| balanced polymorphism | <genetics> A type of polymorphism where the many morphs are alleles. The polymorphism is maintained in a population rather than the norm of one allele eventually becoming the only allele in the population, because individuals who are heterozygous, or have two different alleles, are more adaptive (more fit) than individuals who are homozygous, or have two copies of the same allele. (09 Oct 1997) |
|---|---|
| balanced stock | <genetics> A genetic strain of any of several lab organisms (like fruit flies) which can be maintained as heterozygous individuals without requiring constant artificial selection for the heterozygotes, due to a number of lethal recessive genes with the result that the homozygous females are sterile (unable to produce offspring) and the males with the wrong recessive alleles are dead. (Male fruit flies are not homozygous or heterozygous because they only have one allele per particular genetic loci in question). (09 Oct 1997) |
| balanced translocation | <genetics> A number of the chromosomal mutations called translocations, where a segment of DNA abnormally becomes attached to the wrong chromosome, which results in two nonhomologous chromosomes being able to cross over, something which normally can occur only between homologous chromosomes. (09 Oct 1997) |
| mechanically balanced occlusion | A balanced occlusion without reference to physiologic considerations, as on an articulator. (05 Mar 2000) |
| physiologically balanced occlusion | A balanced occlusion that is in harmony with the temporomandibular joints and the neuromuscular system. (05 Mar 2000) |
| dental occlusion, balanced | Dental occlusion in which the occlusal contact of the teeth on the working side of the jaw is accompanied by the harmonious contact of the teeth on the opposite (balancing) side. (12 Dec 1998) |
| Arneth formula | The normal, approximate ratio of polymorphonuclear neutrophils, based on the number of lobes in the nuclei, as follows: 1 lobe, 5%; 2 lobes, 35%; 3 lobes, 41%; 4 lobes, 17%; 5 lobes, 2%. (05 Mar 2000) |
| Bazett's formula | A formula for correcting the observed Q-T interval in the electrocardiogram for cardiac rate: corrected Q-T = Q-T sec/✓R -R sec. (05 Mar 2000) |
| Bernhardt's formula | <nutrition> A formula used to calculate the ideal weight, in kilograms, for an adult; it is the height in centimeters times the chest circumference in centimeters divided by 240. (14 Aug 2000) |
| Black's formula | A translation of Pignet's formula into British measurements: F = (W + C) -H; F is the empirical factor, W is the weight in pounds, C the chest girth in inches at full inspiration, and H the height in inches; a man is classed as very strong when F is over 120, strong between 110 and 120, good 100 to 110, fair 90 to 100, weak 80 to 90, very weak under 80. (05 Mar 2000) |
| Broca's formula | A fully developed man (30 years old) should weigh as many kilograms as he is centimeters in height over and above 1 meter. (05 Mar 2000) |
| Van Slyke's formula | The value obtained when the square root of the urine flow (when below 2 ml/min) is multiplied by the urine urea concentration and divided by the whole blood urea concentration; represents an old empirical adjustment for the effect of low urine flow on urea excretion; sometimes corrected for body size by dividing by some function of body weight or surface area. Later, plasma concentration was substituted for blood concentration in the calculation. The normal value is about 54 ml/min per 1.73 m2 in an adult person. Synonym: Van Slyke's formula. (05 Mar 2000) |
| Mall's formula | A formula for determining the age (in days) of a human embryo; calculated as the square root of its length (measured from vertex to breech) in millimeters multiplied by 100. (05 Mar 2000) |
| Ranke's formula | A = grams of albumin per liter of a serous fluid: then, A = (sp. Gr. -1000) × 0.52 -5.406. (05 Mar 2000) |
| rational formula | In chemistry, a formula that indicates the constitution as well as the composition of a substance. (05 Mar 2000) |