genepdf

1. 求聚合酶的英文综述或介绍

1

A DNA polymerase is an enzyme that catalyzes the polymerization of deoxyribonucleotides into a DNA strand. DNA polymerases are best-known for their role in DNA replication, in which the polymerase "reads" an intact DNA strand as a template and uses it to synthesize the new strand. The newly-polymerized molecule is complementary to the template strand and identical to the template's original partner strand. DNA polymerases use a magnesium ion for catalytic activity.

DNA polymerase can add free nucleotides to only the 3’ end of the newly-forming strand. This results in elongation of the new strand in a 5'-3' direction. No known DNA polymerase is able to begin a new chain (de novo). DNA polymerase can add a nucleotide onto only a preexisting 3'-OH group, and, therefore, needs a primer at which it can add the first nucleotide. Primers consist of RNA and DNA bases with the first two bases always being RNA, and are synthesized by another enzyme called primase. An enzyme known as a helicase is required to unwind DNA from a double-strand structure to a single-strand structure to facilitate replication of each strand consistent with the semiconservative model of DNA replication.

Error correction is a property of some, but not all, DNA polymerases. This process corrects mistakes in newly-synthesized DNA. When an incorrect base pair is recognized, DNA polymerase reverses its direction by one base pair of DNA. The 3'->5' exonuclease activity of the enzyme allows the incorrect base pair to be excised (this activity is known as proofreading). Following base excision, the polymerase can re-insert the correct base and replication can continue.

DNA polymerases have highly-conserved structure, which means that their overall catalytic subunits vary, on a whole, very little from species to species. Conserved structures usually indicate important, irreplicable functions of the cell, the maintenance of which provides evolutionary advantages.

Some viruses also encode special DNA polymerases, such as Hepatitis B virus DNA polymerase. These may selectively replicate viral DNA through a variety of mechanisms. Retroviruses encode an unusual DNA polymerase called reverse transcriptase, which is an RNA-dependent DNA polymerase (RdDp). It polymerizes DNA from a template of RNA.

2
A polymerase (EC 2.7.7.6/7/19/48/49) is an enzyme whose central function is associated with polymers of nucleic acids such as RNA and DNA. The primary function of a polymerase is the polymerization of new DNA or RNA against an existing DNA or RNA template in the processes of replication and transcription. In association with a cluster of other enzymes and proteins, they take nucleotides from solvent, and catalyse the synthesis of a polynucleotide sequence against a nucleotide template strand using base-pairing interactions.

It is an accident of history that the enzymes responsible for the catalytic proction of other biopolymers are not also referred to as polymerases.

One particular polymerase, from the thermophilic bacterium, Thermus aquaticus (Taq) (PDB 1BGX, EC 2.7.7.7) is of vital commercial importance e to its use in the polymerase chain reaction, a widely-used technique of molecular biology.

Other well-known polymerases include:

Terminal Deoxynucleotidyl Transferase (TDT), which lends diversity to antibody heavy chains
Reverse Transcriptase, an enzyme used by RNA retroviruses like HIV, which is used to create a complementary strand to the preexisting strand of viral RNA before it can be integrated into the DNA of the host cell. It is also a major target for antiviral drugs.

3
RNA polymerase (RNAP or RNApol) is an enzyme that proces RNA. In cells, RNAP is needed for constructing RNA chains from DNA genes as templates, a process called transcription. RNA polymerase enzymes are essential to life and are found in all organisms and many viruses. In chemical terms, RNAP is a nucleotidyl transferase that polymerizes ribonucleotides at the 3' end of an RNA transcript.

Control of the process of gene transcription affects patterns of gene expression and, thereby, allows a cell to adapt to a changing environment, perform specialized roles within an organism, and maintain basic metabolic processes necessary for survival. Therefore, it is hardly surprising that the activity of RNAP is both complex and highly regulated. In Escherichia coli bacteria, more than 100 transcription factors have been identified, which modify the activity of RNAP.

