Of 530 patients with no alloantibodies at base line , 13 percent of those in the control group produced lymphocytotoxic antibodies and their thrombocytopenia became refractory to platelet transfusions , as compared with 3 percent in the F-PC group , 5 percent in the UVB-PC group , and 4 percent in the F-AP group ( P < or = 0.03 for each treated group as compared with the controls ; there were no significant differences among the treated groups ) .
