The phase equilibria of the Sn-Zn-Sb ternary system at 400 and 500°C were experimentally determined by electron probe microanalyzer, x-ray diffraction and differential scanning calorimetry. In this study, the ternary compound of (Zn,Sn)Sb is confirmed at 400 and 500°C. Additionally, a liquid phase region is found at 400°C with composition ranges of 9. at.% Sn, which becomes a prolongation of the main liquid as the temperature is raised to 500°C.

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Fresh pig heart tissues were homogenized and deli-pidized with cold acetone. The dry acetone powder was extracted with 0.45 M potassium acetate pH 4.5, the extract was fractionated with ammonium sulfate to 60% saturation, successively followed by four chromatography steps: chromatography on CM-Sepharose CL-6B; gel filtration on Sephadex G-100; Fibrin-Sepharose affinity chromatography and chromatography on DEAE-Sepharose CL-6B. The fibrin plate method was used for the tissue plasminogen activator (t-PA) activity determination. The porcine t-PA purified was proved to be homogeneous either by SDS gel electrophoresis or by high performance liguid chromatography with a molecular weight of 67,000. Using the human melanoma t-PA antigen and its rabbit antiserum, the double immunodiffusion and immu-noelectrophoretic tests demonstrated that the porcine t-PA possessed a cross-reaction with the human t-PA. During the purification procedure, it was found that the porcine t-PA was contaminated and reversibly bound with the cell fibronectin. The binding ability depends on salt concentration. They could be separated from each other on Sepharose G-100 gel filtration at high salt concentration, this reversible binding was further confirmed by mixing these two purified components monitored on high performance liquid chromatography. The fibronectin-bound t-PA retained its ability to activate plasminogen, indicating that these two proteins may exist in a form of complex in the in vivo tissue. Some monoclonal antibodies against the porcine t-PA were obtained, being used to screen what domain of the enzyme is responsible for binding the cell fibronectin.

We have purified factor VIII/von Willebrand factor complex from rabbit plasma and prepared a specific guinea-pig antiserum to the von Willebrand factor antigen. It was used for electroimmunodiffusion to determine von Willebrand factor level in rabbit plasma and for crossed immunoelectrophoresis to study its electrophoretic behavior. Rabbit von Willebrand factor had properties similar to human von Willebrand factor with respect to molecular weight, size heterogeneity, mobility and pattern in electroimmunodiffusion and crossed immunoelectrophoresis, and content in plasma. Plasma von Willebrand factor antigen levels in rabbits ranged between 46 and 147% of the standard plasma. Responses of plasma von Willebrand factor antigen and factor VIII to various bioactive agents were investigated with rabbits.When a small dose of adrenalin, a large dose of noradrenalin, and endotoxin were injected, plasma von Willebrand factor antigen level and ratio of von Willebrand factor antigen to factor VIII activity were elevated in different fashions during 6 hours after administration.The findings could deliver some information about the mechanism of changes in plasma von Willebrand factor observed in human diseases.