Figure 4.

(A) Oscillation of the mean blood pressure from 12/9/97 1118 to 12/10/97 1118 h (rat code: 12099701). (B) Oscillation of the mean blood pressure (smoothed by method explained in text). (C) The oscillation of the mean, systolic, and diastolic pressure in one hour (12/9/97 1118 to 1218 h). (D) The Gumbel extreme value statistics of the maximum systolic blood pressure in successive 10-min periods from 12/12/97 1050 to 2150 h plotted against a reduced variate that is related to cumulative probability on a Gumbel distribution paper. (E) The Gumbel extreme value statistics of a data set of the largest systolic pressure in successive 1-min periods. (F) The return period for any assumed extreme values of systolic pressure, based on the Gumbel statistical distribution of the extreme systolic pressure recording taken on 12/12/97 1050 to 2150 h.