| closed system | <biology, ecology> A chemical or biological system that exchanges no matter or energy with the ouside environment. (12 Mar 1998) |
|---|---|
| covalently closed circular DNA | <molecular biology> A circular molecule of double-stranded DNA which is supercoiled, or coiled up on itself due to internal tensions, because there are no breaks in the phosphate backbone (upon which the nucleotide bases are mounted) to relieve the tensions and allow it to form an open circle. (09 Oct 1997) |
| head injuries, closed | Organic or functional damage resulting from trauma to the head where continuity of the scalp and mucous membranes is maintained. When brain injury results from closed head injuries, the primary cause is mechanical stretching and shearing of nerve fibres. Also common are focal intracranial lesions including haematomas and contusions. (12 Dec 1998) |
| semi-closed anaesthesia | Inhalation anaesthesia using a circuit in which a portion of the exhaled air is exhausted from the circuit and a portion is rebreathed following absorption of carbon dioxide. (05 Mar 2000) |
| semi-closed circle | A circuit for administration of an inhalation anaesthetic in which partial rebreathing with carbon dioxide absorption is combined with loss from the circuit of a portion of respired gases through valves. (05 Mar 2000) |
| ecological systems, closed | Systems that provide for the maintenance of life in an isolated living chamber through reutilization of the material available, in particular, by means of a cycle wherein exhaled carbon dioxide, urine, and other waste matter are converted chemically or by photosynthesis into oxygen, water, and food. (12 Dec 1998) |
| fractures, closed | Fractures in which the break in bone is not accompanied by an external wound. (12 Dec 1998) |
| Broca's pouch | A pear-shaped encapsulated collection of connective tissue and fat in each labium majus. Synonym: Broca's pouch. (05 Mar 2000) |
| paracystic pouch | A peritoneal depression formed by the reflection of the peritoneum from the lateral pelvic wall onto the roof of the bladder; in the female, it is the lateral portion of the uterovesical pouch, separated from the pararectal pouch by the broad ligament. Synonym: fossa paravesicalis, paracystic pouch, paravesical pouch. (05 Mar 2000) |
| Rathke's pouch | A tubular outgrowth of ectoderm from the stomodeum of the embryo; it grows dorsad toward the infundibular process of the diencephalon, around which it forms a cup-like mass, giving rise to the pars distalis and pars juxtaneuralis of the hypophysis. Synonym: craniopharyngeal canal, hypophyseal pouch, Rathke's diverticulum, Rathke's pocket, Rathke's pouch. (05 Mar 2000) |
| Rathke's pouch tumour | <oncology, tumour> A form of primary brain tumour which develops in the pituitary gland. These tumours often secrete increased quantities of pituitary hormones (for example growth hormone) which can result in conditions such as gigantism and acromegaly. They are often benign and rare and comprise less than 5% of childhood brain tumours. Other symptoms include vision changes, headache and weight gain. Treatment often includes a combination of surgery and radiation therapy. (27 Sep 1997) |
| pararectal pouch | A peritoneal depression on either side of the rectum formed by peritoneal (sacrogenital) folds passing from the posterolateral pelvic wall to the central pelvic viscera. The fossa is a lateral extension of the male rectovesical pouch or the female rectouterine pouch. Synonym: pararectal pouch. (05 Mar 2000) |
| paravesical pouch | A peritoneal depression formed by the reflection of the peritoneum from the lateral pelvic wall onto the roof of the bladder; in the female, it is the lateral portion of the uterovesical pouch, separated from the pararectal pouch by the broad ligament. Synonym: fossa paravesicalis, paracystic pouch, paravesical pouch. (05 Mar 2000) |
| rectouterine pouch | <anatomy> A pocket formed by the deflection of the peritoneum from the rectum to the uterus. Synonym: excavatio rectouterina, cavum douglasi, cul-de-sac, Douglas' cul-de-sac, Douglas' pouch, pouch of Douglas, rectovaginouterine pouch. (05 Mar 2000) |
| rectovaginouterine pouch | <anatomy> A pocket formed by the deflection of the peritoneum from the rectum to the uterus. Synonym: excavatio rectouterina, cavum douglasi, cul-de-sac, Douglas' cul-de-sac, Douglas' pouch, pouch of Douglas, rectovaginouterine pouch. (05 Mar 2000) |