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Evolution with age of the acetylcholinesterase activity in rectal suction biopsy in Hirschsprung's disease 总被引:5,自引:0,他引:5
The acetylcholinesterase (AChE) activity in Hirschsprung's disease was analyzed for histochemical patterns according to age. Its evolutional nature was also assessed. Two hundred thirty children (0 to 16 years of age) with acute or chronic obstipation were submitted to rectal suction biopsy for AChE histochemical staining. One hundred nineteen of them showed abnormal AChE activity. Retrospective analysis of those cases permitted us to establish three histochemical patterns: Pattern I, thick nerve trunks present only in the submucosa and, characteristically, absence of AChE activity in the lamina propria. This pattern was predominant in newborn up to 3 months of age and was designated the newborn pattern. Pattern II, thin nerve fibers in the muscularis mucosae and submucosa with a clear infiltration in the lamina propria. This pattern was mainly seen in children older than 1 year of age and was called classical pattern. Pattern III, an intermediate pattern showing morphologic characteristics of the two previous patterns with predominance of one or another, according to the age. A prospective study was also made in 15 children with Hirschsprung's disease who were submitted to suction rectal biopsies at different ages. In this study, a clear evolutional character of the AChE activity was observed from the newborn pattern to the intermediate and finally to the classical pattern. 相似文献
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Normal and diseased isolated lungs: high-resolution CT 总被引:8,自引:0,他引:8
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The adhesion of hematopoietic progenitor cells to bone marrow stromal cells is critical to hematopoiesis and involves multiple effector molecules. Stromal cell molecules that participate in this interaction were sought by analyzing the detergent-soluble membrane proteins of GBI/6 stromal cells that could be adsorbed by intact FDCP-1 progenitor cells. A single-chain protein from GBI/6 cells having an apparent molecular weight of 37 Kd was selectively adsorbed by FDCP-1 cells. This protein, designated p37, could be surface-radiolabeled and thus appeared to be exposed on the cell membrane. An apparently identical 37- Kd protein was expressed by three stromal cell lines, by Swiss 3T3 fibroblastic cells, and by FDCP-1 and FDCP-2 progenitor cells. p37 was selectively adsorbed from membrane lysates by a variety of murine hematopoietic cells, including erythrocytes, but not by human erythrocytes. Binding of p37 to cells was calcium-dependent, and was not affected by inhibitors of the hematopoietic homing receptor or the cell-binding or heparin-binding functions of fibronectin. It is proposed that p37 may be a novel adhesive molecule expressed on the surface of a variety of hematopoietic cells that could participate in both homotypic and heterotypic interactions of stromal and progenitor cells. 相似文献
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Total gastric transposition was performed in 21 children as an alternative procedure for esophageal replacement. The age at the operation ranged from 15 months to 11 years. Half of the children were less than 2 years old. Fifteen patients had esophageal atresia. The stomach was passed toward the neck either through the esophageal bed (6 cases, with concomitant blunt esophagectomy without thoracotomy) or the retrosternal route (15 cases). There was one death in the early postoperative period secondary to an anastomotic leak and acute mediastinitis in a case of pharyngogastric anastomosis. Three other patients developed cervical leak with spontaneous closure but this ultimately led to a late anastomotic stricture (more than 6 months) requiring endoscopic dilatation. Only one child needed more than three attempts of endoscopic dilatation. None of these patients required surgical revision. The mean follow-up was 60 months (range, 10 to 122 months). Despite bulky atonic intrathoracic stomach occurring in some children, only two patients developed regurgitation and symptoms of poor gastric emptying. There were neither early nor late respiratory problems. Excellent and good functional outcome were achieved in 85% and 15% of the patients, respectively. Two patients have not undergone a weight catch-up phase. The majority of the children have been between the 20th and 80th percentile for weight. Five children remain below the 20th and two below the 5th percentile. The remarkably low morbidity and mortality combined with satisfactory functional results indicate that the total gastric transposition is a safe and easy alternative surgical procedure for esophageal replacement in children. 相似文献
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