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41.
种子在自然贮藏过程中常常伴随着内部生理机能的恶化,线粒体作为种子内活性氧(reactive oxide species,ROS)产生的主要位点是最先遭到破坏的细胞器。为探讨不同贮藏年限对老芒麦种胚线粒体抗氧化功能的影响,本试验以室温贮藏0~4年的老芒麦种子为材料,分析比较其老化规律及种胚线粒体抗氧化特性的变化规律。结果表明:随着贮藏年限的延长,老芒麦种子发芽势、发芽率和种苗鲜重逐渐下降,死种子逐渐增多,种胚线粒体苹果酸脱氢酶(mitochondria malate dehydrogenase,MDH)、谷胱甘肽还原酶(glutathione reductase,GR)、单脱氢抗坏血酸还原酶(monodehydroascorbate reductase,MDHAR)活性逐渐下降,但在死种子中超氧化物歧化酶(superoxide dismutase,SOD)活性显著升高。此外,在贮藏过程中老芒麦种胚线粒体O2·-产生速率不断上升,而H2O2含量则呈现逐渐降低的趋势,表明线粒体中O2·-的积累与细胞氧化损伤密切相关。 相似文献
42.
TIR1/AFBs基因家族是一种存在于细胞核中的生长素受体,属于F-box蛋白基因中的一个小亚族。它们通过与相关生长素相结合活化转录因子来促进基因的表达,从而进行调控,是生长素信号转导过程中的关键部分。为了深入研究生长素信号转导机制,从TIR1/AFBs基因家族的发现与结构,家族成员表达模式的差异及对植物生长发育方面的调节等方面概括介绍了TIR1/AFBs基因家族的分子调控机制,总结了TIR1/AFBs基因的功能。最后探讨了TIR1/AFBs基因的研究方向。 相似文献
43.
44.
The assay was aimed to study the effect of Hedyotis diffusa Willd superfines powder on immune function. Three groups of mice were gavaged with the drugs at doses of 1.75,1.25 and 0.75 g/kg once a day for 7 consecutive days, repectively. The mice of control group were administered with the same volume of saline.At the last time, mice were injected into the muscle with Newcastle disease vaccine,and get peripheral blood on days 7, 14 and 21 after the medicine administration. The enhancement of innate immune responses were evaluated by using CCK-8 method, hemagglutination inhibition test, macrophage phagocytic function test and organ coefficient method. The levels of lymphocytes proliferative capacity, serum antibody, peritoneal macrophage phagocytosis and the indexes of immune organs in mice were extremely significantly enhanced (P<0.01). Hedyotis diffusa dWilld superfines powder could extremely significantly regulate the immunity function of mice (P<0.01). 相似文献
45.
《东北农业大学学报(英文版)》2016,(2):82-88
Along with the rapid advance of industrialization and urbanization process, fostering new agricultural business entities become inevitable for agricultural transformation and the construction of agricultural modernization in China. The status of the new agricultural business entities determines the level of modern agricultural development. In recent years, new agricultural business entities have grew rapidly. However, there are still many problems including the difficulties in financing loans, inadequate agricultural insurance system, bad implementation of agricultural subsidies, jagged agricultural talents and so on. In order to foster new agricultural business entities, countermeasures should be carried out to ensure financial support, perfect the agricultural insurance, strengthen the level of agricultural subsidies, strive to develop the degree of specialization agricultural operators and so on. 相似文献
46.
为明确番茄潜叶蛾Tuta absoluta(Meyrick)成虫触角及幼虫头部感受器的种类、分布和形态结构,采用扫描电镜法观察番茄潜叶蛾雌雄成虫触角和4龄雌雄幼虫触角及口器上的感受器种类和形状。结果显示,番茄潜叶蛾成虫触角上共有8种类型感受器,分别为B?hm氏鬃毛、毛形感受器、鳞形感受器、锥形感受器(Ⅰ型和Ⅱ型)、刺形感受器、腔锥形感受器、栓锥形感受器和耳形感受器。其中,雌成虫的Ⅰ型和Ⅱ型锥形感受器数量、刺形感受器数量、B?hm氏鬃毛长度、鳞形感受器长度及基部直径、Ⅰ型锥形感受器长度及基部直径、Ⅱ型锥形感受器长度、刺形感受器臼状窝直径、腔锥形感受器基部直径和耳形感受器基部直径均显著大于雄成虫;而雄成虫的毛形感受器数量和腔锥形感受器中心锥长度显著大于雌成虫。幼虫头部共计有6种类型感受器,主要着生在触角、下颚和下唇上,分别为毛形感受器、锥形感受器、刺形感受器、栓锥形感受器、指形感受器和感觉锥;幼虫触角、下颚和下唇的感受器类型和数量在雌雄间完全相同。而雌性幼虫触角鞭节上的锥形感受器SB5和下颚须上的锥形感受器SB2的长度显著大于雄性幼虫;雄性幼虫下颚茎节上的刺形感受器Sch1和下颚须上的锥形... 相似文献
47.
