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利用重组反转录病毒表达马立克氏病病毒Meq基因

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中国兽医学报 1999年第2期19卷 105-108页

作者：韦平 Luck f.Lee 广西大学动物科技学院美国农业部禽病与肿瘤研究所

为研究马立克氏病病毒（ＭＤＶ）Ｍｅｑ蛋白的生物学功能，应用磷酸钙与ＭＤＶＭｅｑ基因重组的反转录病毒转染载体质粒ＲＣＡＳ－Ｍｅｑ的ＤＮＡ，转染于鸡胚成纤维细胞系ＤＦ１。经间接免疫荧光技术研究表明，转染后第３天即开始有少... 详细信息

为研究马立克氏病病毒（ＭＤＶ）Ｍｅｑ蛋白的生物学功能，应用磷酸钙与ＭＤＶＭｅｑ基因重组的反转录病毒转染载体质粒ＲＣＡＳ－Ｍｅｑ的ＤＮＡ，转染于鸡胚成纤维细胞系ＤＦ１。经间接免疫荧光技术研究表明，转染后第３天即开始有少量ＤＦ１细胞在细胞核表达Ｍｅｑ蛋白，以后阳性细胞增多，到转染后第７天阳性细胞最多，之后荧光即衰减；通过酶联免疫吸附试验检测，发现细胞培养上清中游离病毒在转染后第５天即可检出，直至第７天仍维持最高水平，第９天开始下降。用细胞培养上清感染ＤＦ１细胞单层，于感染后第２天即可检出Ｍｅｑ蛋白阳性细胞，之后阳性细胞逐渐增多，到第４～５天达高峰，之后逐渐衰减；培养上清中的游离病毒在感染后第４天即可被检出，第５～７天达最高值。研究结果表明：（１）磷酸钙法能很好地将重组质粒ＲＣＡＳ－ＭｅｑＤＮＡ转染到ＤＦ１细胞中，而对细胞的损伤很小；（２）转染后细胞释放出的重组病毒能感染ＤＦ１细胞并稳定地表达Ｍｅｑ蛋白。表明Ｍｅｑ基因在构建的重组病毒基因组中的存在及其转录表达都是稳定的。这为在体内和体外研究ＭＤＶＭｅｑ基因的生物学功能提供了一种非常有效的方法和途径；（３）Ｍｅｑ蛋白仅分布于细胞核（包括核质和核仁）。这一结果证实了?

关键词：马立克氏病病毒 Meq基因 RCAS 重组转染

Review of the evidence for the management of co-morbid Tic disorders in children and adolescents with attention deficit hyperactivity disorder

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World Journal of Clinical Pediatrics 2018年第1期7卷 36-42页

作者： Michael O Ogundele Hani f Ayyash Department of Community Paediatrics NHS Fife Glenwood Health Centre Cambridgeshire and Peterborough NHS foundation Trust Peterborough Integrated Neurodevelopmental ServiceUniversity of Cambridge Health Partners

Attention deficit hyperactivity disorder(ADHD) is the most common neurodevelopmental disorder in children and adolescents, with prevalence ranging between 5% and 12% in the developed countries. Tic disorders(TD) are common co-morbidities in paediatric ADHD patients with or without pharmacotherapy treatment. There has been conflicting evidence of the role of psychostimulants in either precipitating or exacerbating TDs in ADHD patients. We carried out a literature review relating to the management of TDs in children and adolescents with ADHD through a comprehensive search of MEDLINE, EMBASE, CINAHL and Cochrane databases. No quantitative synthesis(meta-analysis) was deemed appropriate. Metaanalysis of controlled trials does not support an association between new onset or worsening of tics and normal doses of psychostimulant use. Supratherapeutic doses of dextroamphetamine have been shown to exacerbate TD. Most tics are mild or moderate and respond to psychoeducation and behavioural management. Level A evidence support the use of alpha adrenergic agonists, including Clonidine and Guanfacine, reuptake noradrenenaline inhibitors(Atomoxetine) and stimulants(Methylphenidate and Dexamphetamines) for the treatment of Tics and comorbid ADHD. Priority should be given to the management of co-morbid Tourette's syndrome(TS) or severely disabling tics in children and adolescents with ADHD. Severe TDs may require antipsychotic treatment. Antipsychotics, especially Aripiprazole, are safe and effective treatment for TS or severe Tics, but they only moderately control the co-occurring ADHD symptomatology. Short vignettes of different common clinical scenarios are presented to help clinicians determine the most appropriate treatment to consider in each patient presenting with ADHD and co-morbid TDs.

