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排序方式: 共有1117条查询结果,搜索用时 15 毫秒
31.
32.
Respiratory Viruses Associated Hospitalization among Children Aged <5 Years in Bangladesh: 2010-2014
Nusrat Homaira Stephen P. Luby Kamal Hossain Kariul Islam Makhdum Ahmed Mustafizur Rahman Ziaur Rahman Repon C. Paul Mejbah Uddin Bhuiyan W. Abdullah Brooks Badrul Munir Sohel Kajal Chandra Banik Marc-Alain Widdowson Melisa Willby Mahmudur Rahman Joseph Bresee Katharine-Sturm Ramirez Eduardo Azziz-Baumgartner 《PloS one》2016,11(2)
Background
We combined hospital-based surveillance and health utilization survey data to estimate the incidence of respiratory viral infections associated hospitalization among children aged < 5 years in Bangladesh.Methods
Surveillance physicians collected respiratory specimens from children aged <5 years hospitalized with respiratory illness and residing in the primary hospital catchment areas. We tested respiratory specimens for respiratory syncytial virus, parainfluenza viruses, human metapneumovirus, influenza, adenovirus and rhinoviruses using rRT-PCR. During 2013, we conducted a health utilization survey in the primary catchment areas of the hospitals to determine the proportion of all hospitalizations for respiratory illness among children aged <5 years at the surveillance hospitals during the preceding 12 months. We estimated the respiratory virus-specific incidence of hospitalization by dividing the estimated number of hospitalized children with a laboratory confirmed infection with a respiratory virus by the population aged <5 years of the catchment areas and adjusted for the proportion of children who were hospitalized at the surveillance hospitals.Results
We estimated that the annual incidence per 1000 children (95% CI) of all cause associated respiratory hospitalization was 11.5 (10–12). The incidences per 1000 children (95% CI) per year for respiratory syncytial virus, parainfluenza, adenovirus, human metapneumovirus and influenza infections were 3(2–3), 0.5(0.4–0.8), 0.4 (0.3–0.6), 0.4 (0.3–0.6), and 0.4 (0.3–0.6) respectively. The incidences per 1000 children (95%CI) of rhinovirus-associated infections among hospitalized children were 5 (3–7), 2 (1–3), 1 (0.6–2), and 3 (2–4) in 2010, 2011, 2012 and 2013, respectively.Conclusion
Our data suggest that respiratory viruses are associated with a substantial burden of hospitalization in children aged <5 years in Bangladesh. 相似文献33.
34.
Improved heterologous production of the nonribosomal peptide‐polyketide siderophore yersiniabactin through metabolic engineering and induction optimization
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Biosynthesis of complex natural products like polyketides and nonribosomal peptides using Escherichia coli as a heterologous host provides an opportunity to access these molecules. The value in doing so stems from the fact that many compounds hold some therapeutic or other beneficial property and their original production hosts are intractable for a variety of reasons. In this work, metabolic engineering and induction variable optimization were used to increase production of the polyketide‐nonribosomal peptide compound yersiniabactin, a siderophore that has been utilized to selectively remove metals from various solid and aqueous samples. Specifically, several precursor substrate support pathways were altered through gene expression and exogenous supplementation in order to boost production of the final compound. The gene expression induction process was also analyzed to identify the temperatures and inducer concentrations resulting in highest final production levels. When combined, yersiniabactin production was extended to ~175 mg L?1. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1412–1417, 2016 相似文献
35.
36.
Kamal Rashidi Asl Bahman Hosseini Ali Sharafi Javier Palazon 《Engineering in Life Science》2019,19(1):73-89
The use of nanotechnology and biotechnology to improve the production of plant bioactive compounds is growing. Hyoscyamus reticulatus L. is a major source of tropane alkaloids with a wide therapeutic use, including treatment of Parkinson's disease and to calm schizoid patients. In the present study, hairy roots were obtained from two‐week‐old cotyledon explants of H. reticulatus L. using the A7 strain of Agrobacterium rhizogenes. The effects of different concentrations of the signaling molecule nano‐zinc oxide (ZnO) (0, 50, 100 and 200 mg/L), with three exposure times (24, 48 and 72 h), on the growth rate, antioxidant enzyme activity, total phenol contents (TPC), tropane alkaloid contents and hyoscyamine‐6‐beta‐hydroxylase (h6h) gene expression levels were investigated. Growth curve analysis revealed a decrease in fresh and dry weight of ZnO‐treated hairy roots compared to the control. ANOVA results showed that the antioxidant activity of the enzymes catalase, guaiacol peroxidase and ascorbate peroxidase was significantly higher in the ZnO‐treated hairy roots than in the control, as was the TPC. The highest levels of hyoscyamine (37%) and scopolamine (37.63%) were obtained in hairy roots treated with 100 mg/L of ZnO after 48 and 72 h, respectively. Semi‐quantitative RT‐PCR analysis revealed the highest h6h gene expression was in hairy roots treated with 100 mg/L of ZnO after 24 h. It can be concluded that ZnO is as an effective elicitor of tropane alkaloids such as hyoscyamine and scopolamine due to its enhancing effect on expression levels of the biosynthetic h6h gene. 相似文献
37.
