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Coated activated charcoal haemoperfusion (CAC‐HP) does not reduce the plasma concentration in amitriptyline (AT)‐poisoned pigs. The aim of this non‐blinded, randomized, controlled animal trial was to determine if CAC‐HP reduces the pathological ECG changes caused by AT poisoning. Fourteen female Danish Landrace pigs (mean weight 27.7 kg, range 20–35 kg (CAC‐HP) and 24.4 kg, range 18–30 kg (control group, CG), n = 7 in each group) were included. After randomization, the pigs were anaesthetized and intravenously poisoned with AT. The intervention group underwent 4 hr of CAC‐HP plus standard care (oral activated charcoal). Intervention was compared to standard care alone. From each pig, a 12‐lead ECG and haemodynamic variables were obtained at baseline, at full AT loading dose, before and during CAC‐HP. Baseline ECG variables (RR, PR, QRS, QTc, QTp, QTe, TpTe and TpTe/QT) for lead II, v2 and v5 were not significantly different (F = 0.035–0.297, p‐values 0.421–0.919). Differences within groups over time and between groups were tested by anova repeated measures. For all variables, the time‐plus‐group level of significance revealed a p‐value > 0.05. Severe cardiovascular arrhythmias occurred in both groups with 3 in the CAC‐HP group versus 1 incident with premature death in the CG. The attenuating effect of CAC‐HP to orally instilled activated charcoal alone on AT‐induced ECG alterations did not differ significantly. We conclude that the use of modern CAC‐HP as an adjunctive treatment modality in AT‐poisoned pigs is inadequate.  相似文献   
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Purpose

Potential roles of inherited and environmental risk factors in pathogenesis of Langerhans cell histiocytosis (LCH), a myeloid neoplastic disorder, are undefined. We therefore evaluated the role of parental and perinatal factors on the risk of this childhood cancer.

Methods

Information on LCH cases (n = 162) for the period 1995–2011 was obtained from the Texas Cancer Registry. Birth certificate controls were frequency-matched on year of birth at a ratio of 10:1 for the same period. Variables evaluated included parental age, race/ethnicity, size for gestational age, and birth order. Logistic regression was used to generate an adjusted odds ratio (aOR) and 95% confidence interval (CI) testing the association between each factor and LCH.

Results

Few perinatal or parental factors were associated with LCH risk, with the exception of race/ethnicity. Mothers of Hispanic ethnicity were more likely to have children who developed LCH compared to non-Hispanic whites (aOR: 1.51; 95% CI: 1.02–2.25). This risk increased when both parents were Hispanic (aOR: 1.80; 95% CI: 1.13–2.87). Non-Hispanic black mothers were suggested as less likely to give birth to offspring who developed LCH compared to non-Hispanic whites (aOR: 0.50; 95% CI: 0.24–1.02).

Conclusions

LCH is characterized by somatic mutations in MAPK pathway genes in myeloid precursors. Increased risk for LCH in children of Hispanic parents suggests potential impact of inherited factors on LCH pathogenesis.  相似文献   
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Purpose Irreversible hydrocolloid is capable of resisting contamination by viruses and saliva when the disinfectant iodine or the disinfectant chlorhexidine is added to the water being used to mix the material. This study investigates the accuracy of alginate impressions made with water to which either of the two disinfectants has been added. Materials and Methods A total of 30 casts were made from an impression of a master cast. Ten impressions were made using water according to the manufacturer's instructions, ten were made using water to which iodine had been added, and ten were made using water to which chlorhexidine had been added. A measuring microscope was used to measure three different dimensions on each cast. Each measurement was repeated three times, and the average was used to compute the mean and standard deviation for each measured dimension. The data were statistically evaluated using a one-way analysis of variance. Results There was no statistical difference in the accuracy of irreversible hydrocolloid impressions mixed with water or with either of two disinfectant solutions. Conclusion Accurate casts can be obtained when either of the two disinfectants are incorporated into the alginate impression material.  相似文献   
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