Adenosine deaminase (ADA) deficiency: A genetic (inherited) condition that results in a immune deficiency disorder called severe combined immunodeficiency disease. Adenosine deaminase is an enzyme that plays a key role in salvaging purine molecules.
ADA deficiency is of special interest in the history of genetics. The first successful instance of gene therapy in humans was carried out in 1990 by Drs. W. French Anderson, R. Michael Blaese and Kenneth W. Culver who infused genetically engineered blood cells to repair ADA deficiency.
- Adenosine thallium scan
Adenosine thallium scan: A method of examining the heart to obtain information about the blood supply to the heart muscle. Special cameras take a series of pictures of the heart. Radioactive sestamibi is injected into the bloodstream and serves as a tracer. The tracer attaches to certain cells and makes them visible to the special […]
- Adenosine triphosphate
Adenosine triphosphate: A nucleotide compound that is of critical importance for the storage of energy within cells and the synthesis of RNA. Abbreviated ATP.
Adenovirus: One of a group of viruses that can cause infections of the lung, stomach, intestine, and eyes. Symptoms resemble those of the common cold. There are no effective medications for treating adenovirus infection. Adenovirus infection typically does not cause death or permanent problems. More than40 types of adenoviruses have been recognized, all of which […]
- ADH (antidiuretic hormone)
ADH (antidiuretic hormone): A peptide molecule that is released by the pituitary gland at the base of the brain after being made nearby (in the hypothalamus). ADH has an antidiuretic action that prevents the production of dilute urine (and so is antidiuretic). A syndrome of inappropriate secretion of ADH may occur in association with oat-cell […]
- ADH secretion, inappropriate
ADH secretion, inappropriate: A condition that results in the inability to produce dilute urine and imbalance of fluids and electrolytes in the body, particularly lowering blood sodium. Symptoms include nausea, vomiting, muscle cramps, confusion, and convulsions. This syndrome may occur with oat-cell lung cancer, pancreatic cancer, prostate cancer, and Hodgkin’s disease, among other disorders. Also […]