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LinkOut Help [Internet]. Bethesda (MD): National Center for Biotechnology Information (US); 2006-.

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LinkOut Help [Internet].

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Welcome to LinkOut

Created: ; Last Update: November 21, 2019.

Estimated reading time: 2 minutes

LinkOut is a service that allows you to link directly from PubMed and other NCBI databases to a wide range of information and services extending beyond the NCBI systems. LinkOut aims to facilitate access to relevant online resources to extend, clarify, and supplement information found in NCBI databases.

LinkOut provides access to a variety of relevant online resources, including full-text publications, biological databases, consumer health information, and research tools, directly from PubMed and other NCBI databases.

All links are specially assigned to specific citations and database records. When accessing a link through LinkOut, no additional searching will be necessary to access the relevant resource that has been linked to the citation or database record.

Links are supplied by LinkOut resource providers. LinkOut resource providers are responsible for supplying and maintaining their links. We work with the providers to minimize errors.

Information about LinkOut is also available in the LinkOut website.

Examples of LinkOut Resources

Click the links below to see examples of LinkOut resources. See Databases Available for Linking for a complete list of databases that may have LinkOut resources.

From the PubMed database:

Online full text – Links to online full text from publishers and from PubMed Central appear in PubMed’s Abstract and Citation displays.

Consumer health information – This example displays articles with links to the MedlinePlus consumer health resource. Expand “LinkOut – more resources” to see the MedlinePlus links under the ‘Medical’ category.

Commentaries on articles – Links to commentaries or discussion to extend/continue the topic discussed in the article cited in a PubMed citation. Commentaries appear under “Other Literature Sources.”

Supplemental Materials – This example displays citations with links to the Dryad Digital Repository. Expand “LinkOut – more resources” to see the links under “Other Literature Sources.” See the Dryad link in this citation: https://0-www-ncbi-nlm-nih-gov.brum.beds.ac.uk/pubmed/26354940.

Another example of links to supplemental materials is the following link provided by SciCrunch, which aggregates related records from multiple databases:


From the Nucleotide and Protein databases:

Genome databases, for example, FlyBase

Links to suppliers of research materials – PlasmID Repository at Harvard Medical School

Research tools - UCSC Genome Browser

From the Taxonomy database:

Links from the Taxonomy database provide a variety of information about the entry term, for example:

Resources related to Ginkgo biloba, including toxicity, medicinal value, and a picture of the plant

Biological information about Amphibia species in AmphibiaWeb. To retrieve all Taxonomy records for which AmphibiaWeb has provided links, use the filter loprovamphiweb[sb].

Other links in the Taxonomy records include images of plants, animals, fossils, people, and landscapes from CalPhotos.

From the Gene database:

The Gene database contains many links that provide supplementary information to the Gene record. For example:

The Weizmann Institute of Science GeneCards and MalaCards databases. To retrieve all Gene records for which the Weizmann Institute has provided links, use the filter loprovweizmanninst[sb].

Genenetwork. To retrieve all Gene records for which the Genenetwork has provided links, use the filter loprovgenenetwork[sb].

From the BioProject database:

Genomes Online Database (GOLD). To retrieve all BioProject records for which GOLD has provided links, use the filter loprovgold[sb].

Additional Assistance

Send comments and suggestions about LinkOut and report broken links to vog.hin.mln.ibcn@tuoknil.


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