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61.
旨在探讨miR 133c 3p在猪流行腹泻病毒(PEDV)引起的细胞凋亡过程中所起的作用,并探讨其发挥作用的机制.以PEDV感染MARC-145细胞为模型,检测PEDV感染过程中细胞的凋亡情况以及6个与凋亡相关mi-croRNAs的表达差异,RT-qPCR检测PEDV感染过程中与凋亡相关microRNAs的表达差异,合...  相似文献   
62.
Ccr-lncRNA172145靶向miR-206在锦鲤体色调控中的作用初探   总被引:1,自引:0,他引:1  
为了解非编码RNA在锦鲤体色分化变异中的分子调控机制,在课题组前期对锦鲤皮肤组织转录组测序的基础上,筛选到4条在3种皮肤(黑色、红色、白色)组织中显著差异表达的lncRNA;基于RNAhybrid和TargetScan靶基因预测软件,发现lncRNA172145与黑色素合成通路中miR-206之间存在靶向结合位点.借助...  相似文献   
63.
两种麻醉剂对罗非鱼的急性毒性及联合毒性研究   总被引:2,自引:0,他引:2  
根据预试验结果确定最高安全浓度和最低全致死浓度,分别设置5个等对数浓度,进行MS-222和苯唑卡因及其1:1混合药物对罗非鱼(Oreochromis niloticus)的24h和96h毒性试验.结果:MS-222对罗非鱼的24h、96h半致死浓度及95%置信区间分别为88.84 mg/L(86.92~90.81 nag,/L)、76.18 mg/L(73.27~79.21 mg/L);苯唑卡因对罗非鱼的24h、96h半致死浓度及95%置信区间分别为44.49 mg/L(43.76~45.24 mg/L)、22.61 mg/L(20.29~25.20 mg/L);混合药物对罗非鱼的24h、96h半致死浓度及95%置信区间分别为63.35 mg/L(61.00~65.79 mg/L)、30.39 mg/L(29.48~31.34 mg/L).这表明:在同等剂量条件下,苯唑卡因对罗非鱼的毒性比MS-222强;将两种药物等比例混合后,在24h和96h毒性试验中,分别呈现出拮抗作用和协同作用.  相似文献   
64.
The present study determined the effective concentrations of clove oil and MS‐222 in juvenile rohu Labeo rohita for quick induction and recovery. The immune‐biochemical responses due to 0, 1 and 24 hr exposure to those anaesthetics were also evaluated. Of four concentrations of the anaesthetics examined, the lowest effective concentration of clove oil and MS‐222 were 50 µl/L and 125 mg/L respectively. Clove oil and MS‐222 significantly increased the myeloperoxidase, total protein and alkaline phosphatase activity at some of the holding durations. However, superoxide anion production (after 0 and 1 hr) and antiprotease activity (after 24 hr) were significantly reduced in fish exposed to clove oil. Serum glucose content was significantly elevated in the MS‐222‐treated group. Furthermore, the clove oil‐treated group showed significantly higher levels of serum Na+ and K+, while the aspartate and alanine aminotransferase activities were significantly enhanced in the MS‐222 group. The use of both clove oil and MS‐222 is advised as an anaesthetic agent for rohu with a bias towards clove oil, considering its economic and operational feasibility.  相似文献   
65.
Although daily variations in drug pharmacokinetics have been reported for a variety of teleost species, the influence of this daily variation on the cortisol response following anaesthesia remains poorly understood. To address this, two experiments were performed. The first experiment described the daily patterns of cortisol and glucose secretion in tilapia (Oreochromis niloticus). The second experiment investigated how the timing of anaesthetic administration (specifically at mid‐light [ML] or at mid‐dark [MD]) affects the induction and recovery times and plasma cortisol and glucose levels of juvenile Nile tilapia exposed to benzocaine, clove oil or tricaine methanesulphonate (MS‐222). The results revealed that the effect on the stress response associated with the moment when anaesthesia took place (ML or MD) varied according to the treatment (p < 0.05). Cortisol levels were significantly higher at ML for MS‐222 (ML = 116.23 ± 25.55; MD = 48.25 ± 22.33 ng/dl) (p < 0.05) and clove oil (ML 59.73 ± 14.27; MD 38.26 ± 12.07 ng/dl) (p < 0.05), whereas no significant differences were found between ML and MD cortisol levels for the control treatment (ML = 72.91 ± 18.42; MD = 64.80 ± 10.68 ng/dl) (p > 0.05) or in the benzocaine‐treated group (ML = 38.7 ± 4.90; MD = 38.60 ± 3.69 ng/dl) (p > 0.05). The highest plasma cortisol level in ML was found in the MS‐222‐treated group. All the tested anaesthetics had similar cortisol levels at MD (p > 0.05).  相似文献   
66.
