Public health guidelines recommend that manipulation of samples for influenza testing be done inside a safety cabinet. Safety goggles could be worn if the specimen or procedure may be prone to splashes or sprays of infectious material. Utility gloves are not necessary.
Public health guidelines recommend that laboratory specimens for influenza testing must be manipulated using which of the following safety precautions?
This Gram stain is under-decolorized
This microscopic field is representative of other fields that were observed on a Gram-stained smear. Which of the following describes the quality of the smear?
The morphologic characteristic(s) associated with the Chediak-Higashi syndrome is (are):
Serum calcitonin is normally produced by the C cells of the thyroid. It functions to reduce serum calcium by inhibiting release of calcium from bone. It is a peptide with a molecular weight of 3400, and has a half life of approximately 12 minutes. It is characteristically elevated in medullary carcinoma of the thyroid. Since medullary carcinoma often occurs as an autosomal disorder, family members of patients with this condition should be screened for serum calcitonin.
Serum calcitonin is typically elevated in which of the following conditions:
On the red cell membrane, there is a bicarbonate / chloride exchanger. This exchanger allows for bicarbonate to leave the red cells while chloride is allowed inside.
In blood, bicarbonate leaves the red blood cell and enters the plasma through an exchange mechanism with:
Antibodies in the Rh system typically exhibit which one of the following characteristics?
Any oxidase-positive organism can be excluded from the Enterobacteriaceae. The other characteristics are as a rule present in these organisms.
Which of the following is not true about members of the Enterobacteriaceae:
Haemophilus influenzae is both X and V factor dependent for growth, and is the most common cause of obstructive laryngitis and epiglottitis. H. parainfluenzae is only V-factor dependent and causes only mild pharyngitis, rarely obstructive in nature. H. aphrophilus can be part of the normal upper respiratory flora in humans, does not cause pharyngitis, and is not X or V-factor dependent for growth. Although H. haemolyticus is both X and V-factor dependent, it is beta hemolytic on blood agar and is generally considered non pathogenic.
Acute obstructive epiglottitis, both in adults and children, is caused by the bacterial species shown in this split screen photograph. The colonies recovered on chocolate agar (upper frame) required both hematin and NAD, (as shown by colony growth only between the X and V strips in the lower frame). The most likely identification is: