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51.
Brucellosis is a zoonotic disease threatening the public health and hindering the trade of animals and their products, which has a negative impact on the economic development of a country. Vaccination is the most effective way to control brucellosis. The recombinant vector vaccines are promising candidates for immunization in humans and animals. In this study, the gene encoding OMP19 antigen was primarily amplified and cloned into an expression vector called pT1NX, and then transformed to L. casei cell via electroporation technique. The expression was confirmed using specific antibody against the recombinant protein via immunological screening tests such as western blot and immunofluorescence assay. Finally, recombinant L. casei was orally fed to mice and the results were further recorded, indicating that the mice group which received OMP19 through L. casei based vaccine represented a very good general and mucosal immune responses protective against challenges with virulent B. abortus 544 strain compared with negative control recipient groups. Therefore, the vaccine produced in this research plan can be a very good candidate for protection against brucellosis. 相似文献
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为挖掘“商薯19”的增产潜力,以商洛市农户常用的竖插法为对照,采用单株水平扦插法、双株水平扦插法栽培“商薯19”。结果发现双株水平扦插法总产量最高(3 037.81 kg/667 m2),与竖插法产量(1 838.7 kg/667 m2)差异显著(P<0.05)。进一步统计不同扦插方式的大、中薯数量、产量及大、中薯率发现,双株水平扦插法主要通过增加大薯产量和中薯数量来达到增产效果。双株水平扦插法能够同时适应生产淀粉和鲜食的需求,有必要进一步试验、示范和推广。 相似文献
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通过五元二次回归正交旋转组合设计试验,建立了博优湛19主要农艺措施与产量的数学模型,通过模拟寻优频率分布分析了栽培措施对产量的影响,并通过通径分析研究了产量构成因素对产量的影响,结果表明:博优湛19的主要增产途径是增加有效穗,其次是争大穗。配套的栽培技术模式是:5.4~5.7叶移栽,插植密度39.6~40.2万穴/hm2,施纯N170.7~175.8kg/hm2,P2O5125.4~130.2kg/hm2,K2O126.0~131.4kg/hm2,结合其它科学管理措施,可获得7875kg/hm2以上的产量。 相似文献
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IntroductionPark crimes may have increased during the COVID-19 pandemic as a result of lockdowns that limited the number of capable guardians in public spaces. Despite this, the impacts of the lockdowns on park crimes remain unknown. To help us understand the societal impacts of policies implemented during this period, we assessed how the onset of the COVID-19 restrictions impacted urban park crime levels in London, England.MethodsWe identified crimes that occurred in publicly accessible parks and gardens in the Greater London Authority (England, UK) between March 1, 2019 and February 28, 2021 by overlaying open-access crime data with greenspace data supplied by the Greater Information for Greater London service. Using interrupted time series analyses, we estimated seasonality-adjusted associations between the onset of COVID-19 restrictions and park crimes.ResultsOverall (1565.7, 95% confidence intervals [CI] 1021.9 to 2109.5) and antisocial behaviour crimes (1772.7, 95% CI 823.6–2721.7) increased in London parks during the first full month of COVID-19 restrictions (April 2020). There were no notable trends in park crimes in London prior to the onset of restrictions, but overall and antisocial behaviour crimes decreased after the onset of restrictions at a rate of 156.4 (95% CI −220.25 to −92.51) and 164.7 (95% CI −280.68 to −48.74) crimes/months, respectively.ConclusionsOverall park crimes increased during the first full month of the COVID-19 restrictions, largely driven by an increase in antisocial behaviours. Additional research is needed to identify the specific misdemeanours that accounted for this rise in antisocial behaviours and to investigate their downstream impacts (e.g. increases in policing costs or decreases in perceived park safety). 相似文献
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Urban forests provide multiple ecosystem services for city dwellers, amongst which improving public health via mitigating mental stresses and providing attractive spaces for diverse physical activities has attracted increasing attention from scholars and policy makers within the context of the ongoing COVID-19 pandemic as well as urgently-needed post-pandemic urban transformation towards healthy cities. This short communication summarizes existing empirical evidence pertinent to the linkage between urban forests and public health maintenance and improvement, highlights three underlying mechanisms, i.e., physiological, psychological, and immunological pathways, and outlines practical implications for the establishment and management of urban forests as a strategy for planning healthy cities. 相似文献
57.
Anne Koh Tessa Morgan Janine Wiles Lisa Williams Jing Xu Merryn Gott 《Asia Pacific viewpoint》2023,64(1):60-71
Later-life migrants, as older people living away from their home nations, occupy multiply-precarious positions in relation to national COVID-19 pandemic responses. Concern has particularly centred on this group's increased risk of social and linguistic exclusion. We explore the perspectives of later-life older Chinese and Koreans living in New Zealand during the nation's COVID-19 lockdown of 2020. This paper presents a sub-analysis of culturally-matched interviews conducted with 3 Korean and 5 Chinese later-life migrants. These participants are a sub-sample of a larger qualitative interview study comprising 44 interviews. A social capital approach has been used to aid conceptualisation of participants' experiences and a reflexive thematic approach guided analysis. Despite their underrepresentation in national response efforts, Chinese and Korean later-life migrants resourcefully participated in ethnically-specific pandemic initiatives. Three themes identified were: (1) taking it seriously (2) already digitally literate (3) challenges and difficulties. Older Asian migrants engaged in a range of creative strategies to stay connected during COVID-19 lockdowns which drew heavily on pre-existing social capital. Future pandemic responses should seek to improve connectedness between the national government COVID-19 response and older Korean and Chinese later-life migrants. 相似文献
58.
烟草赤星病对不同部位烟叶化学成分的影响 总被引:1,自引:0,他引:1
高家合 《山地农业生物学报》2005,24(4):311-314
在烤烟调制期分下二棚叶、腰叶、上二棚叶及顶叶4个部位,进行烟草赤星病Alternaria alternata(Fries)Kissler不同危害程度对烟叶化学成分的影响研究。结果表明,受赤星病的危害后,烤烟4个部位烟叶总糖、还原糖含量比同部位对照(0级病害)有减少趋势,总氮、蛋白质及烟碱比同部位对照增加。下二棚叶病害级别与总氮、蛋白质、烟碱含量呈极显著强正相关。腰叶病害级别与烟碱含量呈显著正相关,与总糖、还原糖含量呈显著负相关,与总氮、蛋白质、钾含量呈极显著强正相关,与氯含量呈极显著强负相关。上二棚叶病害级别与总糖含量呈显著负相关,与总氮、蛋白质含量呈极显著强正相关。顶叶病害级别与总糖、还原糖、氯含量呈显著负相关。 相似文献
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根据鉴定得到青稞类钙调素蛋白基因CML19的序列设计引物,以青稞叶片的cDNA为模板,扩增得到目的片段,对目的基因序列进行鉴定和分析,进一步构建该基因的原核表达载体pET28a-CML19,转入大肠杆菌BL21(DE3),利用IPTG诱导外源蛋白质表达并检测。结果表明,扩增得到CML19的CDS序列全长为447bp,编码的蛋白质含有148个氨基酸,分子质量为16.46ku,理论等电点(pI)为4.40,总平均亲水性(GRAVY)为-0.176,不稳定系数为49.59,存在典型的EF手结构域;系统进化分析表明,青稞CML19与山羊草具有较近的亲缘关系;原核表达蛋白结果显示,重组蛋白主要以包涵体形式存在于沉淀中。初步阐明青稞CML19基因的序列特征,为进一步制备抗体、探讨CML19基因的功能奠定基础。 相似文献
60.