Reference Search Boolean Operators and Modifiers

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Use Boolean search operators and modifiers to target your search query and to find the results you need faster.

For example, a references search for turmeric immune cells returns over 11 million results; focusing the query by adding the and operator and quotation marks to search turmeric and "immune cells" returns 124 results.

Generic-AND.png

The and operator specifies two terms that must be included.

Examples:

  • flavor and extract
  • 3463-67-7 and 7664-41-7

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Generic-NOT.png

The not operator specifies a term that must be excluded.

Examples:

  • electrolysis not haptens  
  • 1,5-Di-2-naphthalenyl-3-pentanone not Dibenzylideneacetone

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Generic-OR.png

The or operator specifies that at least one expression or term in an expression is
required, more than one or all can be returned.

Examples:

  • ("flavor" or "extract") and ("turmeric" or "curcumin")
  • (flavor not dye) or extract
  • 13463-67-7 or 7664-41-7

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Generic-Bound_Phrase.png

Entering terms in quotation marks creates a bound phrase that specifies a side-by-side
relationship and an exact spelling (matches plurals, but excludes alternative spellings
and synonyms).

Examples:

  • cortisol metabolites and GnRH agonist
  • acetic anhydride not nitrogen nucleophiles

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Generic-Expression.png

Entering terms and operators in parentheses creates an expression that functions
as a single unit that interacts with other terms.

Examples:

  • (extract not flavor) and ("turmeric" or "curcumin")
  • ((turmeric or flavonoids) and immune cells) not inflammatory

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