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使用PCR检测角膜绿脓杆菌(英文)

国际眼科杂志 2011年第7期11卷 1125-1131页

作者： maria E.Hillenbrand Paul P.Thompson robert m.q.shanks Regis P.Kowalski 美国宾夕法尼亚州匹兹堡大学医学院眼科及视觉科学研究中心UPMC眼科中心The Charles T.Campbell.眼科微生物学实验室

目的:确定一个种特异性的实时聚合酶链反应(PCR)法检测绿脓杆菌(PA),一个可能提供给其他细菌病原体通用目标的用于PA的次一级目标DNA,并验证这种用于诊断测试的检测方法。方法:利用已知PA的角膜炎株建立对ecfXPA基因和16SrRNA基因的PCR... 详细信息

目的:确定一个种特异性的实时聚合酶链反应(PCR)法检测绿脓杆菌(PA),一个可能提供给其他细菌病原体通用目标的用于PA的次一级目标DNA,并验证这种用于诊断测试的检测方法。方法:利用已知PA的角膜炎株建立对ecfXPA基因和16SrRNA基因的PCR检测。两个实验的结果参数是"检测限"(LOD),扩增效率(AE)和聚丙烯酰胺凝胶电泳(PAGE)扩增产物分析。两种检测方法通过对20例PADNA阳性的真阳性临床标本和20例不含有PADNA的真阴性样品的检测进行了验证。描述性统计和PAGE分析用作为结果参数。结果:通过ecfX检测的AE为96.6%,而LOD为每微升33.6目标DNA拷贝。16SrRNA检测的AE为103.4%,而LOD为每微升8.12拷贝。ecfX和16SrRNA检测的敏感性,特异性,阳性预测值,阴性预测值,效率分别为(75%,95%,94%,79%和85%),及(70%,100%,100%,77%和85%)。这两种PCR方法经过了验证,通过了PAGE分析的DNA图谱确认。结论:这里描述的PCR方法可能是对PA角膜炎标准诊断方法的一种有用的辅助检测。

关键词：绿脓杆菌角膜实时聚合酶链反应 ecfX 16S rRNA

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有机橡胶助剂的全分析

光谱学与光谱分析 2010年第3期30卷 654-658页

作者：何文绚 robert shanks 游叶明闽江学院化学与化学工程系福建福州350108 澳大利亚皇家墨尔本理工大学应用科学学院澳大利亚墨尔本Vic．3001

橡胶产品中橡胶助剂的分析有重要现实意义。由于橡胶产品中添加的助剂种类较多,添加量差别较大,部分助剂又已发生反应,因此进行橡胶助剂的全分析是一项有较高难度的工作。通过中压色谱分离,红外光谱定性的方法,鉴定了乙丙橡胶助剂中的... 详细信息

橡胶产品中橡胶助剂的分析有重要现实意义。由于橡胶产品中添加的助剂种类较多,添加量差别较大,部分助剂又已发生反应,因此进行橡胶助剂的全分析是一项有较高难度的工作。通过中压色谱分离,红外光谱定性的方法,鉴定了乙丙橡胶助剂中的矿物油、邻苯二甲酸酯、植物油等3种软化剂,以及残余的硫化促进剂m和防老化剂苯乙烯化苯酚;采用固相萃取去除助剂中主量成分矿物油,以减少对其他少量助剂成分的干扰,通过气质联用法,推测出橡胶助剂中的2,6-二叔丁基-4-甲基苯酚防老剂、残余的秋兰姆类硫化促进剂,同时利用气质联用仪,直接测定乙丙橡胶抽提液,鉴定了残余的活泼性物质过氧化苯甲酰类硫化剂。文章研究结果可供其他橡胶体系有机助剂全分析的借鉴。

关键词：橡胶助剂红外光谱气质联用中压色谱

The LysR Transcription Factor, HexS, Is Required for Glucose Inhibition of Prodigiosin Production by <i>Serratia marcescens</i>

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Advances in microbiology 2012年第4期2卷 511-517页

作者： Nicholas A. Stella James E. Fender Roni m. Lahr Eric J. Kalivoda robert m. q. shanks Charles T. Campbell Laboratory of Ophthalmic microbiology Department of Ophthalmology University of Pittsburgh Pittsburgh USA College of medicine University of Vermont Burlington USA

