Despite the lack of changes in Q ( H ) and the number or proliferative capacity of CD34 ( + ) / KDR ( + ) / CD117 ( + ) or CD34 ( + ) / KDR ( + ) / CD31 ( + ) cells , the NT regimen elevated both Q ( M ) and plasma nitrite/nitrate levels and suppressed the shedding of endothelial cells ( CD34 ( - ) / KDR ( + ) / phosphatidylserine ( + ) cells ) .