Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «P»:
Pneumosilicosis: See: Silicosis....
Pneumothorax: Free air in the chest outside the lung.
Pneumothorax can occur spontaneously ("out of the blue", with or without underlying lung disease), follow a fractured
rib, occur in the wake of chest surgery, or be deliberately induced in order to collapse
the lung. Smoking has been shown to in...
PNL (percutaneous nephrolithotripsy)
PNL (percutaneous nephrolithotripsy): A technique for removing large and/or dense stones and staghorn stones.
PNL is done via a port created by puncturing the kidney through the skin and enlarging the access port to 1 cm (about 3/8 inch) in diameter. There is no surgical incision.
PNL is done unde...
PNS (peripheral nervous system)
PNS (peripheral nervous
system): That portion of the nervous system that is outside the brain and spinal cord.
The peripheral nervous system (PNS) is one of the two
major divisions of the nervous system. The other is the central nervous system
(CNS) which is made up of the brain and spinal cord.
Podiatrist: A podiatrist is a physician that
specializes in the evaluation and treatment of diseases of the foot.
The modern specialty of Podiatric Medicine and Surgery requires a
minimum of three years of college education and completion of the
M.C.A.T. (Medical College Admission Test) before ...
Podocyte: A cell with branching tentacle-shaped extensions that constitutes the barrier through which blood is filtered in the glomerulus of the kidney. From the Greek pod- (foot) + -cyte (cell)....
Poikiloderma: Extra pigmentation of the skin demonstrating a variety of shades and associated with widened capillaries (telangiectasia) in the affected area....
Poikiloderma atrophicans with cataract
Poikiloderma atrophicans with cataract: Better known as
the Rothmund-Thomson syndrome, this is an hereditary disease
characterized by progressive degeneration (atrophy), scarring and
abnormal pigmentation of the skin together with stunting of growth,
baldness, cataracts, depressed nasal bridge...
Poikiloderma congenita: Better known as the Rothmund-Thomson syndrome, this is an hereditary disease characterized by progressive degeneration (atrophy), scarring and abnormal pigmentation of the skin together with stunting of growth, baldness, cataracts, depressed nasal bridge, and malformations o...
Point mutation: A single nucleotide base change in the DNA. A point mutation may consist of the loss of a nucleotide, the insertion of an additional nucleotide, or the substitution of one nucleotide for another.
The first point mutation discovered in humans involved the substitution of one nucleot...
Point, McBurney's: McBurney's point is the most tender area of the abdomen of patients in the early stage of appendicitis.
McBurney's point is named after the 19th-century New York surgeon Charles McBurney (1845-1913) who was the leading authority in his day on the diagnosis and treatment of appe...
Poison: Any substance that
can cause severe distress or death if ingested, breathed in, or absorbed through
the skin. Many substances that normally cause no problems, including water and most vitamins, can be
poisonous if taken in too large of a quantity. Poison treatment depends on the
Poison Control Center
Poison Control Center: Special information
centers set up to inform Americans about how to respond to
potential poisoning. These centers maintain a database of
poisons and appropriate emergency treatment. The Poison
Control Center in your area should be listed with other
community service numbe...
Poison ivy: Skin inflammation resulting from contact
with oils from the poison ivy vine. Chemicals produced by this vine
cause an immune reaction, producing redness, itching, and blistering
of the skin.
Poison ivy (Rhus radicans) is a woody shrub or vine. It is found throughout the US and many ot...
Poison oak: Poison oak is a form of "contact
dermatitis" or inflammation of the skin resulting from chemicals produced from the
poison oak plant contacting the skin. The chemicals cause an immune reaction producing
redness, itching and blistering of the skin. ...