| musculus sphincter ani internus | <anatomy> A smooth muscle ring, formed by an increase of the circular fibres of the rectum, situated at the upper end of the anal canal, internal to the outer voluntary external anal sphincter. This sphincter is maximally-contracted when the rectal ampulla is at rest -empty or relaxed to accommodate a distending faecal mass. It is inhibited with filling of the ampulla, increased distension and peristalsis. Synonym: musculus sphincter ani internus, internal sphincter muscle of anus. (05 Mar 2000) |
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| musculus thyroarytenoideus internus | <anatomy, muscle> Origin, depression between the two laminae of thyroid cartilage; insertion, portions of vocal process of arytenoid; action, shortens and relaxes vocal cords; nerve supply, recurrent laryngeal; a number of the deeper and finer fibres of the thyroaryteroid muscle attached directly to the outer side of the true vocal cord. Synonym: musculus vocalis, musculus thyroarytenoideus internus, vocal muscle. (05 Mar 2000) |
| musculus vastus internus | <anatomy, muscle> Origin, medial lip of linea aspera; insertion, tibial tuberosity by way of common tendon of quadriceps femoris and ligamentum patellae; action, extends leg; nerve supply, femoral. Synonym: musculus vastus medialis, medial great muscle, medial vastus muscle, musculus vastus internus. (05 Mar 2000) |
| porus acusticus internus | The inner opening of the internal acoustic meatus on the posterior surface of the petrous part of the temporal bone. Synonym: porus acusticus internus, internal acoustic foramen, internal acoustic pore, auditory pore, internal auditory foramen, orifice of internal acoustic meatus. (05 Mar 2000) |
| nervus caroticus internus | <anatomy, nerve> The cephalic arterial ramus conveying postsynaptic sympathetic fibres from the superior cervical ganglion to the internal carotid artery to form the internal carotid plexus. Synonym: nervus caroticus internus. (05 Mar 2000) |
| sulcus spiralis internus | A concavity in the floor of the cochlear duct formed by the overhanging labium vestibulare. Synonym: sulcus spiralis internus. (05 Mar 2000) |
| internus | Synonym: internal. Origin: L. (05 Mar 2000) |
| obturator internus | <anatomy, muscle> Origin, pelvic surface of obturator membrane and margin of obturator foramen; insertion, passes out of pelvis through lesser sciatic foramen, in so doing, making a 90 |