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101.
分离妊娠山羊子宫内膜淋巴细胞(Endometrial lymphocyte,EML)后,分别加入4、8、12、16 mg/L的亚硒酸钠进行体外培养,探讨硒对EML的活化作用及其对分泌细胞因子IL-2I、L-4、TGFβ1及TGFβ2的影响。结果显示,8~16 mg/L的亚硒酸钠可显著地促进山羊EML的体外活化(P<0.01),并呈剂量依赖性。EML活化后,对IL-2的分泌呈微弱的促进作用;对IL-4、TGFβ1、TGFβ2的分泌有显著的促进作用。 相似文献
102.
酵母硒、黄芪多糖及其复合剂对半番鸭生长性能、肉品质和抗氧化能力的影响 总被引:2,自引:0,他引:2
本文旨在研究酵母硒、黄芪多糖及其复合剂对半番鸭生长性能、肉品质和抗氧化能力的影响。从同一批饲养的22日龄半番鸭中挑选出体重相近的144只,随机分为4组,每组3个重复,每个重复12只鸭,试验期为49 d。采用2×2因子水平设计,对照组饲喂基础饲粮,试验Ⅰ组饲喂基础饲粮+0.3%酵母硒,试验Ⅱ组饲喂基础饲粮+300 mg/kg黄芪多糖,试验Ⅲ组饲喂基础饲粮+复合剂(300 mg/kg黄芪多糖+0.3%酵母硒)。试验期间测定生长性能指标,并于70日龄每组随机选择12只(每重复4只)进行屠宰,测定其胸肌肉品质和抗氧化指标。结果显示:1)试验Ⅰ组和试验Ⅱ组平均日增重、平均日采食量及料重比与对照组相比差异均不显著(P0.05);试验Ⅲ组平均日增重显著高于对照组(P0.05),平均日采食量和料重比与对照组无显著差异(P0.05)。2)与对照组相比,试验Ⅰ组、试验Ⅱ组和试验Ⅲ组24 h p H均显著或极显著提高(P0.05或P0.01),48 h滴水损失率、蒸煮损失率、剪切力显著或极显著降低(P0.05或P0.01);试验Ⅲ组肉色红度(a*)值显著提高(P0.05);试验Ⅱ组和试验Ⅲ组肉色黄度(b*)值均显著降低(P0.05)。3)试验Ⅰ组、试验Ⅱ组和试验Ⅲ组24~120 h的超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性及总抗氧化能力(T-AOC)均显著或极显著高于对照组(P0.05或P0.01);试验Ⅰ组、试验Ⅱ组48~120 h和72~120 h的丙二醛(M DA)含量分别显著或极显著低于对照组(P0.05或P0.01),试验Ⅲ组24~120 h的MDA含量极显著低于对照组(P0.01)。随储存时间延长,各组SOD、GSH-Px活性和T-AOC均呈下降趋势,MDA含量则呈上升趋势,但3个试验组各抗氧化指标的变化速度比对照组缓慢。4)酵母硒和黄芪多糖对肌肉24 h p H、剪切力、24~120 h的SOD活性、48~120 h的GSH-Px活性、120 h的M DA含量有显著或极显著交互作用(P0.05或P0.01)。由此可见,酵母硒、黄芪多糖均可改善半番鸭肌肉品质和提高抗氧化能力,降低脂质过氧化程度,有效延长货架期,且二者对于肌肉抗氧化、p H和嫩度改善均具有明显的协同效应。 相似文献
103.
Forty-eight soil profiles were sampled from different ecological and pedogeochemical areas of China and their available selenium (Av-Se) contents were determined. Results showed that the content of Av-Se in the profiles of soils in China ranged within 2.49~18.10 μg kg-1, with a mean value of 10.01 μg kg-1, and was in the sequence of Ferralisols > Luvisols > Isohumisols > Aridisols. The correlation analysis between Av-Se and the soil physical-chemical properties revealed that the correlations between Av-Se and O.M., CEC, Fe2O3, Al2O3, ignition loss, Co and Zn were positive at a highly significant level, but those between Av-Se and pH, base saturation, CaO, Ba and Sr were all negative at a highly significant level. The reason of some diseases related to the Se deficiency might be the leaching loss of selenium in some soils. 相似文献
104.
