黄芩灰霉病发生规律及药效试验

对黄芩灰霉病在承德地区的发病规律进行了系统的调查。结果表明:黄芩灰霉病有2种危害型,即普通型和茎基腐型,病害的发病高峰期为6月上、中旬,随着降雨量的增加,枯枝率增加,田间降雨量与枯枝率呈正相关。采用地上喷雾法进行初步药剂防治,70%灰霉速克WP 60g/667m2防治效果达到76.43%、50%灭霉灵WP 100 g/667m2的防效达76.21%。     

空肠弯曲菌毒力因子研究进展

空肠弯曲菌(Campylobacter jejuni)是世界范围内广泛流行的人畜共患病,在公共卫生学上具有重要意义。空肠弯曲菌可引发人和多种动物疾病,其抗原结构复杂,致病机理尚不清楚。作者通过对空肠弯曲菌可能的毒力因子及其在致病中的作用作一简要概述,为空肠弯曲菌的诊断防治提供依据。     

牛瘤胃酸中毒发病机制与防治的研究进展

随着牛集约化养殖的发展,高精饲料的使用越来越广泛,这在不断提高牛生产性能的同时也引起了一些营养代谢病,特别是瘤胃酸中毒的发生,给养殖业造成了巨大的经济损失。作者就牛瘤胃酸中毒的发病机制与防治进行了较为系统地论述,以期为临床生产中更有效地预防和控制该病的发生和流行提供一定的理论参考。     

Roles of reactive oxygen species in interactions between plants and pathogens

The production of reactive oxygen species (ROS) by the consumption of molecular oxygen during host–pathogen interactions is termed the oxidative burst. The most important ROS are singlet oxygen (¹O₂), the hydroxyperoxyl radical (HO₂·), the superoxide anion , hydrogen peroxide (H₂O₂), the hydroxyl radical (OH^-) and the closely related reactive nitrogen species, nitric oxide (NO). These ROS are highly reactive, and therefore toxic, and participate in several important processes related to defence and infection. Furthermore, ROS also play important roles in plant biology both as toxic by-products of aerobic metabolism and as key regulators of growth, development and defence pathways. In this review, we will assess the different roles of ROS in host–pathogen interactions with special emphasis on fungal and Oomycete pathogens.     

Vuculic acid对空心莲子草叶片光合作用的影响

Vulculic acid(2-乙酰基-3,4-二羟基-5-甲氧苯基-乙酸)是从空心莲子草(Alternanthera philoxeroides)潜在生防真菌莲子草假隔链格孢(Nimbya alternantherae)培养滤液中分离获得的致病毒素.研究表明,该毒素为非寄主专化毒素,能够引致空心莲子草叶片细胞膜透性升高,导致电解质渗漏,同时降低叶片细胞内过氧化物酶(POD)和过氧化氢酶(CAT)的活性,使细胞防御酶系统发生紊乱,还能够造成空心莲子草叶片细胞质壁分离、质膜消解,叶绿体片层紊乱、膜消解[1,2].     

Direct visualization of the novel pathogen,Spiroplasma eriocheiris,in the freshwater crayfish Procambarus clarkii (Girard) using fluorescence in situ hybridization

Spiroplasma eriocheiris is the first spiroplasma strain known to be pathogenic to freshwater crustaceans. It has caused considerable economic losses both in the freshwater crayfish Procambarus clarkii (Girard) and in some other crustaceans. The monitoring of the pathogen in crustacean populations and study of its behaviour in the laboratory require the development of reliable diagnostic tools. In this article, we improved microscopic identification of S. eriocheiris by combining in situ hybridization with specific fluorescently labelled oligonucleotide probes. The established fluorescence in situ hybridization (FISH) allowed simultaneous visualization, identification and localization of S. eriocheiris in the tissues of diseased crayfish P. clarkii and exhibited low background autofluorescence and ideal signal‐to‐noise ratio. With the advantages of better tissue penetration, potentially more specific and stable, we designed three species‐specific oligonucleotide probes utilizing the sequences of 16S‐23S rRNA intergenic spacer regions (ISRs) of S. eriocheiris. Positive hybridization signals were visualized in haemocytes and connective tissues of hepatopancreas, cardiac muscle and gill from diseased crayfish. This unique distribution pattern matched the pathological changes when diagnosed by H&E staining and indicated that S. eriocheiris probably spread throughout the tissues in P. clarkii by hemokinesis. This assay will facilitate our understanding of the pathogenesis of S. eriocheiris and enhance the early diagnosis of the novel pathogen.     

The β‐amylase genes: negative regulators of disease resistance for Verticillium dahliae

Little is known about the role of plant primary metabolism in defence against pathogens. The present study is the first investigation published that examines the role of β‐amylase (BAM) genes upon fungal, Verticillium dahliae, infection. The responses of Arabidopsis thaliana plants impaired in BAM1, BAM2, BAM3, BAM4 genes, along with double, triple and quadruple mutants of those genes, were used to explore the involvement of BAM in the host plant–V. dahliae interaction. Less severe symptoms were recorded in bam mutants compared to wild type. Real‐time quantitative PCR (qPCR) revealed that the decrease in symptom severity shown in bam plants was correlated with reductions in the growth of the pathogen in the plants. Confocal microscopy of the most and least susceptible bam mutants and the wildtype plants showed that there were no differences between them in the number of attached conidia and penetration sites on the roots. BAM1, BAM2 and BAM3 expression was altered upon V. dahliae infection in the aerial tissues of the wild type. Analysis by qPCR of the PR1 and PDF1.2 expression in the bam3, bam1234, bam14 and wildtype plants showed that PR1 was up‐regulated in the roots of bam plants upon V. dahliae infection.     

中西医结合脑心同治论治大面积脑梗死合并冠心病的体会

脑卒中是我国主要致残、致死性疾病,大面积脑梗死是其中预后较差的一类,且常合并冠心病。本文从中西医结合脑心同治理论阐述大面积脑梗死合并冠心病的治疗体会,主张急性期“闭证宜开”、“脱证宜固”以治其标,后期当滋养肝肾、化痰通络以治其本,并结合西医治疗,取得良好疗效,值得借鉴。