RNAP can initiate transcription at specific DNA sequences known as promoters. It then proces an RNA chain, which is complementary to the template DNA strand. The process of adding nucleotides to the RNA strand is known as elongation; In eukaryotes, RNAP can build chains as long as 2.4 million nucleosides (the full length of the dystrophin gene). RNAP will preferentially release its RNA transcript at specific DNA sequences encoded at the end of genes known as terminators.

Procts of RNAP include:

Messenger RNA (mRNA)—template for the synthesis of proteins by ribosomes.
Non-coding RNA or "RNA genes"—a broad class of genes that encode RNA that is not translated into protein. The most prominent examples of RNA genes are transfer RNA (tRNA) and ribosomal RNA (rRNA), both of which are involved in the process of translation. However, since the late 1990s, many new RNA genes have been found, and thus RNA genes may play a much more significant role than previously thought.
Transfer RNA (tRNA)—transfers specific amino acids to growing polypeptide chains at the ribosomal site of protein synthesis ring translation
Ribosomal RNA (rRNA)—a component of ribosomes
Micro RNA—regulates gene activity
Catalytic RNA (Ribozyme)—enzymatically active RNA molecules
RNAP accomplishes de novo synthesis. It is able to do this because specific interactions with the initiating nucleotide hold RNAP rigidly in place, facilitating chemical attack on the incoming nucleotide. Such specific interactions explain why RNAP prefers to start transcripts with ATP (followed by GTP, UTP, and then CTP). In contrast to DNA polymerase, RNAP includes helicase activity, therefore no separate enzyme is needed to unwind DNA.

Binding and initiation
RNA Polymerase binding in prokaryotes involves the α subunit recognizing the upstream element (-40 to -70 base pairs) in DNA, as well as the σ factor recognizing the -10 to -35 region. There are numerous σ factors that regulate gene expression. For example, σ70 is expressed under normal conditions and allows RNAP binding to house-keeping genes, while σ32 elicits RNAP binding to heat-shock genes.

After binding to the DNA, the RNA polymerase switches from a closed complex to an open complex. This change involves the separation of the DNA strands to form an unwound section of DNA of approximately 13 bp. Ribonucleotides are base-paired to the template DNA strand, according to Watson-Crick base-pairing interactions. Supercoiling plays an important part in polymerase activity because of the unwinding and rewinding of DNA. Because regions of DNA in front of RNAP are unwound, there is compensatory positive supercoils. Regions behind RNAP are rewound and negative supercoils are present.

Elongation
Transcription elongation involves the further addition of ribonucleotides and the change of the open complex to the transcriptional complex. RNAP cannot start forming full length transcripts because of its strong binding to promoter. Transcription at this stage primarily results in short RNA fragments of around 9 bp in a process known as abortive transcription. Once the RNAP starts forming longer transcripts it clears the promoter. At this point, the -10 to -35 promoter region is disrupted, and the σ factor falls off RNAP. This allows the rest of the RNAP complex to move forward, as the σ factor held the RNAP complex in place.

The 17-bp transcriptional complex has an 8-bp DNA-RNA hybrid, that is, 8 base-pairs involve the RNA transcript bound to the DNA template strand. As transcription progresses, ribonucleotides are added to the 3' end of the RNA transcript and the RNAP complex moves along the DNA. Although RNAP does not seem to have the 3'exonuclease activity that characterizes the proofreading activity found in DNA polymerase, there is evidence of that RNAP will halt at mismatched base-pairs and correct it.

The addition of ribonucleotides to the RNA transcript has a very similar mechanism to DNA polymerization - it is believed that these polymerases are evolutionarily related. Aspartyl (asp) resies in the RNAP will hold onto Mg2+ ions, which will, in turn, coordinate the phosphates of the ribonucleotides. The first Mg2+ will hold onto the α-phosphate of the NTP to be added. This allows the nucleophilic attack of the 3'OH from the RNA transcript, adding an additional NTP to the chain. The second Mg2+ will hold onto the pyrophosphate of the NTP. The overall reaction equation is:

(NMP)n + NTP --> (NMP)n+1 + PPi

Termination
Termination of RNA transcription can be rho-independent or rho-dependent:

