Medical terms - Letter P (page 15) | MedicalVocabulary.org

PKD

Short for phenylketonuria. See: Phenylketonuria.
PKU

See Maternal phenylketonuria.
PKU, maternal

A "sugar pill" or any dummy medication or treatment. For example, in a controlled clinical trial, one group may be given a real medication while another group is given a placebo that looks just like it in order to learn…
Placebo

Also called the placebo response. A remarkable phenomenon in which a placebo -- a fake treatment, an inactive substance like sugar, distilled water, or saline solution -- can sometimes improve a patient's condition…
Placebo effect

A positive medical response to taking a placebo, a sham medication as if it were an active medication. Up to one-third of patients given a placebo may respond with a reduction in symptoms, depending on the condition…
Placebo response

A positive medical response to taking a placebo, a sham medication as if it were an active medication. Up to one-third of patients given a placebo may respond with a reduction in symptoms, depending on the condition…
Placebo-controlled

A term used to describe a method of research in which an inactive substance (a placebo) is given to one group of participants, while the treatment (usually a drug or vaccine) being tested is given to another group. The…
Placenta

A temporary organ joining the mother and fetus, the placenta transfers oxygen and nutrients from the mother to the fetus, and permits the release of carbon dioxide and waste products from the fetus. It is roughly…
Placenta accreta

The abnormal adherence of the chorionic villi (vascular fingers of the chorion, a part of the placenta) to the myometrium (the muscle of the uterus), . Normally there is tissue intervening between the chorionic villi…
Placenta percreta

A placenta that invades the uterine wall. In placenta percreta, the vascular processes of the chorion (the chorionic villi), a fetal membrane that enters into the formation of the placenta, may invade the full thickness…
Placenta praevia

A placenta implanted near the outlet of the uterus, so that at the time of delivery the placenta precedes the baby. Placenta praevia can cause painless bleeding in the last third of pregnancy, and may be a reason for a…
Placenta, accessory

See: Accessory placenta
Placenta, low

Location of the placenta in the lower part of the uterus (womb) so that the placenta partially or completely covers the cervix. Also known as a placenta previa
Placenta, succenturiate

An extra placenta separate from the main placenta. In anatomy 'succenturiate' means accessory to an organ. In this case, a succenturiate placenta is an accessory placenta
Placenta, supernumerary

A succenturiate or accessory placenta
Placental

Pertaining to the placenta, the organ joining the mother and fetus during pregnancy
Placental BMP

See: MIC-1
Placental bone morphogenetic protein

See: MIC-1
Placental chorioangioma

A benign vascular (blood vessel) tumor of the placenta (afterbirth). Large chorioangiomas cause complications including excess amniotic fluid (polyhydramnios), maternal and fetal clotting problems (coagulopathies)…
Placental dystocia

Difficulty delivering the placenta (the afterbirth). Dystocia comes from the Greek 'dys' meaning 'difficult, painful, disordered, abnormal' + 'tokos' meaning 'birth.
Placental growth factor

A type of vascular endothelial growth factor. Placental growth factor is expressed not only in placental cells but also many nonplacental cells including endothelial cells (that line blood vessels). The gene that…
Placental stage of labor

The part of labor from the birth of the baby until the placenta (afterbirth) and fetal membranes are delivered. Also called the third stage of labor
Plague

Plague: The plague is an infectious disease due to a bacteria called Yersinia pestis. Y. pestis mainly infects rats and other rodents. Rodents are the prime reservoir for the bacteria. Fleas function as the prime…
Plague bacterium genome

All of the DNA (the genome) of the bacterium Yersinia pestis that causes the plague, consisting of four rings of DNA -- a large circular chromosome made up of 4,653,728 bases of DNA and three much smaller rings, or…
Plague genome

All of the DNA (the genome) of the bacterium Yersinia pestis that causes the plague, consisting of four rings of DNA -- a large circular chromosome made up of 4,653,728 bases of DNA and three much smaller rings, or…
Plague, black

In the 14th century the victims of the 'black plague' had bleeding below the skin (subcutaneous hemorrhage) which made darkened ('blackened') their bodies
Plague, bubonic

The most common form of the plague named for the characteristic buboes which are enlarged lymph nodes ('swollen glands') in the groin that are tender and painful. Lymph nodes may be similarly affected in the armpits…
Plague, fowl

