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991.
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Since 1975, 22 duplicated thumbs in 21 children were treated by ablation of one of the digits, elevation of a ligament and periosteal flap from the proximal bone, reduction osteotomy to narrow the widened proximal bone, centralization of the retained thumb, and stabilization of the joint by reattaching the ligament and periosteal flap. In addition to improving the cosmetic appearance by centralizing the retained thumb on the narrowed proximal bone, good joint stability was provided. Three patients had subsequent joint arthrodesis because of laxity of the contralateral collateral ligament. The procedure is preferred to the reconstruction of a single digit by using component parts of both duplicated thumbs because the described procedure is technically simpler and does not potentially interfere with physeal growth or leave a nail matrix defect.  相似文献   
993.
More changes to the American Academy of Pediatrics Recommended Immunization Schedule have occurred in the past 3 years than in the previous decade. Selection of the optimal immunization regimen is essential to forestall immunization delay. New complications to the schedule pose challenges for the care of preterm infants who are at increased risk of mortality and morbidity from vaccine-preventable diseases. This article reviews the relevant data regarding immunization of preterm infants and suggests strategies for prevention of immunization delay. Protection of preterm infants, especially for pertussis and influenza, involves not just assessing a child's vaccination status but those of other close contacts and household members.  相似文献   
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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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