Strengthening basic animal operation training is not only beneficial to improving students’ practice ability so as to help students lay a solid foundation for clinic treatment and research work.,but also plays an important role in physiological scientific experiment teaching,which is essential for improving teaching quality. We have an active investigation in this aspect.

AIM: To observe the changes of bone in female Sprague Dawley rats aged 4.5 and 7.5 months. METHODS: Forty 4 month old virgin female Sprague Dawley rats were randomly divided into 4.5 month group and 7.5 month group. Bone histomorphometric analysis of the proximal tibial metaphysis (PTM), tibial shaft (Tx) and the fifth lumbar vertebral body (LV5) was performed in undecalcified sections. RESULTS: There was no significant change in bone volume of PTM, LV5 and Tx between 4.5 and 7.5 months of age. However, the bone formation parameters (%L.Pm, MAR, BFR/TV, BFR/BV, BFR/BS) of LV5 and Tx fall rapidly between 4.5 and 7.5 months of age. CONCLUSION: There is no significant change in cancellous and cortical bone mass, but the bone formation of LV5 and Tx decreases in female Sprague Dawley rats aged from 4.5 to 7.5 months.

AIM: To study the effects of Ginseng fiber on hepatic fibrosis induced by CCl 4 in mice. METHODS: Forty PCR Mice were randomly divided into 4 the control group, the NS group, the colchicine group and the Ginseng fiber groups. Rats in control group were treated by daily oral gavage with vehicle. Rats in other three groups were given SC injection of 40% CCl 4 10 ml?kg -1 and treated by either daily oral gavage with vehicle, or colchicine at 0.1 ml?kg -1, or Ginseng fiber at 10 g?kg -1 for 42 d. The liver injury indexes were measured. RESULTS: Compared with control group, the serum enzymes of alanine aminotransferase (ALT), aspartic acid aminotransferase(AST) were markedly increased but serum albumin (Alb) and A/G were decreased distinctly in CCl 4 group whose liver slides also showed typical liver cirrhosis. Ginseng fiber markedly prevented CCl 4-induced increases in liver weight, serum ALT and TP. Ginseng fiber lightened the hepatic pathological necrosis resulting from CCl 4. The preventive effect of Ginseng fiber was identical to that of colchicine. CONCLUSION: Ginseng fiber can prevent hepatic fibrosis induced by CCl 4 in mice.

AIM: To study the relationship between hepatic fibrosis and osteoporosis, and observe the preventive effects of ginseng fiber on bone loss. METHODS: Forty PCR mice were randomly divided into 4 groups. The mice in control group were treated by daily oral gavage with vehicle. The mice in other three groups were given SC injection of 40% CCl_4 10 ml?kg -1 and treated by either daily oral gavage with vehicle, colchicine, or ginsen hair for 42 d. The liver injury indexes were measured and the mineral elements and hydroxyproline of femur were determined. RESULTS: Compared with the control group, the serum enzyme activity of alanine aminotransferase (ALT), aspartic acid aminotransferase (AST) markedly increased and serum albumin (Alb) and A/G distinctly decreased in CCl_4 group whose liver slides also showed typical liver cirrhosis. The dried weight of femur markedly reduced and the bone calcium content and bone hydroxyproline content significantly decreased in CCl_4 group. Bone copper and bone magnesium increased in CCl_4 group. Ginseng fiber markedly decreased the serum enzyme activity of ALT and increased the bone calcium content and bone hydroxyproline content. The preventive effects of ginseng fiber was similar to that of colchicine. CONCLUSION: The bone mass is lost in mice with chronic hepatic injury induced by CCl_4. Ginseng fiber can prevent bone loss and hepatic fibrosis induced by CCl_4 in mice.

AIM: To study the factors that affect bone volume in ovariectomized rats. METHODS: The bone volume and factors were analyzed by the grey system theory method in ovariectomized rats. RESULTS: Serum estradiol was the most important factor for the bone volume, followed by the bone contents of calcium, phosphorus and magnesium. Serum calcium, phosphorus and the bone contents of hydroxyproline were the less important factors for the bone volume. CONCLUSION: Serum estradiol and bone contents of calcium are the most important factors that affect bone volume in ovariectomized rats.KEY WOLDS grey correlative analysis; bone volume; factors; ovariectomized rats; osteoporosis

Objective To analyze the characteristics and causes of an occupational acute carbon monoxide poisoning incident caused by a nitrogen generator malfunction. Methods The workers and the workshop from an electronic component manufacturing company in Guangzhou City, which had an occupational acute carbon monoxide poisoning incident, were selected as the research subjects using the retrospective investigation method. Relevant data of worksite survey of occupational health, clinical records of poisoning patients, and occupational disease diagnosis data were collected for analysis. Results A total of 15 workers who experienced discomfort in this incident, were from the final inspection workshop using high-purity nitrogen (purity of 99.999%). The short-term exposure concentration of carbon monoxide in the workplace air at three oven operating posts using high-purity nitrogen was 64.1, 581.0, and 142.0 mg/m³, respectively, while the concentration in the workplace air at the oven operating posts using regular nitrogen and the nitrogen-generating room was <0.1 mg/m³. Carboxyhemoglobin saturation levels in the 15 patients ranged from 2.000%-17.300%. Occupational acute mild carbon monoxide poisoning was diagnosed in nine patients, occupational acute carbon monoxide exposure reactions was diagnosed in six patients. This poisoning incident was caused by machine malfunction and improper operation, leading to occupational acute carbon monoxide poisoning. Conclusion Companies using nitrogen production machine should enhance their ability to identify carbon monoxide risks, strengthen training and management of workers, establish emergency response plans for nitrogen production and use, ensure proper maintenance of production equipment, and optimize operational procedures to prevent acute poisoning incidents.