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Unabsorbed carbohydrates are fermented by colonic bacteria to short chain fatty acids (SCFA) which are rapidly absorbed, salvaging energy and reducing stool output. There are marked differences between the faecal flora and SCFA of breast fed (BF) and formula fed (FF) infants which may be related to the higher incidence of diarrhoea in FF infants. Part of this effect may be caused by a difference in the ability of the microflora to ferment carbohydrate. To test the hypothesis that BF and FF have different fermentation capacities for simple and complex carbohydrates, in vitro cultures of faeces from healthy infants (2-10 weeks; 11 BF, 11 FF) containing glucose, lactose, raftilose (a fructo-oligosaccharide), or soybean polysaccharide were incubated anaerobically. Results were compared with those of adult faecal cultures using the same carbohydrates. Cultures of faeces from BF and FF infants produced comparable amounts of total SCFA in all cultures. These cultures produced less SCFA than those from adult faeces and produced very little SCFA from complex carbohydrate. BF cultures produced more acetic acid than FF in all cultures, whereas FF cultures produced more propionate with sugars and more butyrate with raftilose. Both groups of infants produced less butyrate than adults in all cultures. Thus it is unlikely that a lower ability to ferment carbohydrate is a major cause of increased risk of diarrhoea in FF fed infants but individual SCFA production may be important. 相似文献
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Regional infusion of urokinase into occluded lower-extremity bypass grafts: long-term clinical results 总被引:1,自引:0,他引:1
Durham JD; Geller SC; Abbott WM; Shapiro H; Waltman AC; Walker TG; Brewster DC; Athanasoulis CA 《Radiology》1989,172(1):83-87
The initial outcome, long-term patency rate, and rate of limb salvage were studied in patients after regional urokinase infusion for treatment of thrombosed lower-extremity grafts. Seventy-one infusions were performed in 53 patients. Complete clot lysis occurred in 75% of grafts, with establishment of antegrade blood flow in 66%. Variables that favorably influenced clot lysis and the reestablishment of antegrade blood flow through the graft were a short duration of occlusion and a suprainguinal graft position. The median duration of patency after infusion and adjunctive therapy was 162 days, with 75% limb salvage at 301 days. No statistically significant variables that influenced the length of patency were identified. These long-term patency results are inferior to the reported results in suprainguinal grafts after reoperation. They appear similar to reported results for occluded infrainguinal grafts treated with thrombectomy and patch grafting. 相似文献
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Kelsey CA; Lane RG; Moseley RD; Mettler FA; Rosenberg RD; Williams AG; Garcia JF; Feldman BS; Boardman RE 《Radiology》1986,159(3):653-655
The effectiveness of a shaped filter in improving nodule and infiltrate detection was measured by observer performance testing. Seven observers read 152 test radiographs of the chest obtained from human volunteers. Half the test radiographs had target images. Observer performance in detecting nodule or infiltrate images was compared with the shaped-filter system and with a conventional chest imaging system. The results were analyzed using receiver operating characteristic (ROC) techniques and indicate that the filter technique was not significantly different from the conventional technique in infiltrate depiction. Observer performance in detecting nodules was slightly worse on images obtained with the shaped-filter system. 相似文献