| RDHBF | regional distribution of hepatic blood flow |
|---|---|
| RDW | red blood cell distribution width index |
| SDF | slow death factor; stress distribution factor |
| SFD | silo filler's disease; skin-film distance; small for dates; spectral frequency distribution |
| VD | vapor density; vascular disease; vasodilation, vasodilator; venereal disease; venous dilatation; ven... |
| double-masked experiment | A double-blind study conducted so neither the subject nor the observer know the identity of the control or variable. (05 Mar 2000) |
|---|---|
| double membrane | <cell biology> Two biomembrane layers, with an intermembranal space, surrounding certain organelles (e.g., mitochondria) or structures. (05 Mar 2000) |
| double minute | <molecular biology> Small pieces of a chromosome containing many copies of the same gene. (09 Oct 1997) |
| double minute chromosomes | <genetics, molecular biology> Paired, extrachromosomal elements lacking centromeres, often associated with a drug resistance gene. (05 Mar 2000) |
| double-mouthed uterus | Septate uterus in which the cervix is divided into two by a septum. Synonym: double-mouthed uterus, uterus biforis. (05 Mar 2000) |
| double outlet right ventricle | <cardiology, embryology> Incomplete transposition of the great vessels in which both the aorta and the pulmonary artery arise from the right ventricle, often associated with a subaortic ventricular septal defect. (12 Dec 1998) |
| double pedicle flap | A flap with two pedicles, one at each end. Synonym: double pedicle flap. (05 Mar 2000) |
| double pleurisy | Inflammation of the pleura on both sides of the thorax. Synonym: double pleurisy. (05 Mar 2000) |
| double pneumonia | <chest medicine> Lobar pneumonia involving both lungs. (05 Mar 2000) |
| double-point threshold | The least degree of separation of two points applied to the body surface that permits of their being felt as two. (05 Mar 2000) |
| double product | The product of systolic blood pressure multiplied by the heart frequency; a measure of heart work load. See: Robinson index. (05 Mar 2000) |
| double protrusion | The excessive forward projection of both the maxilla and the mandible in relation to the cranial base. Synonym: double protrusion. (05 Mar 2000) |
| double quotidian fever | Malaria in which two paroxysms of fever occur daily. (05 Mar 2000) |
| double-reciprocal plot | <statistics> A graph made to analyse how fast an enzyme can convert its substrate into its product, depending on how much substrate is present (its concentration) and to determine its maximum speed (after which the enzyme does not get any faster no matter how high the concentration of substrate gets), called Vmax. It is a plot of 1/v versus 1/[S], where v=rate of product formation and [S]=the concentration of the substrate. Synonym: Lineweaver-Burk plot, Woolf-Lineweaver-Burk plot. (05 Mar 2000) |
| double refraction | <microscopy> The refraction of light in two slightly different directions to form two rays or vector components. Each ray is polarized, and their vibration directions are perpendicular to each other. Furthermore, each ray has a different velocity, and therefore a different refractive index. See: birefringence. (05 Aug 1998) |