Abstract: Highly sensitive reagent for colorimetrically determining N-acetyl-.beta.-D-glucosaminidase (NAGase) activity by the continuous method, comprising sodio-3,3'-dichlorophenolsulfonphthaleinyl N-acetyl-.beta.-D-glucosaminide and a buffer, with which renal dysfunction can be diagnosed precisely, quickly, and easily.

Abstract: This invention provides anti-HBs monoclonal antibodies HBs 8Cl, HBs 18E9 and HBs 22B7, an anti-human IgM monoclonal antibody HIgM 10C9 and an anti-mumps virus monoclonal antibody MPV 10G3 capable of inhibiting nonspecific reaction in the reverse passive agglutination, hybridomas producing them, a method for sensitizing fixed hemocytes with anti-HBs monoclonal antibodies, a fixed hemocyte sensitized with them by the said method, a method for inhibiting the said nonspecific reaction by utilizing the said monoclonal antibodies and an assay for HBs antigen by appropriately combining the above.

Abstract: A method for stabilizing rubella HA antigen which comprises adjusting a rubella HA antigen suspension at pH 9.6 or higher, and more preferably, concurrently adding sodium azide thereto, or adding sodium azide alone at a concentration of 1 to 10% (w/v) thereto without the above adjustment of pH.

Abstract: A preservative solution for fixed avian erythrocytes for the viral hemagglutination test of this invention comprises purified water which may contain serum albumin, glycerol or dimethyl sulfoxide and, additionally, a preventive against the growth of bacteria as occasion demands. Fixed avian erythrocytes can stably be preserved in this solution. HA and HI test can precisely be performed by employing fixed avian erythrocytes suspended in this invention.