The error of determination of toxicity / by J.W. Trevan.

  • Trevan, J. W. (John William)
Date:
1927?]
Catalogue details

Licence: In copyright

Credit: The error of determination of toxicity / by J.W. Trevan. Source: Wellcome Collection.

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    sufficiently recognised. The fact that the “ minimal lethal dose/5 whether calculated for unit weight, or for surface area, or on any other basis, varies widely for different species has, perhaps, led to the looseness of its definition for any one species. For the accurate standardisation, by biological methods, of drugs which are not available in chemically pure form, it is essential to establish a more accurate definition of such terms as “ minimal lethal dose,” “ minimal effective dose,” etc. Fig. 1 gives the results of the injection of four poisons into animals. The abscissae are proportional to the doses injected, the scale obviously differing (O’Brien, Sndmersen and Range). The dose scale has been adjusted for each, so that the steepest parts of the curves are above one another. The numbers attached to the observed points represent the number of animals used to determine that point. Nx represents the “ ideal ” characteristic (see text). for the different drugs, and the ordinates give the percentage mortality for each dose injected. The number attached to each observed point represents the number of animals injected for its determination. The curves represent percentage mortalities produced by the subcutaneous injection of tincture of digitalis into frogs, by the intravenous injection of cocaine hydrochloride into