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NCBI Databases

Literature

The World's largest repository of medical and scientific abstracts, full-text articles, books and reports

Bookshelf

Books and reports

MeSH

Ontology used for PubMed indexing

NLM Catalog

Books, journals and more in the NLM Collections

PubMed

Scientific and medical abstracts/citations

PubMed Central

Full-text journal articles

Genes

Gene sequences and annotations used as references for the study of orthologs structure, expression, and evolution

Gene

Collected information about gene loci

GEO DataSets

Functional genomics studies

GEO Profiles

Gene expression and molecular abundance profiles

HomoloGene

Homologous genes sets for selected organisms

PopSet

Sequence sets from phylogenetic and population studies

Proteins

Protein sequences, 3-D structures, and tools for the study of functional protein domains and active sites

Conserved Domains

Conserved protein domains

Identical Protein Groups

Protein sequences grouped by identity

Protein

Protein sequences

Protein Clusters

Sequence similarity-based protein clusters

Sparcle

Functional categorization of proteins by domain architecture

Structure

Experimentally-determined biomolecular structures

Genomes

Genome sequence assemblies, large-scale functional genomics data, and source biological samples

Assembly

Genome assembly information

BioCollections

Museum, herbaria, and other biorepository collections

BioProject

Biological projects providing data to NCBI

BioSample

Descriptions of biological source materials

Genome

Genome sequencing projects by organism

Nucleotide

DNA and RNA sequences

Probe

Sequence-based probes and primers

SRA

High-throughput sequence reads

Taxonomy

Taxonomic classification and nomenclature

Genetics

Heritable DNA variations, associations with human pathologies, and clinical diagnostics and treatments

ClinVar

Human variations of clinical significance

dbGaP

Genotype/phenotype interaction studies

dbSNP

Short genetic variations

dbVar

Genome structural variation studies

GTR

Genetic testing registry

MedGen

Medical genetics literature and links

OMIM

Online mendelian inheritance in man

Chemicals

Repository of chemical information, molecular pathways, and tools for bioactivity screening

BioSystems

Molecular pathways with links to genes, proteins and chemicals

PubChem BioAssay

Bioactivity screening studies

PubChem Compound

Chemical information with structures, information and links

PubChem Substance

Deposited substance and chemical information

BLAST

Basic Local Alignment Search Tool

BLAST is a tool for comparing an amino acid or nucleotide sequence to an entire sequence library, identifying regions of high sequence similarity.

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Video tutorial

VIDEO: NCBI Minute: Using organism (taxonomic) information with standalone BLAST

NCBI Minute: Using organism (taxonomic) information with standalone BLAST

Limiting a BLAST search to particular organism or taxonomic group is important for making BLAST searches efficient. This also produces results that are easier to ...

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Recent blog posts

today

Vector graphics downloads now available in NCBI genome browsers and sequence views

You can now download images in both PDF and Scaled Vector Graphics (SVG) formats from our Sequence Viewer and genome browsers such ...

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October 11, 2019

Visit the new ClinVar for easier variant interpretation!

The new ClinVar The new design for ClinVar pages is now our default view! Thank you for the feedback on the new ...

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October 9, 2019

New publication on AMRFinder, a tool that identifies resistance genes in pathogen genomes!

Read the recent publication (PMID: 31427293) on the AMRFinder, a tool that identifies antimicrobial resistance (AMR) genes in bacterial genome sequences using ...

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Recent videos

VIDEO: A New PubMed: Highlights for Information Professionals

A New PubMed: Highlights for Information Professionals

In this webinar for librarians and other information professionals Marie Collins from the National Library of Medicine demonstrates the new, modern PubMed. The video's key ...

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VIDEO: NCBI Minute: An Insider's Guide to the New My Bibliography

NCBI Minute: An Insider's Guide to the New My Bibliography

My Bibliography is a central place to save and share your citations. You can add PubMed citations, create them manually, or upload them from citation ...

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VIDEO: NCBI Minute: A Beginner's Guide to Genes and Sequences at NCBI

NCBI Minute: A Beginner's Guide to Genes and Sequences at NCBI

Interested in learning about genes and sequences but don't know how to begin? This webinar, intended for people with limited experience working with sequence information, ...

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