1. Destruction of red blood cells, bacteria, and other structures by a specific lysin, usually referred to by the structure destroyed (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.
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