Category: A

A tumor of the argentaffin cells in the glands of the intestine. Argentaffinomas typically occur in the tip of the appendix and are among the commonest tumors of the small intestine. They may also occur in the rectum and other parts of the digestive tract and in the bronchial tree (bronchial carcinoid adenoma). Argentaffinomas sometimes…

Cells that stain readily with silver salts. Such cells occur, for example, in the crypts of Lieberkuhn in the intestine. A cell in the epithelium of the stomach, intestines, and appendix that secretes serotonin.  

The hippocampal formation of the cerebrum. The term is seldom used. Areas of the cerebral hemispheres that, along with the paleopallium, are sometimes called the rhinencephalon. The archipallium comprises the hippocampus, the dentate gyrus, the fasciolar gyrus, and the supracallosal gyrus (induseum griseum).  

A cavity that forms in the very early embryo as the result of gastrulation. In mem it forms a tubular cavity, the archenteric canal, which connects the amniotic cavity with the yolk sac.  

An operation in which the vermiform appendix is brought through the abdominal wall and opened in order to drain or decompress the intestine. It is now rarely performed, ‘ileostomy, cecostomy, or colostomy being preferred. Surgical opening and fixation of the appendix onto the skin. The opening is employed as a vent to an obstructed colon…

An antiserum containing antibodies against specific poisons in the venom of such an animal as a snake, spider, or scorpion. A serum created to treat snakebites and serve as an antidote to snake venom. It’s also known as antivenin.  

An antiserum, containing antibodies that suppress lymphocytic activity, prepared by injecting an animal with lymphocytes. ALS may be given to a patient to prevent the immune reaction that causes tissue rejection following transplantation of such organs as kidneys. Administration naturally also impairs other immunity mechanisms, making infection a serious hazard.  

The curved inner ridge of the pinna of the ear. The inner curved ridge of the external ear parallel to the helix.  

Describing impulses traveling the wrong way in a nerve fiber. This is rare but may happen in shingles, when the irritation caused by the virus in the spinal canal initiates impulses that travel outward in normally afferent nerves. The area of skin that the sensory nerves supply (usually a strip on the trunk) becomes painfully…

A disease that is transmissible from an animal to man, or vice versa, under natural conditions. Diseases that are found primarily in animals and sometimes affect man include anthrax, rabies, and leptospirosis. An infectious disease acquired by humans from vertebrate hosts of the causative agents.