Perhaps you should try some spelling variations:
"50 ng decrease" » "50 _ decrease" (Expand Search), "10 ng decrease" (Expand Search), "50 μg decrease" (Expand Search), "50 _g decrease" (Expand Search), "50 ig decrease" (Expand Search)
"_ wt decrease" » "_ _ decrease" (Expand Search)
"50 n decrease" » "50 _ decrease" (Expand Search), "50 _ decreased" (Expand Search), "50 _ decreases" (Expand Search), "50 i decrease" (Expand Search)
"_ a decrease" » "_ _ decrease" (Expand Search), "_ _ decreased" (Expand Search), "_ _ decreases" (Expand Search)

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"50 n decrease\") OR (\"50 ng decrease\"))) OR (((\"_ wt decrease\") OR (\"_ a decrease\"))))~".
• Removing quotes may allow a broader search: (((( 50 n decrease ) OR ( 50 ng decrease ))) OR ((( _ wt decrease ) OR ( _ a decrease ))))~.
• Adding a wildcard symbol may retrieve word variants: (((("50 n decrease") OR ("50 ng decrease"))) OR ((("_ wt decrease") OR ("_ a decrease"))))*.