With the improvement of people’s living standards and rapid economic development, the incidence of diabetes mellitus (DM) is increasing in most parts of the world. DM presents an important potential threat to human health. In the present study, a model of diabetes in female mice was established, and fasting blood glucose was detected at week 4, after which the biochemical profiles were evaluated by histopathological analysis. The success rate of modeling in the normal control (NC) group and the low/ middle/high-dose streptozotocin (STZ) group were 0, 0, 25% and 60%, respectively. In the middle-dose and high-dose STZ groups, the liver index was increased significantly compared with the NC group (p<0.05). The blood biochemical indicators of total cholesterol and low density lipoprotein cholesterol in three STZ injection groups were as follows: alanine aminotransferase and aspartate transaminase in middle- and high-dose STZ groups, high-density lipoprotein cholesterol and serum creatinine in the high-dose STZ group, and blood urea nitrogen in the middle-dose STZ group were significantly increased (p<0.05). The level of total triglycerides was lower, obviously, in the high-dose STZ group than in the NC group (p<0.05). The mice showed marked steatosis, green-dyed fiber tissue coloring in varying degrees, and the contour of the hepatic lobules basically disappeared in STZ injection groups. The results suggest that to establish a diabetes model for female ICR mice, the optimum dose of STZ is 100 mg/kg.

The effects of Mg and Ca on sulfide modification of sulphur steel were studied to elucidate the difference between micromagnesium treatment and micro-calcium treatment for the inclusion of sulphur steel. The results show that the inclusions in the steel appeared with an oxide core of Al2O3 and MnS wrapped. After the addition of Mg, the core was changed to spinel, and the MnS coating was changed to Mn-Mg-S. After Ca was added, the core was changed to Ca-Al-O, and the MnS coating was changed to Mn-Ca-S. The Mg content was higher than Ca content in the sulfides of the steel. Therefore, Mg was more effective than Ca in terms of sulfide modification with the same content of Mg and Ca in steel, but the yielding rate of Mg was lower than that of Ca. The Mg content in the oxide core was higher than Mg of the coating of the inclusions in the steel treated with Mg or Mg-Ca. In contrast, the Ca content in the oxide core was lower than Ca of the coating of the inclusions in the steel treated with Ca or Mg-Ca. MnS formed and precipitated during the melt solidification process. The complex sulfide (Mg-Mn-S) was precipitated around MgO·Al2O3 in the Mg treated steel during the cooling process. CaS inclusion was precipitated on the CaO·Al2O3 inclusions in the liquid Ca-treated steel. Thus, CaS was formed first, whereas MnS was formed during the cooling process, followed by the formation of complex sulfide (CaS+MnS), which finally precipitated around CaO·Al2O3 in the Ca-treated steel.