Generation of many useful microbe-derived secondary metabolites, including the red pigment prodigiosin of the bacterium Serratia marcescens, is inhibited by glucose. In a previous report, a genetic approach was used to determine that glucose dehydrogenase activity (GDH) is required for inhibiting prodigiosin production and transcription of the prodigiosin biosynthetic operon (pigA-N). However, the transcription factor(s) that regulate this process were not characterized. Here we tested the hypothesis that HexS, a LysR-family transcription factor similar to LrhA of Escherichia coli, is required for inhibition of prodigiosin by growth in glucose. We observed that mutation of the hexS gene in S. marcescens allowed the precocious production of prodigiosin in glucose-rich medium conditions that completely inhibited prodigiosin production by the wild type. Unlike previously described mutants able to generate prodigiosin in glucoserich medium, hexS mutants exhibited GDH activity and medium acidification similar to the wild type. Glucose inhibittion of pigA expression was shown to be dependent upon HexS, suggesting that HexS is a key transcription factor in secondary metabolite regulation in response to medium pH. These data give insight into the prodigiosin regulatory pathway and could be used to enhance the production of secondary metabolites.

关键词： Pigment Antibiotic Transcription Factor Secondary metabolite

modulated Transmission Property of Bacteriorhodopsin Film and Its Application on Thresholding Operation

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Chinese Physics Letters 1998年第11期15卷 799-801页

作者： LI Yu-dong SUN qian ZHANG Chun-ping LU Rui FU Guang-hua ZHANG Guang-yin SONG q.Wang Bruce Parsons robert R.Birge Department of Physics Nankai UniversityTianjin 300071 W.m.Keck Center for molecular Electronics Syracuse UniversitySyracuseNY 13244U.S.A.

In this paper,the modulated transmission property of bacteriorhodopsin(bR)film is analyzed theoretically when two beams of light,yellow light and purple light,illuminate the bR film *** using the transmission property... 详细信息

关键词： film property yellow

Expression levels of aminopeptidase-N genes in the lightbrown apple moth, Epiphyas postvittana

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Insect Science 2008年第6期15卷 505-512页

作者： robert m. Simpson Joanne Poulton Ngaire P. markwick Horticulture and Food Research Institute Palmerston North Horticulture and Food Research Institute Auckland New Zealand

Five aminopeptidase-N genes （EpAPN1-5） of the tortricid moth Epiphyas postvittana have been isolated from a midgut expressed sequence tag （EST） library. Relative RNA expression of these genes was measured by quantitative reverse transcription polymerase chain reaction using actin as a reference gene. measurements were made on various tissues of fifth instar larvae, over all stages of the life cycle and under differing dietary conditions： different protein sources and levels, and in presence of trypsin and metalloprotease inhibitors. Gene expression for all five genes was the greatest in midgut tissue, but was also detected in the hindgut, fat body and malpighian tubules. EpAPN4 was consistently the highest expressed, with EpAPN3 at about half that level; EpAPN5 was the least expressed. During larval stages expression was high, generally increasing over the instars, after an early peak as neonates or first instars. Expression in other life stages was much lower. males and females showed differing expression in the pupal and adult stages： female expression was higher in the pupa, this reversed in the adult. Gene expression levels and ratios both changed with diet. A natural apple leaf diet depressed levels. Diets with the most impaired amino acid balance induced the greatest change; generally EpAPN1 increased by the greatest proportion. The addition of proteinase inhibitor also increased gene expression, and it was noteworthy that the trypsin inhibitor addition, which has been shown to double aminopeptidase activity, also doubled levels of gene expression.

