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 (fī′brəl, fĭb′rəl)
1. A small slender fiber or filament.
2. Anatomy A threadlike fiber or filament, such as a myofibril or neurofibril, that is a constituent of a cell or larger structure.
3. A long strand of proteins that are aggregated together in a beta-sheet structure; an amyloid fibril.

[New Latin fibrilla, diminutive of Latin fibra, fiber.]

fi′bril·lar (-lər), fi′bril·lar′y (-lĕr′ē) adj.
fi′bril·lose′ (-lōs′) adj.


1. exhibiting fibrillation
2. another word for fibrilar


, fibrillary
a. fibrilar, rel. a una fibra;
___ astrocyteastrocito ___;
___ contractionscontracciones ___ -es.
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References in periodicals archive ?
However, focal expression of S100, c-KIT, glial fibrillary acidic protein (GFAP), and vimentin can be seen in some tumors (Figure 7, A and B).
Tumor cells are encircled with abundant fibrillary chondromyxoid ground substance in hemorrhagic background.
Expression of glial fibrillary acidic protein was weak, and the presence o f Ki-67 protein demonstrated a low proliferation rate (figure 2,C).
The following commercially available antibodies were used: polyclonal antibodies against S100 protein and monoclonal antibodies against epithelial membrane antigen, vimentin, synaptophysin, glial fibrillary acidic protein (GFAP), CD34, p53, CD3, CD20, AE1/AE3, MIB-1 (all Ventana Medical Systems, Tucson, Arizona), CAM 5.
stem Histo- Post op Cause of Sex resection Involvement pathology Survival Death 4/F Subtotal + fibrillary 11 days B.
2, p63, smooth muscle actin, and glial fibrillary acid protein yielded negative results.
The cells are fusiform with elongated fibrillary cytoplasm, and their buckled to spindled nuclei exhibit little atypia.
Microscopic examination revealed spindle cells with fibrillary cytoplasm arranged in interlacing fascicles & exhibiting nuclear palisading with mild to moderate nuclear pleomorphism.
17) Negative reactivity for S100, h-caldesmon, CD34, and glial fibrillary acidic protein help in the differential diagnosis with other types of sarcomas (Table).
10) PLGAmay stain with glial fibrillary acidic protein (GFAP), but this is usually less consistent than is GFAP staining of pleomorphic adenomas.
Immunohistochemical marker [IHC] Glial Fibrillary Acidic Protein [GFAP] confirmed the diagnosis[Figure 3].
Previously published works limited to small case series and case reports used only neurilemmal markers (eg, Leu-7, glial fibrillary acid protein, myelinbasic protein, peripherin), S100 protein, and factor XIIIa (a marker of perineurial fibroblasts) to differentiate these 2 entities.