猪miR-199a-5p对脂质生成的影响及其靶基因的预测和分析

本研究旨在分析miR-199a-5p对猪肌内脂肪细胞脂质生成的影响及作用机制。采集淮南猪不同育肥时期（育肥前期、中期和后期）的背最长肌和皮下脂肪组织,通过实时荧光定量PCR分析其表达变化趋势;合成miR-199a-5p的mimics,转染猪原代肌内脂肪细胞,诱导分化后通过油红O染色观察过表达miR-199a-5p对脂质生成的影响;结合之前筛选到的脂肪型和瘦肉型猪差异表达mRNAs、lncRNAs和circRNAs,使用miRanda软件筛选miR-199a-5p的靶分子,并用GO和KEGG富集分析法对这些mRNAs、lncRNAs的共表达基因和circRNAs的来源基因进行功能分析。结果显示,随着育肥进程,miR-199a-5p在背最长肌中表达量持续上调,而在皮下脂肪组织中表达量先下调后上调;过表达miR-199a-5p可抑制肌内脂肪细胞的脂质生成。共筛选到9个mRNAs、5个lncRNAs和1 258个circRNAs包含miR-199a-5p结合位点,GO分析主要富集于内质网和肌动蛋白结合,KEGG分析发现主要富集于糖、脂质和蛋白质代谢。提示miR-199a-5p可能通过与lncRNAs和circRNAs互作间接调控靶基因,参与调控肌肉发育、脂质生成和代谢,可作为影响肉质性状的候选miRNA。     

限抗背景下副猪嗜血杆菌病的防控

饲料添加抗生素是养殖行业用来控制动物细菌病、促进畜禽生长的常用手段,随着人们公共安全意识的觉醒和提高,减抗、限抗和禁抗已是全世界养殖行业发展的大势所趋,替抗方案正受到越来越多的关注。副猪嗜血杆菌病是一种严重危害养猪业发展的细菌性疾病,且发病率和死亡率近年来逐年上升。随着我国饲料禁抗新政正式落地,副猪嗜血杆菌病势必会以更猛烈的攻势掀起更大的风波。文章主要针对限抗背景下副猪嗜血杆菌病的防治措施进行了总结和分析,旨在为人们合理使用抗生素、选择替抗方案提供参考。     

土默川平原不同玉米品种青贮饲料的品质比较

为筛选出适宜土默川平原用作青贮饲料的玉米品种,以内蒙古土默特左旗5个产量较高的玉米品种为原料,比较其青贮前后营养成分、发酵品质和菌群的变化,并运用灰色关联度分析法进行综合评价。结果表明,5个玉米品种青贮后营养保存较好,品质均有所改善。品种金岭367、京科968和先玉027青贮后的相对饲用价值较高(RFV>140),品种京科968、先玉027和金岭367的干物质含量和水溶性碳水化合物含量较高,是调制青贮饲料的优质原料。青贮后,各品种的粗蛋白含量下降(降幅3.46%~14.4%),但品种间无显著差异;品种京科968、先玉027和金岭367的中性洗涤剂纤维(NDF)和酸性洗涤纤维(ADF)含量较低,饲用价值较高。灰色关联度分析表明,金岭367玉米青贮后综合表现最优。     

玻璃苗中纤维素、木素及元素含量变化的研究

本研究通过＾１４Ｃ－葡萄糖参与珠美海棠玻璃化发生过程中的代谢活动，测定了玻璃苗不同部位的纤维素和木素中的放射性活度，摸清了玻璃苗中纤维素和木素含量的分布状况及变化。利用中子活化分析技术测定了玻璃苗不同部位中的多种元素含量和分布状况及变化。结果表明，玻璃苗中纤维素和木素的合成速度比正常苗降低了１０．３８％，降解速度增加了１８．７６％，造成玻璃苗中纤维素和木素含量下降４３．６８％，玻璃苗不同部位中绝大     

洋港泥石流工程防治探讨

洋港泥石流频繁发生，使该地区自然条件恶化，耕地面积缩减，烘涝灾害频仍，人民生命财产遭受严重损失。自１９８３年正式投入治理以来，有效地防治了重大泥石流灾害的发生，保障了当地工农业生产、交通运输、采矿、水利水电建设的顺利进行。本文主要对洋港泥石流的分布、活动规律、成因、危害、工程防治与效益等问题进行了探讨。     

