Perhaps you should try some spelling variations:
significantly improved » significantly increased (Expand Search)
significantly longer » significantly lower (Expand Search), significantly larger (Expand Search), significantly higher (Expand Search)
improved decrease » improved urease (Expand Search), marked decrease (Expand Search)
longer decrease » larger decrease (Expand Search), linear decrease (Expand Search), largest decrease (Expand Search)

You may be able to get more results by adjusting your search query.

• Removing quotes may allow a broader search: (( significantly improved decrease ) OR ( significantly longer decrease )).