The pH in the upper gastrointestinal tract of young, healthy men and women was measured in the fasting state and after administration of a standard solid and liquid meal Calibrated Heidelberg capsules were used to record the pH continuously over the study period of approximately 6 hr In the fasted state, the median gastric pH was 17 and the median duodenal pH was 61 When the meal was administered the gastric pH climbed briefly to a median peak value of 67, then declined gradually back to the fasted state value over a period of less than 2 hr In contrast to the pH behavior in the stomach, feeding a meal caused a reduction in the median duodenal pH to 54 In addition, there was considerable fluctuation in the postprandial duodenal pH on an intrasubject basis The pH in the duodenum did not return to fasted state values within the 4-hr postprandial observation period There was no tendency for the duodenal pH to be related to the gastric pH in either the fed or fasted phases of the study Furthermore, pH in the upper GI tract of young, healthy subjects appears to be independent of gender The differences in upper GI pH between the fasted and the fed state are discussed in terms of dosage form performance and absorption for orally administered drugs

/pdf/upper-gastrointestinal-gi-ph-in-young-healthy-men-and-women-4k6ucxdak8.pdf

Upper gastrointestinal (GI) pH in young, healthy men and women.

https://deepblue.lib.umich.edu/bitstream/handle/2027.42/97269/1_ftp.pdf?sequence=1

Physicochemical and Physiological Mechanisms for the Effects of Food on Drug Absorption: The Role of Lipids and pH

Campylobacter pylori and duodenal ulcers: the gastrin link

We followed up 55 patients with proven primary biliary cirrhosis for several years or until death. A graph of the level of serum bilirubin versus time that was constructed for each patient shows an initial period of variable length in which the serum bilirubin level remained constant. This was followed by a period of rapid rise in serum bilirubin which culminated in the patient's death. Whenever two successive serum bilirubin values taken six months apart exceeded 34 mumol/l (2.0 mg/dl) the patient had entered a late phase of disease and lived an average of 49 months. Ninety-five per cent confidence limits on survival time were 32-74 months. If two successive six month bilirubin values exceeded 102 mumol/l (6.0 mg/dl), calculated survival time was 25 months, and if two successive six month bilirubin values exceeded 170 mumol/l (10.0 mg/dl), survival time was 17 months. Fifteen of the 41 living patients had two consecutive serum bilirubin levels greater than 34 mumol/l (2.0 mg/dl). However, the slope of the rising bilirubin in the living patients is only 35 mumol/l/yr (1.5 mg/dl/yr) compared with 42 mumol/l/yr (2.5 mg/dl/yr) in the dead patients. This means that patients with this disease not may be living considerably longer.

https://gut.bmj.com/content/gutjnl/20/2/137.full.pdf

Serum bilirubin: a prognostic factor in primary biliary cirrhosis.

Effect of Helicobacter pylori on gastric somatostatin in duodenal ulcer disease.

Gastric secretion and emptying after ordinary meals in duodenal ulcer.

https://www.gastrojournal.org/article/S0016-5085(77)80012-7/pdf

Timothy B. Deering

Papers

Gastric secretion and emptying after ordinary meals in duodenal ulcer.

Effect of d-Penicillamine on Copper Retention in Patients with Primary Biliary Cirrhosis

Comparison of an H2 receptor antagonist and a neutralizing antacid on postprandial acid delivery into the duodenum in patients with duodenal ulcer.

Fate of Oral Neutralizing Antacid and Its Effect on Postprandial Gastric Secretion and Emptying