myofibril has definitions from the field of biology
1
[ noun ] (biology) one of many contractile filaments that make up a striated muscle fiber

Used in print

(J. W. C. Hagstrom et al., "Debilitating muscular...)

Such swollen fibers were deeply eosinophilic , contained a_few pyknotic nuclei , and showed loss of cross striations , obliteration of myofibrils , and prominent vacuolization .

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