Search results
Results from the WOW.Com Content Network
In microscopy, negative staining is an established method, often used in diagnostic microscopy, for contrasting a thin specimen with an optically opaque fluid. In this technique, the background is stained, leaving the actual specimen untouched, and thus visible. This contrasts with positive staining, in which the actual specimen is stained.
Negative staining is able to stain the background instead of the organisms because the cell wall of microorganisms typically has a negative charge which repels the negatively charged stain. The dyes used in negative staining are acidic. [1] Note: negative staining is a mild technique that may not destroy the microorganisms, and is therefore ...
Gram stain (Gram staining or Gram's method), is a method of staining used to classify bacterial species into two large groups: gram-positive bacteria and gram-negative bacteria. It may also be used to diagnose a fungal infection. [1] The name comes from the Danish bacteriologist Hans Christian Gram, who developed the technique in 1884. [2]
Positive histologic stains that aid in the diagnosis of conditions of or affecting the human integumentary system Stain Cell, material, and/or structure(s) stained Condition(s) in which stain is positive Actin-specific enolase: Infantile digital fibromatosis: AE1/AE3: Squamous cell carcinoma: Alcian blue: Lipoid proteinosis Papular mucinosis ...
One commonly recognizable use of differential staining is the Gram stain. Gram staining uses two dyes: Crystal violet and Fuchsin or Safranin (the counterstain) to differentiate between Gram-positive bacteria (large Peptidoglycan layer on outer surface of cell) and Gram-negative bacteria. Acid-fast stains are also differential stains.
Eosin methylene blue (EMB, also known as "Levine's formulation") is a selective and differential media used for the identification of Gram-negative bacteria, [1] specifically the Enterobacteriaceae. EMB inhibits the growth of most Gram-positive bacteria. EMB is often used to confirm the presence of coliforms in a sample.
The H&E staining procedure is the principal stain in histology [3] [7] [2] [5] in part because it can be done quickly, [7] is not expensive, and stains tissues in such a way that a considerable amount of microscopic anatomy [9] [10] is revealed, [7] [5] [4] and can be used to diagnose a wide range of histopathologic conditions. [8]
An advantage of using this method, rather than regular positive stains like methylene blue or carbol fuchsin, is that prior fixation by heat or alcohol is not needed, so the organisms are seen in more lifelike shapes. Furthermore, negative staining with nigrosin can reveal some microorganisms that cannot be stained by regular methods.