Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «H»:
Hurricane: A regionally specific name for a strong tropical cyclone. The term hurricane applies in the North Atlantic Ocean, the Northeast Pacific Ocean east of the dateline, or the South Pacific Ocean east of 160E.
Other terms for the same type of storm, a strong tropical cyclone, include typhoon
Hurricane supplies kit
Hurricane supplies kit: A kit of supplies to have ready in the event of a hurricane (or other natural disaster).
You and your family can cope
best by preparing for disaster before it strikes. One way to prepare
is by assembling a Disaster Supplies Kit. Once disaster hits, you
won't have time to sh...
HUS: Hemolytic uremic syndrome....
Hyaline membrane disease
Hyaline membrane disease: A respiratory disease of the newborn, especially the premature infant, in which a membrane composed of proteins and dead cells lines the alveoli (the tiny air sacs in the lung), making gas exchange difficult or impossible. The word "hyaline" comes from the Greek word "hyal...
Hyaluronic acid: A viscous
slippery substance that lubricates the joints, maintains the shape of the eyeballs, and is a key component of connective tissue. On a
more technical level, hyaluric acid is an glycosaminoglycan (formerly called a
mucopolysaccharide), a long unbranched polysaccharide (co...
Hybrid: The word "hybrid" has a number of different biomedical meanings.
In transmission genetics, a hybrid is the result of a cross between two genetically dissimilar parents. The offspring of unlike parents. If the parents are sufficiently dissimilar, the hybrid may be sterile (for example, in the...
Hybridization, fluorescent in situ
Hybridization, fluorescent in situ: An important
molecular cytogenetic method for identifying chromosomes and parts of
chromosomes, deciphering chromosome rearrangements, and locating genes on chromosomes.
"Fluorescent" means emitting light that comes from a reaction within the emitter. "In situ"...
Hybridization, in situ
Hybridization, in situ: The use of a DNA or RNA probe to
detect the complementary sequence.
In situ hybridization is like all nucleic acid hybridization in being a technique in which single-stranded nucleic acids (DNA or RNA) are permitted to interact so that complexes, or hybrids, are formed by mol...
Hybridization, nucleic acid
Hybridization, nucleic acid: A laboratory technique in which single-stranded nucleic acids (DNA or RNA) are allowed to interact so that complexes called hybrids are formed by molecules with similar, complementary sequences.
Through nucleic acid hybridization, the degree of sequence identity between...
Hybridoma: A cell hybrid resulting from the fusion of a cancer
cell and a normal lymphocyte (a type of white blood cell). The hybridoma is immortal in
the laboratory and makes the same products as its parent cells forever. ...
Hydatid disease, alveolar
Hydatid disease, alveolar: A parasitic disease caused by the larval stage of a microscopic tapeworm called Echinococcus multilocularis. See: Alveolar hydatid disease....
Hydatidiform mole: A tumor that forms in the uterus as a mass of cysts resembling a bunch of grapes. Moles occur during the childbearing years. They do not spread outside of the uterus. However, a malignancy called choriocarcinoma may start from a hydatidiform mole.
In its early stages, a hydatidif...
Hydranencephaly: A condition in which the cerebral hemispheres of the brain are absent and replaced by sacs filled with cerebrospinal fluid. Usually the cerebellum and brainstem are formed normally.
An infant with hydranencephaly may appear normal at birth. The infant's head size and spontaneous r...
Hydrazine: Hydrazine sulfate, an alternative medicine that has been claimed to be a treatment for cancer. It has been used as a first-line agent in cancer therapy and as a treatment for cancer-related anorexia (loss of appetite) and cachexia (loss of muscle mass and body weight). The results from a ...
Hydrocarbon: An organic compound composed exclusively of hydrogen and carbon. All hydrocarbons have a carbon backbone with atoms of hydrogen attached to that backbone....