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61.
Chiam-Wen Liew  S. Ramesh 《Materials》2014,7(5):4019-4033
Two different ionic liquid-based biopolymer electrolyte systems were prepared using a solution casting technique. Corn starch and lithium hexafluorophosphate (LiPF6) were employed as polymer and salt, respectively. Additionally, two different counteranions of ionic liquids, viz. 1-butyl-3-methylimidazolium hexafluorophosphate (BmImPF6) and 1-butyl-3-methylimidazolium trifluoromethanesulfonate (also known as 1-butyl-3-methylimidazolium triflate) (BmImTf) were used and studied in this present work. The maximum ionic conductivities of (1.47 ± 0.02) × 10−4 and (3.21 ± 0.01) × 10−4 S·cm−1 were achieved with adulteration of 50 wt% of BmImPF6 and 80 wt% of BmImTf, respectively at ambient temperature. Activated carbon-based electrodes were prepared and used in supercapacitor fabrication. Supercapacitors were then assembled using the most conducting polymer electrolyte from each system. The electrochemical properties of the supercapacitors were then analyzed. The supercapacitor containing the triflate-based biopolymer electrolyte depicted a higher specific capacitance with a wider electrochemical stability window compared to that of the hexafluorophosphate system.  相似文献   
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ObjectiveThe purpose of this study was to identify histologic characteristics of advanced coronary atherosclerotic plaques that are related with the detection of the napkin-ring sign (NRS) in coronary CT angiography (CCTA).MethodsCCTA was performed in 7 human donor hearts. Histological slicing and stainings were performed in 1 mm increments of each major coronary artery. Histology was co-registered with the CT-data and classified according to the modified AHA classification.ResultsAdvanced plaques (types IV–VI) were present in 139 (23%) of 611 cross sections. Of these 33 (24%) demonstrated an NRS in CCTA. NRS plaques were associated with greater non-core plaque area (median 10.2 vs. 6.4 mm2, p < 0.01) and larger vessel area (median 17.1 vs. 13.0 mm2, p < 0.01). The area of the necrotic/lipid core was larger in plaques with NRS (median 1.1 vs. 0.5 mm2, p = 0.05). Angiogenesis tended to be more frequent in plaques with NRS (48% vs. 30%) whereas micro-calcifications tended to be more frequent in plaques without NRS (27% vs. 46%) (p = 0.06 and 0.07 respectively). In a multivariate analysis, necrotic/lipid core area (OR = 1.9), non-core plaque area (OR = 1.6), and total vessel area (OR = 0.9) independently predicted the appearance of the NRS in coronary CT angiography.ConclusionDelineation of NRS in CCTA is independently linked to the size of the necrotic/lipid core, the size of the non-core plaque and to the vessel area as measured in histology of advanced coronary atherosclerotic plaques.  相似文献   
64.
Background/Aims: Hepatic progenitor cells (HPCs) activation, proliferative ductular reaction (DR), replicative arrest and Notch signaling have been demonstrated in a variety of human liver diseases. The relationships are poorly understood in morbid obesity. We investigated factors responsible for the HPCs/DR, replicative arrest and Notch signaling in non-NASH and NASH groups. Methodology: Cytokeratin 7 (and 19), p21, CD34, Ki67 and different Notch receptors and ligands immunohistochemical stained biopsies from morbid obese patients with non-NASH (n=10) and NASH (n=25) were studied. These results were correlated with clinicopathological variables. Results: NASH patients presented with abnormal liver function tests and had higher HbA1c percentage. Strong association between HPCs and DR was seen (r=0.785, p<0.000). BMI, interface activity and replicative arrest were associated with HPCs expansion and DR in NASH patients. A strong association between CD34 with HPCs and DR was found in non-NASH patients. In NASH group, Notch 3 was important in bile ductular proliferation; whereas Notch 4 was associated with sinusoidal neovessels proliferation and Kupffer cell activation. Conclusions: HPCs and DR played an important role in hepatic regeneration in fatty liver disease of morbid obesity. An altered replication pathway in NASH promotes HPCs activation and DR. Notch-3 and Notch-4 were significantly different between non-NASH and NASH groups.  相似文献   
65.

Background

The increased reports of ESBL dissemination from various centres in south western, Nigeria and the recent emergence of carbapenem resistant bacteria prompted the conception of this study.

Objectives

To demonstrate the relationship between high molecular weight plasmids and the expression of antibiotic multi-resistance including ESBL and carbapenemase.

Methods

We investigated 97 isolates of selected organisms consisting of 67 E. coli and 30 Klebseilla spp for the presence of plasmids expressing ESBL including carbapenem-hydrolysing enzymes. Beta-lactamase was determined using acidometric method, while ESBL and carbapenemase activity was determined using the double-disk diffusion test as well as the Modified Hodge test (MHT). Plasmid profiles of ESBL and carbapenemase positive isolates were determined according to standard protocols.

