Abstract: Method and apparatus for analyzing the propagation of arterial pulse waves in a patient's circulatory system. The apparatus comprises R-wave detecting means for outputting an R-wave timing signal at the time of detection of the R-wave component contained in a detected electrocardiographic signal. A pulse wave peak detecting means is provided for outputting a peak timing signal at the time of the detection of a selected peak of the arterial pulse wave detected in the peripheral blood vessels of a patient's circulatory system. A pulse wave propagation time counter is provided for successively counting the time interval from the input of the R-wave timing signal to the input of the peak timing signal, and a pulse wave propagation time analyzer is provided for analyzing the distribution of pulse wave propagation times and other detected biophysiological parameters, from which an effective diagnosis of the condition of the patient's circulatory system can be made.

Abstract: A preserving solution for blood or packed blood cells comprising an anticoagulant solution containing citric acid, sodium citrate and glucose; an effective amount of glycerin; and an effective amount of mannitol. The use of the blood preserving solution makes it possible to preserve blood at a low temperature of from the freezing temperature of plasma (about -1.degree. C.) to 3.degree. C. and to extend the period of preservation to 4 or 5 weeks without any further special additives.