采用给小鼠颈后皮下注射D 半乳糖水溶液,同时灌胃不同浓度的纳米硒混悬液,10d后测定血浆中脂质过氧化物(LPO)、谷胱甘肽过氧化物酶(GSH PX)和超氧化物歧化酶(SOD)的活性.结果表明,D 半乳糖可使小鼠血浆LPO含量显著升高(P<0 05),GSH PX和SOD活性显著降低(P<0 05);给予纳米硒后血浆中LPO含量显著降低(P<0 05),而SOD和GSH PX活性显著升高(P<0 05).说明D 半乳糖可导致小鼠氧化损伤,纳米硒可通过提高GSH PX和SOD的活性保护D 半乳糖所致小鼠的氧化损伤. 相似文献
105.
以‘丰盛骄王’茄子为接穗,以"190-1-8""RS-2""RS-5"‘亲情’"野生番茄"为砧木,通过盆栽试验,研究了不同砧木嫁接对茄子硒富集的影响,以期筛选出能够促进茄子硒富集的砧木。结果表明:5种砧木均不同程度增加了茄子根系和地上部分生物量,以"野生番茄"的增加效果最佳。不同砧木也提高了茄子光合色素(叶绿素a、叶绿素b、叶绿素总量和类胡萝卜素)含量和过氧化物酶活性,降低了过氧化氢酶活性;不同砧木对茄子超氧化物歧化酶活性和可溶性蛋白质含量的影响不同。"RS-2"和"野生番茄"增加了茄子接穗的硒含量和硒富集量,且以"野生番茄"的增加幅度最大。因此,"RS-2"和"野生番茄"作为砧木既能促进茄子的生长,还能促进茄子对土壤硒的吸收与富集,有利于富硒茄子的生产,其中"野生番茄"的效果最佳。 相似文献
106.
富硒茶硒的浸出率及其化学性质的研究 总被引:15,自引:1,他引:14
研究了高硒土壤茶园、低硒土壤茶园、传统制茶工艺、制茶新工艺生产的富硒茶硒的浸出率、化学性质。结果表明,茶叶含硒量对富硒茶硒的浸出率无显著影响,制茶工艺对茶叶硒的浸出率影响显著,传统工艺生产的富硒茶硒的浸出率为12.40%~19.58%,红茶高于绿茶。笔者采用新工艺生产的富硒茶硒的浸出率为19.41%~29.38%,硒的浸出率提高50%。不同来源的富硒茶中近80%以上的硒为有机硒,并主要呈蛋白质结合态。富硒茶粗蛋白质中胱氨酸、甲硫氨酸的含量随茶叶含硒量提高而增加。不同来源的富硒茶含硒蛋白SDS-电泳带分析表明,富硒茶的化学性质相似,低硒土壤茶园通过施用硒肥,经茶树生物转化生产富硒茶与天然富硒茶无显著差异。 相似文献
107.
黄莉 《甘肃农业大学学报》1999,34(2):106-111
12只健康成年绵羊随机分为3组,Ⅰ组剂量Pb为10mg/kg.d和Cd1mg/kg.d口服醋酸铅和氯化镉溶液;Ⅱ组除按Ⅰ组处理外,按Se0.1mg/kg.月的剂量肌注0.2%亚硒酸钠生理盐水;Ⅲ组为健康对照组,处理后对血液、组织和被毛中主要矿物元素的含量进行了测定。结果表明:铅镉摄入后可使血液中铁和钙含量明显降低(P<001及P<0.05),被毛锌含量显著升高(P<001);肾脏中Pb、Cd含量最高,肝脏、被毛次之,全血中含量最低(肾>肝>被毛>全血)。因血液中铅镉的浓度具有较大的变异,因此认为,被毛中的Pb、Cd水平更能反映机体的中毒状况。 相似文献
108.
