ABO blood group: The major human blood group system. The ABO type of a person depends on the presence or absence of two genes, A and B. These genes determine the configuration of the red blood cell surface. A person who has two A genes has red blood cells of type A. A person who has two B genes has red cells of type B. If the person has one A and one B gene, the red cells are type AB. If the person has neither the A nor the B gene, the red cells are type O. It is essential to match the ABO status of both donor and recipient in blood transfusions and organ transplants.
- Abortion, multiple
Abortion, multiple: Two or more miscarriages (spontaneous abortions) by a woman. Couples who have had multiple abortions have about a 5% chance that one member of the couple is carrying a chromosome translocation responsible for the miscarriages.
Abortion: In medicine, an abortion is the premature exit of the products of conception (the fetus, fetal membranes, and placenta) from the uterus. It is the loss of a pregnancy and does not refer to why that pregnancy was lost. A spontaneous abortion is the same as a miscarriage. The miscarriage of three or more […]
- Abortion, therapeutic
Abortion, therapeutic: An abortion that is brought about intentionally. Also called an artificial or induced abortion. As opposed to a spontaneous abortion (a miscarriage).
- A (adenine)
A (adenine): In genetics, A stands for adenine, one member of the A-T (adenine-thymine) base pair in DNA. The other base pair in DNA is G-C (guanine-cytosine). Each base pair forms a “rung of the DNA ladder.” A DNA nucleotide is made of a molecule of sugar, a molecule of phosphoric acid, and a molecule […]
- Abortive polio
Abortive polio: Abortive polio is a minor illness. It accounts for 80-90% of clinically apparent cases of polio infection, chiefly in young children. It does not involve the CNS. The usual symptoms are slight fever, malaise, headache, sore throat and vomiting which hit 3-5 days after exposure to the polio virus. Full recovery occurs in […]