Retrospective Study
Copyright ©The Author(s) 2015.
World J Gastroenterol. Jan 28, 2015; 21(4): 1197-1206
Published online Jan 28, 2015. doi: 10.3748/wjg.v21.i4.1197
Figure 1
Figure 1 Study area (Piauí State), located in the tropical zone in the northeastern region of Brazil.