陈玉米饲粮中添加茶多酚、维生素E和二丁基羟基甲苯对肉鸭生长性能和抗氧化功能的影响 总被引:1,自引:0,他引:1
本试验旨在研究陈玉米饲粮中添加茶多酚(TP)、维生素E和二丁基羟基甲苯(BHT)对肉鸭生长性能和抗氧化功能的影响。选取1日龄雄性北京鸭192只,随机分为4组,每组6个重复,每个重复8只。以储存3年玉米作为能量原料,Ⅰ组(对照组)饲喂基础饲粮(不添加饲料抗氧化剂),Ⅱ、Ⅲ、Ⅳ组分别饲喂在基础饲粮中添加120 mg/kg TP、维生素E和BHT的试验饲粮。试验期42 d。结果表明:1)与对照组相比,TP能显著提高22~42日龄肉鸭平均日增重(P0.05),维生素E能显著提高1~21日龄和22~42日龄肉鸭平均日增重(P0.05),BHT对肉鸭生长性能无显著影响(P0.05)。2)与对照组相比,TP能显著提高21和42日龄血清总抗氧化能力(T-AOC)以及42日龄血清过氧化氢酶(CAT)活性(P0.05),维生素E能显著提高42日龄血清CAT活性(P0.05);BHT能显著提高21日龄血清T-AOC以及21和42日龄血清CAT活性(P0.05)。由此可见,陈玉米饲粮中添加TP和维生素E对肉鸭生长性能以及抗氧化功能均有不同程度的改善,而BHT只改善了肉鸭的抗氧化功能。陈玉米饲粮中添加TP效果最好。 相似文献
48.
This experiment was conducted to study the effects of different levels of compound Chinese medicine on growth performance,nutrients apparent digestibility,immune function and slaughter performance of weaning Rex rabbits.70 healthy Rex rabbits at age of 60 days were divided into 7 groups with 5 replicates per group and 2 rabbits per replicate.Group Ⅰ was fed with basic diet as control group,group Ⅱ was fed the basal diet supplemented with antibiotic (contains 50 mg/kg milligrams bacitracin zinc,10 mg/kg colistin sulfate).The other five groups (Ⅲ,Ⅳ,Ⅴ,Ⅵ and Ⅶ) were fed the basal diet supplemented with 1%,2%,3%,4%,5% compound Chinese medicine,respectively.The pre-test period lasted for 7 days and the trial period lasted for 45 days.The results showed as follows:①The ADG in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ and Ⅲ (P< 0.05),the F/G in group Ⅳ was significantly lower than that in other groups (P< 0.05).②The apparent digestibility of DM in group Ⅳ was significantly higher than that in groups Ⅰand Ⅱ (P< 0.05),the apparent digestibility of DM in group Ⅶ was significantly higher than that in group Ⅰ (P< 0.05).The apparent digestibility of CF in group Ⅳ was extremely significantly higher than that in group Ⅰ (P< 0.01),the apparent digestibility of CF in group Ⅶ was significantly higher than that in group Ⅰ (P< 0.05).The apparent digestibility of NDF in group Ⅳ was extremely significantly higher than that in group Ⅰ (P< 0.01),and significantly higher than that in groups Ⅱ,Ⅲ,Ⅴ and Ⅶ (P< 0.05).The apparent digestibility of ADF in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ,Ⅴ and Ⅶ (P< 0.05).The apparent digestibility of CP in group Ⅳ was significantly higher than that in groups Ⅰ and Ⅱ (P< 0.05).③ There were no significant differences in the contents of IgG,IgA and IgM of serum among all groups (P> 0.05),the spleen index in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ,Ⅲ and Ⅴ (P< 0.05).④There were no significant differences in the slaughter rate,half eviscerated slaughter rate and all eviscerated slaughter rate among all groups (P> 0.05).In summary,adding compound Chinese medicine and antibiotics in the feed both could improve the growth performance,nutrients apparent digestibility,immune function and slaughter performance of weaning Rex rabbits,and the appropriate compound Chinese medicine level in the diet of weaning Rex rabbits was 2%. 相似文献
49.
透明质酸是一种在体内广泛分布的黏多糖,已成功用于骨科、眼科、整形美容、保健食品等领域,但仍有许多新的应用领域不断被开发。主要介绍了透明质酸的生理功能,并结合透明质酸的结构特性,综述了透明质酸在保健食品、化妆品、美容、骨科、眼科等几个方面应用的研究进展。 相似文献
50.
为比较肉雏鸡在饮水中添加干酪乳杆菌与氟苯尼考对肉雏鸡生长性能与免疫力的影响,本试验选取1日龄肉鸡120只,随机分为3个处理组,分别为对照组、干酪乳杆菌组、氟苯尼考组,每个处理组4个重复,每个重复10只,试验期为21 d,检测不同阶段各处理组的平均日增重、料重比、免疫器官指数、外周血IgG含量、盲肠sIgA含量、淋巴细胞增殖能力。结果显示,饮水中添加干酪乳杆菌对肉雏鸡体重、平均日增重、平均日采食量影响不显著,添加氟苯尼考显著抑制了肉雏鸡的生长性能(P0.05),二者对肉雏鸡料重比的影响均差异不显著。添加干酪乳杆菌对肉雏鸡免疫器官指数影响不显著,但显著提高了肉雏鸡外周血IgG含量、盲肠sIgA含量以及外周血淋巴细胞增殖能力(P0.05),添加氟苯尼考显著抑制了肉雏鸡的免疫水平(P0.05)。结果表明新进肉雏鸡在饮水中添加氟苯尼考对雏鸡的生长性能及免疫力有显著的抑制作用,应减少使用,而添加干酪乳杆菌对提高雏鸡免疫力是有益的。 相似文献