However, inter-observer agreement using uptake ratios was slightly inferior compared to quantitation.
This highlights the pitfalls of using uptake metrics such as SUVmax, that are so sensitive to partial volume effects and reconstruction parameters, with fixed thresholds for malignancy.
When RI was calculated using uptake from 30 to 40 min post injection, similar results were obtained (r2 = 0.72 and r2 = 0.73 for RIP and RIWB, respectively).
This is most likely caused by the greater variability due to differing SUVmean values between readers, which was effectively magnified by the smaller magnitude of the reported quantities when using uptake ratios.
Although uptake data [ 4] were nominally available for all three doses, we felt constrained to use uptake to the second dose only as the principal dependent variable.
A similar pattern of blood flow response in the P22 tumour was obtained using uptake of I-IAP as for RBC flux (comparison of Figures 1 and 3).
The DAPA flux kinetics, with and without ammonium chloride, was well fitted by a reaction-diffusion model with reversible cellular uptake (modelled as binding), using uptake parameters determined in separate experiments with V79-171b single-cell suspensions.
When phagocytic capacity by irradiated DC was assessed using uptake of fluorescently labelled human SW480 tumour cells, there was again reduced (though still significant) uptake on irradiation by IDC, and no change for MDC.
Semiquantitative measurements of the tracer uptake using standardized uptake value (SUVmax) were obtained by measuring the ratio of the decay-corrected tracer uptake per gram of tumor to the injected dose, normalized for body weight.
