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1.
During the last decade the number of seawater dimethylsulfide (DMS) concentration measurements has increased substantially. The importance this gas, emitted from the ocean to the atmosphere, may have in the cloud microphysics and hence in the Earth albedo and radiation budget, makes it necessary to accurately reproduce the global distribution. Recently, the monthly global DMS climatology has been updated taking advantage of the threefold increased size and better resolved distribution of the observations available in the DMS database. Here, the emerging patterns found with the previous versions of the database and climatology are explored with the updated versions. The statistical relationships between the seasonalities of DMS concentrations and other variables are re-examined. The positive correlation previously found between surface seawater DMS and the daily-averaged climatological solar radiation dose in the upper mixed layer of the open ocean is confirmed with both the updated DMS database and climatology. Re-examination of the latitudinal match-mismatch between the seasonalities of DMS and phytoplankton, represented by the chlorophyll a concentration, reveals that they are highly positively correlated in latitudes higher than 40°, but anti-correlated in the 20°–40° latitudinal bands of both hemispheres. Overall, these global emerging patterns provide key information to further understanding the factors that control the emission of volatile sulfur from the ocean. The large uncertainties associated with the methodologies used in global computations, however, call for caution in using these emerging patterns as predictive tools, and prompt to the design of time series and process-oriented studies aimed at testing the validity of the observed relationships.  相似文献   

2.
使用高通量方法学来检测基因表达情况在最近几年已非常普遍。微集芯片技术可同时定量成千上万的基因转录本。基因表达综合数据库(Gene Expression Omnibus 简称GEO)是目前最大的而且完全公开的高通量分子丰度数据库,主要储存基因表达数据。该数据库以一个灵活开放的设计理念,允许用户或科研人员来递呈,保存和检索多种不同类型的数据。本文综合描述一下近年来该数据库在基因表达数据挖掘中的应用,同时介绍一些通过使用用户友好网络界面能有效探索、查询和再现数百个实验和数百万个基因表达谱的工具,以方便数据进行挖掘和可视化。登录GEO公用数据库的网址为:http://www.ncbi.nlm.nih.gov/geo.  相似文献   

3.
Los Alamos Hepatitis C Immunology Database   总被引:3,自引:0,他引:3  
The Los Alamos Hepatitis C Virus (HCV) Sequence Database (http://hcv.lanl.gov or http://hcv-db.org) was officially launched in September 2003. The sister HCV Immunology Database was made public in September 2004. The HCV Immunology Database is based on the Human Immunodeficiency Virus (HIV) Immunology Database. The HCV Immunology Database contains a curated inventory of immunological epitopes in HCV and their interaction with the immune system, with associated retrieval and analysis tools. This article describes in detail the types of data and services that the new database offers, the tools provided and the database framework. The data and some of the HCV database tools are available for download for non-commercial use.  相似文献   

4.
A genetic association study is a complicated process that involves collecting phenotypic data, generating genotypic data, analyzing associations between genotypic and phenotypic data, and interpreting genetic biomarkers identified. SNPTrack is an integrated bioinformatics system developed by the US Food and Drug Administration (FDA) to support the review and analysis of pharmacogenetics data resulting from FDA research or submitted by sponsors. The system integrates data management, analysis, and interpretation in a single platform for genetic association studies. Specifically, it stores genotyping data and single-nucleotide polymorphism (SNP) annotations along with study design data in an Oracle database. It also integrates popular genetic analysis tools, such as PLINK and Haploview. SNPTrack provides genetic analysis capabilities and captures analysis results in its database as SNP lists that can be cross-linked for biological interpretation to gene/protein annotations, Gene Ontology, and pathway analysis data. With SNPTrack, users can do the entire stream of bioinformatics jobs for genetic association studies. SNPTrack is freely available to the public at http://www.fda.gov/ScienceResearch/BioinformaticsTools/SNPTrack/default.htm.  相似文献   

5.
With the availability of two-dimensional (2-D) gel electrophoresis databases that have many characterized proteins, it may be possible to compare a researcher’s gel images with those in relevant databases. This may lead to the putative identification of unknown protein spots in a researcher’s gel with those characterized in a given database, saving the researcher time and money by suggesting monoclonal antibodies to try in confirming these identifications. We have developed two tools to help with this comparison: (1) Flicker, http://www.lecb.ncifcrf.gov/flicker/, a Java applet program running in the researcher’s Web browser, to visually compare their gels against gels on the Internet; and (2) the 2DWG meta-database, http://www.lecb.ncifcrf.gov/2dwgDB/, a searchable database of locations of 2-D electrophoretic gel images found on the Internet. Recent additions to Flicker allow users to click on a protein spot in a gel that is linked to a federated 2D gel database, such as SWISS-2DPAGE, and have it retrieve a report from that Web database for that protein.  相似文献   

