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141.
AIM: The influence of the seawater on the lipid peroxidation of the muscle tissue wounded by firearm was studied. METHODS: Both two limbs of rabbits were wounded by the steel ball of 250 mg. The wounded rabbits were divided into two group: One is seawater immersed group (SIG), which was dipped in artificial seawater for 30 min. Another is the single wounded group (SWG), which wasn't dipped in seawater. Then, muscle tissues 0.5 cm (A area), 1.5 cm (B area) and 2.5 cm (C area) from wound edge were cut for biochemical analysis at 3, 6, 12, 24 h of post-wound, respectively. The contents of ATP, MDA and SOD activity of all these tissues were detected, pre-wounded muscle tissues were used as control group. RESULTS: The content of MDA in SIG increased obviously at 3, 6 h, respectively, but it decreased slightly at 12 h and increased again at 24 h. The change in MDA in SWG is similar to that in SIG but more slightly. The changes in both the activity of SOD and the content of ATP in two groups is similar to that of MDA. CONCLUSION: Seawater induced more serious lipid peroxidation in the muscle tissue wounded by firearm.  相似文献   
142.
用不同氯化钠浓度的Hogland营养液进行水培试验,结果表明,随盐分浓度增高,叶片丙二醛含量增加,膜透性增强,过氧化物酶活性升高,叶片相对含水量降低。抗盐性品种的膜脂质过氧化反应水平较低,过氧化物酶活性较高。  相似文献   
143.
BACKGROUND: QoI fungicides, inhibitors of mitochondrial respiration, are considered to be at high risk of resistance development. In several phytopathogenic fungi, resistance is caused by mutations (most frequently G143A) in the mitochondrial cytochrome b (cytb) gene. The genetic and molecular basis of QoI resistance were investigated in laboratory and field mutants of Botryotinia fuckeliana (de Bary) Whetz. exhibiting in vitro reduced sensitivity to trifloxystrobin. RESULTS: B. fuckeliana mutants highly resistant to trifloxystrobin were obtained in the laboratory by spontaneous mutations in wild‐type strains, or from naturally infected plants on a medium amended with 1–3 mg L?1 trifloxystrobin and 2 mM salicylhydroxamic acid, an inhibitor of alternative oxidase. No point mutations were detected, either in the complete nucleotide sequences of the cytb gene or in those of the aox and Rieske protein genes of laboratory mutants, whereas all field mutants carried the G143A mutation in the mitochondrial cytb gene. QoI resistance was always maternally inherited in ascospore progeny of sexual crosses of field mutants with sensitive reference strains. CONCLUSIONS: The G143A mutation in cytb gene is confirmed to be responsible for field resistance to QoIs in B. fuckeliana. Maternal inheritance of resistance to QoIs in progeny of sexual crosses confirmed that it is caused by extranuclear genetic determinants. In laboratory mutants the heteroplasmic state of mutated mitochondria could likely hamper the G143A detection, otherwise other gene(s) underlying different mechanisms of resistance could be involved. Copyright © 2012 Society of Chemical Industry  相似文献   
144.
[目的]研究培养条件对梅尼小环藻细胞生长和油脂积累的影响,以获得其产油的最佳培养工艺。[方法]采用干重法评价梅尼小环藻的生物量,采用溶剂浸提法测定微藻中油脂含量,并通过单因子试验考察培养温度、初始pH、光照强度、摇床转速、接种量对梅尼小环藻细胞生长和油脂积累的影响。[结果]梅尼小环藻产油最佳培养工艺为:培养温度25℃、初始pH 8.0、光照强度600 lx、摇床转速130 r/min、接种量20%。在上述优化条件下培养5 d,梅尼小环藻的生物量和油脂含量可达到5.4 g/L和56%,分别为对照组的1.38和1.30倍。[结论]研究结果为大规模化生产微藻油脂提供了理论依据。  相似文献   
145.
