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81.
82.
Stephen B Hussey Rodney Clark Katharine F Lunn Cormac Breathnach Gisela Soboll J Millar Whalley D Paul Lunn 《Journal of veterinary diagnostic investigation》2006,18(4):335-342
Equine herpesvirus-1 (EHV-1) infection is common in young horses throughout the world, resulting in respiratory disease, epidemic abortion, sporadic myelitis, or latent infections. To improve on conventional diagnostic tests for EHV-1, a real-time polymerase chain reaction (PCR) technique was developed, using primers and probes specific for the EHV-1 gB gene. Amplification efficiencies of 100% +/- 5% were obtained for DNA isolated from a plasmid, infected peripheral blood mononuclear cells (PBMCs), and nasal secretions from infected ponies. The dynamic range of the assay was 8 log10 dilutions, and the lower limit of detection was 6 DNA copies. Fifteen ponies, seronegative for EHV-1, were experimentally infected with EHV-1, and nasal samples were used to quantify shedding of virus by both virus isolation and real-time PCR analysis. Virus isolation identified nasal shedding of EHV-1 in 12/15 ponies on a total of 25 days; real-time PCR detected viral shedding in 15/15 ponies on 75 days. Viremia was quantified using PBMC DNA, subsequent to challenge infection in 3 additional ponies. Viremia was identified in 1/3 ponies on a single day by virus isolation; real-time PCR detected viremia in 3/3 ponies on 17 days. When real-time PCR was used to analyze PBMC DNA from 11 latently infected ponies (documented by nested PCR), EHV-1 was not detected. We conclude that real-time PCR is a sensitive and quantitative test for EHV-1 nasal shedding and viremia and provides a valuable tool for EHV-1 surveillance, diagnosis of clinical disease, and investigation of vaccine efficacy. 相似文献
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85.
精子受精抗原-1(FA-1) mRNA在绵羊睾丸和附睾中的表达 总被引:1,自引:0,他引:1
本研究通过RT-PCR检测了该基因在绵羊睾丸和附睾中的表达情况。首先,提取绵羊睾丸组织、附睾头、体、尾部组织总RNA,以此为模板,反转录合成cDNA,自行设计引物,PCR扩增出462 bp的目的DNA。然后,将目的片断克隆入T载体,通过菌液PCR和重组质粒酶切,鉴定重组质粒中的目的DNA。再经序列分析鉴定目的片断。同时,以β-actin为内参照物,进行RT-PCR半定量分析,比较精子受精抗原(FA-1)在睾丸、附睾头、体、尾组织中的表达量。结果表明,FA-1在绵羊睾丸和附睾中均表达。 相似文献
86.
日光温室牡丹花石榴光合特性研究 总被引:1,自引:0,他引:1
以LI-6400光合作用测定系统对日光温室牡丹花石榴的光合特性进行测定。结果表明,在晴天条件下,牡丹花石榴光合速率日变化呈双峰曲线,最高峰在8时,次峰在15时,中午有明显的“午休”现象。光合作用的光补偿点和饱和点分别为32μmol/m2/s和1200μmol/m2/s,CO2补偿点和饱和点分别为16μmol/mol和850μmol/mol。 相似文献
87.
L.G. Lapchic A.J. Clark G.P. Lomonossoff M. Shanks 《European journal of plant pathology / European Foundation for Plant Pathology》1998,104(4):409-412
The relationship between red clover mottle virus (RCMV) isolated in the Ukraine (designated RCMV-Uk) and well-characterised strains from Sweden has been investigated. Nucleic acid hybridisation indicate that both RNAs from RCMV-Uk are highly homologous to their counterparts from RCMV strain S, a conclusion supported by protein sequence analysis of the two viral capsid proteins. Nucleic acid sequence analysis of a portion of RCMV-Uk RNA2 confirmed the high degree of similarity between RCMV-Uk and RCMV strain S. This information suggests that RCMV-Uk should be considered an isolate of RCMV strain S. 相似文献
88.
α2 -Adrenergic receptor agonists are widely used in veterinary medicine as sedative/hypnotic agents. Four pharmacological subtypes of the α2 -adrenergic receptor (A, B, C and D) have been identified based primarily on differences in affinity for several drugs. The purpose of this study was to examine the affinities of the sedative agents, xylazine, detomidine and medetomidine at the four α2 -adrenergic receptor subtypes. Saturation and inhibition binding curves were performed in membranes of tissues containing only one subtype of a2 -adrenergic receptor. The KD for the α2 -adrenergic receptor radioligand, [3 H]-MK-912, in HT29 cells (α2A -), neonatal rat lung (α2B -), OK cells (α2C -) and PC12 cells transfected with RG20 (α2D -) were 0.38 ± 0.08 n m , 0.70 ± 0.5 n m , 0.07 ± 0.02 n m and 0.87 ± 0.03 n m , respectively. Detomidine and medetomidine had approximately a 100 fold higher affinity for all the α2 -adrenergic receptors compared to xylazine but neither agonist displayed selectivity for the α2 -adrenergic receptor subtypes. These data suggest that available sedative/hypnotic α2 -adrenergic receptor agonists can not discriminate between the four known α2 -adrenergic receptor subtypes. 相似文献
89.
云南省生物资源开发创新产业信息网络建设 总被引:3,自引:1,他引:2
本文简单介绍了云南省生物资源开发创新产业信息网络建设规划研究和实施情况 ,如网络设计目标、体系结构选择、信息资源建设规划、网络的搭建以及数据库的建设构想等 相似文献
90.
Nigel G. Clark 《Pest management science》1985,16(1):23-32
A variety of 2-amino-, 2-anilino- and 2-acylamino-1, 4-naphthoquinones, with hydrogen, chlorine, alkoxy, phenoxy, methylthio or phenylthio as the 3-substituent, have been synthesised and assayed against Botrytis cinerea, Cladosporium fulvum and Venturia inaequalis. With few exceptions, only the 2-acylamino compounds possessed appreciable fungicidal activity: this was of a high order in the cases of 2-prop-ionamido-, 2-N-methylacetamido-3-methylthio-, and 3-methoxy-2-N-methylacetamido-1, 4-naphthoquinones. 相似文献