Category: At-At

Pertaining to the atria, the upper chambers of the heart, as in atrial fibrillation and atrial septal defect.

The plural of atrium.

Congenital absence or closure of the major bile ducts, the ducts that drain bile from the liver. Biliary atresia results in a progressive inflammatory process which may lead to cirrhosis of the liver. The infant looks normal at birth but develops jaundice after the age of 2 to 3 weeks with yellowing of the eyes and skin, light-colored stools and dark…

Congenital absence of the normal valvular opening from the left ventricle of the heart into the aorta. “Atresia” here refers to the absence of a normal opening.

Congenital absence of an opening at the bottom end of the intestinal tract. Also called imperforate anus. Occurs in about 1 in 5,000 births. It is corrected by surgery. Atresia refers to the absence of a normal opening.

Absence of a normal opening, or failure of a structure to be tubular. Atresia can affect many structures in the body. For example, esophageal atresia is a birth defect in which part of the esophagus is not hollow, and with anal atresia, there is no hole at the bottom end of the intestine.

1. Adenosine triphosphate.  2. Acute thrombocytopenic purpura.

The genetic tendency to develop the classic allergic diseases — atopic dermatitis, allergic rhinitis (hay fever), and asthma. Atopy involves the capacity to produce IgE in response to common environmental proteins such as house dustmite, grass pollen, and food allergens. From the Greek atopos meaning out of place.

A skin disease characterized by areas of severe itching, redness, scaling, and loss of the surface of the skin. Atopic dermatitis is the most common of the many types of eczema. Atopic dermatitis is frequently associated with other allergic disorders, especially asthma and hay fever. A defect of the immune system within the skin has been detected in patients who have atopic dermatitis, but the reason for…

A predisposition toward developing certain allergic hypersensitivity reactions. Atopy may have a hereditary component, although contact with the allergen must occur before the hypersensitivity reaction can develop.