The "Great Plague" that swept London in 1665 was probably not really the plague but rather typhus. The plague is a highly contagious, infectious, virulent, devastating disease due to a bacteria called Yersinia pestis…
Plague, Great

The 'Great Plague' that swept London in 1665 was probably not really the plague but rather typhus. The plague is a highly contagious, infectious, virulent, devastating disease due to a bacteria called Yersinia pestis…
Plague, sylvatic

Plague that is spread by ground squirrels and other wild rodents, for example, in the western portion of the United States. 'Sylvatic' means pertaining to the woods (sylvan)
Plan B

Brand name for a progestin-only emergency contraceptive designed to prevent pregnancy within 72 hours after a contraceptive accident or unprotected sex. However, early treatment is significantly more effective. Each 12…
Plano

In practical optics, a surface that has been worked flat
Plano-

Flat. A lens that is planoconvex is flat on one side and convex on the other
Plantar

Having to do with the sole of the foot. The plantar response (also known as the Babinski reflex) is elicited by stroking the sole. The plantar fascia is the 'bowstring-like' tissue stretching from the heel beneath the…
Plantar fasciitis

Inflammation of the plantar fascia (fasciitis), the 'bowstring-like' tissue in the sole of the foot stretching from the heel to the front of the foot. Plantar fasciitis (and heel spurs) may occur alone or be related to…
Plantar response

The plantar response, also known as the Babinski response, is an important neurologic examination based upon what the toes do when the sole (the plantar surface) of the foot is stroked. If the big toe goes up, that may…
Plantar warts

Warts: Warts that grow on the soles of the feet. Plantar warts are different from most other warts. They tend to be flat and cause the buildup of callus (that has to be peeled away before the plantar wart itself can be…
Plaque

1. An semi-hardened accumulation of substances from fluids that bathe an area. Examples include dental plaque and cholesterol plaque. > >Minerals form dental plaque around the teeth as a result of bacterial action on…
Plaque psoriasis

The most common form of psoriasis -- about 80% of people with psoriasis have this type. Plaque psoriasis can appear on any skin surface, although the knees, elbows, scalp, trunk and nails are the most common locations…
Plaque, skin

A plaque is a broad, raised area on the skin. Because it is raised, it can be felt (palpated). By definition, a skin plaque has a greater surface than its elevation above the skin surface: it is broader than it is high
Plasma

The liquid part of the blood and lymphatic fluid, which makes up about half of its volume. Plasma is devoid of cells and, unlike serum, has not clotted. Blood plasma contains antibodies and other proteins. It is taken…
Plasma cell

A type of white blood cell that produces and secretes antibodies. A plasma cell is a fully differentiated lymphocyte in the B-cell (not the T-cell) lineage. As with most cell types, plasma cells can mutate to give rise…
Plasma donation

The donation of sale of blood plasma for use in medical or other products. Unlike blood donors, most plasma 'donors' in the US are paid. The procedure is done in a walk-in facility, where whole blood is taken through an…
Plasma osmolarity

The osmolarity of blood plasma, which is a measure of the hydration status. The plasma osmolarity is sensitive to changes in hydration status during dehydration and rehydration. The normal plasma osmolarity is in the…
Plasmacytoma

Cancer of the plasma cells (white blood cells that produce antibodies) that may turn into multiple myeloma
Plasmapheresis

A procedure designed to deplete the body of blood plasma (the liquid part of the blood) without depleting the body of its blood cells. Whole blood is removed from the body, the plasma is separated from the cells, the…
Plasmid

A circle of DNA that is self-replicating (autonomously replicating) and distinct from the normal genome of bacteria. A plasmid contains genes that as a rule are not essential to the growth or survival of the cell. Some…
Plasmodium

The parasite guilty in the case of malaria (paludism). Plasmodium is a type of protozoa, a single-celled organism able to divide only within a host cell. The main types are: > >Plasmodium falciparum, the species which…
Plastic surgeon

A surgeon who specializes in reducing scarring or disfigurement that may occur as a result of accidents, birth defects, or treatment for diseases, such as melanoma. Many plastic surgeons also perform cosmetic surgery…
Plastic surgery

The field of surgery concerned with reducing scarring or disfigurement that may occur as a result of accidents, birth defects, or treatment for diseases, such as melanoma. Many plastic surgeons also perform cosmetic…