Learn to use Entrez the main search engine for the National Center for Biotechnology Information, NCBI. An understanding of the features of Entrez will improve all of your searches at the NCBI site--whether you seek genes, genomes, proteins, literature, or any of the other extensive data collections at NCBI. This is because Entrez provides a variety of tools for searching and retrieving that are common to many of the NCBI databases. Here we will review and highlight the general features of many of the most important Entrez tools.

You will learn:

  • how to globally search all Entrez databases at once
  • to perform basic, advanced, and Boolean searches effectively
  • to interpret the results lists and understand the displays
  • about some of the more advanced Entrez tools, such as Batch Entrez and Batch Citation Matcher
  • strategies to customize and save searches to re-run later, and output mechanisms for results


This tutorial is a part of the tutorial group Text-related tools. You might find the other tutorials in the group interesting:

PubMatrix: PubMatrix, an on-line tool for multiplex literature mining of the PubMed database.

iHOP: Information Hyperlinked Over Proteins text mining resource

STRING: known and predicted protein-protein interactions

Textpresso: Text-mining the biological literature

Gene Ontology: Gene Ontology controlled vocabularies in biology

XplorMed: eXploring Medline abstracts

GoMiner: Ascribe biological significance to large lists of genes by annotating them with their corresponding GO categories

Controlled Vocabularies: Standardized term lists that can enhance interactions with biological databases

DAVID: A tool that analyzes large lists of genes to provide biological meaning

PubMed: PubMed access to biomedical research literature


Miscellaneous : Broad overview training suites, or those not categorized by other existing collections, may be located here.

NCBI : This category includes resources maintained at the National Center for Biotechnology Information (NCBI).


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