关键词： aminopeptidase Epiphyas postvittana q-PCR

Impact of bolus volume on small intestinal intra-luminal impedance in healthy subjects

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World Journal of Gastroenterology 2010年第17期16卷 2151-2157页

作者： Nam q Nguyen Laura K Bryant Carly m Burgstad robert J Fraser Daniel Sifrim Richard H Holloway Department of Gastroenterology & Hepatology Royal Adelaide HospitalAdelaide 5000Australia Investigation and Procedures Unit Repatriation General HospitalDaw Park 5041Australia Department of medicine Centre for Gastroen-terological ResearchK.U.LeuvenLeuven 3000Belgium

AIm: To assess the impact of bolus volume on the characteristics of small intestinal (SI) impedance ***: Concurrent SI manometry-impedance measurements were performed on 12 healthy volunteers to assess the pattern of proximal jejunal fluid bolus movement over a 14 *** subject was given 34 boluses of normal saline (volume from 1 to 30 mL) via the feeding tube placed immediately above the proximal margin of the studied segment.A bolus-induced impedance event occurred if there was > 12% impedance drop from baseline,over ≥ 3 consecutive segments within 10 s of bolus injection.A minor or major imped-ance event was defined as a duration of impedance drop minimum volume required for a detectable SI impedance event was 2 mL.A direct linear relationship between the SI bolus volume and the occurrence of impedance events was noted until SI bolus volume reached 10 mL,a volume which always produced an impedance flow *** was a moderate correlation between the bolus volume and the duration of impedance drop (r = 0.63,P mber of propagated channels (r = 0.50,P me boluses were associated with more major impedance events (≥ 10 mL boluses = 63%,3 mL boluses = 17%,and mL boluses = 0%,P = 0.02).CONCLUSION: Bolus volume had an impact on the type and length of propagation of SI impedance events and a threshold of 2 mL is required to produce an event.

关键词： Bolus volume Health Impedance Luminal flow Small intestine

Annealing-induced Hardening in a Nanostructured Low-carbon Steel Prepared by Using Dynamic Plastic Deformation

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Journal of materials Science & Technology 2014年第8期30卷 731-735页

作者： L.X.Sun N.R.Tao m.Kuntz J.q.Yu K.Lu Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of Sciences Corporate Sector Research and Advance Engineering Production Technology 1 Materials and Process Engineering MetalsRobert Bosch GmbHP. O. Box 30 02 4070442 StuttgartGermany Research and Technology Center Asia Pacific Bosch(China) Investment Ltd.

Lamellar nanostructures were induced in a plain martensitic low-carbon steel by using dynamic plastic deformation at room *** nanostructured steel was hardened after annealing at 673 K for20 min,with a tensile strength increased from 1.2 GPa to 1.6 *** the remained nanostructures and annealing-induced precipitates in nano-scale play key roles in the hardening.

关键词： Nanostructure Annealing Precipitation hardening Low-carbon steel Dynamic plastic deformation

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Behave

Behave

Genome-wide association analysis reveals regulation of at-risk loci by DNA methylation in prostate cancer

作者： robert m. Sapolsky.

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Asian Journal of Andrology 2021年第5期23卷 472-478页

作者： qiang Liu Gang Liu Darryl T martin Yu-Tong Xing robert m Weiss Jun qi Jian Kang Department of Urology Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China Department of Urology Yale University School of MedicineNew HavenCT 06510USA Key Lab of Systems Biology Shanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China Institute of Estuarine and Coastal Research East China Normal UniversityShanghai 20CXD62China

Epigenetic changes are potentially important for the ontogeny and progression of tumors but are not usually studied because of the complexity of analyzing transcript regulation resulting from epigenetic *** cancer(PCa)is characterized by variable clinical manifestations and frequently unpredictable *** performed an expression quantitative trait loci(eqTL)analysis to identify the genomic regions that regulate gene expression in PCa and identified a relationship between DNA methylation and clinical *** multi-level information published in The Cancer Genome Atlas,we performed eqTL-based analyses on DNA methylation and gene *** better interpret these data,we correlated loci and clinical indexes to identify the important loci for both PCa development and *** data demonstrated that although only a small proportion of genes are regulated via DNA methylation in PCa,these genes are enriched in important cancer-related *** addition,single nucleotide polymorphism analysis identified the locations of CpG sites and genes within at-risk loci,including the 19q13.2-q13.43 and 16q22.2-q23.1 ***,an epigenetic association study of clinical indexes detected risk loci and pyrosequencing for site *** DNA methylation-regulated genes across PCa samples are a small proportion,the associated genes play important roles in PCa carcinogenesis.

关键词： CpG sites DNA methylation expression quantitative trait loci genome-wide association study prostate cancer