The effects of chronic administration of technical benzene hexachloride on histological pattern of liver and kidney in rat and mixed function oxidase system of liver microsomes were studied. Administration of BHC brought about increase in the liver weight, vacuolar of hepatic cells and hydropic degeneration of the epithelial cells of the renal tubules. Through electromi-croscopic examination, we discovered that there were proliferation and expansion of the smooth endoplasmic reticulum, swelling of the mitochondria in the cytoplasm in the liver cells and kidney cells and increase in the number of lysosome in the epithelial cells of the renal tubles.Administration of BHC stimulated an increase in the tissue storage and urinary excretion of ascorbic acid and induced mixed-function oxidase system of liver microsomes.Supplementation of L-ascorbic acid in high doses under the toxic conditions significantly improved pathological damage of the liver and kidney cells, decreased residuary amount of BHC in the tissue, and facilitated the induction of mixed-function oxidase system of liver microsomes by BHC.

Objective: To investigate the effect of soy isoflavones extract on bone loss induced by estrogen deficiency. Methods: 87 postmenopausal women were randomly assigned in single blind manner, to three treatment groups with daily intake of placebo, 84 mg and 126 mg soy isoflavones respectively. Additionally a positive control group was 10 women was given daily 2.5 mg estrogen. Bone mineral density (BMD) of the lumbar spine, neck of femur and Ward`s triangle were measured at baseline and post treatment after 24 wk . Results: BMD in all sites in both isoflavones treated and estrogen treated groups did not change significantly. However, the BMD of the lumbar spine decreased in the placebo group (P

Objective: To study the effect of different ratios of n-6 to n-3 polyunsaturated fatty acid on serum lipid in mice, on the premise that the ratio of SFA to MUFA to PUFA is 1∶1.7∶1.2 or 1∶1∶1. Methods: Ten experimental diets were made from six oils different in fatty acid composition to raise the mice for 10 w. Then the blood lipids were determined in mice fed with different experimental diets. Results and conclusion: Based on the ratio of S/M/P 1∶1.7∶1.2, which is the current dietary fatty acid intake, n-6/n-3 at 1~5∶1 will have lower serum lipid level. Based on the ratio of S/M/P 1∶1∶1 , n-6/n-3 at 1∶1 will have lower serum lipid level. Based on the ratio of n-6 /n-3 10∶1 which is the current dietary fatty acid composition abroad , S/M/P 1∶1.7∶1.2 will have lower serum lipid level.

Objective: To study the effects of dietary n-6/n-3 PUFA ratio on T lymphocyte functions in mice. Methods: 96 male BALb/c mice were randomly divided into 8 groups with dietary S:M:P 1:1.5:3.7 or 1:1.5:1, respectively. The n-6/n-3 PUFA ratio was 1, 7.5, 15, 30 respectively in each S:M:P diet. Each diet contained 70.0g/kg lipid,and different n-6/n-3 PUFA ratios by mixing different oils. At the end of 12w, all mice were killed and blood was collected. The spleen T lymphocyte proliferation, IL-2 production and serum MDA were measured. Results: When dietary S:M:P was 1:1.5:3.7, the proliferation of spleen lymphocytes and IL-2 production from mice with dietary n-6/n-3 ratio 1 were suppressed (P

【Objective】 To study the effects of docosahexaenoic ac id (DHA) and arachidonic acid (AA) intake on the visual and cognitive function o f preterm infants. 【Methods】 32 preterm infants (gestational age<37 weeks) wer e divided into three groups which were fed with different formula respectively: group A, breast milk(n=11); group B, a conventional formula lacking DHA and AA (n=10); group C, DHA and AA enriched formula (n=11). Group C was stop ped to fed enriched formula when infant's weight reached (2.50±0.10) kg. Cognitiv e function was evaluated by NBNA test when the corrected age of each preterm inf ant was 42 week±7 day, ERG of both eyes was tested at three-months old. The ex periment lasted for three months. 【Results】 Cognitive and visual function of g roup C were similar to group A, however, some indexes of group B were significan tly lower than group A and C (P<0.05). 【Conclusion】 Adding DHA and AA to f ormulas similar to breast milk in amounts, can improve cognitive and visual func tion of preterm infants, and help these infants to achieve similar cognitive and visual function to those breast-milk-fed preterm infants.

