| secondary X zone | An adrenocortical zone, situated in the inner zona fasciculata, that appears upon postpubertal gonadectomy in some male rodents, most notably the mouse; the development of this zone is believed to be stimulated by pituitary gonadotropins. (05 Mar 2000) |
|---|---|
| spectrometry, mass, secondary ion | A mass-spectrometric technique that is used for microscopic chemical analysis. A beam of primary ions with an energy of 5-20 kiloelectronvolts (kev) bombards a small spot on the surface of the sample under ultra-high vacuum conditions. Positive and negative secondary ions sputtered from the surface are analyzed in a mass spectrometer in regards to their mass-to-charge ratio. (12 Dec 1998) |
| dentin, secondary | Dentin formed and deposited in response to a normal or slightly abnormal stimulus, after the complete formation of the tooth. (12 Dec 1998) |
| immunization, secondary | Any immunization following a primary immunization and involving exposure to the same or a closely related antigen. (12 Dec 1998) |
| osteoarthropathy, secondary hypertrophic | Symmetrical osteitis of the four limbs, chiefly localised to the phalanges and the terminal epiphyses of the long bones of the forearm and leg, sometimes extending to the proximal ends of the limbs and the flat bones, and accompanied by dorsal kyphosis and joint involvement. It is often secondary to chronic conditions of the lungs and heart. (12 Dec 1998) |
| acinar cell tumour | A solid and cystic tumour of the pancreas, occurring in young women; tumour cells contain zymogen granules. (05 Mar 2000) |
| acute splenic tumour | Acute splenitis, enlargement, and softening of the spleen, usually due to bacteraemia or severe bacterial toxaemia. (05 Mar 2000) |
| adenoid tumour | Adenoma, or neoplasm with glandlike spaces. (05 Mar 2000) |
| adenomatoid odontogenic tumour | A benign epithelial odontogenic tumour appearing radiographically as a well-circumscribed radiolucent-radiopaque lesion usually surrounding the crown of an impacted tooth in an adolescent or young adult; characterised histologically by columnar cells organised in a duct-like configuration interspersed with spindle-shaped cells and amyloid-like deposition that gradually undergoes dystrophic calcification. Synonym: adenoameloblastoma, ameloblastic adenomatoid tumour. (05 Mar 2000) |
| adenomatoid tumour | A small, circumscribed, benign tumour of the genital tract, composed of small glandlike spaces lined by flattened or cuboidal mesothelium-like cells. (12 Dec 1998) |
| adipose tumour | <oncology, tumour> Clumps of fat cells. Literally, fat cancer. These are benign tumours that can form in the breast. (16 Dec 1997) |
| adrenal gland tumour | <oncology> A benign tumour or adenoma, that usually results in the excess production of adrenal gland hormones. (27 Sep 1997) |
| adrenal rest tumour | A rare, usually benign, ovarian tumour thought to be derived from embryonic rest cells of the adrenals. This tumour causes various degrees of masculinization. (12 Dec 1998) |
| ameloblastic adenomatoid tumour | A benign epithelial odontogenic tumour appearing radiographically as a well-circumscribed radiolucent-radiopaque lesion usually surrounding the crown of an impacted tooth in an adolescent or young adult; characterised histologically by columnar cells organised in a duct-like configuration interspersed with spindle-shaped cells and amyloid-like deposition that gradually undergoes dystrophic calcification. Synonym: adenoameloblastoma, ameloblastic adenomatoid tumour. (05 Mar 2000) |
| amyloid tumour | A localised form of amyloidosis in which amyloid occurs as masses or nodules beneath the skin or mucous membranes, e.g., in the larynx. Synonym: amyloid tumour, focal amyloidosis. (05 Mar 2000) |