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甘露寡糖、中药和微生态制剂对肉鸡抗氧化性能的影响 总被引:3,自引:0,他引:3
1992只1日龄AA肉鸡随机分为4个处理组,饲喂四种不同的日粮。42日龄测定各组肉鸡组织及血清抗氧化指标的水平。结果表明:(1)除心脏和血清外,各试验组MDA含量均与Ⅳ组差异显著(P〈O.05)。(2)肝脏中SOD变化较明显,各试验组均高于Ⅳ组,且差异显著(P〈O.05)。心脏各组之间差异不显著。(3)心脏GSH—Px含量以Ⅱ、Ⅲ组较高,且均与Ⅳ组差异显著。血清以Ⅱ组最高,且与其他各组之间差异显著(P〈0.05)。(4)心脏T—AOC含量变化较大,各试验组均高于Ⅳ组,且差异显著(P〈0.05)。血清以Ⅱ组最高,且与其他试验组差异显著(P〈0.05)。 相似文献
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啤酒酵母葡聚糖对断奶仔猪生产性能及淋巴细胞转化率的影响 总被引:4,自引:1,他引:4
为了探讨啤酒酵母葡聚糖在断奶仔猪日粮中的适宜添加剂量及其对断奶仔猪细胞免疫功能的影响,本研究进行了2个试验。试验1选用100头(28±2)d断奶的二元杂交断奶仔猪,按单因子试验设计随机分为5个处理,分别饲喂含葡聚糖0、25、50、100mg/kg和200mg/kg的日粮。结果表明:随葡聚糖添加剂量的增加,平均日增重在14 ̄28 d及0 ̄28 d呈二次曲线变化(P<0.05)。试验2选用80头(28±2)d断奶的二元杂交断奶仔猪,随机分为2个处理,分别饲喂含葡聚糖0mg/kg和50mg/kg的日粮。在试验的第14天和第28天,每重复取1头仔猪前腔静脉采血,测定外周血淋巴细胞转化率。结果显示,在断奶仔猪日粮中添加50mg/kg葡聚糖提高了仔猪在14 ̄28d及0 ̄28d的日增重(P<0.05)。而且,也提高了仔猪在0 ̄14 d、0 ̄28 d及28 ̄35 d的平均日采食量(P<0.05)。但是对淋巴细胞转化率没有影响。结果表明:在断奶仔猪日粮中添加50mg/kg啤酒酵母葡聚糖,可以提高断奶仔猪的生产性能,而且没有性别差异。 相似文献
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AIM:To investigate the protective effect of insulin like growth factor-1 (IGF-1) against radiation-induced injury in c17.2 neural stem cells.METHODS:c17.2 neural stem cells were cultured in vitro and identified by nestin immunohistochemistry and X-gal staining.The IGF-1 adenoviral vector was transfected into c17.2 neural stem cells.The expression of IGF-1 was detected by IGF-1 immunohistochemistry.Necrosis and apoptosis of c17.2 neural stem cells were induced by radiation at doses of 4 Gy,6 Gy and were detected by flow cytometry and TUNEL test.The effect of IGF transfection on the degree of necrosis and apoptosis in these cells was also observed.RESULTS:c17.2 cells were identified by nestin and X-gal staining.Immunohistochemistry verified the expression of IGF-1 in the c17.2 neural stem cells transfected with adenoviral vector.At the same doses of radiation,the rates of apoptosis and necrosis in c17.2 neural stem cells transfected with IGF-1 were lower than those in the cells without IGF-1 adenoviral vector transfection.CONCLUSION:The rate of necrosis and apoptosis of c17.2 neural stem cells induced by radiation is decreased by transfection of IGF-1 adenoviral vector.IGF-1 shows a protective effect on c17.2 cells. 相似文献
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WANG Hui-ying ZENG Yao-ying WANG Tong XING Fei-yue ZHAO Jing-xian JI Yu-hua 《园艺学报》2006,33(5):1020-1023
AIM: To study the effects of ultraviolet (UV) on mitochondrial functions and apoptosis in HaCaT cells. METHODS: After irradiation by UV at low dose (UVA 2 J/cm2,UVB 10 mJ/cm2) and high dose (UVA 6 J/cm2,UVB 30 mJ/cm2), HaCaT cells were cultured for 15 hours. Flow cytometry was used to measure mitochondrial membrane potential, mitochondrial mass and apoptotic rate. Annexin V-FITC/PI staining of apoptotic cells was analyzed by laser confocal microscopy. RESULTS: After UV irradiation, cell proportion with low mitochondrial membrane potential increased with irradiation doses. The proportion of control group, low dose group and high dose group were 7.94%±1.02%, 25.87%±4.55% and 39.27%±5.32%, respectively. Cells proportion with low mitochondrial mass increased with irradiation doses. The proportion of control group, low dose group and high dose group were 15.19%±1.58%, 40.36%±4.41% and 68.79%±5.46%, respectively. The hypodiploid peaks of DNA content analysis represented the apoptotic rate of HaCaT cells. The apoptotic rate of control group, low dose group and high dose group were 1.82%±0.51%, 30.16%±5.47% and 58.49%±5.98%, respectively. To analyze the cells apoptosis by staining with annexin V-FITC and PI, the results were consistent with those of DNA content analysis. Cells in control group showed almost no positive staining cells. Single annexin V-FITC positive cells in low dose group and double positive cells in high dose group were predominant, respectively. CONCLUSION: UV irradiation induces HaCaT cell mitochondrial depolarization, as well as mitochondrial mass loss. These changes are related to cell apoptosis. 相似文献
79.
鸡β-防御素在大肠杆菌中的高效表达及复性 总被引:2,自引:0,他引:2
鸡β-防御素(gallinacin-3,Gal3)是鸡体内重要的防御因子,本试验研究了鸡Gal3融合蛋白在大肠杆菌中高效表达的规律,并探索了重组蛋白质的复性工艺.结果表明,加入诱导剂后1h,开始有可检出量的重组蛋白质表达,2h的表达水平已接近最大量;化学诱导剂IPTG 0.2~1.2mol/L对重组蛋白的产量没有明显影响.经Lablmage软件分析,融合蛋白的产量可达菌体总蛋白的35%以上,且主要以包涵体形式存在.将所获包涵体用8mol/L尿素溶解后,分步稀释于含有氧化型谷胱甘肽和还原型谷胱甘肽的复性系统中,重组蛋白得到完全复性.12mg/L复性的重组鸡Gal3能抑制肠炎沙门氏菌的生长,24mg/L能抑制肠致病型大肠杆菌的生长. 相似文献
80.