The Much-Holzmann reaction was an early attempt at a serological test for the diagnosis of dementia praecox, an early-twentieth century psychiatric diagnosis superseded by schizophrenia. The originatiors of this test, Much and Holzmann of Eppendorf, posited that sera from patients suffering from dementia praecox protected red blood cells from cobra venom hemolysis.
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Much-Holzmann reaction Wikipedia(Text) CC BY-SA