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81.
掌握百色市乙型肝炎疫苗纳入儿童免疫规划后的免疫效果,客观评价免疫规划工作现状。方法按现况研究原理,全市12个县(区),每个县(区)各抽取150名儿童,每个县在东、西、南、北、中五个方位随机抽取5个行政村,每个行政村抽取6个年龄组(1~6岁儿童),每个年龄组抽取5名常住儿童(当地居住三个月以上),收集血清样本进行乙肝病毒感染相关标志表面抗原及抗体检测。结果全市共调查1~6岁儿童1 809名儿童,乙肝表面抗原携带率为0.66%,低于2006年全国调查的1~4岁人群乙肝表面抗原携带率(0.96%),达到中国《2006—2010年全国乙型病毒性肝炎防治规划》提出的5岁以下儿童乙肝表面抗原携带率<1%的控制目标要求;1~6岁儿童乙肝表面抗体阳性率为77.77%,高于2006年全国调查的1~4岁人群乙肝抗体阳性率(71.24%)。结论百色市自2003年将乙肝疫苗纳入免疫规划管理后,乙肝免疫效果显著,乙肝病毒表面抗原阳性率大幅度下降,婴幼儿体内保护性抗体水平也高于全国水平。加强对孕产妇住院分娩率和婴幼儿乙肝疫苗接种工作,尤其是乙肝疫苗首针及时接种是今后乙肝预防控制的重点。 相似文献
82.
Franziska Enzmann Markus Stckl An‐Ping Zeng Dirk Holtmann 《Engineering in Life Science》2019,19(2):121-132
Facing energy problems, there is a strong demand for new technologies dealing with the replacement of fossil fuels. The emerging fields of biotechnology, photobiotechnology and electrobiotechnology, offer solutions for the production of fuels, energy, or chemicals using renewable energy sources (light or electrical current e.g. produced by wind or solar power) or organic (waste) substrates. From an engineering point of view both technologies have analogies and some similar challenges, since both light and electron transfer are primarily surface‐dependent. In contrast to that, bioproduction processes are typically volume dependent. To allow large scale and industrially relevant applications of photobiotechnology and electrobiotechnology, this opinion first gives an overview over the current scales reached in these areas. We then try to point out the challenges and possible methods for the scale up or numbering up of the reactors used. It is shown that the field of photobiotechnology is by now much more advanced than electrobiotechnology and has achieved industrial applications in some cases. We argue that transferring knowledge from photobiotechnology to electrobiotechnology can speed up the development of the emerging field of electrobiotechnology. We believe that a combination of scale up and numbering up, as it has been shown for several photobiotechnological reactors, may well lead to industrially relevant scales in electrobiotechnological processes allowing an industrial application of the technology in near future. 相似文献
83.
Yugang Zhang Huaiqing Cao Zhirong Liu 《Protein science : a publication of the Protein Society》2015,24(5):688-705
To assess the potential of intrinsically disordered proteins (IDPs) as drug design targets, we have analyzed the ligand-binding cavities of two datasets of IDPs (containing 37 and 16 entries, respectively) and compared their properties with those of conventional ordered (folded) proteins. IDPs were predicted to possess more binding cavity than ordered proteins at similar length, supporting the proposed advantage of IDPs economizing genome and protein resources. The cavity number has a wide distribution within each conformation ensemble for IDPs. The geometries of the cavities of IDPs differ from the cavities of ordered proteins, for example, the cavities of IDPs have larger surface areas and volumes, and are more likely to be composed of a single segment. The druggability of the cavities was examined, and the average druggable probability is estimated to be 9% for IDPs, which is almost twice that for ordered proteins (5%). Some IDPs with druggable cavities that are associated with diseases are listed. The optimism versus obstacles for drug design for IDPs is also briefly discussed. 相似文献
84.
Edwardsiella tarda and Streptococcus iniae are important fish pathogens. We have reported previously a live E. tarda vaccine based on the attenuated strain TX5RM and a S. iniae DNA vaccine based on the antigen Sia10. In this study, we examined the possibility of constructing a cross‐genus vaccine by taking advantage of the residual infectivity of TX5RM and using it as a carrier host for the natural delivery of a S. iniae DNA vaccine. For this purpose, the recombinant TX5RM, TX5RMS10, was created, which harbours and retains stably the DNA vaccine plasmid pCS10 that expresses Sia10. When flounder were vaccinated with TX5RMS10 via oral and immersion routes, TX5RMS10 was detected in multiple tissues within 12–14 days postvaccination (p.v.). At 7 and 14 days p.v., expression of the DNA vaccine was detected in spleen, kidney and liver. Following E. tarda and S. iniae challenge at one and 2 months p.v., the vaccinated fish exhibited relative per cent survival rates of 69–83%. Immunological analysis indicated that TX5RMS10‐vaccinated fish produced specific serum antibodies and exhibited enhanced expression of a wide range of immune genes. 相似文献
85.
