Perhaps you should try some spelling variations:
singal processing » singnal processing (Expand search), signal processing (Expand search), sandal processing (Expand search)
decrease lesions » disease lesions (Expand search), decreased response (Expand search), decrease adhesion (Expand search)
lesions decrease » response decrease (Expand search), lesions case (Expand search)
decrease singal » decrease fungal (Expand search), decrease renal (Expand search), decrease striatal (Expand search)
decrease and » decreases and (Expand search), decrease in (Expand search), decrease of (Expand search)
and decrease » and decreases (Expand search), and decreased (Expand search), and increase (Expand search)
decrease not » decrease of (Expand search), decrease akt (Expand search), decrease at (Expand search)
not decrease » to decrease (Expand search), not increase (Expand search), the decrease (Expand search)

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (( decrease AND decrease singal processing ) OR ( decrease lesions decrease NOT decrease ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( decrease and decrease singal processing ) OR ( decrease lesions decrease not decrease ))~".
• Adding a wildcard symbol may retrieve word variants: (( decrease and decrease singal processing ) OR ( decrease lesions decrease not decrease ))*.