myastheniagravis

myasthenia grav·is (grăvʹĭs) n.

A disease characterized by progressive fatigue and generalized weakness of the skeletal muscles, especially those of the face, neck, arms, and legs, caused by impaired transmission of nerve impulses following an autoimmune attack on acetylcholine receptors.

  [New Latin : myasthenia + Latin gravis, heavy, severe.]

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