| atresia folliculi | A normal process affecting the primordial ovarian follicles in which death of the ovum results in cystic degeneration followed by cicatricial closure. (05 Mar 2000) |
|---|---|
| atresia iridis | Congenital absence of the pupillary opening. Synonym: atretopsia. (05 Mar 2000) |
| atresic | <embryology> Having an abnormal closure or absence of a body opening or tubular organ (for example, a child born without an oesophagus would have an atretic birthdefect). (09 Oct 1997) |
| atresic teratosis | A teratosis in which any of the normal orifices, such as the nares, mouth, anus, or vagina, is imperforate. (05 Mar 2000) |
| atretic | <embryology> Having an abnormal closure or absence of a body opening or tubular organ (for example, a child born without an oesophagus would have an atretic birthdefect). (09 Oct 1997) |
| atretic corpus luteum | A retrogressed corpus luteum characterised by increasing cicatrization and shrinkage of the cicatricial core with an amorphous, convoluted, completely hyalinised lutein zone surrounding the central plug of scar tissue. Synonym: albicans, atretic corpus luteum, corpus candicans. Corpora allata, a pair of juvenile hormone-producing endocrine glands located near the brain in insects; action of the juvenile hormone is interrelated with that of brain hormone and ecdysone; a high concentration of the hormone at the time of molting will cause production of an additional larval instar; removal at an early larval stage causes precocious pupation, resulting in the formation of a midget adult; implantation at late larval stages can cause development of an oversized adult. (05 Mar 2000) |
| atretic ovarian follicle | A follicle that degenerates before coming to maturity; great numbers of such atretic follicle's occur in the ovary before puberty; in the sexually mature woman, several are formed each month. Synonym: corpus atreticum. (05 Mar 2000) |
| atreto- | Lack of an opening. Origin: G. Atretos, imperforate fr. A-, not + tretos, perforated, fr. Tetraino, titremi, to bore through, to pierce. (05 Mar 2000) |
| atretoblepharia | Synonym: symblepharon. Origin: atreto-+ G. Blepharon, eyelid (05 Mar 2000) |
| atretocystia | Congenital or acquired absence of an opening of a bladder. Origin: atreto-+ G. Kystis, bladder (05 Mar 2000) |
| atretogastria | Congenital absence of an opening of the stomach. Origin: atreto-+ G. Gaster, stomach (05 Mar 2000) |
| atretopsia | Synonym: atresia iridis. Origin: atreto-+ G. Ops, eye (05 Mar 2000) |
| atria | <anatomy, cardiology> The thin-walled chambers of the heart that pump blood into the ventricles. Consists of right atrium and left atrium. (27 Sep 1997) |
| atrial | <anatomy> Pertaining to an atrium. (16 Dec 1997) |
| atrial appendage | The small projection from each atrium hanging over like a small ear, more marked on the left, with a small cavity of its own. (05 Mar 2000) |