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81.
目的了解温州地区居民对甲型H1N1流感(以下简称甲流)的认知情况及其疫苗的不良反应,分析相关调查数据为医务人员加强疾病防控提供依据。方法采用自行设计问卷,随机抽取2010年3月-4月温州地区居民888人为调查对象,对其进行问卷调查。结果温州地区人群对甲流及其疫苗的认知程度平均得分为15.69分,处于中低水平,各年龄段、各职业人群在认知度上差异存在统计学意义(P<0.05),走访的113名70岁以上的老人在甲型H1N1信息上欠缺认识。调查对象中50.5%人群对甲流疫苗的安全性持质疑观望态度。调查对象中共115人已接种疫苗,13人出现不良反应,占11.3%。结论甲流疫苗具有较高的安全性,但温州地区人群对甲型H1N1流感相关知识了解欠缺,而且群众的信任度不高,因此仍应加大宣传力度,尤其加强对老年人的预防宣教。JP  相似文献   
82.
流感疫苗血凝素含量检测方法为单向免疫扩散试验,其抗血清通常由WHO参比实验室提供,通过纯化病毒、蛋白酶切获得血凝素主要抗原片段,然后再免疫动物获得抗血清。该方法制备时间较长,是制约流感疫苗研发及检测的主要因素。以RT-PCR方法获取甲型H1N1流感病毒血凝素中主要抗原片段基因,构建重组质粒并在大肠杆菌中表达,表达产物经纯化、复性后,以蛋白电泳及免疫印迹方法进行了鉴定。以纯化蛋白免疫家兔,制备了相应的抗体,初步证明可用于常规的单向免疫扩散试验。以该法可以快速获得抗血清,尤其是在大流行流感疫苗的研发中,加快疫苗研发进程。  相似文献   
83.
The aim of the work is the comparison of the epidemiology of influenza and acute respiratory virus infections (ARVI) in the Republic of Kazakhstan with the corresponding influenza epidemic in Russia induced by influenza pandemic virus A/California/07/2009 in 2009.Data on influenza and ARVI from the Republic of Kazakhstan and Federal Center of influenza was collected and investigated over the course of several weeks from hospitalized patients with the same diagnosis among all population and in age groups on ...  相似文献   
84.
Although the important role of the non-structural (NS1 and NEP) gene of influenza A in virulence of the virus is well established, our knowledge about the extent of variation in the NS gene pool of influenza A viruses in their natural reservoirs in Kazakhstan is incomplete. 17 influenza A viruses of different subtypes were studied in this paper. Seven types of haemagglutinin and five different neuraminidase subtypes in eight combinations were found among the isolated viruses. A comparison of nucleotide sequ...  相似文献   
85.
为体外验证流感病毒PB1-F2与热休克蛋白Hsp40相互作用,通过两个方向的GST pull-down试验验证PB1-F2与Hsp40的相互作用。构建GST-多肽融合蛋白原核表达载体pGEX-6P-1-PB1-F2和pGEX-6P-1-Hsp40,并在大肠杆菌(E.co-li)BL21中诱导表达;构建真核表达载体pLEGFP-Hsp40及pCAGGS-PB1-F2,并分别转染293T细胞使其表达Hsp40及PB1-F2融合蛋白,然后进行GST pull-down试验验证二者的相互作用。成功地构建了两种蛋白的各种表达载体,经表达、纯化获得了可溶性的GST-多肽融合蛋白,GST pull-down试验正反两方向都证实了PB1-F2与Hsp40的相互作用,初步证实了流感病毒PB1-F2在体外能与Hsp40发生相互作用。  相似文献   
86.
【目的】为了提高禽源大肠杆菌中耶尔森氏菌强毒力岛(HPI)的检测效率, 了解高分子量铁调节蛋白2基因(irp2)和整合酶基因(int)在不同株禽源HPI+大肠杆菌间的同源性, 进一步揭示禽源大肠杆菌HPI的转移规律。【方法】利用L16(44)正交试验设计, 建立针对HPI核心基因irp2和fyuA的双重PCR, 运用双重PCR方法检测禽源大肠杆菌临床分离株, 并对检出的7株HPI阳性(HPI+)大肠杆菌进行irp2和int基因测序及同源性分析, 同时结合这7株大肠杆菌的ERIC-PCR分析结果, 对比分析int基因的分布特点。【结果】结果显示, 新建立的双重PCR能特异性扩增出HPI核心基因; ERIC-PCR分析显示, HPI+大肠杆菌间差异均大于5%; HPI+大肠杆菌irp2基因高度保守(同源性大于99%), 而int基因虽然都位于asn-tRNA位点, 但基因序列在部分菌株间存在较大差异。【结论】建立了一种可以用于HPI的流行病学调查和实验室诊断的双重PCR方法, 并推测区域外同源重组可能是HPI基因在大肠杆菌间水平转移的主要方式。  相似文献   
87.