Safaa Abd El-Moneim Mohammed Sherif Abd El-Moneimb Marouf Ahmed M. Erfana Jakeen Kamal Abd El-Haleem El-Jakee Ashgan M. Hessain Turki M. Dawoud Saleh A. Kabli Ihab M. Moussa 《Saudi Journal of Biological Sciences》2019,26(5):1084-1088
Calf diarrhea is one of the major health challenges in cattle herds. The bacteriological examination of fecal samples collected from apparently healthy and diarrheic calves' revealed isolation of 26 E. coli isolates out of 56 calves with an incidence of 46.4%. Serogroups O1, O26, O44, O55, O115, O119, O125, O146, and O151 were identified from the collected fecal samples. Using PCR all isolates was positive for ompA gene species specific for E. coli. While stx1 and eaeA genes detected with incidence of 3.8 and 19.2% respectively from the isolates. The presence of stx2 gene was negative in the fecal isolates. Among colostrum samples 4 E. coli isolates were detected and serogrouped to O26, O55 and O119. They were negative for eaeA, stx1 and stx2 except strain number 4 (O55) was positive for stx1. E. coli strains were sensitive to norfloxacin (80.7%) and resistant to ampicillin and cefotaxime (100% each). Based on our findings, there was no association between occurrence of E. coli and age of calf (2–14 days), while bottle feeding calf colostrum may be a source of E. coli contamination. 相似文献
38.
Amina M. Ibrahim Amira Kamal Ahmed Fayez A. Bakry Ibrahim Rabei Fathy Abdel-Ghaffar 《Molluscan research.》2019,39(3):224-233
ABSTRACTBiomphalaria alexandrina snails have been used as bioindicators for freshwater qaulity and the effects of some herbicides such as butralin, glyphosate-isopropylammonium and pendimethalin). In the present study the effect of these three herbicides on snail biochemistry was examined. The results indicated that the herbicides increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the haemolymph of B. alexandrina snails and significantly decreased total protein and albumin content. Light microscopical examinations of haemocytes monolayers of B. alexandrina snails showed three different cell types (small cells, granulocytes and hyalinocytes). All three herbicides caused abnormalities in cell shapes. Flow cytometric analysis of haemocytes from B. alexandrina demonstrated that circulating haemocyte populations could be divided into two main subtypes differing in their granularity (granulocytes or hyalinocytes) and size (large and small cells). In addition, the flow cytometric analysis showed that the total number of dead haemocytes in the haemolymph was significantly increased in treated groups compared to the control group. Phagocytosis in groups treated with the herbicides was highly significantly increased compared to the control indicating a very strong response of the treated snails. The results of the alkaline comet assay of DNA damage demonstrated that these herbicides have a genotoxic effect. 相似文献
39.
Angela M. Mech Kathryn A. Thomas Travis D. Marsico Daniel A. Herms Craig R. Allen Matthew P. Ayres Kamal J. K. Gandhi Jessica Gurevitch Nathan P. Havill Ruth A. Hufbauer Andrew M. Liebhold Kenneth F. Raffa Ashley N. Schulz Daniel R. Uden Patrick C. Tobin 《Ecology and evolution》2019,9(21):12216-12230
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40.
Goldman AS Guisinger VH Aikins M Amarillo ML Belizario VY Garshong B Gyapong J Kabali C Kamal HA Kanjilal S Kyelem D Lizardo J Malecela M Mubyazi G Nitièma PA Ramzy RM Streit TG Wallace A Brady MA Rheingans R Ottesen EA Haddix AC 《PLoS neglected tropical diseases》2007,1(1):e67