root sheath


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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.

root sheath

one of the epidermic layers of the hair follicle: external root sheath is continuous with the stratum basale and stratum spinosum of the epidermis; internal root sheath comprises the cuticle of the internal roots, Huxley layer, and Henle layer.

root sheath

(rūt shēth)
One of the epidermic layers of the hair follicle: external root sheath is continuous with the stratum basale and stratum spinosum of the epidermis; internal root sheath comprises the cuticle of the internal roots, Huxley layer, and Henle layer.

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.
References in periodicals archive ?
Hair growth needs perifollicular vascularization, during which VEGF is upregulated in the outer root sheath (Yano et al.
Exogenous VEGF stimulates VEGFR-2mediated proliferation through phosphorylation of ERK in human outer root sheath cells and human hair follicle dermal papilla cells (Li et al.
VEGF upregulates VEGF receptor-2 on human outer root sheath cells and stimulates proliferation through ERK pathway.
VEGF165 modulates proliferation, adhesion, migration and differentiation of cultured human outer root sheath cells from central hair follicle epithelium through VEGFR-2 activation in vitro.
Structure of fiber, inner root sheath and outer root sheath cells in inactive follicles were either absent or disrupted.
On the ends of these fibres, a thick column of stained inner root sheath was carried by shed fibre forming a club like structure (Plate 1).
Several thin or sometimes two thick columns of stained inner root sheath were carried by shed fibres, forming a brush like structure (Plate 2).
A thin stepwise layer of stained inner root sheath was carried by shed fibres forming a step like structure (Plate 3).
The end of such shed fibres was reduced in diameter and a thin column of stained inner root sheath was carried by shed fibre (Plate 4).
This will show an enlarged segmental artery supplying an arteriovenous shunt on the outside of one of the dural root sheaths.