Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «M»:
Mask of pregnancy
Mask of pregnancy: Muddy-brown pigmentation on the cheeks or elsewhere on the face that develops in about half of all women during pregnancy. Some women also develop it outside pregnancy, as do some women on hormone therapy. The pigmentation is worsened by ultraviolet (UV) light, which tends to dar...
Mask, oxygen: A mask that covers the mouth and
nose, and is hooked up to an oxygen tank. It delivers
oxygen directly to the patient. Oxygen can also be delivered directly through a nasal catheter, a tube that divides into two smaller tubes that go into the nostrils.
Oxygen is a colorless, odorless...
Masklike face: An expressionless face with little or no sense of animation, a face more like a mask than a real face.
A masklike face is seen in a number of disorders including Parkinson's disease and myotonic dystrophy.
Also called masklike facies....
Masochism: Pleasure from one's own pain. Masochism
is considered a sexual disorder, or paraphilia. Named after the
19th-century Austrian writer Leopold von Sacher-Masoch (masoch-ism).
Mass spectrometry: An instrument used to identify chemicals in a substance by their mass and charge. Mass spectrometers are instruments that essentially weigh molecules. A mass spectrometer also can measure how much of a compound is present in a mixture. Also known as mass spectroscopy. See also: Ta...
MASS syndrome: A heritable disorder of connective
tissue characterized by involvement of the mitral valve, aorta, skeleton, and skin. Hence, the acronym MASS (Mitral valve, Aorta, Skeleton, Skin).
The MASS syndrome is due to a mutation in FBN1, the fibrillin 1 gene. The same gene as is mutated in ...
Massage: The manipulation of muscle and connective tissue to enhance the function of those tissues and promote relaxation and well-being. Therapeutic massage can ease tension and reduce pain.
Massage can be a part of physical therapy or practiced on
its own. It can also be highly effective for red...
Massage therapist: A person who practices
therapeutic massage. In many US states, massage therapists
can be licensed after completing a specified training
program. Licensed therapists may practice independently or
in a medical setting....
Masseter: The muscle that raises the lower jaw. ...
Mast cell: A connective tissue cell whose normal function is unknown but which is frequently injured in allergic reactions, releasing chemicals including histamine that are very irritating and cause itching, swelling, and fluid leakage from cells. These allergic chemicals may also cause muscle spasm...
Mast cell tumor
Mast cell tumor: A mastocytoma....
Mast syndrome: An autosomal recessive form of hereditary spastic paraplegia with dementia first described in the Old Order Amish. The disease usually surfaces in early adulthood and is slowly progressive. The Mast syndrome gene is in chromosome 15q22.31 Its protein product is called maspardin....
Mastalgia: Pain in the breast or mammary gland. From the Greek masto-,
breast + algos, pain....
Mastectomy: A general term for removal of the
breast, usually to remove cancerous tissue. The operation can be done
in a hospital or in an outpatient clinic, depending on how extensive
it needs to be. It takes from two to three hours, with three to five
weeks for full recovery. Drainage shunts a...
Mastectomy, double: Removal of both breasts....