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31.
RAN Xu-hua ZHANG Yao CAO Si LU Yuan-he ZHANG Ling-ling LIU Yang-yang NI Hong-bo ZHU Zhan-bo WEN Xiao-bo 《中国畜牧兽医》2016,43(5):1368-1373
To identify the infection agents from Ningxia Hui Autonomous region, where feedlot cattle indicated bovine respiratory disease complex (BRDC), the M gene of the bovine parainfluenza virus type 3 was amplified by RT-PCR.The PCR product was ligated to pMD18-T vector and cloned to E.coli DH5α.The positive clones were sequenced and compared with the reference strains in GenBank by the molecular biology software.Sequence alignment results showed that a BPIV3 strain was isolated from the samples and named NX49, the M gene of NX49 included 1 056 nucleotides.Evolutionary analysis showed that the NX49 belonged to BPIV3 C genotype and shared 99.4% nucleotide identity with that of the SD0835 isolated in Shandong province.The characterization of the NX49 demonstrated that it was sensitive to temperature, acid and organic matter.The presence of Mg2+ showed no protection against the treatment at high temperature.The HA test suggested that the NX49 enables to agglutinate the guinea pig RBC at 4 ℃ and the titer was 1∶4.The study isolated a BPIV3 genotype C strain successfully, which facilitate the study of molecular evolution and epidemiology of BPIV3 in China. 相似文献
32.
Xiao-ying He Li-bing Ma Xiao-ning He Wan-tong Si Yue-Mao Zheng 《Journal of veterinary science (Suw?n-si, Korea)》2016,17(2):145-152
Previous studies have established a bovine mammary gland epithelia cells in vitro model by the adenovirus-mediated telomerase (hTERT-bMGEs). The present study was conducted to confirm whether hTERT-bMGEs were effective target cells to improve the efficiency of transgenic expression and somatic cell nuclear transfer (SCNT). To accomplish this, a mammary-specific vector encoding human lysozyme and green fluorescent protein was used to verify the transgenic efficiency of hTERT-bMGEs, and untreated bovine mammary gland epithelial cells (bMGEs) were used as a control group. The results showed that the hTERT-bMGEs group had much higher transgenic efficiency and protein expression than the bMGEs group. Furthermore, the nontransgenic and transgenic hTERT-bMGEs were used as donor cells to evaluate the efficiency of SCNT. There were no significant differences in rates of cleavage or blastocysts or hatched blastocysts of cloned embryos from nontransgenic hTERT-bMGEs at passage 18 and 28 groups (82.8% vs. 81.9%, 28.6% vs. 24.8%, 58.6% vs. 55.3%, respectively) and the transgenic group (80.8%, 26.5% and 53.4%); however, they were significantly higher than the bMGEs group (71.2%, 12.8% and 14.8%), (p < 0.05). We confirmed that hTERT-bMGEs could serve as effective target cells for improving development of somatic cell cloned cattle embryos. 相似文献
33.
The traditional scheduling for vehicle is option in the fixed network. But it can't satisfy the real time environment. The demand of order is changeable and uncertain in real environment. It is convenient for scheduling transforming it into static data, but can't get the advantage on time. This paper proposes a real time vehicle scheduling on the study of traditional scheduling and discusses the model structure and the key technology for the real time system that establishes the base for develop teal time system. 相似文献
34.
联合收获机前进速度模糊控制系统多目标遗传优化 总被引:1,自引:0,他引:1
针对联合收获机前进速度模糊控制系统参数设计具有主观性,导致作业性能不理想的问题,以切纵流联合收获机样机为研究对象,构建联合收获机前进速度模糊控制系统仿真模型,并建立控制性能和收获性能的优化目标函数来衡量联合收获机的作业性能,利用多目标遗传算法对模糊控制系统的隶属函数和输送槽、割台螺旋输送器和切流滚筒对前进速度的影响因子进行优化。通过对优化前后模型仿真对比和两组田间试验数据分析,表明优化后的控制系统在受外界干扰情况下控制性能得到了较好的保持,收获性能在喂入量变化不大情况下,单位平均损失率分别由1.45%和1.26%降至1.12%和1.14%,联合收获机的总体作业性能得到改善。 相似文献
35.
