| RVI | relative value index; right ventricle infarction |
|---|---|
| RVS | rectovaginal space; relative value scale/study; reported visual sensation; retrovaginal space |
| RVU | relative value unit |
| RF | radial fiber; radio frequency; receptive field; regurgitant fraction; Reitland-Franklin [unit]; rela... |
| RR | radiation reaction; radiation response; rate ratio; rational recovery [group]; recovery room; relati... |
| relative leukocytosis | An increased proportion of one or more types of leukocytes in the circulating blood, without an actual increase in the total number of white blood cells. (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) |
| relative polycythemia | A relative increase in the number of red blood cells as a result of loss of the fluid portion of the blood. (05 Mar 2000) |
| relative refractory period | The period between the effective refractory period and the end of the refractory period; fibres then respond only to high intensity stimuli and the impulses conduct more slowly than normally. (05 Mar 2000) |
| relative risk | <epidemiology> The proportion of diseased people amongst those exposed to the relevant risk factor divided by the proportion of diseased people amongst those not exposed to the risk factor. This should be used in those cohort studies where those with and without disease are followed to observe which individuals become diseased. (05 Dec 1998) |
| relative scotoma | A scotoma in which there is visual depression but not complete loss of light perception. (05 Mar 2000) |
| relative sensitivity | The sensitivity of a medical screening test as determined by comparison with the same type of test; e.g., sensitivity of a new serological test relative to sensitivity of an established serological test. (05 Mar 2000) |
| relative specificity | The specificity of a medical screening test as determined by comparison with the same type of test (e.g., specificity of a new serological test relative to specificity of an established serological test). (05 Mar 2000) |
| relative viscosity | The ratio of the viscosity of a solution or dispersion to the viscosity of the solvent or continuous phase. (05 Mar 2000) |
| 5-year relative survival rate | <statistics> The likelihood that a patient will not die from causes associated with his or her cancer for at least 5 years after diagnosis. This is the standard many professionals use when determining someone a survivor of cancer. (16 Dec 1997) |
| acetyl value | The milligrams of KOH required to neutralise the acetic acid produced by the hydrolysis of 1 g of acetylated fat; a measure of the hydroxy acids present in glycerides; notably high in castor oil. (05 Mar 2000) |
| beta, or beta-value | <radiobiology> Ratio of plasma kinetic pressure to magnetic-field pressure, proportional to the ratio of plasma kinetic energy density to magnetic field energy density. Beta is usually measured relative to the total, local field (loosely called beta toroidal), but sometimes the plasma pressure relative to only the poloidal component of the field (beta poloidal) or relative to some external field (like the maximum field at the magnetic coils) is more useful. There is also a normalised beta (beta_N) of interest when discussing the beta limit. (lots of help from Art Carlson with the above.) Because the cost of a reactor is strongly influenced by the strength of the magnetic field that must be provided, beta values are directly related to the economics of fusion power production. Beta is usually expressed as a percentage, with 5% generally believed to be the minimum value required for an economical fusion reactor. See: pressure, kinetic pressure, magnetic pressure, second stability. (09 Oct 1997) |
| biological value | <nutrition> The nutritional value of a protein, usually measured in comparison to the nutritional value of egg protein, which is the highest possible (BV=0.9 - 1.00). (21 Mar 1998) |
| buffer value | The power of a substance in solution to absorb acid or alkali without change in pH; this is highest at a pH value equal to the pKa value of the acid of the buffer pair. See: buffer capacity. Synonym: buffer index. (05 Mar 2000) |
| buffer value of the blood | The ability of the blood to compensate for additions of acid or alkali without disturbance of the pH. (05 Mar 2000) |