Fig. 4From: Evaluation of a simple method for storage of blood samples that enables isolation of circulating tumor cells 96 h after sample collectionAnalysis of gene-expression levels in CD45-negative cells isolated from blood samples taken from a patient with cancer and stored for 0–96 h. Gene expression was determined by qPCR, and threshold cycle (Ct) values for specific genes were compared with Ct values for 18S rRNA as an endogenous reference gene, giving ΔCt valuesBack to article page