| OAR | organ at risk |
|---|---|
| OBF | organ blood flow |
| OC | obstetrical conjugate; occlusocervical; office call; on call; only child; optic chiasma; oral contra... |
| OPO | Organ Procurement Organization |
| OS | left eye [Lat. oculus sinister]; occipitosacral; occupational safety; office surgery; Omenn syndrome... |
| end-tidal | at the end of a normal expiration. (05 Mar 2000) |
|---|---|
| end-tidal sample | A sample of the last gas expired in a normal expiration, ideally consisting only of alveolar gas. (05 Mar 2000) |
| Jacobson's organ | A specialised part of the olfactory system located anteriorly in the nasal cavity within the nasal septum. Chemosensitive cells of the vomeronasal organ project via the vomeronasal nerve to the accessory olfactory bulb. The primary function of this organ appears to be in sensing pheromones which regulate reproductive and other social behaviours. While the structure has been thought absent in higher primate adults, data now suggests it may be present in adult humans. (12 Dec 1998) |
| zero end-expiratory pressure | Airway pressure which, at the end of expiration, equals atmospheric pressure. (05 Mar 2000) |
| Krause's end bulbs | Nerve terminals in skin, mouth, conjunctiva, and other parts, consisting of a laminated capsule of connective tissue enclosing the terminal, branched, convoluted ending of an afferent nerve fibre; generally believed to be sensitive to cold. Synonym: corpuscula bulboidea, bulboid corpuscles. (05 Mar 2000) |
| floating organ | An organ with loose attachments, permitting its displacement. Synonym: floating organ, ptotic organ. (05 Mar 2000) |
| flower-spray organ of Ruffini | One of the two types of sensory nerve ending associated with the neuromuscular spindle (the other being the annulospiral ending); in this type, the fibre branches spread out upon the surface of the intrafusal fibres like a spray of flowers. Synonym: flower-spray organ of Ruffini. (05 Mar 2000) |
| flush end | <molecular biology> The ends of a blunt-end DNA molecule, where both strands in the double-stranded DNA molecule are even with each other rather than one strand being longer than the other. (09 Oct 1997) |
| foetal organ maturity | <embryology> Functional competence of specific foetal organs or body systems. In humans, it is usually assessed by analysis of amniotic fluid, as in the assessment of foetal lung maturity by analysis for components of pulmonary surfactant. (08 Mar 2000) |
| lateral line sense organ | A structure in fish consisting of a long groove or canal extending along each side of the trunk and tail and branching in the head region; the groove or tube is lined with neuroepithelial cells, some of which are in groups known as neuromasts; its function appears to be the detection of vibrations of low frequency. Synonym: neuromast organ. (05 Mar 2000) |