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UNIT 1.3 Searching NCBI Databases Using Entrez

  1. Gretchen Gibney,
  2. Andreas D. Baxevanis

Published Online: 1 JUN 2011

DOI: 10.1002/0471250953.bi0103s34

Current Protocols in Bioinformatics

Current Protocols in Bioinformatics

How to Cite

Gibney, G. and Baxevanis, A. D. 2011. Searching NCBI Databases Using Entrez. Current Protocols in Bioinformatics. 34:1.3:1.3.1–1.3.25.

Author Information

  1. Bethesda, Maryland

Publication History

  1. Published Online: 1 JUN 2011
  2. Published Print: JUN 2011
Table 1.3.1. Entrez Boolean Search Statementsa,b
  1. a

    General syntax is as follows: search term [tag] [Boolean operator] search term [tag] [Boolean operator]

  2. b

    [Boolean operator]= AND, OR, or NOT. [tag] represents a tag chosen from the left column of the table above.

[ALL]All fields
[AU] or [AUTH]Author name
 O'Brien J [AUTH] yields all of O'Brien JA, O'Brien JB, etc.
 “O'Brien J” [AUTH] yields only O'Brien J
[ECNO]Enzyme Commission or Chemical Abstract Service numbers
[FKEY]Feature key (nucleotide only)
[GENE]Gene name
[ISS]Issue of journal
[JOUR]Journal title, official abbreviation, or ISSN number
 Journal of Biological Chemistry
 J Biol Chem
[MAJR]MeSH Major Topic
 One of the major topics discussed in the article
[MDAT]Date of most recent modification to Entrez
[MOLWT]Molecular weight of a protein, in Daltons
[MH]MeSH Terms
 Controlled vocabulary of biomedical terms (subject)
[PS]Personal name as subject
 Use when name is subject of article, e.g., Varmus H [PS]
[PDAT]Publication date
[PROT]Protein name (not available in Structure database)
[PT]Publication type
 Clinical Trial
 Technical Publication
 Used to modify MeSH terms
 hypertension [MH] AND toxicity [SH]
[SUBS]Substance name
 Name of chemical discussed in article
[WORD]Text words
 All words and numbers in the title and abstract, MeSH terms, subheadings, chemical substance names, personal name as subject, and MEDLINE secondary sources
[TITL]Title word
 Only words in the definition line (not available in Structure database)
[UID]Unique Identifiers (PMID/MEDLINE numbers)
[VOL]Volume of journal