Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «P»:
Phlebotomist: A person who draws blood. ...
Phlebotomus fever: See: Sandfly fever....
Phlebotomy: Obtaining blood from a vein. In the old days, this was done by incising (cutting) a vein and just letting the blood flow into a container. Today phlebotomy is done more neatly by puncturing a vein with a needle.
Phlebotomy may be done in order to obtain blood for diagnostic tests or to ...
Phobia: An unreasonable sort of fear that can cause
avoidance and panic. Phobias are a relatively common type of anxiety
For example, extreme fear of spiders is called
arachnophobia, and fear of being outside is known as agoraphobia.
Phobias can be treated with cognitive behavioral th...
Phobia, social: Excessive fear of embarrassment in social
situations that is extremely intrusive and can have debilitating
effects on personal and professional relationships. Phobias are
persistent, irrational fears of certain objects or situations. They
recognize that their fear may be excessiv...
Phocomelia: A congenital malformation (birth defect) in which the hands and feet are attached to abbreviated arms and legs. The word phocomelia combines phoco- (seal) and melia (limb) to designate a limb like a seal's flipper, one consequence of exposure of the developing fetus to thalidomide. Phoco...
Phonosurgery: Surgical procedures that maintain, restore, or enhance the human voice. Phonosurgery includes phonomicrosurgery (microsurgery of the vocal folds done through an endoscope), laryngoplastic phonosurgery (open-neck surgery that restructures the cartilaginous framework of the larynx and th...
Phosphatase, acid: Acid phosphatase is an enzyme that works under acid conditions and is made in the liver, spleen, bone marrow and the prostate gland.
Abnormally high serum levels of the enzyme may, for example, indicate prostate disease (infection, injury, or cancer)....
Phosphatase, alkaline: An enzyme made in the liver, bone, and the placenta and normally present in high concentrations in growing bone and in bile. Alkaline phosphatase is released into the blood during injury and during such normal activities as bone growth and pregnancy. It is measured in a routin...
Phosphate: A form of phosphoric acid. Calcium phosphate makes
bones and teeth hard. ...
Phospholipase: An enzyme that catalyzes the splitting of a phospholipid molecule by the addition of water. Also called a lecithinase.
There are a number of phospholipases. They are grouped on the basis of the specific chemical bond they split. The phospholipases include phospholipase A1 (PLA1), phos...
Phosphorus: An essential element in the diet and a major component of bone. Phosphorus is also found in the blood, muscles, nerves, and teeth. It is a component of adenosine triphosphate (ATP), the primary energy source in the body....
Phosphorylation: Phosphorylation is a biochemical process that involves the addition of phosphate to an organic compound.
Phosphorylation may, for instance, involve the addition of phosphate to glucose to produce glucose monophosphate. Or phosphorylation may, for example, involve the addition of pho...
Photic sneeze reflex
Photic sneeze reflex: A disorder characterized by nearly uncontrollable paroxysms of sneezing provoked in a reflex fashion by the sudden exposure of a dark-adapted subject to intensely bright light, usually to brilliant sunlight. The number of successive sneezes is usually 2 or 3, but can be up to a...
Photochemotherapy, psoralen: See: PUVA....