gland, Meibomian One of the small glands in the eyelids that make a lubricant called sebum that is discharged through tiny openings in the edges of the lids. The Meibomian glands can become inflamed, a condition termed meibomianitis or meibomitis. Chronic inflammation leads to cysts of the Meibomian glands, called chalazions. Also known as the…
gland, mammary One of the glands within the breast that secretes milk when prompted to do so by special hormones. The mammary glands become enlarged when they are engorged with milk. See also mastitis.
gland A group of cells that secrete a substance for use in the body. For example, the thyroid gland.
GIST Gastrointestinal stromal tumor.
gingivitis Gum disease with inflammation of the gums. The gums appear red and puffy and usually bleed during tooth-brushing or dental examination. Treatment involves improved cleaning. Antiseptic mouthwashes may also be recommended. See also acute membranous gingivitis; gum disease.
gingiva The gums.
Gilbert syndrome A common but harmless genetic condition in which UDP-glucuronosyltransferase, a liver enzyme that is essential to the disposal of bilirubin, is abnormal. Mutations in the same gene cause the Crigler-Najjar syndrome, which is a more severe and dangerous form of hyperbilirubinemia (high bilirubin in the blood). Also known as hyperbilirubinemia type 1.
gigantism, pituitary Extreme growth in height caused by oversecretion of growth hormone (somatotrophin) by the anterior pituitary gland. Other features of pituitary gigantism include thickening of the skin, enlargement of the bones, and elongation of the jaw and other areas. Pituitary gigantism may be caused by an adenoma of the pituitary gland, a benign tumor…
gigantism, focal Extreme growth of specific body parts, such as one arm, the tongue, or a combination of parts, as seen in Beckwith-Wiedemann syndrome or acromegaly. Focal gigantism may occur before or after the bones fuse. If it occurs afterward, it causes disfigurement. Surgery for mass reduction can help improve function, and other treatments may…
gigantism, eunuchoid Extremely tall stature due to the delayed onset of puberty that permits the continued growth of the long bones before their growing ends (epiphyses) fuse and growth stops.
gigantism 1 Extreme growth in height. Gigantism is usually associated with disorders of the pituitary gland, which secretes human growth hormone (somatotrophin) during childhood, before the bones fuse. 2 Extreme growth of specific body parts. See also gigantism, focal.
GIFT Gamete intrafallopian transfer.