88.
The development of vaccination methods that can overcome the emergence of new types of influenza strains caused by escape mutations is desirable to avoid future pandemics. Here, a novel type of immunogen was designed that targeted the conformation of a highly conserved region of influenza A virus hemagglutinin (HA) composed of two separate sequences that associate to form an anti-parallel β-sheet structure. Our previous study identified this β-sheet region as the structural core in the epitope of a characteristic antibody (B-1) that strongly neutralizes a wide variety of strains within the H3N2 serotype, and therefore this β-sheet region was considered a good target to induce broadly reactive immunity against the influenza A virus. To design the immunogen, residues derived from the B-1 epitope were introduced directly onto a part of enhanced green fluorescent protein (EGFP), whose surface is mostly composed of β-sheets. Through site-directed mutagenesis, several modified EGFPs with an epitope-mimicking structure embedded in their surface were prepared. Two EGFP variants, differing from wild-type (parental) EGFP by only five and nine residues, induced mice to produce antibodies that specifically bind to H3-type HA and neutralize H3N2 virus. Moreover, three of five mice immunized with each of these EGFP variants followed by a booster with equivalent mCherry variants acquired anti-viral immunity against challenge with H3N2 virus at a lethal dosage. In contrast to conventional methods, such as split HA vaccine, preparation of this type of immunogen requires less time and is therefore expected to be quickly responsive to newly emerged influenza viral strains.  相似文献   
89.
Influenza is a severe disease in humans and animals with few effective therapies available. All strains of influenza virus are prone to developing drug resistance due to the high mutation rate in the viral genome. A therapeutic agent that targets a highly conserved region of the virus could bypass resistance and also be effective against multiple strains of influenza. Influenza uses many individually weak ligand binding interactions for a high avidity multivalent attachment to sialic acid-bearing cells. Polymerized sialic acid analogs can form multivalent interactions with influenza but are not ideal therapeutics due to solubility and toxicity issues. We used liposomes as a novel means for delivery of the glycan sialylneolacto-N-tetraose c (LSTc). LSTc-bearing decoy liposomes form multivalent, polymer-like interactions with influenza virus. Decoy liposomes competitively bind influenza virus in hemagglutination inhibition assays and inhibit infection of target cells in a dose-dependent manner. Inhibition is specific for influenza virus, as inhibition of Sendai virus and respiratory syncytial virus is not observed. In contrast, monovalent LSTc does not bind influenza virus or inhibit infectivity. LSTc decoy liposomes prevent the spread of influenza virus during multiple rounds of replication in vitro and extend survival of mice challenged with a lethal dose of virus. LSTc decoy liposomes co-localize with fluorescently tagged influenza virus, whereas control liposomes do not. Considering the conservation of the hemagglutinin binding pocket and the ability of decoy liposomes to form high avidity interactions with influenza hemagglutinin, our decoy liposomes have potential as a new therapeutic agent against emerging influenza strains.  相似文献   
90.
Rhodoxanthin is one of few retro-carotenoids in nature. These chromophores are defined by a pattern of single and double bond alternation that is reversed relative to most carotenoids. Rhodoxanthin is found in the plumage of several families of birds, including fruit doves (Ptilinopus, Columbidae) and the red cotingas (Phoenicircus, Cotingidae). The coloration associated with the rhodoxanthin-containing plumage of these fruit dove and cotinga species ranges from brilliant red to magenta or purple. In the present study, rhodoxanthin is characterized in situ by UV–Vis reflectance and resonance Raman spectroscopy to gain insights into the mechanisms of color-tuning. The spectra are compared with those of the isolated pigment in solution and in thin solid films. Key vibrational signatures are identified for three isomers of rhodoxanthin, primarily in the fingerprint region. Electronic structure (DFT) calculations are employed to describe the normal modes of vibration, and determine characteristic modes of retro-carotenoids. These results are discussed in the context of various mechanisms that change the electronic absorption, including structural distortion of the chromophore or enhanced delocalization of π-electrons in the ground-state. From the spectroscopic evidence, we suggest that the shift in absorption is likely a consequence of perturbations that primarily affect the excited state of the chromophore.  相似文献   
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