| tympanic membrane | <anatomy> The eardrum. (13 Nov 1997) |
|---|---|
| tympanic membrane perforation | An opening in the tympanic membrane usually caused by trauma. There are four general categories: compression injuries (the most common and usually the result of a blow to the ear); instrumentation injuries (the second most common, usually inadvertent, caused often by cotton swabs or bobby-pins); burn-slag injuries (frequently seen in industry, from hot metal from machines or welding); and blast injuries (usually seen during war or as a result of terrorist bombing). In the absence of infection, most traumatic tympanic membrane perforations heal spontaneously. Persistent perforation is usually a manifestation of tubotympanitis, an inflammation of the eustachian tube and tympanic cavity (middle ear). (12 Dec 1998) |
| exocelomic membrane | A layer of cells delaminated from the inner surface of the blastocystic cytotrophoblast and from the envelope of the primary yolk sac during the second week of embryonic life. Synonym: Heuser's membrane. (05 Mar 2000) |
| external intercostal membrane | The membrane that replaces the external intercostal muscle anteriorly between costal cartilages. Synonym: membrana intercostalis externa. (05 Mar 2000) |
| extracorporeal membrane oxygenation | Application of a life support system that circulates the blood through an oxygenating system, which may consist of a pump, a membrane oxygenator, and a heat exchanger. Examples of its use are to assist victims of smoke inhalation injury, respiratory failure, and cardiac failure. (12 Dec 1998) |
| extraembryonic membrane | A structure or tissue that develops from the fertilised ovum but does not form part of the embryo proper. Synonym: embryonic membrane, extraembryonic membrane. (05 Mar 2000) |
| false membrane | <dermatology> A thick, tough fibrinous exudate on the surface of a mucous membrane or the skin, as seen in diphtheria. Synonym: croupous membrane, neomembrane, plica, pseudomembrane. (05 Mar 2000) |
| yolk membrane | The membrane enveloping the yolk; specifically, the thickened cell membrane of large-yolked ova. Synonym: ovular membrane, vitelline membrane. Sometimes used to designate the zona pellucida of a mammalian ovum. Synonym: yolk membrane. (05 Mar 2000) |
| keratogenous membrane | The area of the corium on which the nail rests; it is extremely sensitive and presents numerous longitudinal ridges on its surface. According to some anatomists, the nail bed is the portion covered by the body of the nail, the nail matrix being only the part on which the root of the nail rests. Synonym: matrix unguis, keratogenous membrane, nail matrix, onychostroma. (05 Mar 2000) |
| umbo of tympanic membrane | The projection on the inner surface of the tympanic membrane at the end of the manubrium of the malleus; this corresponds to the most depressed point of the membrane, viewed laterally, that is commonly called the umbo. Synonym: umbo membranae tympani, umbo. (05 Mar 2000) |
| undulating membrane | Undulatory membrane, a locomotory organelle of certain flagellate (trypanosome and trichomonad) parasites, consisting of a finlike extension of the limiting membrane with the flagellar sheath; wavelike rippling of the undulating membrane produces a characteristic movement. (05 Mar 2000) |
| Zinn's membrane | The anterior layer of the iris. (05 Mar 2000) |
| unit membrane | <cell biology> The three ply, approximately 7nm wide membrane structure found in all cells, composed of a fluid lipid bilayer with intercalated proteins. The unit membrane theory carries with it the presumption that all biological membranes have basically the same structure. (18 Nov 1997) |
| fenestrated membrane | An elastic membrane, as in elastic laminae of arteries. (05 Mar 2000) |
| fertilization membrane | A viscous membrane formed on the inner surface of the vitelline membrane from the cytoplasm of the egg cell after entry of the sperm, preventing the entry of additional sperm. (05 Mar 2000) |