The use of nitrogen-15 natural abundance and nitrogen yield of non-nodulating isolines to estimate nitrogen fixation by soybeans (Glycine max L.) across three elevations

Summary Dissimilarities in soil N uptake between N₂-fixing and reference non-N₂-fixing plants can lead to inaccurate N₂ fixation estimates by N difference and ¹⁵N enrichment methods. The natural ¹⁵N abundance ( ¹⁵N) method relies on a stabilized soil ¹⁵N pool and may provide reliable estimates of N₂ fixation. Estimates based on the ¹⁵N and differences in N yield of nodulating and non-nodulating isolines of soybean were compared in this study. Five soybeans from maturity groups 00, IV, VI, and VIII and their respective non-nodulating isolines were grown at three elevations differing in ambient temperature and soil N availability. Despite large differences in phenological development and N yield between the non-nodulating isolines, the ¹⁵N values measured on seeds were relatively constant within a site. The ¹⁵N method consistently produced lower N₂ fixation estimates than the N difference method, but only in three of the 15 observations did they differ significantly. The average crop N derived from N₂ fixation across sites and maturity groups was 81% by N difference compared to 71% by ¹⁵N. The magnitude of difference between the two methods increased with increasing proportions of N derived from N₂ fixation. These differences between the two methods were not related to differences in total N across sites or genotypes. The low N₂ fixation estimates based on ¹⁵N might indicate that the nodulating isolines had assimilated more soil N than the non-nodulating ones. A lower variance indicated that the estimates by N difference using non-nodulating isolines were more precise than those by ¹⁵N. Since the differences between the estimates were large only at high N₂ fixation levels (low soil N availability), either method may be used in most situations when a non-nodulating isoline is used as the reference plant. The ¹⁵N method may have a comparative advantage over N difference and ¹⁵N enrichment methods in the absence of a suitable non-N₂-fixing reference plant such as a non-nodulating isoline.     

小麦品种耐湿性鉴定的示踪方法

利用~(32)P、~(14)C同位素示踪技术在淹水条件下测定了孕穗期小麦的根系活力及叶片C_3光合酶RubIscb活性。结果表明,不同品种间,其根系活力和Rubisco活性有显著差异。根据根系活力及叶片光合酶Rubisco活性鉴定小麦品种耐湿性结果与根据主茎绿叶数及产量性状鉴定耐湿性结果是一致的。因此,利用示踪技术评价小麦品种的耐湿性是可行的,且具有灵敏、快速、准确等优点。     

莫莫格湿地土壤氮磷空间分布规律研究

以莫莫格湿地为研究对象 ,研究了氮磷在湿地土壤中的空间分布。结果表明 ,表层土壤全氮、全磷含量显著高于下层土壤 ,土壤全氮的水平变异性较全磷强 ;全氮和全磷的垂直分布总体变化趋势均为由上到下依次减少 ,且都以 5 0 cm处为其变化转折点 ,但全氮的变化较全磷快 ;全磷、全氮含量与土壤有机质、N/ P比极显著相关 ,但p H值对其影响十分微弱。     

Solving the Operation Directing Expert Systems Based on Characteristic Model

In this thesis,aiming at the characteristic of operation directing expert systems,we use the state of process characteristic parameter to describe the process condition(state).We propose a solving strategy batal on characteristic model.According to the solving-tree of process condition (state),the present process state can be obtained. An example of application illustrates that this method solves problem quickly and satisfy the real time directing operation.     

Expression of late maturity α-amylase in wheat containing gibberellic acid insensitivity genes

Summary Two wheat cultivars, Spica and Lerma 52, which consistently produce high levels of -amylase during the later stages of grain development (late maturity -amylase), were crossed with a set of four near-isogenic lines carrying the tall (rht) allele or one of the dwarfing genes Rht1, Rht2 or Rht3 (GA-insensitive alleles). The F₁ and F₂ populations were developed and analysed for grain -amylase and plant height. The Rht3 gene exhibited the strongest influence on plant height and strongly inhibited new -amylase synthesis during the later part of grain ripening. By comparison, Rht1 and Rht2 had a less pronounced effect but still significantly reduced the expression of late maturity -amylase. These observations suggest that gibberellic acid is involved either directly or indirectly in this phenomenon. The implications of the effect of dwarfing genes on expression of late maturity -amylase are discussed in relation to cultivar improvement and to the identification and control of high -amylase germplasm.