Rho-independent transcription termination is the termination of transcription without the aid of the rho protein. Transcription of a palindromic region of DNA causes the formation of a hairpin structure from the RNA transcription looping and binding upon itself. This hairpin structure is often rich in G-C base-pairs, making it more stable than the DNA-RNA hybrid itself. As a result, the 8bp DNA-RNA hybrid in the transcription complex shifts to a 4bp hybrid. These last 4 base-pairs are weak A-U base-pairs, and the entire RNA transcript will fall off

2. 姚开泰的发表学术论文

在攻克癌症的征途上，这些年来，姚开泰在国际国内学术刊物上先后发表学术论文80多篇，成为国内乃至国际上都有影响的肿瘤学专家。美国中华医学基金会理事长Sawyer博士直言不讳地称赞：“他是我在中国找到地一位可以信赖地合作伙伴。”1990年，他们在国际上首次建立了EB病毒感染者的鼻咽癌细胞株，并对细胞株的EB病毒基因进行了研究，提出鼻咽癌的EB病毒可能有其特殊类型，为研究鼻咽癌何EB病毒的关系，提出了新的探索方向。
文章列表：
1、cDNA阵列和微阵列在鼻咽癌发生机制中的应用.pdf
2、中西医结合发展与现代科技交叉（续）——从基因组和肿瘤研究的进展瞻望中西医结合.pdf
3、克隆羊技术在肿瘤研究中的意义.pdf
4、瘤基因和抑瘤基因的表达和破坏在哺乳动物发育和肿瘤形成中的作用.pdf
5、瘤基因和抑瘤基因表达和破坏在哺乳类发育和肿瘤形成中的作用.pdf
6、瘤基因研究的某些进展.pdf
7、细胞周期调节分子机制与肿瘤发病.pdf
8、鼻咽癌产病因学研究的现状与瞻望.pdf
9、鼻咽癌研究的回顾与展望：（纪念湖南医科大学80周年校庆）.pdf
10、-.pdf
11、DesignandpreparationofEpstein-Barrvirusgenome-widecDNAprobes.pdf
12、Effects

13、Expression,lossofheterozygosity,.pdf
14、
-.
15、InvestigationofEpstein-.pdf
16、Isolationanddetectionoflabel-retainingcellsinanaso
pharyngealcarcinomacellline
17、Lentivirus-mediated
.pdf

3. PPR gene是什么功能是什么

PPR是由Small和
Peeters(2000)发现和命名的由35个氨基酸组成的序
列单元经串联重复排列而组成的一个基因家族.
在拟南芥(Arabidopsis thaliana)中,PPR基因家族
含有450个成员,尽管他们的大多数被预测和认为
定向于线粒体和叶绿体,也许在细胞器的基因表
达中具有作用,但他们的确切功能目前尚未知.

参考 http://cache..com/c?word=ppr%2Cgene&url=http%3A//www%2Eplant%2Dphysiology%2Ecom/pmbissue/2005/119%2Epdf&b=0&a=42&user=

4. 请各位生信大神看一下这个代码用到的生存分析方法是什么啊，虽然有代码，但小白码论文不知怎么描述

你好，请问这个代码你运行成功可吗？我运行后出现
错误: unexpected input in:
" ylab="Survival rate",
main=paste(gene,"(p", pValue ,")",sep=""）"
求解答！

5. 《加西亚·马尔克斯访谈录》pdf下载在线阅读，求百度网盘云资源

《加西亚·马尔克斯访谈录》（[哥伦比亚] 加西亚·马尔克斯）电子书网盘下载免费在线阅读

资源链接：

链接：https://pan..com/s/1q6a9OPKH8D6X7pC4aS1gBQ

书名：加西亚·马尔克斯访谈录

作者：[哥伦比亚] 加西亚·马尔克斯

译者：许志强

豆瓣评分：8.5

出版社：南京大学出版社

出版年份：2019-7

页数：424

内容简介：

【编辑推荐】

★马尔克斯访谈录中文版重磅面世，《百年孤独》标配读物，精选十一篇重要访谈，其中多篇访谈首度译成中文。

★十一堂诺奖大师文学课，展现马尔克斯二十多年创作脉络，绘制马尔克斯私人文学图谱。

听马尔克斯亲自揭秘他的作品：

他本人的心头好《枯枝败叶》，拒绝“严肃”诠释的《百年孤独》，包含他毕生经历的《霍乱时期的爱情》，结构周密如钟表发条的《一桩事先张扬的凶杀案》，“复仇”之作《迷宫中的将军》……

