DGGE和qPCR联用定量分析环境样品中优势菌群

精确定量环境样品中特定微生物类群的数量对阐明环境生物治理/修复过程中微生物的功能和效应具有重要意义.该文以土壤样品为例,将PCR-DGGE技术与定量PCR(qPCR)技术联用,定量检测样品中优势微生物类群数量.方法:抽提样品DNA,针对16S rDNA进行PCR-DGGE分析,明确样品中的优势菌群;再根据特定优势菌群的基因序列设计适合的定量引物,通过针对特定优势菌群的定量PCR分析,得到样品中优势菌群的数量信息.该方法灵敏度高、重复性好,并且无需培养,最大限度地保持了样品原始群落信息.     

荧光定量聚合酶链反应检测尿中乙肝病毒DNA的意义

目的:研究乙肝携带者尿液HBVDNA含量及传染性.方法:用荧光定量聚合酶链反应(FQ-PCR)检测50例患者血清乙肝病毒DNA含量大于104拷贝/ml患者尿液中乙肝病毒DNA含量比较.结果:尿中HBV-DNA含量与血清中HBV-DNA含量存在正相关关系(r=0.797,p0.01).结论:血清中HBV-DNA含量拷贝数越大,尿液中HBV-DNA含量拷贝数也越大,HBV-DNA拷贝数高的患者注意尿液的传染性.     

进样口温度对顶空-气相色谱法测定包装纸中挥发性有机化合物的影响

在气相色谱仪进样口设置不同的温度时,对同一种包装纸样品中挥发性有机化合物进行定量分析,以判定进样口温度对定量结果的影响.其结果表明:不同的进样口温度,对同一样品中的挥发性有机化合物的测定结果影响很小.     

单细胞测序在肿瘤研究中的应用

肿瘤是一种基因疾病,其发病机制包括单核苷酸突变、拷贝数变异、插入/缺失等。人类对肿瘤经过数十年的研究,未获得突破性进展。肿瘤研究的关键是理解基因的改变在肿瘤发生、发展过程中发挥的作用。近些年单细胞测序技术的发展为探寻肿瘤发生中基因的改变提供了有力的工具。现通过肿瘤标志运用流式细胞术分选单个肿瘤细胞,并通过细胞测序获得大量信息,为肿瘤的治疗提出一个新方法—个体化治疗。     

基因拷贝数变异研究进展

基因拷贝数变异（CNVs）是一种大小介于1kb到3Mb之间的DNA片段的缺失、重复、倒位和易位,广泛存在于基因组中,被认为是个体间基因差异的重要来源。本文从CNVs的发现、形成机制、与疾病的关系以及研究前景几个方面综述了CNVs的研究进展。     

实时荧光定量PCR技术的操作实践

采用Mx3000P型实时荧光定量PCR仪,以SYBR(R) Green I法相对定量技术为例,设计1例检测针对HIV-1 vpr基因的特异性siRNA基因沉默效果的实验.介绍了实时荧光定量PCR技术上机前样本的制备过程、检测程序及相关参数的设置方法等操作流程;结合熔解曲线、扩增曲线进行结果分析;强调了实验整体设计、引物设计与PCR反应体系的优化和内参的恰当选择在实时荧光定量PCR技术中的重要性.     

两例无关的罕见I型Crigler-Najjar综合征患者:两种新突变和一例患者UGT1A1基因杂合性缺失(英文)