关键词： Tics disorders Childhood Attention deficit hyperactivity disorder Adolescence Tourette’s syndrome

Investigation on the formation of Herringbone Structure in TypeⅡSolar Radio Bursts

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Research in Astronomy and Astrophysics 2023年第5期23卷 101-109页

作者： Z.Z.Abidin A.N.Zulkiplee V.Epin f.A.M.Pauzi Radio Cosmology Research Lab Physics Dept.Faculty of ScienceUniversity of MalayaKuala LumpurMalaysia

We report detailed observation of the“herringbone”of a Type II solar radio burst that occurred on 2010 November *** from the Space Weather Prediction Center,National Oceanic and Atmospheric Administration,e-CALLISTO,and Nan?ay Radio Heliograph are *** determine the brightness temperature and degree of circular polarization of the“herringbone”*** between the physical parameters and the“herringbone”are *** on the relationship,this is the first study that suggested this“herringbone”was generated through fundamental plasma.

关键词： Sun activity-Sun corona-Sun coronal mass ejections(CMEs)-Sun magnetic fields-Sun radio radiation

Did maize domestication and early spread mediate the population genetics of corn leafhopper?

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Insect Science 2019年第3期26卷 569-586页

作者： Julio S. Bernal Amanda M. Davila-flores Raul f. Medina Yolanda H. Chen Kyle E. Harrison Kimberly A. Berrier Department of Entomology Texas A&M University College Station Texas USA Department of Plant and Soil Sciences University of Vermont Burlington Vermont USA

Investigating how crop domestication and early farming mediated crop attributes, distributions, and interactions with antagonists may shed light on today's agricultural pest problems. Crop domestication generally involved artificial selection for traits desirable to early farmers, for example, in creased productivity or yield, and enhanced qualities, though invariably it altered the interactions between crops and insects, and expanded the geographical ranges of crops. Thus, some studies suggest that with crop domestication and spread, insect populations on wild crop ancestors gave rise to pestiferous insect populations on crops. Here, we addressed whether the emergence of corn leafhopper (Dalbulus ma id is) as an agricultural pest may be associated with domestication and early spread of maize (Zea mays mays). We used AfLP markers and mitochondrial COI sequences to assess population genetic structuring and haplotype relationships among corn leafhopper samples from maize and its wild relative Zea diploperennis from multiple locations in Mexico and Argentina. We uncovered seven corn leafhopper haplotypes contained within two haplogroups, one haplogroup containing haplotypes associated with maize and the other containing haplotypes associated with Z. diploperennis in a mountainous habitat. Within the first haplogroup, one haplotype was predominant across Mexican locations, and another across Argentinean locations;both were considered pestiferous. We suggested that the divergence times of the maize-associated haplogroup and of the "pestiferous" haplotypes are correlated with the chronology of maize spread following its domestication. Overall, our results support a hypothesis positing that maize domestication favored corn leafhopper genotypes preadapted for exploiting maize so that they became pestiferous, and that with the geographical expansi on of maize farming, corn leafhopper colonized Z. diploperennis, a host exclusive to secluded habitats that serves as a refuge fo

关键词： Dalbulus maidis haplotype network analysis perennial teosinte population genetic structuring Zea diploperennis Zea mays mays

Blood flow Simulation in the femoral Artery

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Journal of Electronic Science and Technology 2018年第3期16卷 269-279页

作者： Camilo A.Naranjo Andrés f.Villa Juan C.Vélez Ricardo A.Prato Alberto J.Cadena Juan P.Tello IPATEC Institute CONICETBariloche R8400 Integra IT Bogotá 602 the Electronic and Electric Engineering Department Universidad del NorteBarranquilla 1569 the Institute of Mathematics Universidad de AntioquiaMedellin 050010 the Cardiology Department Clínica de la CostaBarranquilla 080020

This paper presents the development of the blood flow simulation in two dimensions over the real geometry of the femoral artery. The Navier-Stokes equations are solved using the finite element method, to obtain the distributions of the blood pressure and flow velocity in multiple instants of time and different places of the femoral artery and thus determine the current condition of the blood vessels. The velocity field shows a laminar behavior,where, the velocity is higher in the center of the artery and decreases as the blood flow approaches artery walls. In spite of all artery and blood flow properties not being considered, the values of pressure and velocity obtained are within the normal ranges. finally the model is used to verify if there exist irregularities in the blood flow in both healthy subjects and sick patients.

