Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
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A lock (
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connected to the .gov website. Share sensitive
information only on official, secure websites.
Example of an echo-power versus time curve extracted from a region of interest in a tumor. The mean echo power measured for each image frame is represented by the black points. The curve fit to these data according to the log-normal model is represented by the solid black line. The shaded region represents the area under the curve for t = 0 to 25 seconds.
