Starting on March 14th, PubMed Central (PMC) will be launching their new PMC website. The new interface will resemble the recently updated PubMed interface in 2020. This update is the first of ongoing updates to PMC to modernize it to provide a quicker more responsive website.

If you would like to explore the new interface before it goes live, check out PMC Labs.

For more information about the new website, you can check out the NCBI Insights blog post: Updated PMC Launching Soon!

When handling search results in PubMed a user may encounter a situation when some operations are limited to a certain number of citations. While some users may think that, in practice, they will never need to deal with a very large number of citations, such situations do occur.

Below are instances when PubMed users will encounter a limit to the number of citations (and Pubmed messages alerting to that):

• When browsing a lengthy list of search results or jumping to a page towards the end of a search results list (This site can display up to 10,000 results. Please see the User Guide for more information on navigating your search results.)
  
• When saving citations to file (Only the first 10,000 citations will be saved in your file.)
  
• When e-mailing your citations (Only the first 1,000 citations will be sent in your email. You will receive citations in multiple emails.)
  
• When adding citations to a Collection in My NCBI account: (Only the first 1,000 citations will be added to collection.)
  
• When sending citations to Clipboard (Only the first 500 items will be sent to clipboard.)

These problems can be addressed with the following options:

• Divide the result set into smaller chunks using the results timeline or custom date range filter.
• Adjust your search to retrieve fewer results.

Other databases, such as Embase, CINAHL, Scopus, Web of Science, have similar, but not exactly the same maximums of the number of citations allowed for certain operations.

The Medical Subject Headings (MeSH) thesaurus is a controlled and hierarchically-organized vocabulary produced by the National Library of Medicine (NLM). It is used for indexing, cataloging, and searching of biomedical and health-related information. MeSH includes the subject headings appearing in MEDLINE/PubMed, the NLM Catalog, and other NLM databases.

The NLM has released its annual list of MeSH changes, including highly anticipated NEW MeSH (Medical Subject Heading) terms for 2022!

The list covers a variety of changes and updates made to MeSH, including:

• Updated terms — these are MeSH terms that have been deleted, changed, or replaced to reflect more updated terminology
  • 24 terms were updated for 2022
• New terms — these are brand new MeSH terms added
  • 277 new MeSH Descriptors were added for 2022
  • 218 new Supplementary Concepts were added for 2022

New Covid-19-related MeSH Headings:

• 2019-nCoV Vaccine mRNA-1273
• BNT162 Vaccine
• Ad26COVS1
• ChAdOx1 nCoV-19
• Persistent Infection
• mRNA Vaccines
• Aerosolized Particles and Droplets
• Respiratory Aerosols and Droplets
• Adjuvants, Vaccine
• Nucleic Acid-Based Vaccines
• Vaccine Development
• Vaccine Efficacy
• Antigenic Drift and Shift
• Mass Gatherings
• Vaccination Hesitancy
• Thromboinflammation

New Cancer-related MeSH Headings:

• Immunomodulating Agents
• Interleukin Inhibitors
• MTOR Inhibitors
• Memory T Cells
• Memory B Cells
• Radiation Fibrosis Syndrome

Note: The MeSH Browser can be used to conduct in-depth searches of the vocabulary within MeSH, whereas the MeSH Database is a mapping tool within PubMed to quickly locate terms and add them to search strategies.