Certain words of little intrinsic meaning appear too frequently to be useful in searching text. Information systems call these "stopwords"; you will not be able to search for the following words alone in MEDLINE, but they can be included within a phrase:
a about abs accordingly affect affected affecting affects after again against all almost already also although always among an and another any anyone apparently are arise as aside at away
be became because become becomes been before being between biol both briefly but by
came can cannot certain certainly chem copyright could
did different do does done due during
each effect effects either else enough especially et-al etc ever every
following for found from further
gave gets give given giving gone got
had has hardly have having here how however
if immediately importance important in into is it its itself
just
keep kept kg km knowledge
largely like
made mainly make many may mg might ml more most mostly much mug must
nearly necessarily neither next no none nor normally nos not noted now
obtain obtained of often on only or other ought our out overall owing
particularly past perhaps please poorly possible possibly potentially predominantly present previously primarily probably prompt promptly
said same seem seen several should show showed shown shows significantly similar similarly since slightly so some sometime somewhat soon specifically state states strongly substantially successfully such sufficiently
than that the their theirs them then there therefore these they this those though through throughout to too toward
under unless until up upon use used usefully usefulness using usually
various very
was were what when where whether which while who whose why widely will with within without would
