Using the formula on the right,
Cells/µL = 370 x 100 / 18 x 0.1
Cells/µL = 37000 / 1.8
Cells/µL = 20556 or 2.06 x 104
A sample of cerebrospinal fluid is diluted 1:100; the standard 9 squares of a hemocytometer are counted on each side for a total of 18 large squares.
Side 1-- 186 nucleated cells counted
Side 2-- 184 nucleated cells counted
total nucleated cells = 370
Using the standard hemocytometer formula shown on the right, what is the nucleated cell count per microliter (µL)?
An automated method for measuring chloride which generates silver ions in the reaction is called:
The clue to the identification of the colony seen in the upper frame is the gram stain in the lower frame, in which are seen short, rounded, gram positive bacilli, many of which possess distinct spores. As the colonies grew aerobically, the presence of spores indicates Bacillus species. The colonies are spreading, smooth, yellow-white and non-hemolytic. The lack of hemolysis and the small size of the bacterial cells suggests a species other than Bacillus cereus, the species causing most human infections. The isolate was identified as Bacillus circulans, which is consistent with the gram stain morphology. Clostridium septicum also produces spores; however, this species is an anaerobe and would grow poorly if at all and not produce spores aerobically. Listeria monocytogenes and Lactobacillus species are gram positive bacilli; however, neither of these produce spores.
The colonies seen in the upper frame, grown after 48 hours incubation aerobically at 35°C, and the accompanying gram stain in the lower frame are uncommonly associated with human disease, but have been associated with septicemia, bronchopneumonia, osteomyelitis and other infections, particularly in intravenous drug users. The most likely identification is:
Howell-Jolly bodies are composed of DNA, usually left from the nucleus, that appears as a round, dark-staining inclusion in the cytoplasm of red blood cells. Howell-Jolly bodies can be found in various conditions including splenectomy and anemia.
Remnants of erythrocyte nuclei, nuclear fragments, or aggregates of chromosomes are called:
In this case, the pH may become more alkaline, perhaps above 8.0, if the bacteria in the sample are proliferating during the extended room-temperature wait time.
A urine specimen was collected at 6:00 a.m. and remained at room temperature until it was received in the laboratory at 3:30 p.m. How may the pH of the specimen be affected by the extended time at room temperature if bacteria are present in the specimen?