听马尔克斯与文学巨匠们隔空对话：

福克纳、卡夫卡、格雷厄姆•格林、卡波蒂、陀思妥耶夫斯基、博尔赫斯、海明威……

★十一场冒险之旅，跟讲故事大师马尔克斯飞升魔幻王国，深入鬼魅地狱，听他玩笑般讲述残酷诡异的故事，在拉美文学、历史、文化、政治等各领域探秘。

异域风情满溢的香蕉种植园，冰得烫手的鲷鱼，幽灵般消失的电车，像水一样淹死孩子的灯光，赤裸的玻利瓦尔，大开杀戒的独裁者……

★十一次面对面畅谈，搜寻打开马尔克斯世界大门的钥匙：爱与孤独。

★中文版由马尔克斯研究者许志强教授译出，并作长序导读。

★装帧由屡获“中国最美的书”殊荣的知名设计师周伟伟精心打造，封面甄选马尔克斯名言佳句，采用手揉纸，给人复古的体验、温柔的触感。

【内容简介】

加西亚•马尔克斯，《百年孤独》的作者，拉美文学的泰斗，作品畅销全球，所受关注度堪比电影明星。而他本人真正想扮演的角色只有一个，古老又神秘——讲故事的人。《加西亚•马尔克斯访谈录》精选了这位讲故事大师二十多年间接受的重要采访，清晰而系统地勾勒出他早期、中期乃至后期的创作脉络，更为了解和研究马尔克斯其人其事提供了珍贵的一手资料。这里汇集了马尔克斯的“即兴创作”，他尽情讲述着亦真亦幻的故事：他的童年、外祖父母、爱情；他的记者生涯、创作的艰辛与愉悦；他的卡夫卡、福克纳；他的加勒比根基、左翼立场、他与卡斯特罗的友谊；他对电影、音乐的看法……这部访谈录就像一个故事魔盒，记录了马尔克斯的真实声音、私密时刻、思想火花。魔幻现实在这里流淌，谈话的艺术在这里尽显。

作者简介：

【编者简介】

吉恩•贝尔-维亚达（ Gene H. Bell-Villada），美国威廉姆斯学院罗曼语系主任，着有《为艺术而艺术及文学生活：政治和市场如何帮助塑造唯美主义的思想和文化，1790—1990》（入围美国国家图书评论奖）、《海外美国人：在热带长大的外国佬》等。

【译者简介】

许志强，浙江大学世界文学和比较文学研究所教授、博导，着有《马孔多神话和魔幻现实主义》，译有《在西方的注视下》《水手比利•巴德》等。

6. 《DevOps实践指南》pdf下载在线阅读，求百度网盘云资源

《DevOps实践指南》（[美] Gene Kim）电子书网盘下载免费在线阅读

链接：https://pan..com/s/1zoFPqaNSjzZtFOLvV5tGbA

书名：DevOps实践指南

作者：[美] Gene Kim

译者：刘征

豆瓣评分：8.5

出版社：人民邮电出版社

出版年份：2018-4

页数：328

内容简介：

本书共分为6个部分：第一部分概述DevOps的历史和三个基本原则，即“三步工作法”；第二部分介绍开启DevOps转型的过程；第三到五部分深入探讨“三步工作法”的各个要素；第六部分关注如何将安全性和合规性正确集成到日常工作中。全书涵盖40余个DevOps案例，以谷歌、亚马逊、Facebook等全球知名企业和组织的实际调查结果为依据，展示如何通过现代化的运维管理提升管理效率，进而为企业赢得更大市场、创造更多利润。

作者简介：

作者简介：

Gene Kim

Tripwire创始人、前CTO，IT Revolution创始人，DevOps企业峰会主办人，畅销书《凤凰项目》合着者。

Jez Humble

DevOps Research and Assessment公司CTO，加州大学伯克利分校信息学院讲师；曾任ThoughtWorks首席顾问。《精益企业》和Jolt大奖图书《持续交付》的合着者。

