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1.
以DNA微阵列、二维电泳、二维高压液相色谱和质谱等技术为代表的转录组和蛋白质组高通 量实验技术,能够产生海量的基因或蛋白质数据,对这些基因或蛋白质的注释是对相关数据 进 行后期处理的基础和必要条件.海量数据的注释人工难以完成,而目前基因和蛋白质的批量 注释网站给出的注释又往往不够全面.在比较常用基因和蛋白质的批量注释网站的基础上, 本工作研发了基因和蛋白质的批量注释系统UBROAD(Unified Batch Retriever of Annotati on Data),该系统整合了NCBI、Swiss Prot、BIND、enzyme -expasy、gene2accession 和gene2Unig ene 6个有关基因和蛋白质的数据源;支持Uniprot/trEMBL AC、 Uniprot Entryname、Genb ank Protein Accession Number、Genbank mRNA gi、Genbank mRNA Accession Number、 G ene name、 Gene ID和Unigene ID 8种登录号混合查询;含有各种登录号以及基 因或蛋白质的基本信息、功能分类、相互作用共38项注释项供选择;提供微软电子表格形式 的注释结果.可以通过访问网页http://www.bioscience.org.cn/ubroad免费使用该系统.  相似文献   

2.
蜡状芽胞杆菌ATCC 10987对于细菌比较基因组学的研究有重要意义.但其染色体中基因的数目被RefSeq注释为5 603个,这个注释是有疑问的.本文采用Zcurve和Glimmer程序联合打分的方法来识别其蛋白质编码基因.为保证预测结果的可靠性,对联合判别附加预测的基因使用了BLAST方法进行数据库同源性搜索.结果,蜡状芽胞杆菌ATCC 10987基因组中的蛋白质编码基因的数目被重新确定为5 180个.这个数目明显低于原始注释的数目,并且一些指标表明新的注释更为可信.这些相对正确的基因集合为该细菌亲缘物种的深入研究提供了基础.  相似文献   

3.
以成年雌性淞江鲈肝脏组织为材料,用TRIzol Reagent试剂提取总RNA.以总RNA为模板,先用逆转录酶合成cDNA第一链,再通过LD-PCR合成cDNA第二链,所得双链DNA分子用SfiⅠ酶切处理后,连接到同样经SfiⅠ酶切处理的改良pUC19载体上,获得重组质粒.将重组质粒导入大肠杆菌DH5α感受态细胞中,建成质粒cDNA文库.经鉴定,该文库库容为1.5×106,重组率为94.5%,平均插入片段长度为1.1kb,插入片段大小分布为0.5~2.0kb.从文库中随机挑选2 200个克隆进行5’端单向测序,剔除不合格序列后,得2 002条高质量表达序列标签(Expressed Sequence Tag,EST)序列,提交dbEST数据库.经筛选,从这些EST序列中共发现471个基因,分别对其进行了KOG功能分类预测(216个蛋白被注释上21种KOG分类)、KEGG注释(186个基因注释上175个KO,139个基因注释上195个pathway)和GO功能分类注释(312个蛋白被注释上GO分类).  相似文献   

4.
提出一种蛋白质亚细胞定位预测方法.该方法以位置特异性得分矩阵和基因本体抽取对应特征,结合支持向量机构建多标签分类模型.充分考虑了蛋白质进化信息对其亚细胞定位的影响,并基于文本分类中涉及到的卡方检验的对数变换思想,构建基因本体注释信息的加权系数对其进行加权处理,从而提高预测的准确率.采用支持向量机作为基分类器构建多标签分类模型,进一步提高预测的准确率.通过在目前该领域两个常用的真实数据集上进行的一系列测试结果表明,该方法能有效提高蛋白质亚细胞定位预测的准确率.  相似文献   

5.
通过同源映射的方法,利用6个模式物种的蛋白质相互作用数据预测水稻的蛋白质相互作用网络.预测到水稻中有4483个蛋白质参与了24942个蛋白质相互作用.通过GO注释,结构域相互作用,基因共表达等3个证据评估预测网络的质量,并对网络进行了拓扑属性分析.结果表明水稻的蛋白质相互作用网络符合scale-free属性.通过对网络中功能模块的分析,可以预测蛋白质的功能和亚细胞定位信息.  相似文献   

6.
针对用户在搜索结果列表中寻找所需信息困难的问题,在分析了Web搜索结果的特点的基础上,提出了一种结合K-Means的层次化方法对搜索结果进行聚类,并通过向用户提供查询结果的类别标签分类显示结果,从而大大提高可浏览性.同时,在该方法的基础上设计并实现了一个搜索结果聚类原型系统,实验结果表明新方法是可行的.  相似文献   

