| EUS | endoscopic ultrasound; external urethral sphincter |
|---|---|
| EVD | external ventricular drainage; extravascular [lung] density |
| EXREM | external radiation-emission man [dose] |
| EXS | external support |
| ext | extension; extensive; extensor; exterior; external; extract; extreme, extremity |
| external surface of frontal bone | The convex outer surface of the frontal bone. Synonym: facies externa ossis frontalis. (05 Mar 2000) |
|---|---|
| external surface of parietal bone | The convex outer surface of the parietal bone. Synonym: facies externa ossis parietalis. (05 Mar 2000) |
| external traction | A pulling force created by using fixed anchorage (e.g., a headcap or bed frame) outside the oral cavity; principally used in the management of midfacial fractures. (05 Mar 2000) |
| external urethral orifice | The slitlike opening of the urethra in the glans penis, the external orifice of the urethra (in the female) in the vestibule, usually upon a slight elevation, the papilla urethrae. Synonym: ostium urethrae externum, external opening of urethra, meatus urinarius, orificium urethrae externum. (05 Mar 2000) |
| external urethral sphincter | Origin, ramus of pubis; insertion, with fellow in median raphe behind and in front of urethra; action, constricts membranous urethra; nerve supply, pudendal. Synonym: musculus sphincter urethrae, external urethral sphincter, Guthrie's muscle, musculus compressor urethrae, musculus constrictor urethrae, musculus sphincter urethrae membranaceae, sphincter muscle of urethra, Wilson's muscle. (05 Mar 2000) |
| external wall of cochlear duct | The wall that faces the outer side of the cochlea. Synonym: paries externus ductus cochlearis. (05 Mar 2000) |
| androgenic zone | A transient adrenocortical zone present in some rodents at birth, most notably in mice, situated between the zona reticularis and the adrenal medulla; it degenerates in males with the secretion at puberty and in females during their first pregnancy; it slowly enlarges in unmated females after puberty and does not degenerate until middle age; the X zone appears to secrete no hormone. Synonym: androgenic zone. Misnomer for the foetal adrenal cortex of primates. Synonym: foetal reticularis. (05 Mar 2000) |
| arcuate zone | The inner third of the basilar membrane of the cochlear duct extending from the tympanic lip of the osseous spiral lamina to the outer pillar cell of the spiral organ (of Corti). Synonym: zona arcuata, zona tecta. (05 Mar 2000) |
| Barnes' zone | The lower fourth of the pregnant uterus, attachment of the placenta to any part of which may cause dangerous haemorrhage. Synonym: cervical zone. (05 Mar 2000) |
| buffer zone | <ecology> An area of land separating two distinct land uses that acts to soften or mitigate the effects of one land use on the other. (09 Oct 1997) |
| capillary zone electrophoresis | A method for separating molecules extremely rapidly based on their electrophoretic mobility. (05 Mar 2000) |
| vascular zone | An area in the external acoustic meatus where a number of minute blood vessels enter from the mastoid bone. Synonym: spongy spot, zona vasculosa. (05 Mar 2000) |
| mantle zone | A layer of small B lymphocytes surrounding the paler-staining germinal centres of lymphoid follicles. (05 Mar 2000) |
| Marchant's zone | The area on the sphenoid and occipital bones at the base of the skull from which the dura mater is readily detached. (05 Mar 2000) |
| marginal zone | The outer, nonnuclear layer of the embryonic neural tube; into its fibrous network grow the longitudinal nerve fibres which eventually become the white matter of the cord and brain stem. Synonym: marginal zone. (05 Mar 2000) |