The establishment of a serum-free culture medium (SFM) for SSV-NIH3T3 cells is reported in this paper. In this medium DMEM/Ham's F12 is the fundamental element in basal medium, insulin and undefatty bovine serum albumin are key elements among the supplements. In this SFM SSV-NIH3T3 cells grow well, they keep the ability of secreting platelet-derived growth factor-like material into culture medium and causing tumor growth in nude mice.

In this study the nutritive value of 4 kinds of weaning foods containing soyflour were measured by chemical and animals experiments. The 4 experimental weaning foods were:1.This formula was developed by the Institute of Health collaborating the First Food Factory of Beijing. It was produced by the Factory and the trade name is "Baobao Le" The soybean was processed by the infra-red light.2.This formula was recommended by UNICEF (Formula No. 5). Soybean flour was treatded with the extruded method.3.This formula was the same as No. 2 (UNICEF Formula No. 5). In which the soybean was wet-heat treated. No. 2 and 3 samples were produced by Wu Xi Light Industry College.4.This formula was developed by the Institute of Shanghai Food Industry as formula D. Puffed soybean flour was used.The 2 control foods were:5.This formula was based on formula "5410". The sample was made by the First Food Factory of Beijing (trade name, "Nutritive Baby Powder").6.Infant Milk Powder, produced by the Child Milk Factory of Shuang Cheng Xian, Hei Long Jiang Province, cow's milk powder was used as the main source of protein. The protein content of the products were:No. 1 and 4, 19.0%, equal to the protein requirement for weaning foods; No.2 and 3, 15.8%, lower than No.1 and 4; Infant Milk Powder, 15.1%; Nutritive Baby Powder, 17.0%.From the results of the animal experiment on weaning rats with respect to growth, after 9 weeks of feeding, the average body weight of control group 5 and 6 increased by 185.8 and 180.5g respectively, which were significantly higher than 146.7 and 150.4g of the experimental groups No. 1 and 4. While the increased body weight of No. 1 and 4 were higher than group 2 and 3 (79.8g and 113.1g respectively). The increase of body lengths were of the same order of the 6 groups as that in body weight.Blood hemoglobin values were all normal (control groups 13.4 and 13.9g per 100 ml; experimental groups 13.9, 14.2, 13.0 and 13.0g).The weight of pancreas in the 4 experimental groups were all normal. It showed that the activity of trypsin inhibitor had been destroyed. Weights of thyroid of the rats were all within the normal range except group 1,2,3, which were a little bit heavier. Potassium iodide was.added into formula 1,2 and 3, to prevent hyperthyroidism but since potassium iodide is easily to evaporate, so it would be perferable to use potassium iodate instead.The above results indicated that the growth promoting effect of the 4 weaning foods is lower than the two baby powder, but they are good weaning foods for baby after six months. "Baobao Le" and formula No 6 are much better.