Results

An ESBL prevalence rate of 21.6% and carbapenem- resistance rate of 9.3% was recorded. Antibiotic susceptibility profile of ESBL isolates showed 100.0% resistance against Amoxicillin, Cotrimoxazole and Erythromycin. Moderate susceptibility was recorded against the Quinolone class of antibiotics; Meropenem remained the most active antibiotic against ESBL isolates with 62.5% against E. coli and 60% against K. pneumoniae. The plasmid profiles of our study isolates ranged from 11.8kbp to 35.5kbp.

Conclusion

Due to the relationship between high molecular weight plasmids and multi-drug resistance, we hereby recommend regular molecular surveillance of this form in our study setting.  相似文献   
66.

Introduction

Perioperative scoring systems aim to predict outcome following surgery and are used in preoperative counselling to guide management and to facilitate internal or external audit. The Waterlow score is used prospectively in many UK hospitals to stratify the risk of decubitus ulcer development. The primary aim of this study was to assess the potential value of this existing scoring system in the prediction of mortality and morbidity in a general surgical and vascular cohort.

Methods

A total of 101 consecutive moderate to high risk emergency and elective surgical patients were identified through a single institution database. The preoperative Waterlow score and outcome data pertaining to that admission were collected. The discriminatory power of the Waterlow score was compared against that of the American Society of Anesthesiologists (ASA) grade and the Portsmouth Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (P-POSSUM).

Results

The inpatient mortality rate was 17% and the 30-day morbidity rate was 29%. A statistically significant association was demonstrated between the preoperative Waterlow score and inpatient mortality (p<0.0001) and 30-day morbidity (p=0.0002). Using a threshold Waterlow score of 20 to dichotomise risk, accuracies of 0.84 and 0.76 for prediction of mortality and morbidity were demonstrated. In comparison with P-POSSUM, the preoperative Waterlow score performed well on receiver operating characteristic analysis. With respect to mortality, the area under the curve was 0.81 (0.80–0.85) and for morbidity it was 0.72 (0.69–0.76). The ASA grade achieved a similar level of discrimination.

Conclusions

The Waterlow score is collected routinely by nursing staff in many hospitals and might therefore be an attractive means of predicting postoperative morbidity and mortality. It might also function to stratify perioperative risk for comparison of surgical outcome data. A prospective study comparing these risk prediction scores is required to support these findings.  相似文献   
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69.

Objective

This study seeks to examine how the extent of socioeconomic deprivation, racial and ethnic isolation, and health disadvantage differ among Medicare beneficiaries in Mississippi. Methods: Geographical information system (GIS) mappings are used in conjunction with cluster analysis to examine patterns of disparities in disease distribution, healthcare utilization and socioeconomic well-being among different counties in Mississippi.

Results

Results reveal that counties in these two clusters are markedly different in terms of socio-economic well-being but are somewhat similar in terms of disease distributions and healthcare utilization.

Conclusion

Addressing the geographic disparities in disease distribution and healthcare utilization that exist among the counties should be a public health priority. Specifically, health policies and programs should be renewed to target people living in counties that are either predominantly rural or predominantly Black or have higher percentages of population living below the poverty level.  相似文献   
70.
Objective: To evaluate whether early folic acid or multivitamin supplementation during pregnancy prevents diagnosis of hyperkinetic disorders (HKD), treatment for attention deficit hyperactivity disorder (ADHD), and ADHD-like behaviors reported by parents participating in the DNBC for children at age 7.

Methods: HKD diagnosis and ADHD medication use data were obtained from the Danish National Hospital, Central Psychiatric and Pharmaceutical registers. We estimated hazard ratios (HRs) for HKD diagnosis and ADHD medication use and risk ratios (RRs) for parent-reported ADHD behavior collected with the Strength and Difficulties Questionnaire (SDQ), comparing children whose mothers took folic acid or multivitamin supplements early in pregnancy defined as starting periconceptionally (4 weeks prior to their last menstrual period (LMP)) through 8 weeks after their LMP (4–8 weeks), to children whose mothers indicated no supplement use for the same entire period.

Results: We identified 384 children (1.1%) with a hospital diagnosis for HKD and 642 children (1.8%) treated with ADHD medication. We found no association between risk of HKD diagnosis or intake of ADHD medication and early maternal folic acid use. However, early multivitamin use was associated with an approximately 30% reduction in risk for HKD diagnosis (aHR: 0.70, 95% CI: 0.52–0.96) and 21% reduction in treatment with ADHD medication (aHR: 0.79, 95% CI: 0.62–0.98). We observed a reduced risk in parent-reported ADHD behaviors, but these results were attenuated after adjustment.

Conclusion: Our data suggest that multivitamin use in early pregnancy may reduce risk for HKD diagnosis and treatment for ADHD in the offspring.  相似文献   

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