(1) So the two ends of the tetramer are indistinguishable.

(2) This invention relates to a tetramer combined with SARS antigen peptide and its preparation and use.

(3) An MHC class I tetramer was composed of 4 MHC class I complexes and a fluorescently labeled streptavidin molecule.

(4) Cultured tet + B cells produced antibodies specific for epitopes of the tetramer antigen.

(5) The results indicated that novel catalyst system had high activity for propylene oligomerization. The products were mainly tetramer and pentamer.

(6) The results show that the zirconium atom exist as tetramer in sol and the nano zirconia is the product of deprotonation and polymerization of the tetramer.

(7) The results showed that the obtained product is a mixture mainly composed of dimer, trimer, tetramer and pentamer .