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The distal jet simplified and updated   总被引:2,自引:0,他引:2  
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Background  

To gain insight into factors that might affect results of future case-control studies, we performed an analysis of children with sepsis and purpura admitted to the paediatric intensive care unit (PICU) of Erasmus MC-Sophia Children's Hospital (Rotterdam, The Netherlands).  相似文献   
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BACKGROUND: The elderly are characterized by a high prevalence of chronic heart failure (CHF) and frailty, which is a complex interaction of physical, psychological and social impairment. This study aimed to examine the predictive role of frailty on long-term mortality in elderly subjects with CHF. MATERIALS AND METHODS: The study assessed long-term mortality after 12-year follow up in 120 subjects with CHF and 1139 subjects without CHF, selected in 1992, from a random sample of the elderly population in the Campania region of Italy. Frailty was assessed according to a 'Frailty Staging System'. RESULTS: Subjects with CHF were prevalently female (60%) and older than 75 years (mean 75.9 +/- 6.7); subjects without CHF were prevalently female (56.4%) and younger than 75 years (mean 74.0 +/- 6.3). In subjects with and without CHF stratified into classes of frailty there was a statistically significant increase in age, comorbidity, disability and low social support, and a decrease in MMSE score. Moreover, death progressively increased more with frailty in subjects (70.0% to 94.4%, P < 0.03) than in those without (43.8.% to 88.3%, P < 0.0001) CHF. The Kaplan-Meier analysis shows that at 9 years the probability of survival progressively decreased as frailty increased (45.5% to 0%) in subjects with CHF and from 62.8% to 25.9% in subjects without CHF. The Cox regression analysis indicated that frailty is predictive of mortality in the multivariate model adjusted for several variables including sex and age in subjects with and without CHF. Moreover, the analysis showed that frailty is more predictive of mortality in elderly subjects with CHF when it was analyzed either as continuous (1.48 vs. 1.36) or as a dummy (3 vs. 1 = 1.62 vs. 1.24) variable. CONCLUSIONS: Thus mortality among elderly subjects with or without CHF increases with frailty. Moreover, frailty is more predictive of long-term mortality in elderly subjects with than in those without CHF. Hence, frailty represents a new independent variable for predicting long-term mortality in elderly subjects with CHF.  相似文献   
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Possible mechanisms of valproate in migraine prophylaxis   总被引:7,自引:0,他引:7  
Valproate has been shown to be an effective prophylactic treatment in migraine. Investigation of the mechanism of its antimigraine action is difficult due to the broad range of its biochemical effects and the complex nature of migraine pathophysiology. Valproate increases brain GABA levels and, in doing so, may suppress migraine-related events in the cortex, perivascular parasympathetics or trigeminal nucleus caudalis. There is experimental evidence that it suppresses neurogenic inflammation and directly attenuates nociceptive neurotransmission. In addition, valproate reportedly alters levels of excitatory and inhibitory neurotransmitters and exerts direct effects on neuronal membranes in vitro. Valproate's observed effect may ultimately result from a combination of actions at different loci.  相似文献   
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The G gamma and A gamma content of Hb F produced in cultures of BFU-Es from the blood of normal fetuses, neonates, and adults was determined. The results show that erythroid progenitors produce A gamma and G gamma chains in a ratio characteristic of their ontogenic stage. The analysis of the G gamma/A gamma ratio in culture of BRU-Es from thalassemic patients showed a marked heterogeneity, resembling that observed in freshly drawn cells. These results afford evidence that the type of gamma chain produced is programmed at the level of early erythroid progenitors.  相似文献   
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