基于Illumina Hiseq 4000高通量测序技术筛选得到仔猪感染C型产气荚膜梭菌耐受和易感组中显著上调表达的miR-204。为研究miR-204在各组织中的表达,进一步筛选miR-204参与调控仔猪C型产气荚膜梭菌感染的关键靶基因,采用实时荧光定量PCR方法检测了miR-204在7日龄仔猪各组织中的表达,利用MEGA7.0软件对其成熟体序列保守性进行分析,运用TargetScan、miRDB、PicTar软件进行靶基因预测,并用DAVID软件对靶基因进行Gene Ontology和KEGG Pathway通路富集分析,进一步采用qRT-PCR方法对筛选得到的关键靶基因在猪肠上皮细胞(IPEC-J2)中进行靶向关系验证。结果表明,miR-204在7日龄仔猪肾脏、肝脏、胸腺、淋巴、十二指肠和回肠组织中均高度表达,其成熟体序列在脊椎动物间高度保守。3种软件预测到的共同靶基因有114个,这些靶基因显著(P<0.05)富集在15个GO功能和13个信号通路。结合前期得到的抗性基因,筛选到4个关键靶基因NR3C1、SIRT1、BCL2L2和DLG5,转染miR-204 mimics后,靶基因SIRT1、BCL2L2和DLG5极显著(P<0.01)下调表达。miR-204是参与调控仔猪抵抗C型产气荚膜梭菌感染的重要因子,SIRT1、BCL2L2和DLG5可能是miR-204的关键靶基因,其功能还需进一步验证。  相似文献   
67.
徐建  于鑫  曾芳  童雄  王翀 《兽医大学学报》2012,(9):1260-1265
为了探讨miR-24对猪骨骼肌发育的影响,对体外培养1日龄纯种长白公猪骨骼肌卫星细胞分别转染miR-24过表达载体和干扰片段,发现过表达miR-24后,成肌分化基因MyoD、Myogenin和Myf5表达量显著升高,骨骼肌卫星细胞分化趋势增强;干扰miR-24后,Myogenin的表达量显著降低;同时,靶基因预测结果显示Myogenin可能是miR-24的靶基因。  相似文献   
68.
MS-222、丁香油、苯唑卡因对养殖美洲鲥幼鱼的麻醉效果   总被引:23,自引:0,他引:23  
研究了MS-222、丁香油、苯唑卡因3种麻醉剂对美洲鲥Alosa sapidissima幼鱼的麻醉效果,并运用该3种麻醉剂的适宜剂量对美洲鲥幼鱼进行了运输试验。麻醉试验结果表明:在较高麻醉浓度(MS-222为75 mg/L以上,丁香油为20 mg/L以上,苯唑卡因为40 mg/L以上)下,鱼很快(30 min内)停止鳃盖张合运动,且停止鳃盖运动的鱼在空气中暴露一定时间(10 min内)后也能够复苏;在适宜的麻醉浓度(MS-222为20-30 mg/L,丁香油为8-10 mg/L;苯唑卡因为20-30 mg/L)下,鱼能够进入麻醉状态,且能保持很长时间(12 h);麻醉效果随着水温的升高而增强;在20 mg/L MS-222麻醉剂下,小规格鱼较大规格鱼更容易进入麻醉状态,而在10 mg/L丁香油和20 mg/L苯唑卡因麻醉剂下,小规格鱼却难进入麻醉状态。运输试验结果表明:麻醉运输组和对照组(非麻醉运输组)鱼血清中皮质醇的含量均显著高于基础组(运输前)(P<0.05);麻醉运输后鱼血清中皮质醇的含量虽均有一定程度的升高,但明显低于对照组,其中仅苯唑卡因麻醉运输组鱼血清中皮质醇的含量显著低于对照组(P<0.05)。试验结果表明,苯唑卡因更适合用于运输美洲鲥的麻醉。  相似文献   
69.
AIM: To explore whether miR-21 low expression enhances the effect of matrine (MAT) on the apoptosis of hepatocellular carcinoma cells.METHODS: Real-time fluorescence quantitative PCR (RT-qPCR) was used to detect the expression of miR-21 in the HepG2 cells treated with different concentrations of MAT. The effect of miR-21 on MAT-induced HepG2 cell apoptosis was analyzed by flow cytometry. The mRNA and protein expression of Bcl-2 and Bax in the HepG2 cells treated with MAT was determined by RT-qPCR and Western blot.RESULTS: The expression of miR-21 increased with the increasing concentration of MAT. Low expression of miR-21 promoted MAT-induced apoptosis, and enhanced the expression of Bax at mRNA and protein levels (P<0.05), while inhibited the expression of Bcl-2 at mRNA and protein levels (P<0.05).CONCLUSION: Low expression of miR-21 enhances MAT-induced HepG2 cell apoptosis by inhibiting the expression of Bcl-2 and promoting Bax expression.  相似文献   
70.
试验旨在研究骨骼肌中特异表达miR-133前体在不同绵羊群体中的多态,分析其与绵羊骨骼肌发育表型的相关性。采用PCR-SSCP技术对miR-133前体序列在特克赛尔羊、中国美利奴细毛羊、阿勒泰羊和湖羊四种不同产肉性能的绵羊群体进行了多态性检测,并分析多态性位点对miR-133前体序列二级结构、二级结构稳定性及加工、成熟的影响。结果表明,miR-133前体序列下游194bp(g.54047535)处检测到AG突变,并且该SNP与绵羊的产肉性能存在明显的相关性,在特克赛尔羊中GG是优势基因型,G等位基因频率高达0.86,是中国美利奴细毛羊群体该位点频率的4倍。二级结构的生物信息学预测结果表明,该SNP位点致使miR-133前体的二级结构发生明显改变,自由能值降低3.2kJ/mol。以上结果提示,绵羊miR-133前体序列的SNP(g.54047535)位点可能对miR-133前体的加工成熟具有重要影响,并最终影响绵羊的产肉性能。  相似文献   
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