Dictionary

sentinel lymph node See lymph node, sentinel.

sensory integration dysfunction A neurological disorder in which there is impaired perception or processing of sensory input to the brain. In sensory integration dysfunction, the processing of information from a number of different senses may be impaired, such as sight, hearing, touch, smell, taste, the sense of movement (vestibular system), and/or the positional sense (proprioception)….

sensory Relating to sensation, to the perception of a stimulus, to the voyage made by incoming nerve impulses from the sense organs to the nerve centers or to the senses themselves.

senile keratosis See keratosis, actinic.

seminal vesicle One of two structures that are about 5 cm long and are located behind the bladder and above the prostate gland. The seminal vesicles contribute fluid to the ejaculate.

semen analysis A laboratory test that measures the amount of semen a man produces and determines the number and quality of sperm in the semen sample. A semen analysis is usually one of the first tests done to help determine whether a man has a problem fathering a child (infertility).

semen The fluid that is released through the penis during orgasm. Semen is made up of fluid and sperm. The fluid comes from the prostate, seminal vesicles, and other sex glands. The sperm are manufactured in the testicles. The seminal fluid helps transport the sperm during orgasm. Seminal fluid contains sugar as an energy source…

sella turcica A depression in the base of the skull where the pituitary gland is situated. It was called the sella turcica (the Turkish saddle) because of its resemblance to a saddle used by the Turks which had supports in the front and back.

selenium deficiency See deficiency, selenium.

selenium An essential mineral that is a component of an antioxidant enzyme, glutathione reductase, that is key in tissue respiration. Food sources of selenium include seafoods; some meats, such as kidney and liver; and some grains and seeds. Too much selenium may cause reversible balding and changes in the nails, give a garlic odor to…

selective serotonin reuptake inhibitor See SSRI.

selective mutism An inability to speak in certain situations. See also apraxia; autism; elective mutism; mutism; social phobia.