7.
本实验旨在对绵羊肌肉转录组进行组装分析,以丰富绵羊的基因组并为进一步对绵羊的相关基因的分子遗传学研究奠定基础。选取Illumina Hiseq 2000测序平台对杜泊羊和小尾寒羊的骨骼肌转录组文库进行了高通量测序,并对测序数据进行从头组装分析。结果表明:两个测序文库共得到103058824个长为2×90bp的高质量的测序序列,经从头组装共产生了145524个unigenes。两个文库间有5718个unigenes差异表达,经GO注释分析后发现它们主要分布在细胞、细胞过程和结合条目中。将两个文库的unigenes进一步组装得到70348个平均长为863bp的all-unigenes,其中35201个被注释到Nr数据库,12219个被注释到COG数据库,并与KEGG数据库中的258个功能通路中的蛋白质和氨基酸新陈代谢通路密切相关。  相似文献   

8.
为了获得花斑裸鲤丰富的转录组信息和功能基因,应用Illumina Hi SeqTM2500高通量测序技术对花斑裸鲤肝胰脏、肌肉、脑、和肾混合组织转录组进行测序,获得162 235条转录本,进一步拼接得到110 231条单基因序列(unigene),平均长度745 bp。利用生物信息学方法对所有unigenes与美国国立生物技术信息中心(NCBI)的非冗余蛋白质数据库(Nr)进行相似搜索(E-value≤10-5),结果共有34 532个unigenes(31.32%)与数据库中的已知基因同源。此外,GO功能注释将unigene分为生物过程、细胞组分和分子功能3大类56分支,依据KOG功能注释可分为26个功能组分,依据KEGG代谢通路分析可以分成5大类267小类。通过转录组测序数据及功能注释,进一步了解了更多花斑裸鲤的生物学特性、基因的分子功能、参与的生物过程、所处的代谢途径和信号通路。同时,获得了79条与天然免疫相关的同源序列。  相似文献   

9.
目的针对百度和360等通用搜索引擎搜索旅游信息速度不够快、不准确和分类不明确的缺点,设计和实现了一个面向游客查找旅游信息的网络爬虫,给出了该网络爬虫所采用的自适应垂直搜索算法.方法基于领域本体,建立相应的知识模型和查询模型,并在基于知识模型和查询模型的基础上设计一个综合查询方法,拓展所需要查询的信息.结果设计了一种自适应旅游信息垂直搜索算法和相应的网络爬虫,并用软件实现了该网络爬虫.用设计的网络爬虫对辽宁省公园、辽宁省儿童公园和辽宁省森林公园进行的搜索,采用自适应算法搜索时,Per(用户搜索百分比)为92%,采用基于网页内容的URL选取算法搜索时,Per为82%.对吉林省旅游景点、吉林省公园和吉林省森林公园进行的搜索,采用自适应算法搜索时,Per为91%,采用基于网页内容的URL选取算法搜索时,Per为80%.与经典的搜索方法相比,搜索结果更准确,分类效果更好.结论所设计的垂直搜索算法对旅游信息的搜索是有效的,在查询的准确率和信息的分类上都有一定的提高和改进.  相似文献   

10.
选择性剪接是真核生物基因调控的基本调节机制之一,与各种类型的生理和病理活动相关.癌症相关基因的不正常剪接可能与多种癌症的发生发展有关.作为选择性剪接进化的主体,选择性剪接外显子展示了其在不同物种中多样的进化功能.本文系统整理了2 989个癌症相关基因的各项功能,通过比较基因组学的分析方法总结了癌症相关基因的选择性剪接外显子的功能和进化关系,建立了癌症相关基因选择性剪接进化数据库(ASeeDB数据库).ASeeDB包含癌症相关基因外显子区域的进化保守性、结构域预测、Ka/Ks值、以及基因、转录本、外显子区域3个层次的表达量统计等信息,结合这些信息用户可以方便的检索有研究意义的基因或者外显子.外显子区域蛋白质结构域的预测可以帮助了解其可能的功能,而外显子是否存在选择性剪接又可以推及包含该外显子的转录本是否具有相似的功能以及推测剪接是否会对蛋白质功能发生影响.数据库提供的物种间的序列比对可以帮助用户发现没有注释的外显子区域或者是保留的失去功能的外显子.相比于基因层面的Ka/Ks,数据库提供的外显子层面的Ka/Ks对于发现适应性进化事件具有更高的敏感性,可以更加方便地预示基因中未知功能的区域.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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