(1) Destruction of red blood cells, bacteria, and other structures by a specific lysin, usually referred to by the structure destroyed (e.g., hemolysis, bacteriolysis, nephrolysis); may be due to a direct toxin or an immune mechanism, such as antibody reacting with antigen on the surface of a target cell, usually by binding and activation of a series of proteins in the blood with enzymatic activity (complement system). (2) Gradual subsidence of the symptoms of an acute disease, a form of the recovery process, as distinguished from crisis. [G. dissolution or loosening]