The U.S. National Cancer Institute does not currently endorse any
foreign translations of PDQ® and no such endorsement should be inferred
for the following translation.
括約筋
【原文】sphincter
弛緩または緊張して、体内の通路や開口部の開閉を行う環状の筋肉。例えば、肛門括約筋(肛門の開口部周囲)や幽門括約筋(胃の下側開口部)など。