retractor

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retractor

[ri′trak·tər]
(anatomy)
A muscle that draws a limb or other body part toward the body.
(medicine)
A clawlike instrument for holding tissues away from the surgical field.
References in periodicals archive ?
As far as the retractor muscles are concerned, Ariopelta capensis shows a relatively primitive condition, with the tentacular and pharyngeal retractors having a common origin at the posterior border of the pallial organs (Sirgel 1985), from where they extend anteriorly as a common trunk to opposite the centre of the pallium where the tentacle retractors of the left and right sides diverge.
For example, Oopelta differs by having an oxygnathous jaw; no caudal pore; the genital pore situated anteriorly near the tentacles; a penile structure; and the retractor muscles of the four tentacles being extremely shortened, each with its own origin.
3) in the area where the radial myofilament bundles, the divaricator muscle fibers, and the retractor muscles are connected at the base of the proboscis.
As the retractor muscles draw the proboscis through the rostral pore, the hook apparatus is compressed and the hooks are forced together.
Our observations of early larval development in trochoidean gastropods led us to hypothesize that the thin organic larval shell was insufficiently calcified at the onset of torsion and lacked the mechanical rigidity to antagonize contraction of the larval retractor muscles.
Two larval retractor muscles appeared to be well-developed, but only one was visible at a time in the rotating veliger, and for only a fraction of a second.