Supplementing copper to a fish meal based diet fed to Atlantic salmon parr affects liver copper and selenium concentrations 总被引:1,自引:0,他引:1
The present experiment was conducted to study growth and tissue responses in Atlantic salmon, Salmo salar L., fed a fish meal based diet supplemented with copper (Cu). The findings of the experiment were used to evaluate the need for dietary Cu supplementation. Atlantic salmon parr, initially weighing ≊ 7.5 g, were randomly distributed among 10 tanks, with 300 fish in each tank. Duplicate groups of fish were fed a fish meal based diet containing 3.5 mg Cu kg−1 , or this diet supplemented with 5, 10, 50 or 100 mg Cu kg−1 (as CuSO4 *5 H2 O) for 12 weeks. Growth was recorded and blood haemoglobin measured. The Cu concentrations in whole body, liver, serum and selected muscle samples were measured, as was liver selenium (Se) concentration.
There were no difference in growth among the dietary treatments. There were, however, significant differences among the dietary groups in liver Cu and Se concentrations. The fish fed the diet supplemented with 5 mg Cu kg−1 had increased liver Cu concentration compared with the other groups. Similar trends were found for serum Cu concentration and whole-body Cu concentration, but these effects were not significant. Liver Cu and Se concentrations were positively correlated and liver Se concentrations were inversely correlated to dietary Cu concentration, confirming an interaction between these two elements in salmon.
There may be a positive effect of a modest Cu supplementation level, and we suggest that a small amount of Cu (5–10 mg kg−1 ) should be added to fish meal based diets. 相似文献
There were no difference in growth among the dietary treatments. There were, however, significant differences among the dietary groups in liver Cu and Se concentrations. The fish fed the diet supplemented with 5 mg Cu kg
There may be a positive effect of a modest Cu supplementation level, and we suggest that a small amount of Cu (5–10 mg kg
109.
富硒酵母对斑点叉尾鮰肝脏的毒性作用及蛋白质组学的影响 总被引:1,自引:0,他引:1
实验探讨了富硒酵母对斑点叉尾鮰肝脏的毒性作用及蛋白质组学的影响,结果表明,饲养56 d后正常组和有机硒组采用原子荧光法检测硒含量均值为0.15和0.81 mg/kg。H.E染色显示有机硒组肝细胞有明显的疏松化,部分发生脂肪变。通过二维凝胶电泳结合ImageMaster软件分析,鉴定出8个表达差异蛋白质点,其中3个在有机硒组表达上调,5个在有机硒组特异表达,经液相色谱串联质谱分析鉴定,这些蛋白质分别是伴侣蛋白TCP1-亚基8、甘油醛-3-磷酸脱氢酶、4SNcTudor蛋白、腺苷激酶、酮糖移转酶、丙氨酰-tRNA合成酶。富硒酵母饲料对斑点叉尾鮰肝具有明显的毒性效应,有机硒调控4SNc-Tudor蛋白,通过信号传导通道加强机体免疫。 相似文献
110.
Synbiotic effect of Bacillus mycoides and organic selenium on immunity and growth of marron,Cherax cainii (Austin, 2002) 下载免费PDF全文
The present feeding trial examined the effect of synbiotic use of Bacillus mycoides and organic selenium (OS) as Sel‐Plex on marron immunity, growth and survival. The marron were cultured in recirculated tanks and fed test diets consisting of a basal diet; basal diet supplemented with B. mycoides (108 CFU g?1 of feed); basal diet supplemented with OS (Sel‐Plex) (0.2 g kg ? 1 of feed) and basal diet supplemented with synbiotic (B. mycoides at 108 CFU g?1 and OS 0.2 g kg ? 1 feed) diet, in triplicate. The effect of the prebiotic OS (Sel‐Plex) on the growth rate of B. mycoides was also studied in vitro. The results suggested that synbiotic use of B. mycoides and OS significantly improved some immune parameters of marron, particularly the glutathione peroxidase, and to some extent total haemocyte counts. However, the synbiotic feed did not synergistically improve marron growth, in fact the use of B. mycoides‐supplemented diet alone demonstrated significantly higher growth in marron compared with the growth of marron fed on other test diets. Supplementation of the basal diet with host origin B. mycoides significantly increased the intestinal bacterial population (3.399 ± 825 CFU g ? 1 of gut) in marron compared with other diets. Organic selenium as Sel‐Plex in Trypticase Soya Broth also confirmed that OS did not increase the amount of growth of B. mycoides and resulted in a lower intestinal bacterial population in the synbiotic diet‐fed marron. In conclusion, synbiotic of OS and B. mycoides may improve a particular immune parameters of marron and to a lesser extent their growth. 相似文献