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smearTuberculosis A specimen gobbed on a glass slide, stained, washed in an acid solution, and examined by LM to detect AFB in a specimen. See Acid-fast bacilli, Wet mount.
smear(smer) [Old English. smerian, to anoint]
Procedure: The slide must be grease-free. It is cleaned with alcohol, rinsed in warm water, and wiped clean with a lint-free towel or lens paper.A small drop of blood is placed on the slide; the end of another slide (spreader slide) is placed against the first slide at a 45° angle and pulled back against the drop of blood so that the drop spreads between the point of contact of the two slides. Then the spreader slide is pushed forward against the first slide; the blood will form an even, thin smear. The slide is dried by waving it in the air; it should not be heated. The blood smear is covered with Wright's stain and allowed to stand 2 min. An equal amount of distilled water or buffer solution is added and mixed uniformly. It is allowed to stand 5 min. The stain is gently washed off and the slide is allowed to dry.