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81.
The 2015 epidemic of Middle East respiratory syndrome (MERS) in the Republic of Korea has been the largest outbreak outside Middle East. This epidemic had caused 185 laboratory-confirmed cases and 36 deaths in the Republic of Korea until September 2, 2015, which attracted public’s attention. Based on the detailed data of patients released by World Health Organization (WHO) and actual propagation of the epidemic, we construct two dynamical models to simulate the propagation processes from May 20 to June 8 and from June 9 to July 10, 2015, respectively and find that the basic reproduction number R
0 reaches up to 4.422. The numerical analysis shows that the reasons of the outbreak spread quickly are lack of self-protection sense and targeted control measures. Through partial correction analysis, the parameters β
1 and γ have strong correlations with R
0, i.e., the infectivity and proportion of the asymptomatic infected cases have much influence on the spread of disease. By sensitivity analysis, strengthening self-protection ability of susceptible and quickly isolating or monitoring close contacts are effective measures to control the disease. 相似文献
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This article examines the location-allocation of emergency service facilities as a research subject. The research presents the setup of the single allocation set covering location-allocation models for emergency service facilities under strong time constraints, in view of the shortage of hub & spoke network bypass. The article also presents an extension to the single allocation set covering location-allocation model (SASCP) and the SASCP model with bypass constraints (γ-SASCP) for emergency service facilities under large-scale emergency requirements. For the two models, an improved genetic algorithm was designed and the two models were respectively solved, with the effectiveness of the algorithm verified by a specific example. The impacts of change of parameters such as time discount rate, maximum time constraints, and bypass ratio on the model's results are compared and analyzed, based on solved results by the specific example. 相似文献
84.
M W Wong C B Xia M L Chen C X Zhang P S Mao G Q Nei Y Hosaka 《Japanese journal of medical science & biology》1988,41(1):31-36
Molluscicidal activity of B-2 (sodium 2,5-dichloro-4-bromophenol; called as Phebrol and registered in WHO as OMS 3012) was evaluated in a laboratory and the field trials were performed in two different localities in Yueyang city, China, for control of Oncomelania hupensis. B-2 was effective against O. hupensis both in the laboratory and in the field. A dosage of 50 g/m2 in 10% granular form or 20 ml/m2 in 25% liquid form of B-2 would be recommendable as a standard mollusciciding dose for control of O. hupensis. 相似文献
85.
咖啡酸及其酯类衍生物如绿原酸、迷迭香酸和咖啡酸苯乙酯等具有天然抗氧化、抗肿瘤、抗病毒和抗炎等重要的药理活性,具有广阔的药用开发前景。从天然药物中提取或者化学合成咖啡酸及其酯类衍生物,存在含量低、提取效率不高、催化成本高昂以及环境污染等问题。随着咖啡酸及其酯类衍生物合成途径解析和合成生物学的快速发展,微生物异源合成咖啡酸及其酯类衍生物的研究已逐渐展开。对微生物异源合成咖啡酸及其酯类衍生物合成途径的最新进展以及代谢工程策略进行了综述,并讨论了目前存在的问题和未来的发展趋势。 相似文献
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89.
Munoz Frances M. Patel Priya A. Gao Xinghua Mei Yixiao Xia Jingsheng Gilels Sofia Hu Huijuan 《Purinergic signalling》2020,16(1):97-107
Purinergic Signalling - Astrocytes mediate a remarkable variety of cellular functions, including gliotransmitter release. Under pathological conditions, high concentrations of the purinergic... 相似文献
90.
Yizhi Jiang Dongping Huang Yuji Kondo Miao Jiang Zhenni Ma Lu Zhou Jian Su Xia Bai Changgeng Ruan Zhaoyue Wang Lijun Xia 《Journal of cellular and molecular medicine》2020,24(7):4356-4361
Hereditary thrombotic thrombocytopenic purpura (TTP) is an autosomal recessive thrombosis disorder, caused by loss-of-function mutations in ADAMTS13. Mutations in the CUB domains of ADAMTS13 are rare, and the exact mechanisms through which these mutations result in the development of TTP have not yet been fully elucidated. In this study, we identified two novel mutations in the CUB domains in a TTP family with an acceptor splice-site mutation (c.3569−1, G>A, intron 25) and a point missense mutation (c.3923, G>A, exon 28), resulting in a glycine to aspartic acid substitution (p.G1308D). In vitro splicing analysis revealed that the intronic mutation resulted in abnormal pre-mRNA splicing, and an in vitro expression assay revealed that the missense mutation significantly impaired ADAMTS13 secretion. Although both the patient and her brother displayed significantly reduced ADAMTS13 activity and increased levels of ultra-large VWF (ULVWF) multimers in plasma, only the female developed acute episodes of TTP. Our findings indicate the importance of the CUB domains for the protein stability and extracellular secretion of ADAMTS13. 相似文献