A method is described for inhibiting IgE production which comprises administering, in an amount effective to inhibit IgE production, a prostaglandin of the formula: ##STR1## or a pharmaceutically acceptable non-toxic salt thereof, in which R is hydrogen, C.sub.1 -C.sub.5 alkyl, C.sub.3 -C.sub.8 cycloalkyl, phenyl, or mono, di- or tri-substituted phenyl in which the substituents, are selected from the group consisting of bromo, chloro, fluoro, iodo, C.sub.1 -C.sub.5 alkyl, hydroxy, nitro, acetyl, alkoxy, carboxy, acetoxy, amino, mono- or di- alkyl amino, amido and acetamido; R.sub.1 and R.sub.2 independently are hydrogen or C.sub.1 -C.sub.5 alkyl, n.sub.3, n.sub.4, n.sub.5, n.sub.6, n.sub.7, and n.sub.8 independently are zero or one; when n's are zeros, R.sub.3 and R.sub.4 together, R.sub.4 and R.sub.5 together, R.sub.5 and R.sub.6 together, and R.sub.7 and R.sub.8 together are double bonds; when n's are ones, R.sub.3, R.sub.5, R.sub.6, R.sub.7 and R.sub.8 independently are hydrogen, R.sub.4 is hydrogen or methyl, or R.sub.3 and R.sub.4 together, R.sub.4 and R.sub.5 together, or R.sub.5 and R.sub.6 together are methylene.
A system that determines the integration time periods for the channels of a color scanner. The slowest channel or longest time period is used to set a line scan clock period or transfer clock period of the scanner. The exposure start times for the other channels, which are charged faster than the slowest channel, are set relative to the transfer clock. The transfer clock and exposure start time of all channels is adjusted if necessary for the density of the film being scanned.