总结了近几年有机硅废水的处理方法,有物理法、化学氧化法、气提处理工艺、微电解处理工艺和生化处理工艺等,并结合近几年国内外的研究成果,介绍了国内外有机硅废水的深度处理技术,同时对有机硅废水处理技术的发展趋势进行了展望。  相似文献   
146.
以土壤中常见的锰氧化物(水钠锰矿,δ-MnO2)为材料,通过批试验研究了其对溶液中As(Ⅲ)的吸附和氧化机制。研究结果表明:大部分加入的As(Ⅲ)(1.0mg/L)在反应的数分钟内就可被锰氧化物氧化,氧化产物As(Ⅴ)的释放速度相当快,但还原产物Mn(Ⅱ)的释放速度则相对较慢;在反应的90min内,当初始质量浓度为0.5、1.0、5.0、10.0和15.0mg/L时,As(Ⅲ)去除率可分别达到93.59%、92.56%、92.31%、89.15%和87.17%。pH对锰氧化物氧化As(Ⅲ)的影响较为显著,升高pH有利于锰氧化物对还原产物Mn(Ⅱ)的吸附,但不利于As(Ⅲ)的氧化和对氧化产物As(Ⅴ)的吸附。  相似文献   
147.
研究冻干马鲛鱼调理制品前处理的工艺优化条件,结果表明:0.1%维生素C和0.02%TBHQ复配作为鱼肉抗氧化剂;抗氧化处理工艺参数:浸泡温度5℃、浸泡时间10min、料液比为1:2;鱼肉附味配方为:食用盐1.5%、I+G0.02%、酱油6%、姜汁1.5%;防肉质破损蒸煮工艺参数:0.3%山梨糖醇液、处理浸泡时间90s、蒸煮温度95℃、蒸煮时间3min。  相似文献   
148.
杨金兰  阎杰  严卓晟  陈森霞 《广东农业科学》2012,39(11):113-115,127
以青竹叶为原料、乙醇为萃取剂,利用超声波辅助提取其中的黄酮类物质。研究了溶剂浓度、料液比、搅拌速度、超声波功率、萃取时间、萃取次数等因素对产物得率的影响。结果表明:常温下,乙醇浓度为75%,料液比为1∶15(g/mL),搅拌速度为80r/min,超声功率为30 W,单次萃取时间为25 min,萃取3次,黄酮提取率最高为2.91%。与常规提取方法相比,超声波法具有省时节能、提取率高等优势。对油脂氧化抑制作用研究表明,竹叶黄酮具有良好的抗氧化性,可以作为天然绿色的抗氧剂进行开发。  相似文献   
149.
One experiment was conducted to determine the nutritive value of cholesterol for post-larval shrimp, Litopenaeus vannamei. Four isoenergetic and isonitrogenous diets supplemented with four levels of cholesterol (D1, D2, D3 and D4 with 0, 0.5%, 1% and 2% cholesterol, respectively) were fed to triplicate groups of L. vannamei shrimp (mean initial wet weight 0.8 mg) for 27 days. After the trial, shrimp fed the D1 diet had the best growth performance (final body weights: FBW; weight gain: WG; specific growth rate: SGR), while there was no significant difference between diet treatments with respect to survival. The whole body crude protein level in the shrimp decreased with the increase in dietary cholesterol levels, while the whole body crude lipid level in shrimps in the D4 diet treatment was significantly higher (P < 0.05) than in other diet treatments. Dietary analysis indicated that the D1 diet contained 0.92% cholesterol prior to supplementation, which may have satisfied the dietary cholesterol requirement of post-larval L. vannamei; excess dietary cholesterol may thus lead to adverse effects on the growth performance of post-larval shrimp.  相似文献   
150.
指出了组合式污水处理设备是针对我国目前的分散型生活污水的收集和处理的实际进行开发和设计的,采用2级厌氧和2级好氧的完全混流曝气技术。从处理效率高、抗冲击负荷强、占地面积小等方面分析了组合式污水处理设备的优势,探讨了其在洱海湖滨带污水治理中的应用。  相似文献   
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