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John E. Moore Yasunori Maeda Jiru Xu B. Cherie Millar Peter H. Herold V. M. J. Browne-Lauwers Colin E. Goldsmith Anne Loughrey Paul J. Rooney J. Stuart Elborn Motoo Matsuda 《World journal of microbiology & biotechnology》2008,24(7):1227-1232
To employ 16S rDNA PCR and automated sequencing techniques to identify a collection of bacterial veterinary pathogens from
avian, equine, canine and ovine sources, that have proven difficult to identify, employing conventional cultural techniques.
Universal or “broad-range” eubacterial PCR was performed on a collection of 46 difficult-to-identify bacterial isolates originating
from clinical veterinary specimens. 16S rDNA PCR was performed using two sets of universal primers to successfully generate
a composite amplicon of 1,068 bp, which was sequenced to obtain each isolate’s identity. Sequence analysis was able to identify
all isolates examined with relative ease. Where the use of molecular identification methods is justified, such as in outbreak
control or bioterrorism in animal health, employment of partial 16S rDNA PCR and sequencing employing universal or “broad-range”
16S rDNA, provides a valuable and reliable method of identification of such pathogens. 相似文献
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McKeown SC Hall A Giblin GM Lorthioir O Blunt R Lewell XQ Wilson RJ Brown SH Chowdhury A Coleman T Watson SP Chessell IP Pipe A Clayton N Goldsmith P 《Bioorganic & medicinal chemistry letters》2006,16(18):4767-4771
The discovery, synthesis and structure-activity relationship (SAR) of a novel series of EP1 receptor antagonists is described. Pyrazole acid 4, identified from a chemical array, had desirable physicochemical properties, an excellent in vitro microsomal inhibition and cytochrome P450 (CYP450) profile and good exposure levels in blood. This compound had an ED50 of 1.3 mg/kg in a rat pain model. A range of more potent analogues in the in vitro assay was identified using efficient array chemistry. These EP1 antagonists have potential as agents in the treatment of PGE2 mediated pain. 相似文献
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J L Meinkoth P K Goldsmith A M Spiegel J R Feramisco G N Burrow 《The Journal of biological chemistry》1992,267(19):13239-13245
Thyrotropin (TSH) is an important regulator of thyroid follicular cells. While its role in the maintenance of differentiated functions is undisputed, its role as a mitogen is less clear. TSH induces DNA synthesis and cell proliferation in some cells, while in others, TSH is mitogenic only in the presence of additional growth factors such as insulin-like growth factor-1. TSH causes elevations in intracellular cAMP and is thought to utilize this second messenger system in its mitogenic action. We studied TSH as a mitogen in Wistar rat thyroid cells (WRT) (Brandi, M. L., Rotella, C. M., Mavilia, C., Franceschelli, F., Tanini, A., and Toccafondi, R. (1987) Mol. Cell. Endocrinol. 54, 91-103) and examined the role of the guanine nucleotide binding protein, Gs, in its mitogenic action. WRT cells synthesized DNA in response to TSH and elevations in cAMP. In addition, TSH caused a rapid stimulation of an indicator gene whose expression is regulated by cAMP response elements. Following microinjection of an inhibitory polyclonal antibody raised against the Gs protein, both TSH-induced changes in gene expression and DNA synthesis were significantly reduced. These results demonstrate that virtually all of the mitogenic action of TSH is transduced through the Gs protein in WRT cells, presumably through the regulation of adenylate cyclase. Whether all or only part of TSH action is mediated by cAMP and the cAMP-dependent protein kinase remains to be determined. 相似文献
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目的:探讨利用分子量阵列平台进行特定序列甲基化分析的方法。方法:通过对不同扩增条件和扩增效率及不同条件处理的质谱分析比较了MassArray平台进行甲基化分析的特点。结果:本研究通过与重亚硫酸盐测序结果比较证实,MassArray分子量阵列技术平台能够反映甲基化修饰的真实水平;通过不同条件下PCR扩增效率与甲基化分析的结果,发现扩增效率是制约MassArray分子量阵列技术平台甲基化分析的关键因素,而产物的放置时间和不同的处理没有明显影响甲基化分析。结论:Mas-sArray甲基化分析平台是高效快速检测甲基化修饰的平台,在使用过程中应该根据实际的实验条件,进行合理的质控。 相似文献
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干旱是影响燕山地区板栗树生长和产量的主要因子。为了在整株水平上研究板栗幼苗对干旱胁迫的响应,本试验以盆栽\"燕山早丰\"板栗幼苗为研究对象,通过模拟自然干旱处理22 d,测定叶片光合特性,根、茎、叶生物量、脯氨酸、丙二醛、碳、氮等生理指标变化。结果表明:与正常浇水相比,干旱胁迫下幼苗根、茎、叶含水量分别显著下降18.3%、29.0%和62.8%,脯氨酸(355.0%~1586.7%)和丙二醛(41.1%~81.3%)含量显著上升(茎中丙二醛除外),但叶部非光化学淬灭系数和净光合速率分别显著下降49.4%和77.4%;同时,茎和叶中非结构碳水化合物含量分别显著增加21.4%和69.5%,根中增加幅度未达显著差异水平;根和叶中硝态氮含量分别显著增加28.9%和26.8%,茎中增加幅度未达显著差异水平;根、茎、叶中铵态氮含量分别增加了16.2%、12.9%、217.6%,但仅在叶部差异显著。综上,干旱胁迫对燕山早丰板栗幼苗产生了较严重的伤害,显著抑制了其光合性能,但能够通过增强体内碳氮代谢来提高其适应干旱环境的能力。本研究结果可为当地板栗抗旱性资源选育和栽培提供参考。 相似文献