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Ceftaroline is a new antibacterial agent that is active against the major bacterial pathogens found in acute bacterial skin and skin structure infections and community-acquired bacterial pneumonia. The 2010 Assessing Worldwide Antimicrobial Resistance Evaluation (AWARE) Surveillance Program in the United States collected a total of 8434 bacterial isolates from 65 US medical centers across 9 US regions. The isolates were cultured and tested for susceptibility to ceftaroline and comparator agents by reference minimum inhibitory concentration (MIC) methods. An analysis by US Census Bureau region demonstrated that Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), and coagulase-negative staphylococci (CoNS), including methicillin-resistant CoNS, were particularly susceptible to ceftaroline (MIC(90), 1 and 0.5?μg/mL respectively). The MRSA rate was 50.0% overall, which varied from a low of 44.6% in the South Atlantic region to a high of 53.1% in the Mountain region. Susceptibility among MRSA for ceftaroline ranged from 96.7% in the West South Central region to 100% in the West North Central region. All MRSA isolates were inhibited at a ceftaroline MIC of ≤2?μg/mL, and 98.4% were inhibited at a ceftaroline MIC of ≤1?μg/mL. In general, regional differences in activity among staphylococci, streptococci, Haemophilus spp., and Moraxella catarrhalis were minimal due to the high potency of ceftaroline. Greater differences in activity were observed among the Enterobacteriaceae due to the greater diversity of organism types and resistance mechanisms, including those producing extended-spectrum β-lactamase enzymes. 相似文献
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The concept of mimicking structural colour in nature as an alternative to traditional textile coloration techniques would reduce dependency on dyes, pigments and vast quantities of water in the textile supply chain. Structural colours originate from the physical interaction of light with nanoscale structures. This is exhibited in the bodies and wings of certain species of butterfly, beetles and plants. The angular optical effects of the Chrysina gloriosa beetle result from the periodicity due to the cholesteric liquid crystal (CLC) structure adopted by the cells in their exoskeleton. The optical properties of CLCs makes promising applications for optical sensors and anti-counterfeit materials. Application using inkjet printing technology enables designs to be tuned to meet product requirements, and with a hydrophobic treatment challenges associated with a rough surface such as textiles are overcome. Here we report inkjet printing CLC solutions onto hydrophobic pre-treated textiles. CIE L*a*b* values demonstrate the resultant colourful films display a greater degree of colour compared to those on untreated textiles.The concept of mimicking structural colour in nature as an alternative to traditional textile coloration techniques would reduce dependency on dyes, pigments and vast quantities of water in the textile supply chain. 相似文献
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Summary
The aim of this birth cohort study was to determine whether early life factors (birth weight, breastfeeding, and maternal smoking) were associated with bone mass and fractures in 16-year-old adolescents. The results suggest that breastfeeding is associated with higher bone mass and lower fracture risk at age 16 but not in utero smoking or birth weight.Introduction
There are limited data on early life influences on bone mass in adolescence but we have previously reported in utero smoking, breastfeeding, and birth weight were associated with bone mass at age 8.Methods
Birth weight, breastfeeding intention and habit, and maternal smoking during pregnancy were assessed at phase one in 1988–1999 and by recall during phase two in 1996–1997. Bone mineral density (BMD) was measured by dual-energy X-ray densitometry. Fractures were assessed by questionnaire. Subjects included 415 male and female adolescents from Southern Tasmania representing 29 % of those who originally took part in a birth cohort study in 1988 and 1989.Results
Breastfeeding (assessed in a number of ways) was associated with a 2–3 % increase in BMD at all sites apart from the radius and around a one third reduction in fracture risk which persisted after adjustment for confounders. In univariate analysis, birth weight was associated with BMD at the hip, radius, and total body but this did not persist in multivariate analysis and there was no association with fracture. Smoking in utero had no association with BMD at any site or fracture.Conclusions
Breastfeeding is associated with a beneficial increase in bone mass at age 16 and a reduction in fracture risk during adolescence. The association previously observed at 8 years of age is no longer present for birth weight or smoking in utero. 相似文献1000.
A. Y. Bijlsma M. C. G. Meskers M. Molendijk R. G. J. Westendorp S. Sipilä L. Stenroth E. Sillanpää J. S. McPhee D. A. Jones M. Narici H. Gapeyeva M. Pääsuke E. Seppet T. Voit Y. Barnouin J. Y. Hogrel G. Butler-Browne A. B. Maier 《Osteoporosis international》2013,24(10):2681-2691