I band

(redirected from I disc)
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band

 [band]
1. a part, structure, or appliance that binds; for anatomical structures, see frenulum, tenia, trabecula, and vinculum.
2. in dentistry, a thin metal strip fitted around a tooth or its roots.
3. in histology, a zone of a myofibril of striated muscle.
4. in cytogenetics, a segment of a chromosome stained brighter or darker than the adjacent bands; used in identifying the chromosomes and in determining the exact extent of chromosomal abnormalities. Called Q-bands, G-bands, C-bands, T-bands, etc., according to the staining method used. See also layer, stria, and stripe.
A band the dark-staining zone of a sarcomere, whose center is traversed by the H band.
H band a pale zone sometimes seen traversing the center of the A band of a striated myofibril.
I band the band within a striated myofibril, seen as a light region under the light microscope and as a dark region under polarized light.
M band the narrow dark band in the center of the H band.
matrix band a cylindrical metal band with a special clamp or holder (the matrix retainer); it is filled with softened impression compound and seated over a tooth so that the compound flows into the prepared cavity and an impression of the tooth can be obtained. It is also used for placement and contouring of certain restorative materials.
orthodontic band a band fitted over a tooth to anchor an orthodontic fixed appliance.
Z band a thin membrane in a myofibril, seen on longitudinal section as a dark line in the center of the I band; the distance between Z bands delimits the sarcomeres of striated muscle.

I band

a light band on each side of the Z line of striated muscle fibers, comprising a region of the sarcomere where thin (actin) filaments are not overlapped by thick (myosin) filaments.
Synonym(s): I disc, isotropic disc

I band

Etymology: ME, band, flat strip
an isotropic band within a striated muscle fiber that appears dark in polarized light but light when stained. See also sarcomere. Compare A band.
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I band

I band

(band)
A light band on each side of the Z line of striated muscle fibers, comprising a region of the sarcomere where thin (actin) filaments are not overlapped by thick (myosin) filaments.

I band

the lighter colored cross-striation of muscle fibers; composed of filaments of actin.

Patient discussion about I band

Q. how bad can your headaches get the ones i get feel like a band around my head and my eyes ache.

A. Headache can be very painful; thankfully, headache chronic syndromes can be diagnosed and treated quite effectively. From your description it sounds like you have a well-known headache syndrome (maybe cluster headache). However, effective diagnosis and treatment aren't possible over the net, so I would suggest seeing a doctor in order to treat it.

You may read more here:
http://www.nlm.nih.gov/medlineplus/headache.html

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