PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 28259933-10 2017 Furthermore, the combination of alfentanil and propofol treatments may produce synergistically antinociceptive effects by inhibiting the phosphorylation of ERK1/2 and decreasing the expression of c-fos in the spinal cord. Alfentanil 32-42 mitogen activated protein kinase 3 Rattus norvegicus 156-162