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Nerve Fibers, Myelinated MeSH Descriptor Data 2026


MeSH Heading
Nerve Fibers, Myelinated
Tree Number(s)
A08.675.542.512
A11.671.501.512
A11.671.514
Unique ID
D009413
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D009413
Scope Note
A class of nerve fibers as defined by their structure, specifically the nerve sheath arrangement. The AXONS of the myelinated nerve fibers are completely encased in a MYELIN SHEATH. They are fibers of relatively large and varied diameters. Their NEURAL CONDUCTION rates are faster than those of the unmyelinated nerve fibers (NERVE FIBERS, UNMYELINATED). Myelinated nerve fibers are present in somatic and autonomic nerves.
Entry Term(s)
A Fibers
B Fibers
NLM Classification #
WL 102.5
Previous Indexing
Neurons (1966-1971)
See Also
White Matter
Public MeSH Note
1974; for B FIBERS see AUTONOMIC FIBERS, PREGANGLIONIC 1976-2002
History Note
1974 (1972); for B FIBERS use AUTONOMIC FIBERS, PREGANGLIONIC 1976-2002
Date Introduced
1974/01/01
Last Updated
2022/07/14
Nerve Fibers, Myelinated Preferred
B Fibers Narrower
A Fibers Narrower
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