About half of those who have mononucleosis have enlargement of the spleen, usually 2 to 3 weeks after they are infected. The incubation periodâthe time it takes symptoms to appear after a person becomes infected with the virusâcan be 4 to 6 weeks.Symptoms of mononucleosis usually last for 1 to 4 weeks, but it might take as long as 2 months before you feel well enough to resume all of your normal activities.bout half of those who have mononucleosis have enlargement of the spleen, usually 2 to 3 weeks after they are infected. The incubation periodâthe time it takes symptoms to appear after a person becomes infected with the virusâcan be 4 to 6 weeks.
hair analysis. chemical analysis of a hair sample to find possible evidence of exposure to a toxic substance. Molecules of lead compounds and other chemicals are absorbed and stored in hair shafts. Hair analysis is also used to determine possible causes of malnutrition.
Bioelectrical impedance analysis. Bioelectrical impedance analysis (BIA) is a commonly used method for estimating body composition, and in particular body fat. Since the advent of the first commercially available devices in the mid-1980s the method has become popular owing to its ease of use, portability of the equipment.