| tension | 1. The act of stretching. 2. The condition of being stretched or strained, the degree to which anything is stretched or strained. 3. <physics> Voltage. 4. <chemistry> The partial pressure of a gas in a fluid, for example, of oxygen in blood. Origin: L. Tensio, Gr. Tonos (13 Jan 1998) |
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| tension, arterial | The pressure of the blood within an artery, the arterial pressure. Also called the intra-arterial pressure. (12 Dec 1998) |
| tension curve | The direction of the trabeculae in cancellous bone tissue adapted to resist stress. (05 Mar 2000) |
| tension headache | <neurology> A benign form of headache that results from the painful spasm (muscle tightness) and inflammation of muscles of the head and neck. Tension headache is one of the most common forms of headache. Spasm and contraction of the head and neck muscles may occur in response to fatigue, overuse, eye strain, excessive smoking, stress, anxiety or depression. Sleeping in an abnormal position or prolonged work involving immobilisation of the neck in one position (typing, computers, etc.) are considered common triggers. Exercising and stretching the muscles of the head and neck can reduce the occurrence of muscle tension headaches. (13 Jan 1998) |
| tension, intraocular | The pressure within the eye. (12 Dec 1998) |
| tension, intravenous | The pressure of the blood within a vein, the venous pressure. (12 Dec 1998) |
| tension pneumothorax | A variety of spontaneous pneumothorax in which air enters the pleural cavity and is trapped during expiration; intrathoracic pressure builds to values higher than atmospheric pressure, compresses the lung, and may displace the mediastinum and its structures toward the opposite side, with consequent disadvantageous effects on blood flow. Synonym: pressure pneumothorax, valvular pneumothorax. (05 Mar 2000) |
| tension suture | <surgery> A heavy reinforcing suture placed deep within the muscles and fasciae of the abdominal wall to relieve tension on the primary suture line and thus obviate postoperative wound disruption. Synonym: tension suture. (05 Mar 2000) |
| tissue tension | A theoretical condition of equilibrium or balance between the tissues and cells whereby overaction of any part is restrained by the pull of the mass. (05 Mar 2000) |
| low tension glaucoma | Optic nerve atrophy and excavation with typical field defects of glaucoma but without abnormal increase in intraocular pressure. (05 Mar 2000) |
| relative molecular mass | The sum of the atomic weight's of all the atoms constituting a molecule; the mass of a molecule relative to the mass of a standard atom, now 12C (taken as 12.000). Relative molecular mass (Mr) is the mass relative to the dalton and has no units. See: atomic weight. Synonym: molecular mass, molecular weight ratio, relative molecular mass. (05 Mar 2000) |
| gram-molecular weight | Molecular weight expressed in grams. Compare: mole. (05 Mar 2000) |
| cloning, molecular | The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells. (12 Dec 1998) |
| models, molecular | Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures. (12 Dec 1998) |
| molecular | <chemistry> Of, pertaining to or composed of molecules: a very small mass of matter. (18 Nov 1997) |