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51.
Felipe A. Calvo David Ortiz de Urbina Luis Sierrasesúmaga Oscar Abuchaibe Ignacio Azinovic Federico Antillon Manuel Santos Jos Canadell 《Pediatric blood & cancer》1991,19(6):478-485
From September 1984 to December 1989, 38 patients of pediatric age with localized bone sarcomas received intraoperative radiotherapy (IORT) as part of a multidisci plinary treatment program. The age ranged from 6 to 21 years. The tumor histologies were 22 osteosarcomas and 16 Ewing's sarcomas. Thirty-four had initial primary disease (90%) and 4 were treated for local recurrence (10%). IORT was used on 32 untreated patients and in 6 previously treated with external beam radiotherapy (EBR). The IORT field included the surgically exposed tumor bed area. Single radiation doses ranging from 10 to 20 Gy were delivered, using 6–20 MeV electron beams. The median follow-up time for the entire group is 25 months (2–65+ months). The projected 5-year disease-free and overall survival rates are 65% and 69%, respectively. One patient developed a local recurrence in each histological group: one chondroblastic osteosarcoma and one cervical Ewing's sarcoma. Six patients died from metastatic progression: 3 initially recurrent tumors and three primary disease cases. Severe neuropathy and soft tissue necrosis were seen in some patients as IORT related complications. IORT is a feasible technique to be integrated in multidisciplinary programs that may promote local control in pediatric and adolescent patients with bone sarcomas. Peripheral nerves are dose-limiting tissue structures for IORT. 相似文献
52.
L. Muntaner J. J. Pérez-Ferrón M. Herrera J. Rosell D. Taboada S. Climent 《Neuroradiology》1997,39(8):605-608
Focal abnormalities of gyration (FAG) are developmental disorders that may occur in isolated patients or, as in the case
being reported, as part of a familial disorder. Analysis of individuals in a family spanning three generations was carried
out using MRI. Abnormalities, present in all members of generations II and III, included focal cortical dysplasia (three patients),
focal cortical infolding (two patients) and schizencephaly (one patient); associated minor anomalies, such as white matter
abnormalities, were seen in the remaining three members of generations II and III. MRI recognition of FAG in the family being
reported proved useful in defining their phenotypical expression and providing proper counselling for individual family members.
Received: 22 August 1996 Accepted: 7 October 1996 相似文献
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57.
Manuel Diaz-Llopis Salvador García-Delpech David Salom Patricia Udaondo Francisco Bosch-Morell Arturo Quijada Francisco J Romero Luis Amselem 《Journal of ocular pharmacology and therapeutics》2007,23(4):343-350
PURPOSE: The aim of this study to analyze the preventive effect of high-dose infliximab in endotoxin-induced uveitis (EIU) in rabbits. METHODS: An experimental study was conducted on 64 rabbits. Salmonella typhimurium lipopolysaccharide endotoxin was intravitreally injected. Infliximab was intravenously (i.v.) injected 24 h before the intravitreal injection (20 mg/kg). The animals were randomly assigned to five groups: group A, saline intravitreal injection; group B, Infliximab i.v. group C, infliximab + saline; group D, intravitreal endotoxin and group E, infliximab i.v. + intravitreal endotoxin. With two masked observers, a microscopic examination of aqueous humor (cells, tumor necrosis factor [TNF] alpha) and aqueous protein level were performed 24 h after an endotoxin injection and 48 h after an infliximab infusion. RESULTS: Infliximab treatment, at a dose of 20 mg/kg, significantly improved all the parameters. Inflammatory cell infiltration was significantly reduced in the iris, ciliary body, and anterior chamber (U Mann-Whitney test, P = 0.01). Associated with a lower level of TNF-alpha and protein exudate in aqueous humor (U Mann-Whitney test, P = 0.01). CONCLUSIONS: Infliximab, at a dose of 20 mg/kg, is effective in the prophylaxis of the EIU. 相似文献
58.
Melissa Hurwitz Manuel G Garcia Robert L Poole John A Kerner 《Nutrition in clinical practice》2004,19(3):305-308
The standard of care for patients with cholestasis (direct bilirubin >or=2 mg/dL) while receiving parenteral nutrition (PN) solutions is to reduce or discontinue the copper and manganese. The repercussions of this action have not been studied. Two adult case reports document low serum copper levels associated with clinical symptoms of copper deficiency after the removal of copper from their PN solutions. We now describe the first known series of pediatric patients to develop copper deficiency after copper was removed from their PN solutions. 相似文献
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David D. Dean Zvi Schwartz Ofelia E. Muniz Ruben Gomez Larry D. Swain David S. Howell Barbara D. Boyan 《Calcified tissue international》1992,50(4):342-349
Summary This study examined the presence of extracellular matrix processing enzymes in matrix vesicles produced by rat costochondral resting zone and growth zone chondrocytes in culture. Optimum procedures for the extraction of each enzyme activity were determined. Enzyme activity associated with chondrocyte plasma membrane microsomes was used for comparison. There was a differential distribution of the enzyme activities related to the cartilage zone from which the cells were isolated. Acid and neutral metalloproteinase (TIMP), plasminogen activator, and betaglucuronidase were highest in the growth zone chondrocyte (GC) membrane fractions when compared with matrix vesicles and plasma membranes isolated from resting zone chondrocyte (RC) cultures. There was a threefold enrichment of total and active acid metalloproteinase in GC matrix vesicles, whereas no enrichment in enzyme activity was observed in RC matrix vesicles. Total and active neutral metalloproteinase were similarly enriched twofold in GC matrix vesicles. TIMP, plasminogen activator, and betaglucuronidase activities were highest in the plasma membranes of both cell types. No collagenase, lysozyme, or hyaluronidase activity was found in any of the membrane fractions. The data indicate that matrix vesicles are selectively enriched in enzymes which degrade proteoglycans. The highest concentrations of these enzymes are found in matrix vesicles produced by growth zone chondrocytes, suggesting that this may be a mechanism by which the more differentiated cell modulates the matrix for calcification. 相似文献