The implications of recent ultraviolet observations of stellar transition-region lines for calculations of the Ca II and Mg II resonance lines are investigated. It is found that the adoption of high transition-region pressures for stars with active chromospheres, such as Lambda And and Alpha Aur, can be consistent with observed Ca II fluxes, contrary to the results obtained by Kelch et al. (1978) for Alpha Aur. Furthermore, the adoption of the high-pressure models removes a long-standing difficulty in the line profile calculations, since the deep central absorption present in earlier calculations is less pronounced or absent, in closer agreement with observations. The apparent contradiction between these models and the recent density diagnostic of Doschek et al. (1978) is also discussed.