Patrick Debois

DevOps之父，致力于通过在开发、项目管理和系统管理之中应用敏捷技术来填补项目和运维之间的鸿沟。

John Willis

Chain Bridge System创始人，曾任Docker公司布道师，现就职于SJ Technologies公司。

7. snaogene怎么裁剪峰图

三步。
首先，通过Open按钮打开ab1文件，接下来，点击Print按钮或File或者Print（快捷键Ctrl+P），打开打印对话框，Printer，Name选AdobePDF，1.接着点击Propeities按钮，2.设置打印属性。在布局选项卡将页面的方向改为横向。页面大小为A4即可（注意也可以选A3或更大，使目标序列片段不出现中间换行，以便后期截取目标片段），其他选项默认。回到Print窗口，点击OK按钮，选择导出PDF到桌面。

8. 哪里有<分子克隆实验指南 第3版>的电子版下载

记得在小木虫见过，中文，PDF图片格式的，上下册一共270多兆。
kcno兄，你的英文版多大，可能的话给我一份，谢了
[email protected]

9. 加密PDF的问题

使用一个软件，叫做Advanced PDF Password Recovery，去百都上搜索。。。不要找中文破解版的，因为大多数都是不能用或者未破解的，去找英文的破解版我现在就在用，很好用。（未破解版本的只能破解一页pdf）还有别找4。0版本的没，找不到破解的，去找1.0或2.0比较实际。

10. 《亚特兰蒂斯：基因战争》pdf下载在线阅读，求百度网盘云资源

《亚特兰蒂斯：基因战争》（[美] A.G.里德尔）电子书网盘下载免费在线阅读

资源链接：

链接：https://pan..com/s/19B-fwSrLDZole14ZJSYkNg

书名：亚特兰蒂斯：基因战争

作者：[美] A.G.里德尔

译者：邢立达

豆瓣评分：7.4

出版社：四川文艺出版社

出版年份：2015-10

页数：492

内容简介：

两千年来，一个古老的组织誓言保守人类起源的秘密，竭尽全力寻找一个自远古时代便已存在的宿敌，这个庞大的威胁具有消灭人类族群的邪恶力量，而所有一切物种本质谜团的线索，都指向失落的神话之城亚特兰蒂斯……

从事自闭症研究的遗传学家凯特，无意中发现智人突变转化的关键要素“亚特兰蒂斯”，竟也是1918年杀死全球五千万人超级传染病西班牙流感的始作俑者，却因此莫名遭到神秘组织伊麻里的追缉。

在地下反恐探员大卫的协助下，两人发现伊麻里掌握人类自古至今的历史进化秘密，与其背后的恐怖动机。原本互不信赖的凯特和大卫，必须在有限的时间内携手合作，一起解决这桩危及全世界的跨国阴谋，而亘古以来关于人类进化的最大谜底也即将揭

作者简介：

A.G.里德尔 A. G. Riddle

在美国的北卡罗来纳州的一个小镇长大，他曾花十年时间创办并运营一家互联网公司，后来才转行干起了自己最热爱的事情——写作。目前他已经成为亚马逊网站上科幻类图书第二畅销的作家，仅次于《冰与火之歌》的作者乔治·R·R·马丁（George R.R. Martin）。

目前与妻子居住在佛罗里达州的帕克兰，非常乐意收到读者对自己作品的反馈。

官网：http://www.agriddle.com/Atlantis-Gene

【译者简介】

邢立达，青年古生物学者，科普作家。1982年生于广东潮州，高中时期创建中国大陆首个恐龙网站。在加拿大阿尔伯塔大学取得古生物学硕士学位，师从着名古生物学家Philip J. Currie院士，目前在中国地质大学（北京）攻读博士学位，已发表科研论文百余篇。中国科普作家协会会员，出版过一批古生物科普书籍，并多次在CCTV各频道为公众介绍古生物知识。

何锐，科普写手，兼职译者。1976年生于江城，武汉大学博士，目前就职国企工程师。为杂志和网站撰写过若干科普和科幻文章。