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31.
Hosein Dalili Mahdi Sheikh Amir Kamal Hardani Firouzeh Nili Mamak Shariat Fatemeh Nayeri 《PloS one》2016,11(2)
Objectives
Assessing the value of the Combined-Apgar score in predicting neonatal mortality and morbidity compared to the Conventional-Apgar.Methods
This prospective cohort study evaluated 942 neonates (166 very preterm, 233 near term, and 543 term) admitted to a tertiary referral hospital. At 1- and 5-minutes after delivery, the Conventional and Combined Apgar scores were recorded. The neonates were followed, and the following information was recorded: the occurrence of severe hyperbilirubinemia requiring medical intervention, the requirement for mechanical ventilation, the occurrence of intraventricular hemorrhage (IVH), and neonatal mortality.Results
Before adjusting for the potential confounders, a low Conventional (<7) or Combined (<10) Apgar score at 5-minutes was associated with adverse neonatal outcomes. However, after adjustment for the gestational age, birth weight and the requirement for neonatal resuscitation in the delivery room, a depressed 5-minute Conventional-Apgar score lost its significant associations with all the measured adverse outcomes; after the adjustments, a low 5-minute Combined-Apgar score remained significantly associated with the requirement for mechanical ventilation (OR,18.61; 95%CI,6.75–51.29), IVH (OR,4.8; 95%CI,1.91–12.01), and neonatal mortality (OR,20.22; 95%CI,4.22–96.88). Additionally, using Receiver Operating Characteristics (ROC) curves, the area under the curve was higher for the Combined-Apgar than the Conventional-Apgar for the prediction of neonatal mortality and the measured morbidities among all the admitted neonates and their gestational age subgroups.Conclusions
The newly proposed Combined-Apgar score can be a good predictor of neonatal mortality and morbidity in the admitted neonates, regardless of their gestational age and resuscitation status. It is also superior to the Conventional-Apgar in predicting adverse neonatal outcomes in very preterm, near term and term neonates. 相似文献32.
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The activity of membrane-bound Na+,K+-ATPase was used as a metabolic probe to study the effects of morphine in vivo in rat brain synaptosomes. Arrhenius plots were generated to study an induced perturbation within the membrane. In acute studies 0.5-h postmorphine, the drug was without effect on the basal activity of the enzyme. With dopamine-stimulated Na+,K+-ATPase morphine decreased the apparent transition temperature and specific activity of the enzyme while there was a slight stimulation in its activation energy. An increase in these parameters was observed in samples taken from animals withdrawn from the drug for 48 h. These results strongly suggest the possible involvement of the membrane phospholipids as transducer which mediates the observed biphasic effect of the drug on enzyme activity. 相似文献
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Manije Beigi Fatemeh Afarande Hosein Ghiasi 《Reports of Practical Oncology and Radiotherapy》2016,21(1):42-49
Aim
The aim of this study was to compare two bunkers designed by only protocols recommendations and Monte Carlo (MC) based upon data derived for an 18 MV Varian 2100Clinac accelerator.Background
High energy radiation therapy is associated with fast and thermal photoneutrons. Adequate shielding against the contaminant neutron has been recommended by IAEA and NCRP new protocols.Materials and methods
The latest protocols released by the IAEA (safety report No. 47) and NCRP report No. 151 were used for the bunker designing calculations. MC method based upon data was also derived. Two bunkers using protocols and MC upon data were designed and discussed.Results
From designed door''s thickness, the door designed by the MC simulation and Wu–McGinley analytical method was closer in both BPE and lead thickness. In the case of the primary and secondary barriers, MC simulation resulted in 440.11 mm for the ordinary concrete, total concrete thickness of 1709 mm was required. Calculating the same parameters value with the recommended analytical methods resulted in 1762 mm for the required thickness using 445 mm as recommended by TVL for the concrete. Additionally, for the secondary barrier the thickness of 752.05 mm was obtained.Conclusion
Our results showed MC simulation and the followed protocols recommendations in dose calculation are in good agreement in the radiation contamination dose calculation. Difference between the two analytical and MC simulation methods revealed that the application of only one method for the bunker design may lead to underestimation or overestimation in dose and shielding calculations. 相似文献36.
An extracellular source of heme can induce a significant heme oxygenase mediated relaxation in the rat aorta 总被引:2,自引:0,他引:2
Hosein S Marks GS Brien JF McLaughlin BE Nakatsu K 《Canadian journal of physiology and pharmacology》2002,80(8):761-765
Carbon monoxide has been under active investigation for a role in controlling vascular tone throughout the last decade because of its ability to induce relaxation in blood vessels. The underlying mechanisms of this response are hypothesized to be mediated by soluble guanylyl cyclase (sGC) and, in some instances, KCa channels. The major source of CO in major blood vessels is the catabolic process of heme degradation, which is catalyzed by heme oxygenase (HO). This heme substrate could be derived from heme sources within vascular smooth muscle cells, such as heme proteins, or by uptake from the extracellular milieu. The current study shows that the isolated rat aorta relaxes upon exposure to pharmacological concentrations of heme in the bathing medium. This response was inhibited by an inhibitor of HO (tin protoporphyrin) and sGC (1-H-[1,2,4]-oxadiazolo[4,3-a]quinoxalin-1-one). These observations were interpreted to mean that vascular smooth muscle cells are capable of taking up and utilizing heme for the production of CO. 相似文献
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Chen SS Torres-Sanchez CJ Hosein N Zhang Y Lacy DB McGuinness OP 《American journal of physiology. Endocrinology and metabolism》2005,288(1):E163-E170
In response to chronic (5 days) TPN, the liver becomes a major site of glucose disposal, removing approximately 45% (4.5 mg.kg(-1).min(-1)) of exogenous glucose. Moreover, approximately 70% of glucose is not stored but released as lactate. We aimed to determine in chronically catheterized conscious dogs the time course of adaptation to TPN and the glycogen depletion impact on early time course. After an 18-h (n = 5) fast, TPN was infused into the inferior vena cava for 8 (n = 5) or 24 h (n = 6). A third group, of 42-h-fasted animals (n = 6), was infused with TPN for 8 h. TPN was infused at a rate designed to match the dog's calculated basal energy and nitrogen requirements. NHGU (-2.3 +/- 0.1 to 2.2 +/- 0.7 to 3.9 +/- 0.6 vs. -1.7 +/- 0.3 to 1.1 +/- 0.5 to 2.9 +/- 0.4 mg.kg(-1).min(-1), basal to 4 to 8 h, 18 vs. 42 h) and net hepatic lactate release (0.7 +/- 0.3 to 0.6 +/- 0.1 to 1.4 +/- 0.2 vs. -0.6 +/- 0.1 to 0.1 +/- 0.1 to 0.8 +/- 0.1 mg.kg(-1).min(-1), basal to 4 to 8 h) increased progressively. Net hepatic glycogen repletion and tracer determined that glycogen syntheses were similar. After 24 h of TPN, NHGU (5.4 +/- 0.6 mg.kg(-1).min(-1)) and net hepatic lactate release (2.6 +/- 0.4 mg.kg(-1).min(-1)) increased further. In summary, 1) most hepatic adaptation to TPN occurs within 24 h after initiation of TPN, and 2) prior glycogen depletion does not augment hepatic adaptation rate. 相似文献