| balloon cell | An unusually large degenerated cell with pale-staining vacuolated or reticulated cytoplasm, as in viral hepatitis or in degenerated epidermal cell's in herpes zoster, a large form of nevus cell with abundant nonstaining cytoplasm, formed by vacular degeneration of melanosomes. (05 Mar 2000) |
|---|---|
| balloon cell nevus | A nevus in which many of the cells are large, with clear cytoplasm. (05 Mar 2000) |
| band cell | <pathology> Immature neutrophils released from the bone marrow reserve in response to acute demand. (18 Nov 1997) |
| b and t cell count | A test that measures the respective quantities of B lymphocytes and T lymphocytes. This test is often performed in the analysis of an immune deficiency disorder. Normal values include: 68 to 75% of total lymphocytes are T lymphocytes and 10 to 20% are B lymphocytes. Increased T-cell counts can indicate infectious mononucleosis, acute lymphocytic leukaemia or multiple myeloma. Increased B lymphocytes can indicate chronic lymphocytic leukaemia, multiple myeloma, Waldenstrom's macroglobulinaemia or Di George syndrome. Decreased T-cells may indicate congenital T-cell deficiency, Wiskott-Aldrich syndrome or AIDS. Decreased B-cells may indicate acute lymphocytic leukaemia or a congenital immunoglobulin deficiency disorder. (27 Sep 1997) |
| basal cell | <pathology> General term for relatively undifferentiated cells in an epithelial sheet that give rise to more specialised cells act as stem cells). In the stratified squamous epithelium of mammalian skin the basal cells of the epidermis (stratum basale) give rise by an unequal division to another basal cell and to cells that progress through the spinous, granular and horny layers, becoming progressively more keratinised, the outermost being shed as squames. In olfactory mucosa the basal cells give rise to olfactory and sustentacular cells. In the epithelium of epididymis their function is unclear, but they probably serve as stem cells. (13 Nov 1997) |
| basal cell adenoma | <tumour> A benign tumour of major or minor salivary glands or other organs composed of small cells showing peripheral palisading. (05 Mar 2000) |
| basal cell carcinoma | <oncology, tumour> The most common form of skin cancer. A malignant growth of epidermal tissue, specifically basal cells. most common in the fair-skinned on sun-exposed areas (especially the face). (15 Nov 1997) |
| basal cell epithelioma | <oncology, tumour> The most common form of skin cancer. A malignant growth of epidermal tissue, specifically basal cells. most common in the fair-skinned on sun-exposed areas (especially the face). (15 Nov 1997) |
| basal cell hyperplasia | Increase in the number of cells in an epithelium resembling the basal cells. (05 Mar 2000) |
| basal cell layer | The deepest layer of the epidermis, composed of dividing stem cells and anchoring cells. Synonym: basal cell layer, columnar layer, germinative layer, palisade layer, stratum basale, stratum cylindricum, stratum germinativum. (05 Mar 2000) |
| basal cell nevus | A hereditary disease noted in infancy or adolescence, characterised by lesions of the eyelids, nose, cheeks, neck, and axillae, appearing as uneroded flesh-coloured papules, some becoming pedunculated, and histologically indistinguishable from basal cell epithelioma; also noted are punctate keratotic lesions of the palms and soles; the lesions usually remain benign, but in some cases ulceration and invasion occur and are evidence of malignant change; autosomal dominant inheritance. (05 Mar 2000) |
| basal cell nevus syndrome | <syndrome> An inherited group of defects which involve abnormalities of the skin, eyes, nervous system, endocrine, glands and bones. The condition is characterised by an unusual facial appearance and a predisposition for skin cancer. (27 Sep 1997) |
| basal cell papilloma | A benign skin lesion resulting from excessive growth of the top layer of skin cells. It usually is found in persons over 30 years old and may be few or numerous. (12 Dec 1998) |
| basaloid cell | A cell, usually of the epidermis, resembling a basal cell. (05 Mar 2000) |
| basal squamous cell carcinoma | <tumour> A carcinoma of the skin which in structure and behaviour is considered transitional between basal cell and squamous cell carcinoma The term should not be used for the much more common keratotic variety of basal cell carcinoma, in which the tumour cells are of basal type but which contains small foci of abrupt keratinization. Synonym: basal squamous cell carcinoma. (05 Mar 2000) |