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41.
Several outbreaks of varicella have occurred among refugees. We aimed to estimate the prevalence of varicella susceptibility among refugees, and identify risk factors for varicella susceptibility. All refugees rostered at Crossroads Clinic in Toronto, Canada in 2011–2014 were included in our study. Varicella serology was assessed at the initial visit. Refugees’ age, sex, education, time since arrival, and climate and population density of birth country were abstracted from the chart. Multivariate logistic regression was used to identify risk factors for varicella susceptibility. 1063 refugees were rostered at Crossroads Clinic during the study; 7.9 % (95 % CI 6.1, 9.7) were susceptible to varicella. Tropical climate (OR 3.20, 95 % CI 1.53, 6.69) and younger age (ORper year of age 0.92, 95 % CI 0.88–0.96) were associated with increased varicella susceptibility. These risk factors for varicella susceptibility should be taken into account to maximize the cost-effectiveness of varicella prevention strategies among refugees.  相似文献   
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We have evaluated the fibrinogen/fibrin fragment E antigen assay as a diagnostic test in patients with clinically suspected venous thrombosis by comparing the results of this assay with venography in 272 patients. The result of the fragment E antigen assay was elevated in 79 of 80 patients with positive venograms for recent venous thrombosis (sensitivity 99%) and within the normal range in 161 of 192 patients with normal venograms (specificity 84%). The fragment E assay was also evaluated in 130 medical and surgical controls without evidence of venous thrombosis by leg scanning and the test was found to be relatively nonspecific. However, in the patient group under study, a correct clinical diagnosis of no thrombosis, based on a normal fragment E result, was made in 161 of 162 cases (negative predictive value of 99%). Therefore, a normal test result effectively excludes a diagnosis of venous thrombosis in clinically symptomatic patients. The assay, as currently performed, is technically demanding and takes 24 hr to complete. Therefore, it will have to be simplified before it can be applied to clinical practice.  相似文献   
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Objectives

Widespread use of β-lactam antibiotics could cause resistance to this group of antibiotics in pathogenic bacteria through the production of the enzyme β-lactamases. The aim of this study is to determine the molecular detection of AmpC β-lactamases among clinical Escherichia coli isolated from Ilam hospitals in Ilam, Iran.

Methods

One hundred and twelve clinical isolates of E. coli were collected from hospitalized patients and were identified by biochemical tests. They were evaluated for extended spectrum beta-lactamases (ESBLs) production, and the positive strains were subjected to AmpC enzymes; for detection of AmpC cluster genes, multiplex polymerase chain reaction was applied.

Results

The analysis showed 62.5% of isolates were ESBLs positive and that five strains revealed the AmpC cluster genes. This is the first report of FOXM cluster genes in E. coli in Iran.

Conclusion

Based on our results, the prevalence of AmpC β-lactamases is increasing in Iran, which caused failure in antibiotic therapy. So, the current study recommended the revision of antibiotic policy in Iranian hospitals.  相似文献   
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Recently, nanosized metal-oxides have been extensively investigated for their ability to remove metal ions from aqueous media. However, the activity and capacity of these nanosized metal-oxides for removing metal ions decrease owing to their agglomeration in aqueous media. Herein, we synthesized a highly stable and magnetically separable rosin-biochar-coated (RBC) TiO2@C nanocomposite through a facile and environment-friendly wet chemical coating process, followed by a one-step heating route (pyrolysis) for efficient removal of Cr(vi) from aqueous solution. An array of techniques, namely, TEM, HRTEM, TEM-EDS, XRD, FTIR, VSM, BET and TGA, were used to characterize the prepared nanocomposite. The pyrolysis of rosin into biochar and the fabrication of Fe onto the RBC-TiO2@C nanocomposite were confirmed by FTIR and XRD examination, respectively. Moreover, TEM and HRTEM images and elemental mapping using TEM-EDS showed good dispersion of iron and carbon on the surface of the RBC-TiO2@C nanocomposite. Sorption of Cr(vi) ions on the surface of the RBC-TiO2@C nanocomposite was very fast and efficient, having a removal efficiency of ∼95% within the 1st minute of reaction. Furthermore, thermodynamic analysis showed negative values of Gibb''s free energy at all five temperatures, indicating that the adsorption of Cr(vi) ions on the RBC-TiO2@C nanocomposite was favorable and spontaneous. Conclusively, our results indicate that the RBC-TiO2@C nanocomposite can be used for efficient removal of Cr(vi) from aqueous media due to its novel synthesis and extraordinary adsorption efficacy during a short time period.

A biochar-coated RBC-TiO2@C nanocomposite was synthesized using a wet chemical coating followed by a one-step heating route (pyrolysis) for the efficient removal of Cr(vi).  相似文献   
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Folate is a vitamin B‐related substance needed by expectant mothers during the period right before and after conception (peri‐conceptional period) to help protect foetuses against neural tube defects (NTDs). Despite efforts to promote the peri‐conceptional uptake of folic acid (FA), adherence remains low. The aim of this study was to assess the prevalence and determinants of peri‐conceptional FA uptake among childbearing women in northern Ghana. In a cross‐sectional study, data from 303 women accessing antenatal care services in the Upper East Region of Ghana between February and July 2017 were collected and analysed in Stata (Version 12.1). Chi‐square and logistic regression analysis were used to identify the independent determinants of peri‐conceptional uptake of FA. The mean age of the study population was 27.4 (±5.73) years. The prevalence of uptake of peri‐conceptional FA was 28.7% (95% confidence interval: 26.7%‐34.2%); 66% of the women were aware of FA and 52% had acceptable knowledge about FA. Initiating ANC after 3 months of pregnancy was associated with 91% less chance of peri‐conceptional FA use [adjusted odds ratio (AOR) 0.09; 95% confidence interval (CI) 0.04‐0.22; P < .001]. Not knowing the frequency of dosing of FA was associated with a 58% less likelihood of uptake of peri‐conceptional FA (AOR 0.42; 95% CI 0.23‐0.76; P = .004). There is low uptake of peri‐conceptional FA among women of childbearing age accessing antenatal services in Northern Ghana, and this uptake is determined by the time of initiation of ANC visit and knowledge of dosage regimen of FA.  相似文献   
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