Lactococcus lactis carrying a DNA vaccine coding for the ESAT‐6 antigen increases IL‐17 cytokine secretion and boosts the BCG vaccine immune response 下载免费PDF全文
86.
探讨枸杞多糖(Lycium barbarum polysaccharide,LBP)作为佐剂对H5亚型流感病毒全病毒灭活疫苗的体液免疫增强效果。将流感病毒A/Vietnam/1194/2004(H5N1)灭活疫苗与不同剂量的枸杞多糖混合后以腹腔注射的方式共同免疫小鼠,免疫后三周收集血清用于特异性抗体检测。实验中设立氢氧化铝佐剂组作对照共同评价LBP作为佐剂的免疫增强效果。结果显示,小鼠血清中针对H5灭活疫苗的特异性抗体水平在一定范围内随着LBP剂量的增加而提高。LBP在800μg剂量时血清特异性抗体水平较无佐剂组显著增强,并与氢氧化铝佐剂组大致相当。因而,LBP有可能成为一种有效的流感灭活疫苗免疫佐剂。 相似文献
87.
Ernest Giralt 《Journal of peptide science》2015,21(6):447-453
Peptides are destined to play a major role as therapeutic agents. My laboratory is contributing to speeding up this process. On the one hand, we devote efforts to studying the molecular details and dynamics of the events that occur during molecular recognition at protein surfaces. We succeeded to design and synthesize peptides able to modulate these recognition events either permanently or in response to light. On the other hand, we are discovering and designing peptides able to cross biological barriers. Our aim is to use these peptides as shuttles for targeting therapeutic agents to organs, tissues, or cells, with a special emphasis on drug delivery to the brain. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
88.
花颜色和花气味的量化研究方法 总被引:3,自引:0,他引:3
花颜色和花气味是花部构成的重要内容。在已开展的传粉生态学研究中对二者的报道主要是描述性的,而其量化研究可以为揭示传粉机制提供有力的实验证据。本文主要介绍了花颜色的测量和标定方法,包括比色卡、分光色差仪和便携式光谱仪等;花气味的采集方法,包括动态顶空套袋-吸附采集法、吸附-溶剂洗脱法和固相微萃取法等;花气味的检测和分析方法,包括气相色谱-质谱联用仪分析和电子鼻型超速气相色谱仪分析等;以及昆虫行为学实验方法,包括气相色谱-昆虫触角电位联用技术、Y型嗅觉仪和飞行箱实验等。科研人员可以根据实验材料的特点和实验目的选择适合的量化研究方法。 相似文献
89.
应用均匀设计、二次多项式逐步回归分析对烟管菌(Bjerkandera adusta)WZFF.W-Y11产漆酶液态发酵培养基进行优化。结果表明,培养基组成为麸皮水解液1%、淀粉24.0 g/L、葡萄糖24.0 g/L、豆饼粉4.8 g/L、NH4Cl 3.2g/L、KH2PO4 3.2 g/L、MgSO4·7H2O 0.2 g/L、CuSO4 ·5H2O 0.006 g/L,起始pH6.5,在28℃、150r/min、250mL的摇瓶培养条件下可以稳定地获得9672U/L的漆酶活力。 相似文献
90.
核酸序列中包含一定的蛋白质结构信息。根据通常情况下遗传密码表中密码子中间位的碱基配对时产生的氢键数目,尝试将20种氨基酸划分为两类,并用自编的计算机软件对蛋白质二级结构数据库中两类氨基酸的类聚现象进行了统计分析。结果表明,使用这种方法对氨基酸进行划分后,氨基酸残基具有较大概率与划入同一类的氨基酸残基相邻出现,并且这种聚集体对二级结构具有一定的偏好性。最后按照该方法设计了一段氨基酸序列并给出了预测服务器预测得到的结构。 相似文献