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941.
通过重叠PCR扩增得到烟草丛顶病毒(Tobacco bushy top virus,TBTV)中国分离物RdRp的编码序列,构建以pMALC2X为基础载体的原核表达载体pMAL-TB-RdRp。0.5 mM IPTG诱导可特异性表达分子量约为120 kDa的MBP-RdRp融合蛋白。温度梯度实验显示,18℃下诱导表达的MBP-RdRp融合蛋白的可溶性比例较高,约17%;经亲和层析纯化的MBPRdRp可特异性识别TBTV正链和负链的3'末端序列,催化体外复制;对正负链的3'末端的体外复制效率存在差别,识别负链3'末端的体外复制效率明显高于正链3'末端。本研究创建的TBTV RdRp介导的体外复制体系为进一步研究TBTV基因组复制调控奠定了基础。 相似文献
942.
Letícia Aparecida de Moraes Julio Massaharu Marubayashi Valdir Atsushi Yuki Murad Ghanim Vinicius Henrique Bello Bruno Rossitto De Marchi Leonardo da Fonseca Barbosa Laura M. Boykin Renate Krause-Sakate Marcelo Agenor Pavan 《Phytoparasitica》2017,45(4):517-525
In Brazil, the first major invasion event of Bemisia tabaci was that of Middle East–Asia Minor 1 (MEAM1) species, formerly termed as B biotype, which commenced in the 1990s mainly by ornamental plants in São Paulo State. More than two decades after this invasion, the presence of the Mediterranean (MED) species of B. tabaci, formerly Q biotype, was reported in Rio Grande do Sul, the southernmost State of Brazil, and now in São Paulo and Paraná States, in southeastern Brazil. Specimens of whiteflies collected from commercial begonia, hydrangea, petunia and poinsettia greenhouses in São Paulo, and also from begonias and poinsettias collected in flower shops in Paraná, were all identified as belonging to MED species. Furthermore, the secondary endosymbionts Arsenophonus, Hamiltonella and Rickettsia of MED from São Paulo and Paraná were detected by PCR and their presence confirmed by sequencing and FISH analysis, and those results differed from MED detected in Rio Grande do Sul that harbored only Hamiltonella and Cardinium. Our results suggest a new MED invasion into Brazil and is associated with ornamental plants. The two MED populations are genetically different and suggest that they are separate invasions. 相似文献
943.
K. De Jonghe I. De Roo M. Maes 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(4):749-759
Over the years, real-time PCR outflanked endpoint PCR in phytopathogen diagnostics, mainly because of the increase in sensitivity and timesaving aspects of the technique. However, a time consuming 16S rRNA-based nested PCR method is still the gold standard for phytoplasma diagnosis. This is also the case for phytoplasma detection in Malus, Pyrus and Prunus, the three main host plants of apple proliferation (AP), pear decline (PD) and European stone fruit yellows (ESFY) phytoplasma, respectively. The last decade, loop-mediated isothermal amplification (LAMP) (Notomi et al. 2000) is gaining a lot in significance and is also for phytoplasmas expected to become a widely used reliable diagnostic tool. High specificity and sensitivity which also requires a less stringent need for DNA purification, and the short analysis time and the limited equipment requirements makes the LAMP method a fast and affordable alternative with great point-of-care diagnostic potential. In this paper, we present a LAMP primer set for the ribosomal group 16SrX, containing the important fruit tree phytoplasmas AP, PD and ESFY. The primers were developed and validated for fast and sensitive detection and general use for diagnosis. We foresee that the LAMP technique will also have its application in on-site diagnosis of the fruit tree phytoplasmas during inspections and surveys. 相似文献
944.
Evaluation of a decision support strategy for the control of powdery mildew,Erysiphe necator (Schw.) Burr., in grapevine in the central region of Chile
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945.
Moerkens Rob Berckmoes Els Van Damme Veerle Wittemans Lieve Tirry Luc Casteels Hans De Clercq Patrick De Vis Raf 《植物病害和植物保护杂志》2017,124(3):295-303
Journal of Plant Diseases and Protection - Macrolophus pygmaeus Rambur (Hemiptera: Miridae) is a key biological control agent in greenhouse tomato crops. In the present study, we describe the... 相似文献
946.
947.
Treatment of oral squamous cell carcinoma in a horse by surgical debulking followed by metronomic chemotherapy
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R. Tornago S. Sabattini A. De Simoi G. Bettini T. Furlanello V. Baldassarre M. Cornali M. Mazzucato S. Carlin F. Gentilini 《Equine Veterinary Education》2017,29(4):208-212
A 19‐year‐old Quarter Horse gelding presented with a 6‐week history of hypersalivation, halitosis and dysmasesis. Oral examination revealed retention of food and saliva and the presence of a raised, nodular, 6 × 7 cm, ulcerated mass on the dorsal surface of the tongue base. The mass was confirmed histologically as squamous cell carcinoma. Complete resection of the mass was not possible and surgical laser debulking was followed 15 days later by chemotherapy with a combination of meloxicam and cyclophosphamide in metronomic regimen. After one week, there was a significant improvement in clinical signs and food consumption returned to normal. Therapy was well tolerated with no alteration in haematological or urinalysis parameters. After 5 months of excellent life quality, the horse showed progressive difficulties in mastication and swallowing. Endoscopic examination showed extension of the tumour to all the aboral aspect of the tongue and, with the owner's consent, the patient was subjected to euthanasia. This is believed to be the first report on the combined use of meloxicam and cyclophosphamide in a metronomic fashion for management of an oral squamous cell carcinoma in a horse. Since metronomic therapy is less expensive than conventional chemotherapy, easily administrable and well tolerated, it should be considered as a possible treatment option for nonresectable equine malignant tumours. 相似文献
948.
Alternative method to facilitate resolution of paraphimosis after penile trauma in the horse
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Inflammation associated with traumatic injury to the penis is characterised by pain, heat and oedema. Ensuing penile swelling interferes with retraction of the penis into the prepuce, resulting in paraphimosis. This report describes the use of a 5 l capacity pressure infusion bag to reduce penile oedema in three horses. This technique provided complete resolution of oedema and associated paraphimosis in approximately 1 h. The use of the bag, along with an abdominoinguinal bandage, a plastic funnel suspensory device, or a penile repulsion device (Probang) to avoid recurrence, offers a novel treatment that may be performed with the horse sedated. 相似文献
949.
A. De Meyer S. Vandenabeele C. Ververs A. Martens K. Roels V. De Lange M. Hoogewijs C. De Schauwer J. Govaere 《Equine Veterinary Education》2017,29(1):7-9
An 11‐year‐old gelding presented with a large mass located in the dermis of his preputium that surrounded the penis completely. This mass was first noted years ago but did not increase in size. Histological examination diagnosed a fibroma. No treatment was initiated since no signs of discomfort were noticed and the gelding was performing at a high level in competitive showjumping. Next to skin tumours, tumours of the penis and preputium are most common. Most frequently, squamous cell carcinomas and sarcomas are diagnosed. Although fibromas can develop anywhere in connective tissue, a preputial location of a fibroma in a gelding is rare. Differential diagnosis and possible treatment options are discussed. 相似文献
950.
Rifampicin treatment of canine pyoderma due to multidrug‐resistant meticillin‐resistant staphylococci: a retrospective study of 32 cases
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