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71.
Histiostoma papillata sp. n. (Acari: Histiostomatidae) is described from Victoria, Australia. It was found in the fins and gills of juvenile Murray cod, Maccullochella peelii peelii (Mitchell), where it appeared to inflict injuries thought to be responsible for the mortality of fish in a diet trial.  相似文献   
72.
Aedes aegypti (L.) mosquitoes showed a significant reduction in susceptibility to infection with Ross River virus and Murray Valley encephalitis virus when they were fed on a blood-virus mixture containing rabbit antibodies to mosquito midgut components. Presence of the antibodies did not demonstrably affect virus titres in infected mosquitoes, nor the transmission of virus from infected mosquitoes to vertebrates.  相似文献   
73.
Six new natural compounds were isolated from two Far Eastern starfish species, Henricia aspera and H. tumida, collected in the Sea of Okhotsk. Two new glycosylated steroid polyols were obtained from H. aspera: asperoside A and asperoside B, which were shown to be (20R,24R, 25S)-3-O-(2,3-di-O-methyl-β -D-xylopyranosyl)-24-methyl-5α-cholest-4-ene-3β, 6β,8,15α,16β,26-hexaol and (20R, 24R,25S,22E)-3-O-(2,4-di-O-methyl-β-D-xylopyranosyl)-24-methyl-5α-cholest-22-ene-3β,4β,6β,8,15α,26-hexaol, respectively. Two other glycosylated polyols, tumidoside A, with the structure elucidated as (20R, 22E)-3-O-(2,4-di-O-methyl-β -D-xylopyranosyl)-26,27-dinor-24-methyl-5α-cholest-22-ene-3β,4β,6β,8,15α,25-hexaol, and tumidoside B, whose structure was elucidated as (20R,24S)-3-O-(2,3-di-O-methyl-β-D-xylopyranosyl)-5α-cholestan-3β,4β,6β,8,15α,24-hexaol, were isolated from the two starfish species. (20R, 24S)-5α-Cholestan-3β,6β,15α,24-tetraol and (20R, 24S)-5α-cholestan-3β,6β,8,15α,24-pentaol were identified only in H. tumida. The known monoglycosides henricioside H1 and laeviuscolosides H and G were also identified in both species.  相似文献   
74.
Murray Valley encephalitis virus is a member of the flavivirus group, a large family of single‐stranded RNA viruses, which cause serious disease in all regions of the world. Unfortunately, no suitable antivirals are available, and there are commercial vaccines for only three flaviviruses. The solid‐phase synthesis of a library of 400 C‐terminal arginine peptide aldehydes and their screening against Murray Valley encephalitis virus protease are demonstrated. The library was utilised to elucidate several tripeptide sequences that can be used as inhibitors in further SAR studies. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
75.
76.
蜜蜂残翅病毒(Deformed wing virus,DWV)广泛存在于我国规模化养殖的蜂群中,具有明显的季节流行特征.近年来,DWV不断向野生授粉昆虫及其它昆虫传播,包括蜜蜂新的寄生性病害蜂箱奇露尾甲Aethina tumida.前期本实验室已鉴定来源于中华蜜蜂Apis cerana与意大利蜜蜂Apis mellifera的蜂箱奇露尾甲均感染了蜜蜂病毒,但未调查来源于同一群的蜜蜂与蜂箱奇露尾甲是否感染了同一病毒,且在进化上有无差异.本研究调查了来源于同一群的中蜂及蜂箱奇露尾甲感染病毒情况,发现只感染了蜜蜂残翅病毒A型(DWV-A),未发现其它病毒.对DWV-A的3个片段进化分析表明,虽然DWV-A同时感染了中华蜜蜂和蜂箱奇露尾甲,但是VP3基因在不同的寄主中呈现明显不同的亲缘关系.这一结果为蜜蜂残翅病毒在蜜蜂及寄生病害中的进化提供了数据,为进一步研究病毒在不同寄主间的传播与进化奠定了基础.  相似文献   
77.
Culex annulirostris Skuse, colonized from Brisbane, Queensland, and Mildura, Victoria, Australia, were effective vectors of Murray Valley encephalitis virus at 20, 27 and 32-35 degrees C with full extrinsic incubation periods of 15, 10 and 4 days respectively. At 20 degrees C, 7-11 days post-infection, transmission by the Mildura colony (0-20%) was less efficient than the Brisbane colony (30-70%) but both were capable of 75-100% transmission after longer extrinsic incubation periods. Discriminant analysis of body and salivary gland titres showed that these were not satisfactory indicators of transmission. Wild-caught Aedes sagax (Skuse) and Cx annulirostris from the Murray Valley showed equal competence, but Aedes alboannulatus (Macquart) was a poor vector. The results provide data on rural amplification of Murray Valley encephalitis virus during spring and suggest that further work on the potential of Ae. sagax as a natural vector is warranted.  相似文献   
78.
蜂巢小甲虫Aethina tumida是一种新入侵为害蜜蜂蜂巢的危险性害虫,筛选出具有较高毒力水平的化学药剂防治该虫迫在眉睫。本文采用浸渍法测定了10种杀虫剂对蜂巢小甲虫幼虫的毒力。试验结果表明,10 mg/L高效氯氰菊酯、啶虫脒和功夫菊酯在24 h内对蜂巢小甲虫幼虫的致死率达到36.67%、33.33%和29.39%,而10 mg/L高效氯氰菊酯和功夫菊酯在48 h对蜂巢小甲虫幼虫的致死率均达到100%。啶虫脒、高效氯氰菊酯和功夫菊酯在24 h的LC_(50)分别为10.47 mg/L、16.94 mg/L和19.1 mg/L。其它受试的杀虫剂如多杀菌素、氟虫腈、氟啶脲、虫酰肼、敌百虫、阿维菌素和甲维盐的触杀致死率相对较低。筛选结果显示,啶虫脒、高效氯氰菊酯和功夫菊酯可作为目前防治蜂巢小甲虫的的重要参考防治药剂。  相似文献   
79.
蜂巢奇露尾甲Aethina tumida Murray是危害蜜蜂种群的入侵害虫,其入侵地已遍布世界各地,对蜜蜂养殖业造成巨大冲击,该虫已在我国广东、广西和海南等省分布并造成危害.本文综述蜂巢奇露尾甲的分类学地位、生物学习性、分布地与扩散路径、主要危害及防治措施等方面的研究进展,并总结和展望了该入侵种在我国的危害情况以及...  相似文献   
80.
Abstract   Our paper presents an assessment of research and operational development in relation to medically important mosquito-borne disease, mainly the arboviruses Ross River, Barmah Forest, Murray Valley encephalitis, Japanese encephalitis, Kunjin and dengue, but also with respect to malaria. Since 1972, there have been considerable gains in research output, organisational structure, communication, surveillance including quarantine inspection and operational control. This has been due to the 1974 epidemic of Murray Valley encephalitis virus extending into temperate Australia, increasing occurrence of Ross River and the dengue viruses, the discovery of Barmah Forest virus as a disease entity in 1988, and the introduction of Japanese encephalitis in 1995. Because many of the outputs involve methodologies of global import, this has resulted in an unprecedented upsurge in publications of international standard.  相似文献   
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