Purpose　The aim is to develop a new method for the determination of the activity of hepatocyte growth factor (HGF). Met hods　 Rat hepatocytes were prep ared by collagenase perfusion and incubated at 5% CO2 incubator for 1.5 h. The n HGF was added into the culture medium and incubated at 5% CO2 incubator for 1.5 h. The cell viability was determined by MTT method.Results　～1 142 μg/ml improved the number of cell viability significantly （AHGF/Acontrol） ＞2.Conclusion　Th is new method was stable, time-saving and of good reappearance. It was adapted to the determination of HGF activity.

Purpose　The aim is to purify the peptide with antifu ngal activity from Aspergillus fumigatus culture fluid.Methods　 The pept ide was separated by ion exchange column chromatography and further purified by r everse phase HPLC,and the molecular weight was determined by tricine gel electro phoresis.Results　A kind of peptide(FIP) with antifungal activit y wa s separated. The molecular weight was about 8 000. The detection result by MTT method showed significant antifungal activity of the peptide to 5 kinds of fung i.Conclusion　 The study provided a reliable basis for developin g drug and antiseptic.

Purpose　The aim is to optimize the liquid culture conditions of dihydropyrimidinase producing strain Pseudomonas putida 9801. Methods　Plackett-Burman design and spherical symmetric desig n were used.Results　Optimum conditions for dihydropyrimidinas e formation of Pseudomonas putida 9801 were defined:yeast extract 2.39%, Glu cose 1.81%,Uracil 0.06%,K2HPO4*3H2O 0.2%, MgCl2*6H2O 0.05%and NaCl 0 .3%,when the strain was cultured at 32℃ for 10 h,about 3.02 units/ml of hydanto inase was obtained. This value was quite consistent with the theory value(2.91 u nits/ml).Conclusion　The liquid culture conditions of dihydrop yrimidinase producing strain were optimized.

Purpose　The aim is to study the transduction of m urine stem cell factor(SCF) into umbilical blood cells by LipofectinRMmediated and expression in them.Methods　Murine SCF cDNA encoding extra cellu lar domain was isolated using PCR from plasmid pRC/CMV(containing SCF gene), and then recombined into the expression vector pcDNA3,and transferred into enrichme nt cultural umbilical blood cells. Semi-quantitative RT-PCR was used to examin e the expression on mRNA level.And the effects of supernatant of transfected umb ilical blood cells were investigated alone or in coordinate with GM-CSF by colo ny formation test of human bone marrow cells in semisolid culture.Results 　SCF mRNA was expressed in transfected umbilical blood cells.The su pernat ant of transfected umbilical blood cells could increase the number of CFU-GM, s ynergizing with GM-CSF.Conclusion　The supernatant of umbil ical b lood cells transfected with vector containing mSCF gene can stimulate the colony formation of human bone marrow cells in combination with GM-CSF.

Purpose　The aim is to study the effects of solubl e chit osan on antitumor factors and NK cell activity in rats.Methods　The level of NO、TNF produced by peritoneal macrophages,IFN-γ production and NK ce ll activity of spleen was detected,after different concentrations of chitosan we re injected into the sarcoma 180 rats peritoneally.Results　Th e cont ents of NO、TNF、IFN-γ and NK cell activity in sacroma 180 rats were significa ntly higher in the chitosan groups than those in the control group (P＜0.01) .Conclusion　Chitosan could impove the immune function in rats .

Purpose　The aim is to increase stability and to s olve the problem of splitting of human serum γ-globulin products.Methods 　Fibrinolysin and profibrinolysin in the human serum γ-globulin p roducts were absorbed with L-lysine-Sepharose 4B.Results　Compared with the unabsorbed products, the splitting degree of the absorbed pr oducts decreased obviously.Conclusion　In manufacture of human serum γ-globulin products,absorbing fibrinolysin and profibrinolysin with L -lysine-Sepharose 4B may increase stability of the product.It was an effecti ve method to improve the quality of product.

Purpose　The determination method of rhG-CSF bio logical activity by NFS-60 cells was studied in accordance with WHO internation al standard for G-CSF.Methods　MTT method was adopted.R esults　The chomosone number of NFS-60 cell was 39, about 1×105 cells/ml to 1×107 cells/ml,the dying color showed gradient when the NFS-60 c ells was dyed by MTT,the method(4,4) was adopted in the determination of rhG-CS F biological activity,the average FL% of potency was 13.560% for single exprimen t,and the CV of inter-assay and intra-assay was lower than 10% and 10.109%,respectively.Conclusion　method(4,4) can be us ed in the determination of rhG-CSF biological activity,and the results can guid e the study and the manufacture of rhG-CSF effectively.

Purpose　The aim is to modify the pyrogenic pathol ogy mo del induced by injection of saccharomycetet water in rats,and to eliminate the t emperature decline period after injection of saccharomycete water sc.Metho ds　It was measured that the anus temperature of both two groups of rats (one group was injected of incubated saccharomycete water and the other inj ected unincubated saccharomycete water sc) 1,2,3,4,6,8 h after injection respect ively.Results　The anus temperature had no decline period and the temperature rose quickly in the group of injected with incubated saccharomyc ete water (in 34℃thermostasis water).There was significant difference(P＜0.05 or P＜0.01)between incubated group and unincubated group in temperature risin g by t-test.Conclusion　No temperature declining peri od was observed in the pyrogenic pathology model of rat, if those rats were trea ted with saccharomycete water which was incubated at 34℃for 0.5 h.

Purpose　The aim is to study the inhibiting effect s of nineteen amino acids to E.coli,St.aureus and B.Subtilis.Metho ds　The qualitative inhibition of nineteen amino acids on E.coli ,St.aureus and B.Subtilis was determined using filter papers treated by saturated amino acids placed on the bacteria medium dish.The quantitative inhibi ting effects of the amino acids which were proved to have inhibition to these th ree bacteria were determined in the bacteria LB medium with different concentrations of amin o acids.Results　It was indicated that cysteine was used to in hibit St.aureus.The best inhibiting time was 6 hours,and the optimum of concentrat ion was 0.625% in which the inhibiting rate was 92.62%.Conclusion　 Cysteine could inhibit St. aureus.

Purpose　The aim is to sulfonize Hunai polysaccharide fr om p leurotus tuber-rigium(Fr.)Sing. and to evaluate the antioxidative activities of the sulfated po lysaccharide (S-HNP).Methods　S-HNP was prepared by the reacti on of Hunai polysaccharide with chlorosulfonic acid-Pyridine. The antioxidative activities o f S-HNP were evaluated as follows: (1) the inhibition effects on Fe2+- Vc inducing the injury of rat liver mitochondria in vitro, (2) the protectiv e ef fect on CuSO4 -Phen-Vc-H2O2 inducing the damage of DNA, (3) the scaven ging effect on O*-2. Results　 S-HNP could protect mitochondria from lipid peroxidation induced by Fe2+-Vc, i ncluding the inhibitions of the increase of TBARS content, the swelling of mitoc hondria and the decrease of membrane fluidity, and protect DNA from the damage induced by CuSO4-Phen-Vc-H2O2， and scavenge O*-2 generated in the sel f-oxidation of pyrogallic acid. Conclusion　S-HNP exhibi ted marked antioxidative activities.