基于冠层温度和土壤墒情的实时监测与灌溉决策系统 总被引:4,自引:0,他引:4
设计了一个可以在线连续监测田间作物冠层温度、环境信息和土壤墒情的实时灌溉决策系统,并将其安装于农田进行了1 a实际运行和观测。系统采用太阳能供电和微处理器进行数据采集和管理,为野外的实际应用提供了保障。系统配置了红外温度、空气温/湿度、土壤水分/水势等传感器,能够及时采集田间全面的同步数据,排除了异地观测所形成的数据误差。采用悬臂式多点采集下垫面红外温度检测方法,可以快速采集更多和更高精度的数据,避免单点测量的人为误差。系统配备的快速锁紧装置,能够根据下垫面作物的生长情况进行传感器位置高度调节,使检测数据更符合田间实际情况。通过运行管理和监测数据分析可见,所监测数据能够很精细的刻画田间作物实际生长状况,可以用于灌区综合灌溉决策,实现田间精量灌溉管理和控制,为灌溉管理的精量化和智能化提供数据支持。 相似文献
36.
37.
银海枣褐斑病的病原鉴定与化学防治 总被引:3,自引:0,他引:3
对广东省新近发现的一种银海枣叶部病害进行了病原鉴定,该病病原为链格孢Alternaria alternata(Fr.)Keissl.以生长速率法和孢子萌发法对该病害进行化学防治试验的结果表明:在参试的11种杀菌剂中,叶斑净和世高的防治效果最好,对病斑扩展的抑制率分别达52.82%和33.62%. 相似文献
38.
LU Feng-zhong YU Hao-qiang LI Si LI Wan-chen ZHANG Zhi-yong FU Feng-ling 《农业科学学报》2020,19(9):2165-2176
Pyrabactin resistance 1-like proteins(PYLs) are direct receptors of abscisic acid(ABA). For the redundant and polymorphic functions, some members of the PYL family interact with components of other signaling pathways. Here, 253 positive colonies from a maize cDNA library were screened as interacting proteins with the members of ZmPYL family. After sequencing and function annotation, 17 of 28 interaction combinations were verified by yeast two-hybrid(Y2 H). The germination potential, taproot length and proline content of a quartet mutant of Arabidopsis PYL genes were significantly deceased comparing to the wild type(WT) under alkaline stress(pH 8.5) and 100 μmol L–1 methyl jasmonate(MeJA) induction. The malondialdehyde(MDA) content was significantly increased. After germinating in darkness, the characteristics of dark morphogenesis of the quartet mutant seedlings were more obvious than those of the WT. The differential expression of the related genes of photomorphogenesis in the mutant was much more than that in the WT. Three light and two JA responsive cis-affecting elements were identified during the promoter sequences of the AtPYL1 and AtPYL2 genes. These results suggested that functional polymorphism has evolved among the members of ZmPYL family. In response to developmental and environmental stimuli, they not only function as direct ABA receptors but also interact with components of other signaling pathways mediated JA, brassinosteroid(BR), auxin, etc., and even directly regulate downstream stress-related proteins. These signaling pathways can interact at various crosstalk points and different levels of gene expression within a sophisticated network. 相似文献
39.
为明确水地强筋冬小麦高产、优质、高效的灌溉技术,试验设3个灌水时期8个灌溉处理[越冬期灌1水(W1),拔节期灌1水(W2),孕穗期灌1水(W3),越冬期和拔节期灌2水(W12),越冬期和孕穗期灌2水(W13),拔节期和孕穗期灌2水(W23),越冬期、拔节期和孕穗期灌3水(W123),全生育期不灌水处理(CK)],于小麦成熟期测定籽粒产量、总蛋白及其组分含量和淀粉含量。结果表明,与不灌水的CK比较,所有灌水处理的籽粒产量、有效穗数、穗粒数、千粒重、蛋白质产量以及籽粒淀粉含量均显著增加,但籽粒的总蛋白及其组分含量均呈不同程度降低(W1处理除外)。越冬期灌水对有效穗数、籽粒产量、总蛋白及其组分含量、淀粉含量的提升作用较大;拔节期灌水对穗粒数的提升作用较大,但对淀粉含量的提升作用较小,对总蛋白及其组分含量的降低作用较大;孕穗期灌水对千粒重的提升作用较大,对蛋白质产量的提升作用较小。随着灌水次数增加,小麦籽粒产量显著提高,淀粉含量先显著提高后基本不变,而籽粒总蛋白及其组分含量降低。W123处理籽粒产量最高,其次是W13处理;W1处理籽粒蛋白质及其组分含量最高,其次是W12及W13处理;W23处理淀粉含量最高,其次是W12或W13处理。综合各项指标,最好的灌水组合是越冬期和孕穗期灌2水(W13)。 相似文献
40.