Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «P»:
Para: Any woman who has given birth once or more is termed a "para."
Note that, for a pregnancy to count as a "birth", it must go to at least 20 weeks' gestation (the mid-point of a full-term pregnancy) or yield an infant that weighs at least 500 grams, irrespective of whether the infant is liveborn...
Para- (prefix): A prefix with many meanings, including:
alongside of, beside, near, resembling, beyond, apart from, and
For example, the parathyroid glands are called "para-thyroid"
because they are adjacent to the thyroid. For another example,
paraumbilical means alongside the umbi...
Para-esophageal hiatal hernia
Para-esophageal hiatal hernia: Hiatal hernias are
categorized as being either para-esophageal or sliding.
Para-esophageal hernias are hernias in which the gastro-
esophageal junction stays where it belongs (attached at the
level of the diaphragm), but part of the stomach passes or
bulges into th...
Paracentesis: The removal of fluid from a body cavity using a needle, trocar, cannula, or other hollow instrument.
A paracentesis may be diagnostic or therapeutic as, for example, in ascites where there is free fluid in the abdominal (peritoneal) cavity. If the cause of the ascites is uncertain, di...
Paracentric chromosome inversion
Paracentric chromosome inversion: A basic type of
chromosome rearrangement. A segment that does not include the
centromere (and so is paracentric) has been snipped out of a
chromosome, turned through 180 degrees (inverted), and inserted right
back into its original location in chromosome. The fe...
Paradoxical embolism: Passage of a clot (thrombus) from a vein to an
artery. When clots in veins break off (embolize) , they travel first to the right side of
the heart and, normally, then to the lungs where they lodge. The lungs act as a filter to
prevent the clots from entering the arterial circul...
Paraesthesia: See: Paresthesia....
Paraffin dip: A treatment for the symptoms of joint and muscle conditions, such as arthritis, that consists of melted mineral wax derived from petroleum applied to a body area. Paraffin dips can be especially helpful in relieving the pain and stiffness of arthritis involving the small joints of the...
Paragonimiasis: Infection with the trematode (parasitic worm) Paragonimus. More than 10 species of trematodes (flukes) of the genus Paragonimus infect humans, the most common being Paragonimus westermani, the oriental lung fluke. While P. westermani occurs in the Far East, other species of Paragoni...
Paragonimus infection: See: Paragonimiasis....
Parainfectious: Occurring at the time of and in association with an acute infection or an episode of infection.
For example, transverse myelitis (a disorder of the spinal cord) can occur parainfectiously in association with a number of viral and bacterial illnesses....
Parainfluenza: A disease due to an acute respiratory infection caused by a parainfluenza virus. Parinfluenza occurs usually in children.
The clinical picture can range from a relatively mild influenza-like one to bronchitis, croup, and pneumonia.
Transmitted by aerosols, the virus is usually limit...
Paralysis: Loss of voluntary movement (motor
function). Paralysis that affects only one muscle or limb is partial
paralysis, also known as palsy; paralysis of all muscles is total
paralysis, as may occur in cases of botulism....
Paralysis, facial nerve
Paralysis, facial nerve: Loss of voluntary
movement of the muscles on one side of the face due to abnormal function of the facial nerve (the 7th
cranial nerve) which supplies those muscles. Facial nerve paralysis is also called Bell's palsy.
The cause of facial nerve paralysis is often not known,...
Paralysis, infantile (polio)
Paralysis, infantile (polio): Infantile paralysis is
an old synonym for poliomyelitis, an acute and sometimes devastating
viral disease. Man is the only natural host for poliovirus. The virus
enters the mouth and multiplies in lymphoid tissues in the pharynx
intestine. Small numbers of viru...