6.
Histone Sequence Database: new histone fold family members.   总被引:2,自引:0,他引:2       下载免费PDF全文
Searches of the major public protein databases with core and linker chicken and human histone sequences have resulted in the compilation of an annotated set of histone protein sequences. In addition, new database searches with two distinct motif search algorithms have identified several members of the histone fold family, including human DRAP1 and yeast CSE4. Database resources include information on conflicts between similar sequence entries in different source databases, multiple sequence alignments, links to the Entrez integrated information retrieval system, structures for histone and histone fold proteins, and the ability to visualize structural data through Cn3D. The database currently contains >1000 protein sequences, which are searchable by protein type, accession number, organism name, or any other free text appearing in the definition line of the entry. All sequences and alignments in this database are available through the World Wide Web at http://www.nhgri.nih. gov/DIR/GTB/HISTONES or http://www.ncbi.nlm.nih. gov/Baxevani/HISTONES  相似文献   

7.
Being poor man''s apple, banana has a wide popularity worldwide. It''s one of the important horticultural crops used irrespective of rich and poor alike. Manipur along with the other states of Northeast India harboured with plenty of wild and cultivated species of banana that are not fully explored. A data base named DEBDOM has been developed here describing the diversity of banana resources of Manipur and it comprises twenty eight genotypes of Musaceae. The database DEBDOM provides a sophisticated web base access to the details of the taxonomy, morphological characteristics, utility as well as sites of collection of Musa genotypes, and it would have contribute as a potential gene pool sources for the conservation, sustainability as well as for crop improvement in the future breeding programmes.

Availability

http://ibsd.gov.in/debdom/  相似文献   

8.
The Histone Sequence Database is an annotated and searchable collection of all available histone and histone fold sequences and structures. Particular emphasis has been placed on documenting conflicts between similar sequence entries from a number of source databases, conflicts that are not necessarily documented in the source databases themselves. New additions to the database include compilations of post-translational modifications for each of the core and linker histones, as well as genomic information in the form of map loci for the human histone gene complement, with the genetic loci linked to Online Mendelian Inheritance in Man (OMIM). The database is freely accessible through the World Wide Web at either http://genome.nhgri.nih.gov/histones/ or http://www.ncbi.nlm.nih. gov/Baxevani/HISTONES  相似文献   

9.
dbSNP: a database of single nucleotide polymorphisms   总被引:12,自引:0,他引:12       下载免费PDF全文
In response to a need for a general catalog of genome variation to address the large-scale sampling designs required by association studies, gene mapping and evolutionary biology, the National Cancer for Biotechnology Information (NCBI) has established the dbSNP database. Submissions to dbSNP will be integrated with other sources of information at NCBI such as GenBank, PubMed, LocusLink and the Human Genome Project data. The complete contents of dbSNP are available to the public at website: http://www.ncbi.nlm.nih.gov/SNP. Submitted SNPs can also be downloaded via anonymous FTP at ftp://ncbi.nlm.nih.gov/snp/  相似文献   

10.
The Los Alamos hepatitis C sequence database   总被引:6,自引:0,他引:6  
MOTIVATION: The hepatitis C virus (HCV) is a significant threat to public health worldwide. The virus is highly variable and evolves rapidly, making it an elusive target for the immune system and for vaccine and drug design. At present, some 30 000 HCV sequences have been published. A central website that provides annotated sequences and analysis tools will be helpful to HCV scientists worldwide. RESULTS: The HCV sequence database collects and annotates sequence data and provides them to the public via a website that contains a user-friendly search interface and a large number of sequence analysis tools, based on the model of the highly regarded Los Alamos HIV database. The HCV sequence database was officially launched in September 2003. Since then, its usage has steadily increased and is now at an average of approximately 280 visits per day from distinct IP addresses. AVAILABILITY: The HCV website can be accessed via http://hcv.lanl.gov and http://hcv-db.org.  相似文献   

