| PTA | Primitive trigeminal artery |
|---|---|
| PHSC | primitive hematopoietic stem cell |
| PS | primitive streak |
| primitive gut | A flat sheet of intraembryonic endoderm that will change into a tubular gut due to the folding of embryonic body-head, tail and lateral body folds. Synonym: archenteron, celenteron, endodermal canal, subgerminal cavity. (05 Mar 2000) |
|---|---|
| primitive knot | A local thickening of the blastoderm at the cephalic end of the primitive streak of the embryo. Synonym: Hensen's knot, Hensen's node, Hubrecht's protochordal knot, primitive knot, protochordal knot. (05 Mar 2000) |
| primitive meninx | The embryonic loose mesenchymatous tissue surrounding the brain and spinal cord; from it the three definite meninges (arachnoidea, dura mater, and pia mater) are derived. Synonym: meninx primitiva. Meninx serosa, obsolete term for arachnoidea; the arachnoid is actually not a serous membrane. (05 Mar 2000) |
| primitive node | A local thickening of the blastoderm at the cephalic end of the primitive streak of the embryo. Synonym: Hensen's knot, Hensen's node, Hubrecht's protochordal knot, primitive knot, protochordal knot. (05 Mar 2000) |
| primitive palate | In the early embryo, the mesoderm-filled shelf, formed from the medial nasal process, that anteriorly separates the oral cavity below from the primitive nasal cavities above. Synonym: primitive palate. (05 Mar 2000) |
| primitive perivisceral cavity | The space between the ectoderm and endoderm in the gastrula. Synonym: primitive perivisceral cavity. (05 Mar 2000) |
| primitive pit | The depression in the primitive node that serves to connect the notochordal canal with the surface ectoderm and the yolk sac. These connections are referred to as the neurenteric canal. (05 Mar 2000) |
| primitive reticular cell | A cell with processes making contact with those of other similar cell's to form a cellular network; along with the network of reticular fibres, the reticular cell's form the stroma of bone marrow and lymphatic tissues. (05 Mar 2000) |
| primitive ridge | One of the paired ridge's on either side of the primitive groove. (05 Mar 2000) |
| primitive streak | An ectodermal ridge in the midline at the caudal end of the embryonic disk from which arises the intraembryonic mesoderm; achieved by inward and then lateral migration of cells; in human embryos, it appears on day 15 and gives a cephalocaudal axis to the developing embryo. Synonym: germinal streak. (05 Mar 2000) |
| benign liver tumours | <radiology> EPITHELIAL TUMORS, nodular transformation, focal nodular hyperplasia, hepatocellular adenoma, MESENCHYMAL TUMORS, lipoma, myelolipoma, angiomyolipoma, leiomyoma, infantile haemangioendothelioma, haemangioma, benign mesothelioma, MIXED TISSUE TUMORS, mesenchymal hamartoma, benign teratoma, MISCELLANEOUS, adrenal rest tumours, pancreatic rest (12 Dec 1998) |
| brain tumours | Can be malignant or benign and can occur at any age. Primary brain tumours initially form in the brain tissue. Secondary brain tumours are cancers that have spread to the brain tissue (metastasized) from tissue elsewhere in the body. (12 Dec 1998) |
| pancreatic isleT-cell tumours | <radiology> Insulinoma (beta-cell), usually solitary, 85% benign, gastrinoma, small, slow-growing, multiple, 60% malignant, Zollinger-Ellison syndrome: mult. Intractable ulcers, VIPoma, vasoactive intestinal peptide (VIP), WDHA syndrome: watery diarrhoea, hypokalaemia, achlorhydria, Verner-Morrison syndrome, glucagonoma, hyperglycaemia, migratory necrolytic erythema APUDomas, associated with MEN-1 (12 Dec 1998) |
| malignant liver tumours | <radiology> EPITHELIAL TUMORS, hepatocellular, hepatoblastoma (7%), hepatocellular carcinoma (HCC) (75%), cholangiocellular (6%), cholangiocarcinomarcinoma, cystadenocarcinoma, MESENCHYMAL TUMORS, tumours of blood vessels, angiosarcoma, haemangioendothelioma, other tumours, embryonal sarcoma, fibrosarcoma, TUMORS OF MUSCLE TISSUE, leiomyosarcoma, rhabdomyosarcoma, MISCELLANEOUS, carcinosarcoma, teratoma, yolk sac tumour, carcinoid, squamous carcinoma, primary lymphoma see: benign liver tumours (12 Dec 1998) |
| venereal tumours, veterinary | Tumours most commonly seen on or near the genitalia. They are venereal, most likely transmitted through transplantation of cells by contact. Metastases have been reported. Spontaneous regression may occur. (12 Dec 1998) |