Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «V»:
Viral hemorrhagic fever
Viral hemorrhagic fever: A syndrome caused by infection with one of a number of viruses that can cause increased permeability of the blood vessels resulting in bleeding into the skin, internally, or from the mouth or other orifices. The bleeding is usually not life-threatening. Other signs and sympt...
Viral hepatitis: Viral hepatitis is liver inflammation caused by viruses.
Specific hepatitis viruses have been labeled A, B, C, D, E, F, and G. While other viruses
can also cause hepatitis, their primary target is not the liver....
Viral infection: Infection caused by the
presence of a virus in the body.
Depending on the virus and the person's state of health, various viruses can
infect almost any type of body tissue, from the brain to the skin. Viral
infections cannot be treated with antibiotics; in fact, in some cases ...
Viral myocarditis: See: Myocarditis, viral....
Viral particle: See: Virion....
Viremia: The presence of a virus in the blood. Viremia is analogous to bacteremia (the presence of bacteria in the blood) and parasitemia (the presence of a parasite in the blood). Viremia, bacteremia and parasitemia are all forms of sepsis (bloodstream infection).
The term "viremia" was compounded ...
Virginal membrane: A thin membrane which completely or partially occludes the vaginal opening. This fold of mucous membrane is usually present at birth at the orifice of the vagina. In medicine, it is called the vaginal membrane or the hymen. Hymen is a Greek word meaning "skin" or "membrane." The ...
Virilize: To cause a female to develop male characteristics such as a deepened voice, an increase in body and facial hair, a decrease in breast size, an enlargement of the clitoris, and "male-pattern" baldness.
Males produce hormones called androgens that cause them to develop typicall...
Virion: A complete virus particle with its DNA or RNA core and protein coat as it exists outside the cell. Also called a viral particle....
Virology: The study of viruses....
Virtual colonoscopy: A method for examining the colon by taking a series of x-rays and then using a computer to reconstruct three-dimensional pictures (a CT scan) of the interior surfaces of the colon from these x-rays. The pictures can be saved, manipulated to better viewing angles, and reviewed af...
Virulence: The ability of any
agent of infection to produce disease. The virulence of a
microorganism (such as a bacterium or virus) is a measure of the severity of the disease it is capable of causing.
The adjective virulent implies extremely noxious, damaging,
deleterious, disease-causing (p...
Virulent: Extremely noxious, damaging, deleterious, disease-causing (pathogenic). Marked by a rapid, severe, and malignant course. Poisonous, venomous.
The virulence of a microorganism is a measure of the severity of the disease it causes.
The word "virulent"
comes from the Latin "virulentus" fro...
Virus: A microorganism smaller than a bacteria,
which cannot grow or reproduce apart from a living cell. A virus
invades living cells and uses their chemical machinery to keep itself
alive and to replicate itself. It may reproduce with fidelity or with
errors (mutations)-this ability to mutate i...
Virus, attenuated: To attenuate is to weaken or to make (or become) thin. The word derives from a combination of the Latin prefix "ad-," meaning "to" or "toward," and "tenuis," meaning "thin."
The use of "attenuate" in medicine is not new. In the 16th century, eating dried figs was claimed to atten...