Objective: To study the mechanism of the preventive effects of soybean isoflavones on osteoporosis. Methods: The serum collected from experimental rats given soybean isoflavones extract was added to the culture system of osteoblast cells (OB) isolated from the calvaria of neonatal SD rats. MTT assay was employed to determine cell proliferation. The activity of alkaline phosphatase (ALP) and bone gla protein (BGP) were determined by ALP and BGP Kits. The content of IL 6 secreted by OB was determined by ELISA Kit. Results: Isoflavones could stimulate OB proliferation, elevate the activity of ALP and BGP level. They had no apparent effects on the secretion of IL 6. Conclusion: Soybean isoflavones can promote proliferation and differentation of OB in vitro and have no remarkable influence on bone absorption. The effects of soybean isoflavones on osteoporosis seem to depend on stimulation of bone formation rather than suppression of bone absorption.

950 mg/d) group was significantly higher than those in median or low calcium intake group,among girls with BB genotype. However,such significant effect was not detected among girls with b allele. Conclusion:The PTH BstBⅠ polymorphism has significant interaction effect with calcium intake on bone mass accretion in Chinese adolescent girls. High calcium intake would be beneficial to gain higher bone mass accretion for girls with BB genotype than those with b allele.

Objective:To investigate the characteristics of calcium metabolism and identify the calcium intake that produces plateau retention in premenarche Chinese girls. Method:Forty-nine healthy premenarche Chinese girls (9-11.5 y) were recruited, and divided into four groups respectively receiving one of four different doses of calcium intakes for 6 d, 600 mg (usual diet),900 mg (containing 250 ml milk),1 200 mg (containing 250 ml milk and 750 mg CaCO3) and 1 500 mg calcium (250 ml milk and 1500 mg CaCO3) per day. Calium in 3-day urine and stool,and 3-d duplicated food samples were collected to assess the calcium equilibrium during the treatment period. Results: There were no significant differences in apparent calcium absorption among the four groups (55%, 53%, 52% and 52%). The relationship between calcium intake and calcium retention was fitted into a non-liner regression model which showed that the calcium retention was approaching the plateau when calcium intake reached 1100mg/d. Conclusion: The apparent calcium absorption was 53%?0.12% in Chinese premenarche girls with dietary calcium intakes ranged between 600 to 1500 mg/d. Calcium retention approached its plateau when calcium intake reached 1 100 mg/d in Chinese premenarche girls.

Thirty-six healthy women were divided into 3 groups according to their calcium intake at week 18 of gestation. The levels of their blood calcium, phosphate, parathyroid hormone (PTH) and calcitonin were assayed during pregnancy and postpartum, and bone mineral density ( BMD) was measured postpartum. The levels of PHI and calcitonin were increasing with advancing pregnancy and reached the highest at the end of pregnancy. The women with higher calcium intake during pregnancy period had higher BMD than that of the women with ordinary diet during pregnancy period.

Objective:To assess the proportion of genotypes of osteocalcin gene polymorphism, and to investigate if the polymorphism of osteocalcin gene is associated with BMD in Chinese premenarche girls. Methods: 152 healthy premenarche girls of Han ethic (9-11.5y) were recruited. BMD and BMC at the lumber spine (L1-L4), proximal femur, and total body were measured by DXA; PCR-RFLP was used to amplify the polymorphisms of the osteocalcin gene. Results:The proportion of genotype of OC gene polymorphism were 5.26% HH,, 36.84% Hh, and 58.90% hh, respectively. Significant differences were observed in BMD and BMC at the total body, and BMD at the L1-L4 lumber spine and femur neck among subjects with different genotypes (P