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| a white, crystalline, water-insoluble solid, C14H9Cl5, usually derived from chloral by reaction with chlorobenzene in the presence of fuming sulfuric acid: used as an insecticide and as a scabicide and pediculicide: agricultural use prohibited in the U.S. |
| the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language). |
neurofibromatosis neu·ro·fi·bro·ma·to·sis (n&oobreve;r'ō-fī-brō'mə-tō'sĭs, ny&oobreve;r'-)
n.
A genetic disease characterized by pigmented skin lesions and multiple skin neurofibromas, and sometimes accompanied by physical deformity and a predisposition to brain tumors and various forms of cancer. Also called multiple neurofibroma, neuromatosis, Recklinghausen's disease, von Recklinghausen's disease.
neurofibromatosis (n r'ō-fī'brō-mə-tō'sĭs) Pronunciation Key
A genetic disease characterized by multiple benign tumors of peripheral nerves, called neurofibromas, and pigmented spots on the skin, sometimes accompanied by bone deformity and a predisposition to cancers, especially of the brain. |
neurofibromatosis
either of two hereditary disorders characterized by distinctive skin lesions and by benign, progressively enlarging tumours of the nervous system. Neurofibromatosis type 1, also known as von Recklinghausen's disease, is much the more common of the two disorders and is present in about one of every 3,000 live births. This type is characterized by the presence of cafe-au-lait (pale brown) spots on the skin and the formation of numerous benign soft tumours arising from the abnormal growth of nerves. The cafe-au-lait spots may be present at birth or infancy, and the neurofibromas and other tumours appear in late childhood or early adulthood; the latter can sometimes result in grossly disfiguring effects owing to their large size. The course of the disease is progressive in most cases. Neurofibromatosis type 2 is a much rarer inherited disease marked by tumours of the auditory canal in the ear and by small numbers of cafe-au-lait spots.
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