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Updated: Aug 17, 2026

Real-Time, Semi-Automated Fluorescent Measurement of the Airway Surface Liquid pH of Primary Human Airway Epithelial Cells
Published on: June 13, 2019
[24-hour esophageal pH monitoring. An analysis of 21 cases]
1Department of Internal Medicine, Second Teaching Hospital, Xi'an Medical University.
Abstract:
Esophageal pH monitoring was carried out with self-made portable pH recorder in 21 subjects for 24 hours under normal conditions. The results were as follows: the number of physiological gastroesophageal reflux (GER, pH < 4) was less than 23 times; the percentage of GER duration calculated by dividing the cumulative time of pH less than 4 by the total monitoring time was less than 1.4; the percentage was about 2 in upright position and less than 0.2 in lying position; the duration of the longest reflux episode was less than 5 minutes; the physiological gastroesophageal reflux occurred more often in upright position; while the pathological GER took place both in upright and lying position. Our study also indicated that the degree of esophagitis had no relation with the type of GER.
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