| IOU | intensive care observation unit; international opacity unit |
|---|---|
| IRU | industrial rehabilitation unit; interferon reference unit |
| IU | immunizing unit; international unit; intrauterine; in utero; 5-iodouracil |
| KU | kallikrein unit; Karmen unit |
| LU | left upper [limb]; loudness unit; Lupron; lytic unit |
| ventral primary rami of lumbar spinal nerves | See: ventral primary ramus of spinal nerve. Synonym: rami ventrales nervorum lumbalium. (05 Mar 2000) |
|---|---|
| ventral primary rami of sacral spinal nerves | See: ventral primary ramus of spinal nerve. Synonym: rami ventrales nervorum sacralium. (05 Mar 2000) |
| ventral primary ramus of spinal nerve | <anatomy, nerve> The larger, anterolaterally-directed major terminal branch (with the dorsal primary ramus) of all 31 pairs of mixed spinal nerves, formed at the intervertebral foramen. Most ventral primary rami, especially those involved in the innervation of the limbs, participate in the formation of the major nerve plexuses (cervical, brachial, and lumbosacral) and lose their identities. Most in the thoracic region, however, remain separate from adjacent rami to become the intercostal and subcostal nerves. Ventral primary rami provide innervation to the anterolateral body wall and trunk. Nomina Anatomica lists ventral primary rami as "rami ventrales" for each group of spinal nerves: 1) cervical (nervorum cervicalium ), 2) thoracic (nervorum thoracicorum ), 3) lumbar (nervorum lumbalium ), 4) sacral (nervorum sacralium )m, and 5) coccygeal (nervi coccygei ). Synonym: ramus ventralis nervi spinalis, anterior primary division. (05 Mar 2000) |
| Ghon's primary lesion | Calcification seen in pulmonary parenchyma (usually mid-lung area) and hilar nodes resulting from earlier, usually childhood, infection with tuberculosis. Synonym: Ghon's complex, Ghon's focus, Ghon's primary lesion. (05 Mar 2000) |
| persistent anterior hyperplastic primary vitreous | A unilateral congenital abnormality occurring in full-term infants; characterised by a retrolental fibrovascular membrane formed by persistent primary vitreous with remnants of the hyaloid artery and tunica vasculosa lentis; associated with leukokoria, microphthalmos, shallow anterior chamber, and elongated ciliary processes. (05 Mar 2000) |
| persistent posterior hyperplastic primary vitreous | A unilateral congenital anomaly in full-term infants; associated with a congenital retinal fold and a vitreous membranous stalk containing remnants of the hyaloid artery. (05 Mar 2000) |
| posterior primary division | <anatomy, nerve> The smaller, posteriorly-directed major terminal branch (with the ventral primary ramus) of all 31 pairs of mixed spinal nerves, formed at the intervertebral foramen and turning abruptly posteriorly to divide into lateral and medial branches, both of which will supply the deep (true) muscles of the back. The medial branch (rami medialis ) of the dorsal primary ramus also supplies articular branches to the zygopophyseal joints and the periosteum of the vertebral arch. In the neck and upper back, the medial branch continues through the deep and superficial back muscles to supply overlying skin; in the lower back, the lateral branch does this. Nomina Anatomica lists dorsal primary rami as "rami dorsales" for each group of spinal nerves: 1) cervical (nervorum cervicalium ), 2) thoracic (nervorum thoracicorum ), 3) lumbar (nervorum lumbalium ), 4) sacral (nervorum sacralium ), and 5) coccygeal (nervi coccygei ). Synonym: ramus dorsalis nervorum spinalium, ramus dorsalis, rami posteriores nervorum spinalium, dorsal branch, posterior primary division. (05 Mar 2000) |
| primary | Principal, primus, the first, first in order or in time of development, principal. Origin: L. Primarius (18 Nov 1997) |
| primary adhesion | Healing by fibrous adhesion, without suppuration or granulation tissue formation. Synonym: primary adhesion, primary union. (05 Mar 2000) |
| primary adrenocortical insufficiency | Adrenocortical insufficiency caused by disease, destruction, or surgical removal of the adrenal cortices. (05 Mar 2000) |
| primary aerodontalgia | Dental pain associated with expansion of trapped gases within a tooth, as under a filling or in an infected pulp. (05 Mar 2000) |
| primary alcohol | An alcohol characterised by the univalent radical, -CH2OH. (05 Mar 2000) |
| primary aldosteronism | An adrenocortical disorder caused by excessive secretion of aldosterone and characterised by headaches, nocturia, polyuria, fatigue, hypertension, potassium depletion, hypokalaemic alkalosis, hypervolaemia, and decreased plasma renin activity; may be associated with small benign adrenocortical adenomas. Synonym: Conn's syndrome, idiopathic aldosteronism. (05 Mar 2000) |
| primary amenorrhoea | Amenorrhoea in which the menses have never occurred. (05 Mar 2000) |
| primary amoebic meningoencephalitis | An invasive, rapidly fatal cerebral infection by soil amoebae, chiefly Naegleria fowleri, found in man and other primates and experimentally in rodents; the disease is characterised by a high fever, neck rigidity, and symptoms associated with upper respiratory infection such as cough and nausea; although organisms have been cultured from various organs, the brain is the primary focus, especially the olfactory lobes and cerebral cortex, which are first attacked by the amoebae that enter from nasal mucosa through the cribriform plate; death usually occurs two to three days after onset of symptoms. (05 Mar 2000) |