| duodenal tumours | <radiology> 90% benign, in 2nd and 3rd portion: 50% malignant, in 4th portion: most malignant, of malignancies: 80-90% leading to adenocarcinoma Differential diagnosis: benign, tubular adenoma, leiomyoma, lipoma, hamartoma (Peutz-Jeghers), prolapsed antral polyp, Brunner's gland adenoma (really hypertrophy and hyperplasia), malignant, adenocarcinoma (80-90% of malignant lesions), villous adenoma (pre-malignant), carcinoid / isleT-cell tumour (12 Dec 1998) |
|---|---|
| infantile brain tumours | <radiology> Can be present at birth: choroid plexus papilloma, medulloblastoma, craniopharyngioma, ependymoma, astrocytoma, teratoma (12 Dec 1998) |
| odontogenic tumours | Neoplasms produced from tooth-forming tissues. (12 Dec 1998) |
| ovarian stromal tumours | <radiology> Age 20 - 50 yrs, 20% of all ovarian tumours, fibroma / fibrosarcoma, granulosa-theca cell tumour, with or without oestrogens most likely to be precocious puberty, endometrial hyperplasia/carcinoma, fibrocystic breast disease, Sertoli-Leydig cell tumour, aka: arrhenoblastoma, with or without androgens most likely to be masculinization, may be mixed type (12 Dec 1998) |
| ovarian tumours | <radiology> Before age 45 most likely to be 98% benign, 2/3 of cancers in ages 40 - 65 yrs see also: ovarian stromal tumours (12 Dec 1998) |
| lymphatic vessel tumours | Neoplasms composed of lymphoid tissue, a lattice work of reticular tissue the interspaces of which contain lymphocytes. The concept does not refer to neoplasms located in lymphatic vessels. (12 Dec 1998) |
| air plant | <botany> A plant deriving its sustenance from the air alone; an aerophyte. The "Florida moss" (Tillandsia), many tropical orchids, and most mosses and lichens are air plants. Those which are lodged upon trees, but not parasitic on them, are epiphytes. Source: Websters Dictionary (01 Mar 1998) |
| aquatic plant | <botany> Plants that must grow in water whether rooted in the mud or floating without anchorage, plants that must complete part or all of their life cycle in or near the water. (09 Oct 1997) |
| C3 plant | <plant biology> Plants that fix carbon dioxide in photosynthesis by the Calvin Benson cycle. The enzyme responsible for carbon dioxide fixation is RuDP carboxylase, whose products are compounds containing three carbon atoms. C3 plants are typical of temperate climates. Photorespiration in these plants is high. (07 Nov 1997) |
| C4 plant | <plant biology> Plants found principally in hot climates whose initial fixation of carbon dioxide in photosynthesis is by the HSK pathway. The enzyme responsible is PEP carboxylase, whose products contain four carbon atoms. Subsequently the carbon dioxide is released and re fixed by the Calvin Benson cycle. The presence of the HSK pathway permits efficient photosynthesis at high light intensities and low carbon dioxide concentrations. most species of this type have little or no photorespiration. (21 Mar 1998) |
| vascular plant | A plant which possesses a well-developed system of conducting tissue to transport water, mineral salts and sugars. (09 Oct 1997) |
| gene expression regulation, plant | Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in plants. (12 Dec 1998) |
| genes, plant | The hereditary material of plants. (12 Dec 1998) |
| genes, structural, plant | DNA sequences that code for RNA and for the proteins required for the enzymatic and structural function of plant cells. (12 Dec 1998) |
| genome, plant | The complete gene complement contained in a set of chromosomes in a plant. (12 Dec 1998) |