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构建了含有恶性疟原虫抗原基因 ( AWTE)的真核表达质粒 p CMV- AWTE,以及能在大肠杆菌中得到分泌性表达的原核表达质粒 p MC0 5 ,表达的蛋白 AWTE保持了疟原虫抗原的抗原性。将 p CMV- AWTE以及 AWTE两者混合各 1 0μg鼻腔免疫小鼠 ,一次后诱导机体产生了较高水平的体液免疫及细胞免疫  相似文献   
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Gan  Huijie  Emmett  Bryan D.  Drinkwater  Laurie E. 《Plant and Soil》2021,462(1-2):543-560
Plant and Soil - Agricultural practices often have persistent effects on soil physicochemical properties and soil biota, which can feedback to influence plant performance. We investigated...  相似文献   
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Hepatitis E virus (HEV) is a single-strand positive-sense RNA virus in the family Hepeviridae. The disease caused by HEV, hepatitis E, is an important public health problem in developing countries of Asia and Africa and is also endemic in many industrialized countries, including the United States. HEV has been identified from several other animal species in addition to humans, including the pig, chicken, mongoose, deer, rabbit, ferret, bat, and fish. Here we report the complete genome sequence of the first strain of HEV from rabbits in the United States. Sequence and phylogenetic analyses revealed that the U.S. rabbit HEV is a distant member of the zoonotic genotype 3 HEV, thus raising a concern for potential zoonotic human infection. A unique 90-nucleotide insertion within the X domain of the ORF1 was identified in the rabbit HEV, and this insertion may play a role in the species tropism of HEV.  相似文献   
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Abstract: In this study we examined the effect on oligodendroglial survival of exogenous cystine deprivation. Oligodendroglia isolated from mixed glial primary cultures derived from brains of 1-day-old rats, and then grown for 3 days, were markedly dependent on extracellular cystine for survival. The EC50 values for cystine for a 24-h exposure ranged from 2 to 65 µ M . After 6 h of cystine deprivation, the cellular glutathione level decreased to 21 ± 13% of the control. Free radical scavengers (α-tocopherol, ascorbate, idebenone, and N-tert -butyl-α-phenylnitrone) were protective against cystine deprivation but had no effect on the glutathione level. An iron chelator, desferrioxamine mesylate, also was protective. These findings suggest that intracellular hydroxyl radicals are important for this toxicity. In contrast to the observations in 3-day-old cultures, the dependence on exogenous cystine for cell viability was not observed consistently in oligodendroglia cultured for 6 days before the onset of cystine deprivation. Several observations suggested that this loss of cystine dependence was due to a diffusible factor. Sensitivity to the toxicity of cystine deprivation in day 6 cultures increased as the volume of medium was increased from 0.3 to 2 ml. Furthermore, preincubation of cystine-depleted medium with astrocyte cultures eliminated the toxicity of the cystine deprivation. HPLC assay of the conditioned cystine-depleted medium showed no significant change in cystine or cysteine concentration. We conclude that oligodendroglia are highly susceptible to cystine deprivation in day 3 cultures and that this susceptibility is due to the accumulation of intracellular free radicals in the setting of glutathione depletion. The resistance of day 6 oligodendroglial cultures is caused at least in part by a diffusible factor.  相似文献   
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During the past 40 years, more than 400 Sudden Unexplained Deaths (SUDs) have occurred in Yunnan, southwestern China. Epidemiological and toxicological analyses suggested that a newly discovered mushroom called Trogia venenata was the leading culprit for SUDs. At present, relatively little is known about the genetics and natural history of this mushroom. In this study, we analyzed the sequence variation at four DNA fragments among 232 fruiting bodies of T. venenata collected from seven locations. Our ITS sequence analyses confirmed that all the isolates belonged to the same species. The widespread presence of sequence heterozygosity within many strains at each of three protein-coding genes suggested that the fruiting bodies were diploid, dikaryotic or heterokaryotic. Within individual geographic populations, we found significant deviations of genotype frequencies from Hardy-Weinberg expectations, with the overall observed heterozygosity lower than that expected under random mating, consistent with prevalent inbreeding within local populations. The geographic populations were overall genetically differentiated. Interestingly, while a positive correlation was found between population genetic distance and geographic distance, there was little correlation between genetic distance and barium concentration difference for the geographic populations. Our results suggest frequent inbreeding, geographic structuring, and limited gene flow among geographic populations of T. venenata from southwestern China.  相似文献   
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Ahmed  Imrul Mosaddek  Nadira  Umme Aktari  Cao  Fangbin  He  Xiaoyan  Zhang  Guoping  Wu  Feibo 《Planta》2016,243(4):973-985
Planta - The drought-stimulated gene expression of NCED, SUS, and KS - DHN and ABA signal cross-talk with other phytohormones maintains barley root growth under drought stress at pH 4.0 plus...  相似文献   
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