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Allens test

Allens test
For phenol: upon the addition of 5 or 6 drops of hydrochloric acid and then 1 of nitric acid to the suspected fluid, a red colour develops.
For strychnine: fluid is extracted with ether, which is then evaporated by means of drop-by-drop pipetting into a warmed porcelain dish or crucible; the residue is treated with a small bit of manganese dioxide and dilute sulfuric acid; a red-blue or violet colour develops if strychnine is present.
Origin: a.H. Allen
a test for radial or ulnar patency; either the radial or ulnar artery is digitally compressed by the examiner after blood has been forced out of the hand by clenching it into a fist; failure of the blood to diffuse into the hand when opened indicates that the artery not compressed is occluded.
Origin: Edgar van Nuys Allen


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