研究目的:I型Crigler-Najjar综合征(CN-I)为先天性间接胆红素血症的最严重的一种,是由位于染色体2q37的葡萄糖醛酸转移酶基因(UGT1A1)的纯合或复合杂合突变引起的一种罕见的遗传性疾病。本研究对来自两个无关家庭的两例临床诊断为CN-I的患儿及父母进行UGT1A1基因分子遗传学分析。研究方法:经知情同意后,采集两例患儿及父母外周血;聚合酶链式反应(PCR)扩增UGT1A1基因5个外显子及外显子-内含子交界处,进行测序分析。应用实时定量PCR(qRT-PCR)测定其中一例患者UGT1A1基因的拷贝数。重要结论:本研究在两例CN-I型患儿中检测到3个UGT1A1基因突变:c.239_245delCTGTGCC(p.Pro80HisfsX6)、c.1253delT(p.Met418ArgfsX5)和c.1156GT(p.Val386Phe)。前两个突变均为新发的移码突变,预测提前出现终止密码或诱发RNA降解;而突变c.1156GT(p.Val386Phe)的致病机制尚需进一步研究。     

活性污泥中氨氧化菌实时荧光定量PCR标准品制备方法的比较

为了快速准确地检测活性污泥中氨氧化菌(AOB)的拷贝数,探求一种新的快速简便的绝对定量标准品的制备方法。利用纯化的PCR产物和重组质粒标准品分别进行绝对定量,比较两者熔解曲线、扩增曲线、标准曲线和绝对拷贝数等方面的差异,分析两种标准品制备方法应用方面的优势。结果显示,两种标准品制备的熔解曲线都呈单一尖峰、扩增曲线指数期平行、标准曲线R299%,PCR产物作为标准品得到的AOB绝对拷贝数小于质粒标准品的结果(P0.05),表明纯化的PCR产物作为标准品较制备重组质粒标准品而言,操作过程更加简便、经济、对人员专业要求更低,在其纯度较高的情况下,具有和重组质粒标准品一样的应用效果。     

5025例新生儿药物性耳聋基因突变筛查结果分析

通过对莆田地区新生儿药物性耳聋基因线粒体12S r RNA突变的检测结果进行分析,为预防莆田地区新生儿的药物性耳聋提供支持。对5025例新生儿采用多重Taq Man荧光PCR基因拷贝数定量检测技术进行耳聋基因线粒体12S r RNA的检测,检测位点包括A1555G和C1494T。结果,5025例新生儿耳聋基因检测中共发现7例12S r RNA A1555G纯合突变,未发现12S r RNA C1494T突变,突变比例为0.14%。结果表明,提倡新生儿药物性耳聋基因线粒体12S r RNA的检测,对预防药物性耳聋具有显著临床意义。     

癌细胞生存基因图谱

<正>在最新的研究中,由美国哈佛-麻省理工的博德研究所和达纳法伯癌症研究所的科学家们领导的一个研究小组确定了56个癌细胞生存的必要基因,或可代表治疗开发可利用的靶点。相关论文"CancerVulnerabilities Unveiled by Genomic Loss."发表在2012年8月17日的《细胞》(Cell)杂志上。在每一种情况下由于基因组不稳定造成的拷贝数丢失,只有一个拷贝的靶基因存在于癌细胞中。对于每个经确定的基因,抑制癌症中剩余的拷贝会导致细胞死亡或阻断增殖。并且不同于驱动癌症增殖的经典癌基因,大部分新发现的靶点在基础的细胞过程和包括剪接体、糖核体和蛋白酶体在内的结构中发挥     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…     

库克斯顿城堡

城堡, 是欧洲典型的建筑之一, 每个城堡都有一个美丽的传说或是一段历史。从本期开始, 我们将推出“城堡之旅”, 带各位读者去浏览、观赏欧洲各地的城堡, 开始一段文化与历史的旅途!     

The Reader Response Approach to Teaching of English Literature

During interview with English majors, it was found that a majority of students expressed disappointment with their experience of English literature classes. Students' dislike of learning English literature appears to be the major problem of teaching English literature in China. Reader response approach is a good way to solve this problem. In this paper, I explain the rationale behind the reader response approach, such as its origin, definition, features, assumptions, and strategies. Then I illustrate how reader response approach works as a teaching strategy by presenting several teaching models. At last I evaluate its usefuiness for teachers and present the advantages of reader response approach in Chinese context.