDIOGRAPHY
vernacular_title: K VOPROSU O ZNACHENII INTENSIVNOSTI PERVOGO TONA PRI MITRAL'NOM POROKE DO I POSLE OPERATSII.