sheath of Schwann


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Related to sheath of Schwann: neurilemma

sheath

 [shēth]
a tubular case or envelope.
arachnoid sheath the delicate membrane between the pial sheath and the dural sheath of the optic nerve.
carotid sheath a portion of the cervical fascia enclosing the carotid artery, internal jugular vein, vagus nerve, and sympathetic nerves supplying the head.
connective tissue sheath of Key and Retzius endoneurium.
crural sheath femoral sheath.
dural sheath the external investment of the optic nerve.
femoral sheath the fascial sheath of the femoral vessels.
Henle's sheath endoneurium.
lamellar sheath the perineurium.
medullary sheath myelin sheath.
myelin sheath (nerve sheath) the sheath surrounding the axon of myelinated nerve cells, consisting of concentric layers of myelin formed in the peripheral nervous system by the plasma membrane of Schwann cells, and in the central nervous system by the plasma membrane of oligodendrocytes. It is interrupted at intervals along the length of the axon by gaps known as nodes of Ranvier. Myelin is an electrical insulator that serves to speed the conduction of nerve impulses (see saltatory conduction).
pial sheath the innermost of the three sheaths of the optic nerve.
root sheath the epidermic layer of a hair follicle.
sheath of Schwann neurilemma.
synovial sheath synovial membrane lining the cavity of a bone through which a tendon moves.
tendon sheath a lubricated fibrous or synovial layer of tissue in which the tendon is housed and through which it moves.

neu·ri·lem·ma

(nū'ri-lem'ă), Despite etymologic arguments in favor of the alternative spellings neurilema and neurolemma, by far the most usual spelling is neurilemma.
A Schwann cell that enfolds one or more axons of the peripheral nervous system; in myelinated fibers, its plasma membrane forms the lamellae of myelin.
[neuri + G. lemma, husk]

sheath of Schwann

Etymology: Theodor Schwann, German anatomist, 1810-1882; AS, scaeth
a neurilemma sheath of nucleated cells enclosing a nerve fiber.

neu·ri·lem·ma

(nūr'i-lem'ă)
A cell that enfolds one or more axons of the peripheral nervous system; in myelinated fibers its plasma membrane forms the lamellae of myelin.
Synonym(s): neurolemma, sheath of Schwann.
[neuri- + G. lemma, husk]

Schwann,

Theodor, German histologist and physiologist, 1810-1882.
Schwann cell unit - a single Schwann cell and all of the axons lying in troughs indenting its surface.
Schwann cells - cells of ectodermal (neural crest) origin that compose a continuous envelope around each nerve fiber of peripheral nerves. Synonym(s): neurilemma cells
Schwann tumor
Schwann white substance - the lipid material present in the myelin sheath of nerve fibers; the medulla of bones and other organs.
schwannoma - Synonym(s): neurilemoma; neuroschwannoma
sheath of Schwann - a cell that enfolds one or more axons of the peripheral nervous system. Synonym(s): neurilemma

neu·ri·lem·ma

(nūr'i-lem'ă)
A cell that enfolds axons of the peripheral nervous system.
Synonym(s): sheath of Schwann.
[neuri- + G. lemma, husk]

sheath of Schwann,

n.pr See neurilemma.

sheath

1. a tubular case or envelope.
2. vernacular for prepuce.

adrenal pericapsular sheath
contains a plexus of large nerve trunks with numerous ganglion cells.
arachnoid sheath
the delicate membrane between the pial sheath and the dural sheath of the optic nerve.
carotid sheath
a portion of the cervical fascia enclosing the carotid artery, internal jugular vein, and vagus or vagosympathetic nerve.
carpal tendon s's
sheaths to the tendons of the muscles which course over the carpus.
crural sheath
femoral sheath.
dural sheath
the external investment of the optic nerve.
femoral sheath
the fascial sheath of the femoral vessels.
Henle's sheath
the endoneurium, especially the delicate continuation around the terminal branches of nerve fibers.
lamellar sheath
the perineurium.
medullary sheath, myelin sheath
the sheath surrounding the axon of myelinated nerve cells, consisting of concentric layers of myelin formed in the peripheral nervous system by the plasma membrane of Schwann cells, and in the central nervous system by the plasma membrane of oligodendrocytes. It is interrupted at intervals along the length of the axon by gaps known as nodes of Ranvier. Myelin is an electrical insulator that serves to speed the conduction of nerve impulses.
pial sheath
the innermost of the three sheaths of the optic nerve.
root sheath
the epidermal layer of a hair follicle.
sheath of Schwann
neurilemma.
synovial sheath
a synovial membrane sleeve through which a tendon moves; found commonly where a tendon passes over a joint.