Standardization of Cobra (Naja Flava) Venom Using the Graded Response Method

[摘要] The relationship between dosage of Naja flava venom and death-time of mice has been examined from experiments using intravenous injection. The observations were found to be well represented by the equation .![Figure][1]From this formula, a function of death-time can be constructed that has a linear regression on the logarithm of the dose over a wide range of doses, the function being . The logarithm of the time also is linearly related to the log dose over very nearly the same dose range. For both these response metameters, and over the same range of doses, the variance was found to be almost independent of the mean.![Figure][1]Hence the potency of a preparation of venom may be assayed against a standard, using either f(T) or log T as a response metameter, in a parallel line assay of familiar type. The function f(T) has the advantage of giving a linear regression over a slightly greater range of doses, but redetermination of the numerical values of its parameters should precede its use in any other laboratory. At the South African Institute for Medical Research, assays of the (2 + 2) dose design have been found satisfactory; five trial assays reported in this paper used five animals at each of the four doses and gave limits of error of ±20% or less for a probability of 0.95. [1]: pending:yes

[学科分类] 生物科学（综合）