Correlation between the granulocyte CD88 expression and the APACHE II score on day 1. Upward arrows indicate an increase from onset of the severe sepsis in APACHE II score >2, and downward arrows indicate a decrease from onset of the severe sepsis in APACHE II score >2. Double-directed arrows represent changes <2.○, a patient with a duration of sepsis of 12 hours; ??, a patient with a duration of 13–24 hours; and ??, a patient with a duration >24 hours. Patients who died within 28 days are marked with shaded symbols. A regression line has been calculated using the method of least squares.