关键词： Blood flow femoral artery finite elements Navier-Stokes pressure velocity

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Additive Protective Effects of Luteolin and Pyruvate against 6-Hydroxydopamine and 3-Hydroxykynurenine Induced Neurotoxicity in SH-SY5Y Cells

2017年

作者： (美)f. S.菲茨杰拉德

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Pharmacology & Pharmacy 2013年第4期4卷 369-376页

作者： Natalia Wszelaki Matthias f. Melzig Institut fur Pharmazie/Pharmazeutische Biologie Freie Universitat Berlin Berlin Germany

Oxidative stress has been implicated as one of the causes in cell death in many neurodegenerative disorders. Due to antioxidative properties in vitro, the use of flavonoids and other polyphenolic compounds synthesised by plants are considered to be a promising strategy to prevent Alzheimer’s disease and Parkinsons’s disease. In the present study, we tested protective effects of some polyphenols and sodium pyruvate on 6-hydroxydopamine (6-OHDA), salsolinol and 3-hydroxykynurenine (3-HK) induced neurotoxicity in human neuroblastoma SH-SY5Y cells. We found that luteolin prevented from 6-OHDA and 3-HK induced cell viability reduction and that one of the mechanisms involved in the neuroprotective process was the ability to increase the level of cellular ATP. However, luteolin was ineffective against salsolinol-induced toxicity. Neither pre-treatment with flavonoids nor simultaneous addition had any protective effects on 6-OHDA, salsolinol or 3-HK induced neurotoxicity. Interestingly, both pre-treatment and co-treatment with pyruvate provided protection against 6-OHDA, salsolinol or 3-HK induced toxicity. Moreover, luteolin and sodium pyruvate, administered together, acted additively, so to achieve the same effect, lower concentrations were needed. The ability of luteolin and sodium pyruvate to reduce toxicity of 6-OHDA and 3-HK in SH-SY5Y cells may be related to two different neuroprotective mechanisms and the capability to penetrate into the cell.

关键词： flavonoids Oxidative Stress Pyruvate ATP Luteolin Neurotoxicity

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粉末材料压制过程的DEM分析

重庆大学学报（自然科学版） 2007年第7期30卷 1-4页

作者：温彤 COCKS Alan C f 重庆大学机械工程学院重庆400030 Department of Engineering Science University of Oxford

应用离散单元法(DEM)研究了粉末材料在开口容器中受到刚性凸模压制时的流动特点,获得了压制过程中颗粒的运动轨迹、运动速度以及粉末密度分布等重要信息;总结了几种典型的粉末流动模式,并在相关实验中得到了印证,说明了应用DEM分析具有... 详细信息

应用离散单元法(DEM)研究了粉末材料在开口容器中受到刚性凸模压制时的流动特点,获得了压制过程中颗粒的运动轨迹、运动速度以及粉末密度分布等重要信息;总结了几种典型的粉末流动模式,并在相关实验中得到了印证,说明了应用DEM分析具有强剪切行为的粉末流动是可行的,结论可供粉末冶金工艺和模具设计人员参考。

关键词：粉末冶金离散单元法压制成形

A STUDY Of TEMPERATURE-DEPENDENT VALENCE BOND STRUCTURE Of TITANIUM

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Acta Metallurgica Sinica(English Letters) 2007年第1期20卷 27-34页

作者： X.B. Li Y.Q. Xie Y.Z. Nie H.J. Peng H.J. Tao f.X. Yu College of Materials Science and Engineering Central South University Changsha 410083 China

On the basis of energy and shape method for the determination of the valence bond （ VB ） structures of crystal, the valence bond structure of titanium is redetermined at room temperature and calculated in the whole temperature range of 0-1943K. The outer shell electronic distribution of Ti is ec^29907. （sc^0.4980 ＋ dc^2.4927） ef^1.0098 in crystal. The temperature dependences of the VB structures of hcp and bcc phases are the same. The VB structures of hcp and bcc phases monotonically increase or decrease with the increase in temperature, but show discontinuous changes at the phase-transformation temperature 1155K.

关键词： valence bond structure temperature titanium