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91.
92.
Understanding the interaction of nanoparticles with biological fluid is important for predicting the behavior and toxicity of nanoparticles in living systems. The earthworm Eisenia andrei was exposed to citrate‐coated silver nanoparticles (cAgNPs), and the interaction of cAgNPs with earthworm coelomic fluid (ECF), the cytotoxicity of cAgNPs in earthworm coelomocytes was assessed. The neutral red retention assay showed a reduction in lysosomal stability after exposure. The toxicity of silver ions dissolved from cAgNPs in the soil medium was not significant. The aggregation and dissolution of cAgNPs increased in ECF, which contains various electrolytes that alter the properties of nanoparticles, and their subsequent toxicity. Microscopic and dissolution studies demonstrated that the aggregation of cAgNPs rapidly increased, and readily dissolved in ECF. The bioavailability of cAgNPs to earthworms induced lysosomal cytotoxicity. This is the first report to test the interaction and lysosomal cytotoxicity of nanoparticles in earthworm biofluids. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
93.
Nanostructured FeS dispersed onto N, S dual-doped carbon nanotube–graphene composite support (FeS/N,S:CNT–GR) was prepared by a simple synthetic method. Annealing an ethanol slurry of Fe precursor, thiourea, carbon nanotube, and graphene oxide at 973 K under N2 atmosphere and subsequent acid treatment produced FeS nanoparticles distributed onto the N, S-doped carbon nanotube–graphene support. The synthesized FeS/N,S:CNT–GR catalyst exhibited significantly enhanced electrochemical performance in the oxygen reduction reaction (ORR) compared with bare FeS, FeS/N,S:GR, and FeS/N,S:CNT with a small half-wave potential (0.827 V) in an alkaline electrolyte. The improved ORR performance, comparable to that of commercial Pt/C, could be attributed to synergy between the small FeS nanoparticles with a high activity and the N, S-doped carbon nanotube–graphene composite support providing high electrical conductivity, large surface area, and additional active sites.  相似文献   
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Infectious bronchitis viruses (IBVs) are evolving continuously via genetic drift and genetic recombination, making disease prevention and control difficult. In this study, we undertook genetic and pathogenic characterization of recombinant IBVs isolated from chickens in South Korea between 2003 and 2019. Phylogenetic analysis showed that 46 IBV isolates belonged to GI-19, which includes nephropathogenic IBVs. Ten isolates formed a new cluster, the genomic sequences of which were different from those of reference sequences. Recombination events in the S1 gene were identified, with putative parental strains identified as QX-like, KM91-like, and GI-15. Recombination detection methods identified three patterns (rGI-19-I, rGI-19-II, and rGI-19-III). To better understand the pathogenicity of recombinant IBVs, we compared the pathogenicity of GI-19 with that of the rGI-19s. The results suggest that rGI-19s may be more likely to cause trachea infections than GI-19, whereas rGI-19s were less pathogenic in the kidney. Additionally, the pathogenicity of rGI-19s varied according to the genotype of the major parent. These results indicate that genetic recombination between heterologous strains belonging to different genotypes has occurred, resulting in the emergence of new recombinant IBVs in South Korea.  相似文献   
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BackgroundIn order to improve organizational culture and job outcomes, it is important to characterize and better understand the relationship between aggression and verbal abuse among nurses.PurposeTo examine the relationships among demands at work, aggression, and verbal abuse among nurses.MethodsA cross-sectional study was conducted using survey data from three tertiary hospitals located in South Korea. Sixteen nursing units were selected and 378 nurses’ data were used as the final sample. The relationships were examined by multiple linear or logistic regression analyses.FindingsMore than 70% of the nurses had experienced at least 1 type of verbal abuse. Higher physical aggression and hostility were significantly related to greater verbal abuse experience.ConclusionTo prevent the vicious cycle of victims becoming perpetrators, it is necessary to develop and implement concrete strategies to manage verbal abuse and aggression among nurse colleagues.  相似文献   
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Heart failure (HF) is very common in the elderly but there are not sufficient data about the clinical characteristics and prognostic factors of HF among the Asian elderly patients. The aim of the study was to find out the clinical characteristics, survival, and prognostic factors of HF in Korean elderly patients. Among elderly patients admitted from February 1995 to February 1998, the patients with a discharge diagnosis of HF were enrolled. Through the medical record review, the diagnosis was confirmed and clinical parameters to affect survival were identified. Total number of the subjects was 104 [age: 77+/-7 years (65-96), male:female=36:68, follow-up duration: 20+/-14 months, LVEF: 46+/-16%]. Ischemic heart disease (IHD) was the most common cause of HF (42%) followed by valvular heart disease (28%), and hypertension (20%). The 1-year survival rate was 71.3%. Advanced age [risk ratio (RR): 1.41 per 5 years of age; 95% CI: 1.11-1.80] and reduced left ventricular ejection fraction (0.69 per 10%, 0.52-0.93), poor initial functional class (2.40, 1.15-5.00), diabetes (2.79, 1.30-5.97) and past history of HF (2.37, 1.10-5.10) badly affected the survival rates. When the Cox proportional hazard model was applied for multivariate analysis, only aging (1.64 per 5 years of age, 1.19-2.28) and diabetes (4.92, 1.83-13.23) predicted poor prognosis. Twenty-seven percent of the patients had diastolic HF (LVEF>45%, LVEDD<55 mm) who had higher survival rates with marginal significance (0.35, 0.10-1.17, P=0.09).  相似文献   
100.

Purpose:

This feasibility study was designed to examine if remote communication technology can be used in the technical training of an insulin pump in adults with diabetes who were familiar with insulin pump therapy.

Methods:

Surveys were emailed to 69 individuals who purchased an insulin pump and had been trained by the manufacturer’s diabetes educators. In consultation with providers, participants were given the choice of receiving training in a face-to-face meeting or via remote communication technology. The survey consisted of 27 questions asking participants’ characteristics, device proficiency, confidence, and their satisfaction with the insulin pump and the training method. Differences between the 2 groups were examined using bivariate analyses.

Results:

There were 17 participants in the remote group and 20 participants in the face-to-face group. Participants had a mean age of 40.9 ± 14.3 years, had diabetes for 24.3 ± 13.8 years, and used an insulin pump for 9.8 ± 4.9 years. The participants in both groups were not statistically different in age, diabetes history, years on insulin pump, device proficiency, confidence, or satisfaction with the training method. The remote group reported less graduate-level education (P < .05) and higher satisfaction scores with the insulin pump training (P < .05).

Conclusion:

Although this study has limitations associated with the small sample size and self-selection bias, the results suggest that remote communication technology may be an effective tool to provide technical training to adults who are familiar with insulin pump therapy. Additional research is required to determine the effectiveness of the remote insulin pump training.  相似文献   
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