Mallory’s Triple Stain: From 1 Different Sources
a histological stain consisting of water-soluble aniline blue or methyl blue, orange G, and oxalic acid. Before the stain is applied the tissue is mordanted, then treated with acid fuchsin and phosphomolybdic acid. Nuclei stain red, muscle red to orange, nervous tissue lilac, collagen dark blue, and mucus and connective tissue become blue. [F. B. Mallory]
Stain developed in 1884 by Hans Christian Gram, whereby Gram positive bacteria stain purple while Gram negative bacteria stain red.... gram stain
See NAEVUS.... port wine stain
Also known as DPT vaccine, this is an injection that provides IMMUNITY against DIPHTHERIA, pertussis (whooping-cough) and TETANUS. It is given as a course of three injections at around the ages of two, three and four months. A booster dose of diphtheria and tetanus is given at primary-school age. Certain infants – those with a family history of EPILEPSY, or who have neurological disorders or who have reacted severely to the ?rst dose – should not have the pertussis element of DPT. (See MMR VACCINE; IMMUNISATION.)... triple vaccine
The effect of the two ends of a bacillus staining while the centre of the rod remains unstained (eg in Yersinia pestis, the cause of Bubonic Plague) when stained with Giemsa stain.... bipolar staining
Bacteria can be stained with an iodine-based chemical dye called Gram’s stain (after the scientist who discovered the technique). Different bacteria react di?erently to exposure to the stain. Broadly, the bacterial specimens are stained ?rst with gentian violet, then with Gram’s stain, and ?nally counterstained with a red dye after a decolorising process. Bacteria that retain the gentian stain are called gram-positive; those that lose it but absorb the red stain are called gram-negative. Some species of staphylococcus, streptococcus and clostridium are gram-positive, whereas salmonella and Vibrio cholerae are gram-negative.... gram’s stain
See “blinding”.... triple-blind trial
One of the Romanowski stains used to stain blood films and blood parasites such as those causing relapsing fever, malaria trypanosomiasis and filariasis.... wright’s stain
The process of dyeing specimens of cells, tissues, or microorganisms in order for them to be clearly visible or easily identifiable under a microscope.... staining
a mixture of *methylene blue and *eosin, used for distinguishing different types of white blood cell and for detecting parasitic microorganisms in blood smears. It is one of the *Romanowsky stains. [G. Giemsa (1867–1948), German chemist]... giemsa’s stain
large irregular masses abnormally located in the hepatocytes of the liver. They are found in patients with alcoholic hepatitis, alcoholic cirrhosis, Wilson’s disease, primary biliary cirrhosis, clinical obesity, and hepatoma. [F. B. Mallory (1862–1941), US pathologist]... mallory bodies
trauma of the mucosal lining at the junction of the oesophagus (gullet) and stomach following protracted vomiting and retching. It is associated with *haematemesis and rarely perforation of the oesophagus. [G. K. Mallory (1926– ), US pathologist; S. Weiss (1899–1942), US physician]... mallory–weiss syndrome
a group of stains used for microscopical examination of blood cells, consisting of variable mixtures of thiazine dyes, such as azure B, with eosin. Romanowsky stains give characteristic staining patterns, on the basis of which blood cells are classified. The group includes the stains of Leishmann, Wright, May-Grünwald, Giemsa, etc. [D. L. Romanowsky (1861–1921), Russian physician]... romanowsky stains
a group of azo compounds used for staining fats. The group includes Sudan I, Sudan II, Sudan III, Sudan IV, and Sudan black.... sudan stains
the application of a *stain to living tissue, particularly blood cells, removed from the body.... supravital staining
see gallop rhythm.... triple rhythm
1. (in *prenatal screening) a blood test that can be performed between the 15th and 20th weeks of pregnancy but has largely been replaced by combined first-trimester *PAPP-A screening and *nuchal translucency scanning. Levels of *alpha-fetoprotein (AFP), *unconjugated oestriol (uE3), and *human chorionic gonadotrophin (hCG) in the serum are computed with maternal age to determine the statistical likelihood of the fetus being affected by Down’s syndrome or spina bifida. The double test is similar but omits measurement of uE3. 2. see insulin stress test.... triple test
(intravital staining) the process of staining a living tissue by injecting a stain into the organism. Compare supravital staining.... vital staining
1. n. a dye used to colour tissues and other specimens for microscopical examination. In an acid stain the colour is carried by an acid radical and the stain is taken up by parts of the specimen having a basic (alkaline) reaction. In a basic stain the colour, carried by a basic radical, is attracted to parts of the specimen having an acidic reaction. Neutral stains have neither acidic nor basic affinities. A contrast stain is used to give colour to parts of a tissue not affected by a previously applied stain. A differential stain allows different elements in a specimen to be distinguished by staining them in different colours. 2. vb. to treat a specimen for microscopical study with a stain.... stain
an acid-fast *carbol fuchsin stain used specifically for identifying the tubercle bacillus. [F. Ziehl (1857–1926), German bacteriologist; F. K. A. Neelsen (1854–94), German pathologist]... ziehl–neelsen stain
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