Dictionary

myeloid Referring to myelocytes, a type of white blood cell. Also known as myelogenous.

myeloproliferative disorder One of the malignant diseases leading to overproduction of certain bone marrow cells, including those that give rise to the red blood cells, the granulocytes, and the blood platelets. The myeloproliferative disorders include chronic myelogenous leukemia, chronic idiopathic myelofibrosis, essential thrombocythemia, chronic neutrophilic leukemia, chronic eosinophilic leukemia, and polycythemia vera.

myocardial infarction See heart attack.

myocarditis Inflammation of the heart muscle. Inflammation of heart muscle can be caused by viruses, medications, parasites, or underlying diseases. Treatment depends on the cause.

muscular Having to do with muscles or endowed with above-average muscle development. For example, the muscular system is all the muscles of the body, collectively.

muscular atrophy, post-polio Muscle wasting that occurs after the initial acute polio illness.

muscular dystrophy One of a group of genetic diseases characterized by progressive weakness and degeneration of the skeletal or voluntary muscles that control movement. Abbreviated MD. The muscles of the heart and some other involuntary muscles are also affected in some forms of MD, and a few forms involve other organs as well. The major…

muscular dystrophy, Becker A form of muscular dystrophy (MD) that is similar to Duchenne MD but milder. Patients with Becker MD produce a little of the key protein, dystrophin, whereas those with Duchenne make none. Progression of Becker MD is slower and symptoms tend to appear later than progression of Duchenne MD. Both Becker and…

muscular dystrophy, congenital A form of muscular dystrophy (MD) that is present at birth. Various types of congenital MD have been identified, each caused by a different genetic error. Congenital MD can affect males or females. Diagnosis is initially made via observation of general muscle weakness (hypotonia). See also dystrophy, myotonic.

muscular dystrophy, distal A rare type of muscular dystrophy (MD) that typically begins in adulthood and involves the muscles that are most distant from the midline, such as those of the hands and feet. Distal MD is inherited in an autosomal dominant manner and affects males and females. Also known as distal myopathy and distal…

muscular dystrophy, Duchenne The bestknown form of muscular dystrophy, which is due to mutation in a gene on the X chromosome that prevents the production of dystrophin, a normal protein in muscle. Abbreviated DMD. DMD affects boys and, very rarely, girls. DMD typically appears after two years of age with weakness in the pelvis and…

muscular dystrophy, Emery-Dreifuss A form of muscular dystrophy (MD) that begins in childhood or the teen years. It is a slowly progressing disorder that begins in the upper arms or upper legs. Contractures of the limbs are common, as are serious heart problems. Emery-Dreifuss MD is caused by mutation in the gene that encodes emerin…