 Then the tip of the endoscope was advanced down into the second portion of the duodenum, one biopsy was taken there, and then, the tip of the endoscope was brought back to the first portion, and two biopsies were taken there. 
Then the tip of the endoscope was advanced down into the second portion of the duodenum , one biopsy was taken there , and then , the tip of the endoscope was brought back to the first portion , and two biopsies were taken there .