Delayed gastrointestinal transit times in anorexia nervosa and bulimia nervosa.

Anorectic and bulimic patients frequently report symptoms of constipation, bloating, and abdominal pain suggestive of abnormal gastrointestinal motility or transit. However, except for studies of gastric emptying, gastrointestinal motility and transit in these eating disorders have not been investigated. Ten anorectic and 18 bulimic inpatients were compared with 10 healthy controls. Whole-gut transit was tested by the radiopaque marker technique, and mouth-to-cecum transit time was assessed by the lactulose breath test. All anorectics and 67% of bulimics complained of constipation. Whole-gut transit time was significantly delayed in both anorectics (66.6 +/- 29.6 hours) and bulimics (70.2 +/- 32.4 hours) compared with controls (38.0 +/- 19.6 hours). Mouth-to-cecum transit time also tended to be longer in anorectics (109.0 +/- 33.5 minutes) and bulimics (106.2 +/- 24.5 minutes) than in controls (84.0 +/- 27.7 minutes), but these differences were not statistically significant. Delayed transit could contribute to or perpetuate the eating disorders by (a) causing the patient to feel bloated, thereby exacerbating fear of fatness, or (b) causing rectal distention, which may reflexly inhibit gastric emptying.

Performance of the intensified electron-bombarded silicon camera tube in low-light-level television systems.

The combination of an image intensifier and a TV pickup tube incorporating the electron-bombarded silicon gain storage target is one of the more promising new sensors now available for low-light-level imaging. In this paper, the resolution vs irradiance characteristics of this sensor are predicted using the electrical parameters of the sensor and the observer requirements as derived from psychophysical experimentation. Analytically derived results, which include the obherver as an integral part of the sensory system, are shown to be in good agreement with experimentally measured results.