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51.
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   
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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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OBJECTIVES: This study was designed to explore contributions of plasma total triglycerides (TGs) and type III hyperlipidemia to the risk of premature familial coronary artery disease (CAD). BACKGROUND: Although plasma TGs are recognized as a risk factor for CAD, the independence of this association from related risk factors remains controversial. Also, the degree of CAD risk conferred by excess remnants of TG-rich lipoproteins in type III hyperlipidemia remains unclear. METHODS: We analyzed lipids by ultracentrifugation in a series of 653 cases with premature familial CAD (myocardial infarction or revascularization by age 55 years in men or age 65 years in women, with similar onset in at least one other first-degree relative) and in 1,029 control subjects. The relationship of CAD risk to various strata of plasma TGs, high-density lipoprotein (HDL) cholesterol, and type III hyperlipidemia, and interactions among these variables were examined by multiple logistic regression, adjusting for other CAD risk factors. RESULTS: The odds ratio for CAD with elevated plasma TG rose progressively to 11.4 in those with TGs 500 to 799 mg/dl (95% confidence interval 3.4 to 38.0, p < 0.0001) compared with <100 mg/dl, even after correction for HDL cholesterol, other elements of the metabolic syndrome, and other CAD risk factors. Risk of CAD associated with type III hyperlipidemia (found in 3.4% of cases) was also markedly increased independent of other risk factors (odds ratios of 5 to 10 depending on the model, all with p < 0.002). CONCLUSIONS: The association between the plasma TG level and premature familial CAD is strong, graded, and independent. Risk of CAD is also strikingly elevated with type III hyperlipidemia.  相似文献   
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Legacy AdvanTec and Sovereign WhiteStar: a wound temperature study   总被引:10,自引:0,他引:10  
PURPOSE: To assess the wound temperature of the Sovereign WhiteStar (S-WS) (AMO) and Legacy AdvanTec (L-ADV) (Alcon) phacoemulsification systems. SETTING: John A. Moran Eye Center, Health Sciences Center, University of Utah, Salt Lake City, Utah, USA. METHODS: Phacoemulsification using 20-gauge, 30-degree straight tips with the L-ADV and S-WS systems was performed in fresh cadaver eyes. The power was set at 50%, and aspiration was 12 mL/min; the L-ADV was run at 15 pulses per second (pps) and the S-WS at WS CF (6 milliseconds on, 12 milliseconds off). Temperature was measured at 5-second intervals for 60 seconds using a microthermistor placed in the wound. The phaco tip was angled 30 degrees to increase wound-tissue contact. At 10 seconds, the flow was clamped to simulate occlusion. Five runs, sleeved and unsleeved, were averaged for the phaco tip. RESULTS: The mean temperature was significantly higher with L-ADV than with S-WS (from 10 seconds on in the sleeved condition and from 5 seconds on in the unsleeved condition after the aspiration line was clamped). In 2 of 5 sleeved runs and 4 of 5 unsleeved runs, the L-ADV handpiece decreased power as the temperature increased. One run with the L-ADV with sleeve showed signs of wound burn. There were no signs of wound burn with the S-WS. The highest temperature recorded was 57.5 degrees C with the L-ADV and 38.6 degrees C with the S-WS. Power tests showed L-ADV protected the stroke length and S-WS had constant power except in air where it increased power. CONCLUSIONS: There was less increase in wound temperature over time with the S-WS than with the L-ADV system in sleeved and unsleeved simulated surgery in human eye-bank eyes. Because the ultrasound handpieces respond differently under different load scenarios, meaningful comparisons of pulsing features are difficult to create.  相似文献   
60.
We investigated the estrogen agonist/antagonist properties of the selective estrogen receptor modulators (SERMs), tamoxifen (TMX) and 4-hydroxy-tamoxifen (OHT), using an in vitro neuron model system to determine the impact of the neuroprotective and neurotrophic properties of these SERMs. Low concentrations of TMX or OHT were without effect on a marker of neuronal viability, basal release of lactate dehydrogenase (LDH), whereas high concentrations of both SERMs (2500 ng/ml) induced a significant increase in LDH, indicating the potential toxicity of both SERMs at high concentrations. Subsequent experiments revealed that subtoxic concentrations of both TMX and OHT induced significant neuroprotection against beta-amyloid(25-35)-induced toxicity; 15-20% and 10-15% (P < 0.05), respectively and also against glutamate-induced toxicity; 25-30% and 20-40% (P < 0.05 and P < 0.01), respectively. Additional in vitro experiments included analysis of neuron survival to determine whether the SERM, OHT, acted competitively or synergistically with the endogenous estrogen, 17 beta-estradiol (E2). These revealed that neuron survival following exposure to the neurotoxins beta-amyloid and excitotoxic glutamate was significantly increased in cultures treated with OHT (50 ng/ml) (10%, P < 0.01) and that the magnitude of survival was equivalent to E2 (10 ng/ml). The combined presence of OHT and E2 significantly protected against both beta-amyloid(25-35) and excitotoxic glutamate-induced neuron death (10%, P < 0.01) but was not significantly different from either OHT or E2 alone. To assess neurotrophic effects of these same SERMs, cultured neurons from brain regions involved in memory function and Alzheimer's disease were evaluated by morphological analysis of individual neurons. Results of these analyses demonstrated that TMX treatment did not significantly increase the process outgrowth or morphological complexity of cortical, hippocampal, or basal forebrain neurons. Similar analyses showed that OHT also failed to significantly increase the neuronal outgrowth of either cortical or hippocampal neurons. Results of these studies predict that TMX and OHT could exert a neuroprotective function but would not promote estrogen-dependent memory function.  相似文献   
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