1. A nucleic acid which binds specifically to human factor VII/Vlla, said nucleic acid comprising at least 15 consecutive nucleotides of a polynucleotide having at least 40% nucleotide identity with the nucleic acid of formula (I) below: 5"-[SEQ ID No. 1]x-[SEQ ID No. X]-[SEQ ID No. 2]y-3" (I), in which: - "SEQ ID No. X" is chosen from the group consisting of the nucleic acids having at least 40 % nucleotide identity with at least one of the sequences SEQ ID No. 3 to SEQ ID No. 85 and SEQ ID No. 87 to SEQ ID No. 100, - "x" is an integer equal to 0 or 1, and - "y" is an integer equal to 0 or 1.