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Updated: Aug 17, 2026

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Window on a Microworld: Simple Microfluidic Systems for Studying Microbial Transport in Porous Media
Published on: May 3, 2010
Fluid transport: concentration of the intercellular compartment
Abstract:
Intercellular spaces of Periplaneta rectal pads are visible at a magnification of x 100 and distend during fluid uptake. Samples (0.025 to 0.1 nanoliter) obtained by micropuncture from the spaces were consistently more concentrated than the fluid in the rectal lumen. This observation supports the hypothesis of "local" osmosis in epithelial fluid transport.
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