Mean gray-scale values were used to calculate the absorptive index, and standard deviation values were used to calculate heterogeneity. Values were recorded at 4 different locations within the same section that exhibited the positive reaction (corpus luteum or granulosa layer of follicles). Values were also taken from another 4 locations from the same section that exhibited no specific reaction (ovarian stroma for corpus luteum, theca interna for follicles). Areas for measurement were selected based on the uniform random sampling technique. antibiotic levaquin
The mean gray-scale value through a clear glass slide (with coverslip) was considered 100% transmittance, and the mean gray-scale value obtained by blocking the light path of the microscope was considered 0% transmittance. Mean gray-scale values obtained for follicles and corpora lutea were then converted to percentage transmittance. The values for percentage transmittance were averaged for the 4 samples and transformed to absorbance (negative value of log of percentage transmittance), and absorptive index was calculated by obtaining the ratio of absorbance of reactive to nonreactive areas. This method of reporting the results provides considerable advantage over other methods because the absorptive index value is independent of section thickness. The specific absorptive index for each of the follicles and corpora lutea was calculated by subtracting the absorptive index of the section treated with fol-listatin-adsorbed primary antiserum (nonspecific and unknown cross-reactions of the antiserum) from the absorptive index of sections treated with nonadsorbed primary antiserum.