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101.
The study on buffalo babesiosis indicated that its pathogen was different from other Babesia on many aspects such as morphology, transmission and pathogenicity. Therefore, it was named as a new species—Babesia orientalis. In order to prove the validity of this taxon, molecular taxonomic study on the pathogen was done in this experiment. The complete 18S rRNA gene sequence of B. orientalis was determined by PCR. It was sequenced and blasted. The results indicated that the classification of the parasite belonged to the genus Babesia. The 1700 bp complete sequence was compared with 15 other Babesia sp. available in GenBank. The data were analyzed and a phylogenetic tree was established. The results indicated that the hereditary distance of the parasite was close to that of Babesia sp. from South Africa and Babesia ovis, and the hereditary distance was far from Babesia bigemina and B. bovis. 相似文献
102.
采用蛋白酶 K 消化,酚、氯仿抽提的方法提取法氏囊匀浆和细胞培养液中的鸡传染性法氏囊病病毒( I B D V)基因组 R N A,用特异的寡核苷酸引物对其 V P2 高变区进行反转录套式 P C R 扩增。应用该方法从一个法氏囊匀浆中即可特异地检出 I B D V R N A,得到的扩增产物可用于分子流行病学的进一步分析,而从感染材料的处理到扩增结果的电泳检测,在两个工作日之内可轻松完成。本实验为法氏囊病病毒的诊断和分子流行病学的分析提供了一种快速、简便、可靠的手段。 相似文献
103.
向非鸣禽雀鹰(Accipiternisus)的耳蜗内注入CB—HRP溶液,结果发现在同侧的听神经内有许多的标记纤维;同侧的角状核及巨细胞核内有较密集的标记终末。表明由耳蜗神经元发出的纤维组成听神经后,分别投射到耳蜗核的两对亚核,即角状核和巨细胞核。尼氏染色法表明,角状核和巨细胞核有不同的核团形态和细胞组成。提示这两对耳蜗亚核可能具有不同的听觉和定向功能。 相似文献
104.
植物病原真菌尖孢镰刀菌检测与定量研究进展 总被引:1,自引:0,他引:1
尖孢镰刀菌(Fusarium oxysporum)是一种危害严重的土传病原真菌,被列为世界十大植物病原真菌之一.该菌能够侵染棉花(Gossypium hirsutum)、大豆(Glycine max)、西瓜(Citrullus lanatus)、香蕉(Musa nana)、番茄(Lycopersicon esculen... 相似文献
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Santiago ME Vasconcelos RO Fattori KR Munari DP Michelin Ade F Lima VM 《Veterinary parasitology》2007,150(4):283-290
Blood and bone marrow samples were taken from 112 Didelphis spp., collected between March 2005 and February 2006, from urban and peri-urban areas of Bauru, São Paulo State, Brazil, to evaluate the hypothesis that these animals might constitute a reservoir of Leishmania spp. Anti-Leishmania ssp. antibodies were screened in the serum samples using an enzyme-linked immuno-sorbent assay (ELISA) and the polymerase chain reaction (PCR). PCR was performed on fragments of DNA samples from Leishmania spp. using primers 13A and 13B, and showed a positive outcome in 91.6% of the 112 samples tested. Of the 107 samples analyzed by ELISA, 71% were positive. Evidence of epidemiological risk factors such as a circulating parasite and freely moving vectors suggests that Didelphis spp. may participate in the transmission cycle of Leishmania spp. in Bauru. 相似文献
107.
以平凉市退耕还草产业化技术开发为例,以产业化系统链中各子系统间的功能协调统一为依据,以退耕还草产业化机制为纽带,在研究建立平凉市退耕还草产业化技术经济效果包括4个一级指标(基础指标、配套指标、服务指标和效益指标)和17个二级指标体系的基础上,采用层次分析法(AHP法)、隶属度函数法和综合效益指数法作为退耕还草产业化技术经济效果的评价方法.经比较得出:平凉市退耕还草产业化技术开发综合指数达到0.595 1,属初步产业化阶段,相对发展指数达到27.268%,年均产业化进步速度达到6.817%. 相似文献
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《African Zoology》2013,48(3):181-185
Recent reports on finding Wolbachia-strain infections in field mosquito species in some West African countries and the potential for developing these as disease vector biocontrol tools have prompted a search for Wolbachia in mosquitoes within the study area. Using a completely randomised design, mosquito traps were set at different locations in a rural and an urbanised community. One hundred and eighty (180) mosquitoes were trapped and pooled on the basis of genus, sex and site of collection, because there have been no earlier reports of Wolbachia isolated from Nigeria. Twenty pools, made up of not more than ten mosquitoes per pool, were homogenised and analysed for Wolbachia-specific DNA. Mosquitoes were trapped within Ede (urbanised community) and Akoda (rural community). Genomic DNA was extracted from trapped mosquito samples and used as a template in a PCR reaction. The Wolbachia sp. specific 16S rRNA gene was amplified, sequence analysis of PCR products was performed and a chromatogram of the sequence was subjected to Basic Local Alignment Search Tool analysis to identify the Wolbachia sp. This sequence was subsequently submitted to GenBank with accession number MK127541. The first evidence of the presence of the endosymbiont, Wolbachia in field-caught mosquitoes is hereby documented. The homology of this strain of Wolbachia bears similarities to those reported recently from other parts of West Africa and forms a single clade with a Wolbachia sp. from Mali, with a strong bootstrap support of 99%. This finding of a Wolbachia strain in mosquitoes at Ede could form the basis for more searches for diverse strains of Wolbachia in Nigeria. 相似文献