Perhaps you should try some spelling variations:
survival procedures » surgical procedures (Expand search), surgical proceduresa (Expand search), surgical procedure (Expand search)
decreased survival » increased survival (Expand search), increases survival (Expand search), increase survival (Expand search)
toc decreased » to decreased (Expand search), the decreased (Expand search), not decreased (Expand search)
decrease toc » decrease of (Expand search), decrease the (Expand search), decreased to (Expand search)
decrease akt » decrease at (Expand search), decrease and (Expand search), decrease after (Expand search)
akt decrease » and decrease (Expand search), not decrease (Expand search), any decrease (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: "(( decrease toc decreased survival procedures ) OR ( decrease NOT decrease akt decrease ))~".
• Adding a wildcard symbol may retrieve word variants: (( decrease toc decreased survival procedures ) OR ( decrease NOT decrease akt decrease ))*.