Dictionary

fingers, six See hexadactyly.

fingernail A covering for the tip of the finger that is produced by living skin cells in the finger. A fingernail consists of several parts, including the nail plate (the visible part of the nail), the nail bed (the skin beneath the nail plate), the cuticle (the tissue that overlaps the plate and rims the…

fine needle aspiration The use of a thin needle to withdraw material from the body for analysis. For example, when a nodule is felt in the thyroid, fine needle aspiration may be done to remove a tissue sample that can be examined to determine whether the nodule is benign or malignant. The aspirated material is…

filovirus A virus in the family filoviridae that causes hemorrhagic fever. Filoviruses have singlestranded RNA as their genetic material. Ebola virus and the Marburg virus are both filoviruses.

film, PA An X-ray picture in which the beams pass from back to front (posteroanterior). See also film, AP.

film, lateral An X-ray picture taken from the side.

film, AP An X-ray picture in which the beams pass from front to back (anteroposterior). See also film, PA.

film Slang shortening of X-ray film.

filariasis A parasitic disease caused by the African eye worm, a microscopic thread-like worm. The adult worms can only live in the human lymph system. Lymphatic filariasis affects people in the tropics and sub-tropics of Asia, Africa, the Western Pacific, and parts of Central and South America. The disease spreads from person to person by…

fifth disease A mild disease occurring typically in children that is caused by parvovirus B-19. The characteristic symptoms of fifth disease include lowgrade fever, fatigue, a “slapped cheeks” rash, and a rash over the whole body. Transmission is by droplets in the air (respiratory secretions) or through blood. Some children with immunodeficiency (such as those…

fièvre boutonneuse See typhus, African tick.

fibula The smaller of the two bones in the lower leg. The end of the fibula forms the bony prominence of the outer ankle.