Fig. 2. Proliferative capacity expressed as (a) the percentage of proliferating lymphocytes and (b) the SI in displaced persons () and residents (•) after cultivation for 72 hours in the presence of PHA at the indicated concentrations. The percentage of proliferating lymphocytes ex vivo before cultivation (0 hours) is also presented (displaced persons, ; residents, ). Data are expressed as the median; vertical bars indicate the interquartile range (middle 50% of all data). The difference between groups for each PHA concentration or time point was assessed by use of the Mann-Whitney U test.