Question: What happens when the explode and major options are selected at the same time in a thesaurus?

Answer: For many thesaurus terms, there is the option to select either “explode” or “major” as discussed in previous articles.

However, the platform will also allow the selection of both “explode” and “major” at the same time



The command to do this type of search is:

Mjmesh.exact.explode(“Brain”)   or for Embase  Mjemb.exact.explode("Brain")

The platform will now carry out a mixture of searching the exploded terms and those assigned as major.

Hence, although this particular search is retrieving exploded terms (as illustrated above), and thus retrieving all the narrower terms associated with your search term – in this instance “Brain”, they are also being restricted to those terms that have had “major” associated to them by the indexers.

Thus, no terms (although exploded) will be retrieved unless  they have also been tagged with "major".


The benefit of this type of search is that you can retrieve all the exploded terms that are relevant to your search. However, still ensure that the major thrust of these records are in your topic area.   

Example records are:

Title: Effects of methylmercury on the pattern of NADPH diaphorase expression and astrocytic activation in the rat



Title: Multiple cerebral cysts are another possible feature of Jacobsen syndrome


Title: Immune cell puzzle COVID-19: how do SARS-CoV infections contribute to psychiatric diseases?