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Medical Definition of Hyrtl's sphincter
1. A band, generally incomplete, of circular muscular fibres in the rectum about 10 cm above the anus (upper rectal ampulla). See: Nelaton's sphincter. (05 Mar 2000)
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1. A band, generally incomplete, of circular muscular fibres in the rectum about 10 cm above the anus (upper rectal ampulla). See: Nelaton's sphincter. (05 Mar 2000)