11.
The Conserved Domain Database (CDD) is now indexed as a separate database within the Entrez system and linked to other Entrez databases such as MEDLINE(R). This allows users to search for domain types by name, for example, or to view the domain architecture of any protein in Entrez's sequence database. CDD can be accessed on the WorldWideWeb at http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=cdd. Users may also employ the CD-Search service to identify conserved domains in new sequences, at http://www.ncbi.nlm.nih.gov/Structure/cdd/wrpsb.cgi. CD-Search results, and pre-computed links from Entrez's protein database, are calculated using the RPS-BLAST algorithm and Position Specific Score Matrices (PSSMs) derived from CDD alignments. CD-Searches are also run by default for protein-protein queries submitted to BLAST(R) at http://www.ncbi.nlm.nih.gov/BLAST. CDD mirrors the publicly available domain alignment collections SMART and PFAM, and now also contains alignment models curated at NCBI. Structure information is used to identify the core substructure likely to be present in all family members, and to produce sequence alignments consistent with structure conservation. This alignment model allows NCBI curators to annotate 'columns' corresponding to functional sites conserved among family members.  相似文献   

12.
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15.
Context: Cluster of differentiation 40 (CD40), and its ligand CD40L, are major co-stimulatory molecules whose interactions are important in both cellular and humoral immunity, and has been suggested to play a role in the pathogenesis of acute coronary syndrome.

Objective: The aim of this study was to examine the association of CD40 polymorphisms (-1?C>T (rs1883832) and 945G>T (rs4810485)) and myocardial infarction (MI), and to test the association of CD40 gene haplotypes with MI in Tunisians.

Materials and methods: Three hundred and fifty MI patients and 301 apparently healthy controls were included in the study. The polymorphisms of CD40 were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Results: There were significant differences in the genotype and allele frequencies of CD40 gene -1?C>T (rs1883832) polymorphism between cases and controls. Stratifying according to gender, the association between the TT genotype and MI was statistically significant in males, only. Haplotype analysis revealed that the C-T and T-G haplotypes were associated with an increased risk of MI (p?=?0.012 and p?<?0.001, respectively).

Conclusions: Our work showed a significant association between the -1?C>T (rs1883832) polymorphism of the CD40 gene and MI in the Tunisians.  相似文献   


16.
The RESID Database is a comprehensive collection of annotations and structures for protein post-translational modifications including N-terminal, C-terminal and peptide chain cross-link modifications. The RESID Database includes systematic and frequently observed alternate names, Chemical Abstracts Service registry numbers, atomic formulas and weights, enzyme activities, taxonomic range, keywords, literature citations with database cross-references, structural diagrams and molecular models. The NRL-3D Sequence-Structure Database is derived from the three-dimensional structure of proteins deposited with the Research Collaboratory for Structural Bioinformatics Protein Data Bank. The NRL-3D Database includes standardized and frequently observed alternate names, sources, keywords, literature citations, experimental conditions and searchable sequences from model coordinates. These databases are freely accessible through the National Cancer Institute-Frederick Advanced Biomedical Computing Center at these web sites: http://www. ncifcrf.gov/RESID, http://www.ncifcrf.gov/NRL-3D; or at these National Biomedical Research Foundation Protein Information Resource web sites: http://pir.georgetown.edu/pirwww/dbinfo/resid .html, http://pir.georgetown.edu/pirwww/dbinfo/nrl3d .html  相似文献   

17.
The Thermodynamics of Enzyme-catalyzed Reactions Database (TECRDB) is a comprehensive collection of thermodynamic data on enzyme-catalyzed reactions. The data, which consist of apparent equilibrium constants and calorimetrically determined molar enthalpies of reaction, are the primary experimental results obtained from thermodynamic studies of biochemical reactions. The results from approximately 1000 published papers containing data on approximately 400 different enzyme-catalyzed reactions constitute the essential information in the database. The information is managed using Oracle and is available on the Web. AVAILABILITY: http://xpdb.nist.gov/enzyme_thermodynamics/  相似文献   

18.
19.
dbSNP: the NCBI database of genetic variation   总被引:1,自引:0,他引:1  
In response to a need for a general catalog of genome variation to address the large-scale sampling designs required by association studies, gene mapping and evolutionary biology, the National Center for Biotechnology Information (NCBI) has established the dbSNP database [S.T.Sherry, M.Ward and K. Sirotkin (1999) Genome Res., 9, 677-679]. Submissions to dbSNP will be integrated with other sources of information at NCBI such as GenBank, PubMed, LocusLink and the Human Genome Project data. The complete contents of dbSNP are available to the public at website: http://www.ncbi.nlm.nih.gov/SNP. The complete contents of dbSNP can also be downloaded in multiple formats via anonymous FTP at ftp://ncbi.nlm.nih.gov/snp/.  相似文献   

20.
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