| aortic sac | In mammalian embryos, the endothelially lined dilation just distal to the truncus arteriosus; it is the primordial vascular channel from which the aortic arches arise and is homologous to the ventral aorta of gill-bearing vertebrates. (05 Mar 2000) |
|---|---|
| rami laterales ramorum dorsalium nervorum cervicalium/thoracalium/lumbalium/sac | Lateral branch of dorsal primary rami of spinal nerves. See: lateral branches. (05 Mar 2000) |
| gestational sac | <radiology> Arises from blastocyst which implants into secretory endometrium surrounded by echogenic trophoblast sac size: 6th week = 17mm;, 8th week = 31 mm, fills chorionic cavity by 12th week visualization of gestational sac, relative to beta-hCG levels: transabdominal scan: greater than 1800 IU/l, transvaginal scan: less than 500 IU/l = 20%, 500-1000 IU/l = 80%, greater than 1000 IU/l = 100%, relative to menstrual age, transabdominal scan: earliest by 5.5 weeks (10-12mm), transvaginal scan: routinely seen by 5-5.5 weeks see: double decidual sac (12 Dec 1998) |
| gestation sac | The gestation sac is the fluid-filled sac in which the foetus develops, visible with an ultrasound exam. (09 Oct 1997) |
| vitelline sac | <embryology, ornithology> One of the set of extra embryonic membranes, growing out from the gut over the yolk surface, in birds formed from the splanchnopleure, an outer layer of splanchnic mesoderm and an inner layer of endoderm. (18 Nov 1997) |
| pericardial sac | <anatomy> A tough fibrous membrane that envelops and protects the heart. (27 Sep 1997) |
| greater cul-de-sac | The portion of the stomach that lies above the cardiac notch. Synonym: fundus gastricus, fundus ventriculi, greater cul-de-sac. (05 Mar 2000) |
| Gruber's cul-de-sac | A lateral diverticulum in the suprasternal space beside the medial extremity of the clavicle behind the sternal attachment of the sternocleidomastoid muscle. (05 Mar 2000) |
| chorionic sac | 1. Protective membrane around the eggs of insects and fishes. 2. Extraembryonic membrane surrounding the embryo of amniote vertebrates. The outer epithelial layer of the chorion is derived from the tropoblast. (18 Nov 1997) |
| conjunctival cul-de-sac | The space formed by the junction of the bulbar and palpebral portions of the conjunctiva, that of the upper lid being the fornix conjunctivae superior and that of the lower lid the fornix conjunctivae inferior. Synonym: fornix conjunctivae, conjunctival cul-de-sac, retrotarsal fold. (05 Mar 2000) |
| conjunctival sac | The space bound by the conjunctival membrane between the palpebral and bulbar conjunctiva; into which the lacrimal fluid is secreted; it opens anteriorly between the eyelids. Synonym: saccus conjunctivae. (05 Mar 2000) |
| cul-de-sac | 1. A blind pouch or tubular cavity closed at one end; e.g., diverticulum; caecum. Synonym: rectouterine pouch. Origin: Fr. Bottom of a sack (05 Mar 2000) |
| cul-de-sac smear | A cytologic specimen of material obtained by aspirating the pouch of Douglas from the posterior vaginal fornix and prepared by smearing, centrifuging, or filtering; used principally for ovarian cancer. (05 Mar 2000) |
| preputial sac | The space between the prepuce and the glans penis. (05 Mar 2000) |
| sac | A pouch or cavity. (09 Oct 1997) |