Perhaps you should try some spelling variations:
significantly improved » significantly increased (Expand Search)
significantly altered » significantly affected (Expand Search), significantly elevated (Expand Search), significantly lower (Expand Search)
improved decrease » improved urease (Expand Search), marked decrease (Expand Search)
altered decrease » altered release (Expand Search), observed decrease (Expand Search), teer 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 altered decrease )).