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81.
甲氨基阿维菌素苯甲酸盐亚致死剂量对不同敏感性棉铃虫解毒酶活性的影响 总被引:1,自引:0,他引:1
室内用甲维盐对棉铃虫选育20代,获得敏感性降低2.32倍的汰选种群(RP20)。分别采用甲维盐对同源对照种群(CP)和RP20的亚致死浓度LC25对应处理两种群的3龄初幼虫48 h,测定试虫在3~6龄不同龄期内羧酸酯酶(CarE)和谷胱甘肽S 转移酶(GST)活性,分析酶活性变化动态。结果表明,(1)两种群(CP和RP20)均随龄期的增长,CarE比活力显著增大,而GST比活力先降低后趋于稳定。(2)CK处理下,RP20与CP相比,CarE比活力在3~6龄均增大且4~6龄差异显著,而GST比活力变化较小,仅3龄和6龄显著增大。(3)与CK处理相比,甲维盐LC25处理,两种群各龄期CarE比活力均增大,且CP试虫在4龄、6龄GST比活力显著增大,在3龄、5龄无显著差异,而RP20的3龄幼虫体内GST比活力被显著抑制,在4~6龄GST比活力无明显变化。初步判断,棉铃虫对甲维盐敏感性降低与CarE比活力增大有关;甲维盐亚致死剂量对棉铃虫CarE活性具有一定的诱导作用。 相似文献
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针对实时监测耕种机具作业中所受空间力大小,该文提出了一种能够在现场和远程实时监测耕种机具受力情况并带有提示报警的监测系统。该系统采用基于Zigbee的WSN(wireless sensor network)完成数据的采集和近程传输,采用嵌入式处理器ARM11作为现场监测终端的中央处理单元CPU,并搭建WinCE6.0操作系统,完成数据交换、处理和监测报警等功能。通过安装在耕种机具上的测力传感器,实现对耕种机具受力情况的实时检测。经土槽试验测试,系统实现了耕种机具空间力的实时监测以及监测数据的存储,人机界面交互性良好,可为耕种机具的研究设计提供技术支持。 相似文献
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Chengquan Tan Yongcheng Ji Xichen Zhao Zhongquan Xin Jiaying Li Shuangbo Huang Zhiying Cui Lijun Wen Caihua Liu Sung Woo Kim Jinping Deng Yulong Yin 《动物营养(英文)》2021,7(1):111
Increased metabolic burdens in breeding sows, which are induced by elevated systemic oxidative stress, could increase the need for nucleotides to repair lymphocyte DNA damage; however, de novo synthesis of nucleotides may be insufficient to cover this increased need. This study investigated the effects of dietary nucleotides on milk composition, oxidative stress status, and the reproductive and lactational performance of sows. Forty multiparous sows were assigned to 2 dietary treatments (Control group, and 1 g/kg Nucleotides group) based on a randomized complete block design using their BW at 85 d of gestation as a block. Sows from 2 groups were fed a restricted diet during gestation and ad libitum during lactation. The experiment lasted from 85 d of gestation to 21 d of lactation. The reproductive performance of sows and the growth performance of suckling piglets were measured. Oxidative stress parameters and milk components were also analysed. Data were analyzed using contrasts in the MIXED procedure of SAS. Sows in the Nucleotides group consumed more feed during the first week (P < 0.01) and from 1 to 21 d (P < 0.05) of lactation than those in Control group. Correspondingly, the litter weight gain of piglets showed a tendency to increase from cross-fostering to 9 d (P = 0.09) and from cross-fostering to 20 d (P = 0.10) in the Nucleotides group relative to the Control group. Additionally, the Nucleotides group was higher (P < 0.01) than the Control group in the concentrations of uridine 5''monophosphate, guanosine 5''monophosphate, inosine 5''monophosphate, adenosine 5''monophosphate and total nucleotides in milk. Furthermore, the Nucleotides group was higher (P < 0.01) than the Control group in the serum levels of total antioxidant capacity (P < 0.01) for sows at 109 d of gestation and glutathione peroxidase for weaning piglets, but lower at the levels of thiobarbituric acid-reactive substances (P < 0.05) in serum of weaning piglets. This study indicated that maternal dietary nucleotides could promote piglet growth, probably due to the higher lactational feed intake and higher concentration of nucleotides in the milk of sows, and lower oxidative stress for both sows and piglets. 相似文献
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Alisha Wehdnesday Bernardo Reyes Hannah Leah Tadeja Simborio Huynh Tan Hop Lauren Togonon Arayan Suk Kim 《Journal of veterinary science (Suw?n-si, Korea)》2016,17(1):119-122
The Brucella mdh gene was successfully cloned and expressed in E. coli. The purified recombinant malate dehydrogenase protein (rMDH) was reactive to Brucella-positive bovine serum in the early stage, but not reactive in the middle or late stage, and was reactive to Brucella-positive mouse serum in the late stage, but not in the early or middle stage of infection. In addition, rMDH did not react with Brucella-negative bovine or mouse sera. These results suggest that rMDH has the potential for use as a specific antigen in serological diagnosis for early detection of bovine brucellosis. 相似文献
88.
A continuity condition of p-forms across a p-dimensional submanifold isderived.The,various interface conditions of electromagnetic quantities are obtained through theapplication of the continuity condition to Minkowski manifold of space-time. 相似文献
89.
有机无机肥料对小麦的肥效及其交互作用 总被引:4,自引:0,他引:4
在京郊大同肥力水平土壤上,有机肥和化肥配合施用小麦增产量最高,其增量在中、高肥力试验点上大于低肥力试验点.有机肥和化肥配合施用时的增产作用是它们各自增产效应之和,它们之间的交互效应不显著.在高肥力土壤上甚至有负的交互效应,即配台施用时的增产量小于分施时各自增产量之和.根据肥料试验,本文提出了京郊不同肥力水平土壤上小麦有机无机肥料配合施用量,并发现在低肥力土壤上随着有机肥的施用,化肥氮的用量增加,化肥磷用量可减少;在高肥力土壤上随有机肥的施用,化肥氮用量减少,化肥磷用量增加;在中等肥力土壤上配合有机肥的施用,氮磷化肥用量均个应减少,应略为增加. 相似文献
90.
贵阳市乌当区某个体养鸡场鸡群发病,诊断为鸡伤寒沙门氏菌不同血清型的菌株混合感染,药敏试验表明分离菌株对部分β-内酰胺类抗生素、四环素、氟喹诺酮类、红霉素、磺胺类具有不同程度的耐药性.笔者用中药黄芩、土大黄结合阿莫西林进行治疗,取得较好效果,现报道如下. 相似文献