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Hemoglobin-heme is variably converted to porphyrin during enterocolic transit. This intestinal converted fraction, as measured by HemoQuant, was elevated as a predictor of the occult bleeding site in 152 patients with discrete lesions. The intestinal converted fraction, expressed as the percentage of total fecal hemoglobin, was similar with upper gastrointestinal and proximal colon lesions. Within the colon, values trended downward with more distal location: means ± standard deviations were 18±14 proximal colon, 16 ±15 sigmoid, and 10±10 rectum. The amount of fecal blood also affected the intestinal converted fraction; correcting for hemoglobin concentration improved separation by site. Corrected intestinal converted fraction values were significantly lower with rectal (P< 0.0005) and sigmoid (P<0.02) lesions than with proximal colon lesions. Unfortunately, large within-site variation caused considerable overlap between sites. We conclude that the intestinal converted fraction is influenced by the site and amount of bleeding. However, its clinical utility is compromised by substantial individual differences in luminal hemoglobin metabolism.Presented in part at the Annual meeting of the American Gastroenterological Association in San Francisco in May of 1986 (Gastroenterology 90:1431, 1986).Supported by the Mayo Foundation.  相似文献   
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Bulimia nervosa is a health problem of increasing magnitude that is estimated to affect 2–5% of the American adolescent and young adult female population. Because of the magnitude of this clinical problem and because of the importance of the upper gastrointestinal tract in its expression, a intradepartmental program of health care for patients affected with the disease was initiated. Eleven consecutive symptomatic bulimic individuals have been evaluated jointly by the gastroenterology and the psychiatry departments of the University of Pittsburgh. Five of these 11 individuals were found to have clinically important upper gastrointestinal pathology including ulcerative esophagitis, erosive gastritis, duodenal ulcer, and delayed gastric emptying. These gastrointestinal conditions could have been either a result of or have contributed to the symptomatology of these five patients. These data suggest that bulimic subjects have clinically important gastroenterological disease processes that require specific diagnosis and treatment independent of the psychiatric treatment provided for the bulimic condition.This work was supported in part by grants from NIDDK AM 32556.  相似文献   
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The purpose of this study was to determine the role of alcohol-induced maternal hypothermia in the teratogenic actions of alcohol. C57BL/6J mice were administered an acute dose of alcohol (5.8 g/kg orally) or isocaloric sucrose on day 10 of gestation. One half of each group was placed for 6 hr in an incubator set at 32 degrees C and the other half was housed in the incubator at room temperature (22 degrees C). As expected, acute prenatal alcohol exposure at this time of gestation was associated with decreased birth weight and an increase in limb and kidney malformations. The significant alcohol x environmental temperature interaction on these dependent variables indicated that the teratogenic insult was not attenuated, but was in fact even greater for the 32 degrees C/alcohol group. An absence of a main effect of environmental temperature indicated that the 32 degrees C environment, per se, was not teratogenic. Thus, maternal hypothermia is probably not an etiological factor in animal models of fetal alcohol syndrome. Moreover, antagonism of alcohol-induced maternal hypothermia exacerbates the teratogenic actions of alcohol observed at room temperature.  相似文献   
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