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We evaluated the response to the recombinant Hepatitis B vaccine using an accelerated schedule versus the traditional schedule by studying the immunologic memory induced in 200 children with HBs-Ag negative mothers. At seroconversion, the traditional schedule presented a higher percentage of children with serum HBs-Ag concentrations over 100 mIU/ml than the accelerated schedule. After five years this difference was no longer statistically significant and children who presented anti-HBsAg concentrations below 10 mUI/ml received an additional booster dose which stimulated the antibody concentration to exceed 100 mIU/ml in all cases. Recombinant HBV vaccine induced better long term immunologic memory when it was administered earlier.  相似文献   
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In 20 healthy premature infants, 10 of whom were administered a total dose of 120 mg/kg vitamin E intramuscularly during the first 13 days after birth, polymorphonuclear leukocyte (PMN) bactericidal activity, frequency and index of phagocytosis, NBT reduction, random movement, chemotaxis and metabolic activity were evaluated within the first 48 hours and again at 5, 14 and 30 days of age. PMN function was also assessed in 30 adult controls. In the treated and untreated infants no differences were found in PMN function before treatment with vitamin E; however phagocytosis, bactericidal activity and chemotaxis were significantly lower than in the adult controls. At 5 days of age, in the untreated infants both index and frequency of phagocytosis remained low but in the treated groups increased significantly. At 14 and 30 days phagocytosis was normal in both treated and untreated infants. No differences were found in the bactericidal activity, NBT reduction, random movement, chemotaxis or metabolic activity of the treated and untreated infants at the ages studied. This preliminary report suggests that vitamin E may be used in premature newborns for accelerating normalization of phagocytic function in the neonatal period.  相似文献   
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We measured cell surface expression of CD34, HLA-DR, CD38, CD19, CD33, CD71, and CD45 antigens in the hematopoietic progenitor cells of fetal cord blood to investigate immunophenotypic changes at different gestational ages. These antigens were identified by flow cytometry in 11 fetuses (gestational age 19-24 wk, in 12 preterm (25-28 wk) and in ten newborn infants born at term. The frequency and number of CD34+ cells were higher in the blood of the 11 fetuses; in addition, a statistically significant inverse correlation between number of CD34+ cells and advancing gestational age was noted. The numbers of CD34+ CD19+, CD34+ CD33+, and CD34+ CD45+ coexpressing cells were significantly higher in the fetuses, whereas CD34+ CD38+ cells were more represented in the neonates at term. Gestational age was inversely correlated with the number of CD34+ CD19+ and CD34+ CD33+ coexpressing cells. A positive correlation between gestational age and CD34+ CD38+ cells was noted. The number of CD34- CD19+, CD34- CD38+, and CD34- CD45+ cells was higher in term infants; furthermore, a significant correlation between advancing gestational age and CD34- CD38+ or CD34- CD45+ cells was demonstrated. The proliferative capacity was also higher at lower gestational ages. These data suggest that the development and lineage commitment of fetal cord blood hematopoietic progenitor cells are very active during the last two trimesters of pregnancy. The most significant changes of hematopoietic cells maturation seem to occur within 25 wk of gestation.  相似文献   
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The determinants of the degree of metabolic decompensation at the diagnosis of type 1 (insulin dependent) diabetes mellitus (IDDM) and the possible role of diabetic ketoacidosis in the preservation and recovery of residual beta cell function were examined in 745 Finnish children and adolescents. Children younger than 2 years or older than 10 years of age were found to be more susceptible to diabetic ketoacidosis than children between 2 and 10 years of age (< 2 years: 53.3%; 2-10 years: 16.9%; > 10 years: 33.3%). Children from families with poor parental educational level had ketoacidosis more often than those from families with high parental educational level (24.4% v 16.9%). A serum C peptide concentration of 0.10 nmol/l or more was associated with a favourable metabolic situation. Low serum C peptide concentrations, high requirement of exogenous insulin, low prevalence of remission, and high glycated haemoglobin concentrations were observed during the follow up in the group of probands having diabetic ketoacidosis at the diagnosis of IDDM. Thus diabetic ketoacidosis at diagnosis is related to a decreased capacity for beta cell recovery after the clinical manifestation of IDDM in children.  相似文献   
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Bacterial endocarditis is an uncommon diagnosis in childhood with significant morbidity and mortality. Aortic aneurysm as a complication is well described in adults but there are few reports in the paediatric literature. Two children with bacterial endocarditis are described, whose illnesses were complicated by aortic aneurysm formation requiring surgical intervention.  相似文献   
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Role of bacterial translocation in necrotizing enterocolitis   总被引:1,自引:0,他引:1  
The intestinal mucosa functions as a major local defense barrier preventing bacteria that colonize the gut from invading organs and tissues. Under certain circumstances, bacteria colonizing the gastrointestinal tract can cross the gut mucosal barrier to infect the mesenteric lymph node and systemic organs via a process termed bacterial translocation. Factors that promote the translocation of bacteria or endotoxin from the gut include bacterial overgrowth with gram-negative enteric bacilli, impaired host immune defenses and injury to the gut mucosa resulting in increased intestinal permeability. These same promoting factors are present in patients at increased risk of developing necrotizing enterocolitis. Consequently, this review focuses on the potential role of bacterial and endotoxin translocation from the gut in the pathogenesis of necrotizing enterocolitis.  相似文献   
40.
One hundred and twenty eight Brazilian children with lymphoblastic leukaemia were intensively treated with a Berlin-Frankfurt-Munich based protocol. More children had a white cell count above 50 x 10(9)/l (31%) then observed in developed countries. After a median follow up of 31 months (11-58 months), the estimated probability of relapse free survival was 41% (7%) for the whole group. After adjustment in the Cox's multivariate model, malnutrition was the most significant adverse factor affecting duration of complete remission. Age above 8 years and high peripheral white cell count were also significant adverse factors. Among the nutritional indices, the height for age and weight for age z scores were both significant, whether the cut off points of z-2 or z = -1.28 were chosen to define malnutrition. A strong statistical association between the two indices was found; the contribution of height for age z score to the prediction of relapse free survival was more significant. Children with height for age z score < -2 had a relapse risk of 8.2 (95% confidence interval 3.1 to 21.9) relative to children with z score > -2. The results of this study suggest that socioeconomic and nutritional factors should be considered in the prognostic evaluation of children with leukaemia in developing countries.  相似文献   
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