Stop codons

Stop codon is a nucleotide triplet within messenger RNA that signals a termination of translation.

Unleash power of MeSH to search PubMed

This little application will not only help you to find results closely matching your query but also to better understand inner workings of PubMed.

Search PubMed:

"Stop codons"

Configure:

Headings

Search words are contained in title, abstract, or any heading
Search words are contained only in major headings
Search words are contained in any heading

Subheadings

Classify search results by subheadings

How many articles to analyze

1000 or less is allowed for an initial request at this time

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Definitions

PubMed is a service of the U.S. National Library of Medicine that includes over 18 million citations from MEDLINE and other life science journals for biomedical articles back to 1948. PubMed includes links to full text articles and other related resources.

MeSH (stands for Medical Subject Headings) is the U.S. National Library of Medicine's controlled vocabulary used for indexing articles for MEDLINE/PubMed. MeSH terminology provides a consistent way to retrieve information that may use different terminology for the same concepts.

Quick giude to scroring algorithm used here

• Only articles that were indexed for MEDLINE are scored
• Lowest score equals 1
• If search words appear in "DescriptorName" of "MeSHHeading" 10 is added to the initial score for each word
• Search words are counted in the abstract of the article, number of their appearances is multiplied by 5 and added to the score
• If search words are found in the title of the article, 20 is added to the score
• If "MeSHHeading" was marked as Major 20 is added to the score
• Finally, if one of words coincides with Major "Subheading" ("QualifierName") the score is multiplied by 3

Example

• Go to PubMed database
• Query the database for "Lyme children" and scroll to articles that marked as [PubMed - indexed for MEDLINE] - these articles are scored by the algorithm
• Locate article with PMID 18564251: PMID: 18564251
• On the tool bar locate "Display" menu pull-down and choose "XML"
• Explore structure of the resultant XML document and locate one of "MeSHHeading" elements
• For exmaple in the following exerpt

            <MeshHeading>
                  <DescriptorName MajorTopicYN="N">Lyme Disease</DescriptorName>
                  <QualifierName MajorTopicYN="N">diagnosis</QualifierName>
                  <QualifierName MajorTopicYN="N">drug therapy</QualifierName>
                  <QualifierName MajorTopicYN="Y">transmission</QualifierName>
          </MeshHeading>
          

  "DescriptorName" is what is called "Heading" in the MeSH database. It adds 10 to the overall score of this article, however, because this heading is not Major the article does not get additional scores. "QualifierName" is what is called "Subheading" in the MeSH database.