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61.
分离纯化小鼠胸腺上皮细胞(mTEC),以DMEM、DMEM/F12、RPMI 1640 3种基础培养液加10%胎牛血清完全培养液进行培养, MTT法和流式细胞术分别检测mTEC的增殖及细胞周期,筛选出最适合mTEC生长的培养液。结果表明,DMEM培养的mTEC增殖快,细胞增殖指数明显高于DMEM/F12、RPMI 1640培养液,表明DMEM是mTEC体外培养的最佳培养液。  相似文献   
62.
应用HPLC方法检测了96头30日龄荣昌猪仔猪(公、母各半)耳组织全基因组DNA的甲基化程度,探讨性别间DNA甲基化水平的差异。结果表明:仔公猪、仔母猪的DNA甲基化含量分别为4.296%和3.902%,在统计上无显著差异(P0.05)。研究结果证实,性别不是影响荣昌猪仔猪DNA甲基化状态的主要因素。  相似文献   
63.
蚕蛹油微胶囊的制备   总被引:3,自引:0,他引:3  
为了改善蚕蛹油的加工性能和延长其保质期,以大豆蛋白和β-环状糊精为壁材,采用喷雾干燥法制备蚕蛹油微胶囊。依据蚕蛹油微胶囊乳状液的稳定性检测指标,确定壁材大豆蛋白和β-环状糊精的质量比为1∶1。通过正交试验确定制备蚕蛹油微胶囊的最佳工艺条件为:芯材(蚕蛹油)与壁材的质量比为1∶2,乳状液中固形物的质量分数为20%,均质压力25MPa,喷雾干燥的进风温度190℃。在此工艺条件下制备蚕蛹油微胶囊的包埋率为91.2%。  相似文献   
64.
The sperm‐mediated gene transfer method is applicable to transgenesis in many species that use spermatozoa for reproduction recently, which has been shown various results. In the current study, we show that transgenic porcine embryos can be efficiently produced by employing a simple transfection method that uses magnetic nanoparticles (MNPs). The complexes formed between plasmid DNA and MNPs were bounded on ejaculated boar spermatozoa at a higher efficiency compared to methods using DNA alone or lipofection. Using confocal microscopy, rhodamine fluorophore‐labelled MNPs were detected on external surfaces of the spermatozoa membrane, which were bounded on zona pellucida of in vitro maturated oocyte during in vitro fertilization. Electron microscopy revealed that clusters of MNPs were detected in inside of plasma membrane and nucleus of the spermatozoa head. Additionally, we found that magnetofected boar spermatozoa could be fertilized with oocytes in vitro and that the resulting gene of green fluorescent protein was detected in fertilized eggs by genomic PCR analysis. Taken together, these results suggest that MNPs can be used to efficiently introduce a transgene into embryo via spermatozoa.  相似文献   
65.
The aim of this study was to investigate the expression and biological characteristics of adiponectin (ADIPOQ) gene in longissimus dorsi muscle of Hanper sheep at different months of age.The ADIPOQ gene mRNA expression was detected in longissimus dorsi muscle of Hanper sheep at 3 different growth periods (1,7 and 13 months old) by Real-time quantitative PCR.The bioinformatics method was used to analyze the nucleotide and amino acid sequences of ADIPOQ gene,protein characteristics and network interaction protein.The results showed that ADIPOQ gene was expressed in longissimus dorsi muscle of Hanper sheep,which showed an increasing trend with the growth of the months age without significant difference (P>0.05).There was higher homology of ADIPOQ gene with Capra hircus (98.60%,99.00%) and Bos taurus (98.60%,87.00%) in nucleotide and amino acid sequences.The results of physical and chemical properties analysis showed that the molecular formula of ADIPOQ protein was C1172H1776N314O349S5,the molecular mass was 26.00 ku,and the theoretical isoelectric point (pI) was 5.88,which suggested that the protein was acidic.The average value of ADIPOQ hydrophilic protein (GRAVY) was -0.403,which indicated that the protein was hydrophilic and didn’t belong to transmembrane protein.In addition,the signal peptide sequence was Met1-Ala17,and the cleavage site was between Ala17 and Arg18.ADIPOQ existed collagen structure domain and C1Q conserved structure domain at position 45-101 and 101-237,respectively.The secondary structure mainly composed of random coil (66.95%).The construction of protein interaction network indicated that ADIPOQ might interact with ADIPOR1,ADIPOR2,CDH13 and LEP.The results provided a theoretical basis for further exploring the molecular biological functions of ADIPOQ gene in the process of muscle development in Hanper sheep.  相似文献   
66.
应用光镜和实时定量PCR技术研究了Ghrelin对雌激素诱导小鼠胸腺萎缩过程中胸腺形态学以及部分细胞因子和凋亡相关蛋白基因表达的影响。结果显示,注射Ghrelin后,雌激素诱导的小鼠萎缩胸腺在形态学上基本恢复到正常水平,胸腺中IL-6、TGF-[31、Caspase3、FADDmRNA含量显著降低,Caspase9、FasLmRNA含量略为下降,而IL-7、Bcl-2mRNA含量有所上升。结果表明,Ghrelin可能通过促进胸腺上皮细胞的增殖以及阻断Caspase级联程序和Fas/FasL凋亡信号通路抑制胸腺细胞的凋亡,从而逆转雌激素诱导的小鼠胸腺萎缩。  相似文献   
67.
为探讨重组鸡白介素18(mChIL-18)毕赤酵母工程菌在5L发酵罐中大规模发酵的工艺及其对新城疫疫苗的免疫增强作用,复苏工程菌GS115/pPIC9K-mChIL-18于YPD培养基,在其D600值达到5.2左右时转入发酵罐中,采用分批补料方式对毕赤酵母工程菌进行高密度发酵。控制和优化各种发酵条件,经历84h结束发酵。将发酵液离心,用6×His镍柱对上清中的表达产物进行纯化,并将纯化后的mChIL-18用脂质体包被后和新城疫疫苗一起对鸡群免疫。结果显示,毕赤酵母工程菌在5L发酵罐采用甲醇诱导补料批式发酵,在pH5.5,溶氧值20%~30%,温度28℃,诱导72h,mChIL-18的表达产量为560mg/L,发酵上清经纯化后纯度可达70%以上;用0.2mL的mChIL-18脂质体能够显著增强机体的免疫力,其中HI抗体效价和淋巴细胞亚群CD4+、CD8+含量均显著高于对照组。这表明mChIL-18毕赤酵母工程菌在5L发酵罐高密度发酵成功,并能显著增强新城疫疫苗的免疫效果,为IL-18在生产实践得到更好的应用奠定了基础。  相似文献   
68.
The purpose of this study was to assess the effects of four anesthetic protocols on normal canine brain uptake of 2‐deoxy‐2‐[18F]fluoro‐d ‐glucose (FDG) using positron emission tomography/computed tomography (PET/CT). Five clinically normal beagle dogs were anesthetized with (1) propofol/isoflurane, (2) medetomidine/pentobarbital, (3) xylazine/ketamine, and (4) medetomidine/tiletamine–zolazepam in a randomized cross‐over design. The standard uptake value (SUV) of FDG was obtained in the frontal, parietal, temporal and occipital lobes, cerebellum, brainstem and whole brain, and compared within and between anesthetic protocols using the Friedman test with significance set at P<0.05. Significant differences in SUVs were observed in various part of the brain associated with each anesthetic protocol. The SUV for the frontal and occipital lobes was significantly higher than in the brainstem in all dogs. Dogs receiving medetomidine/tiletamine–zolazepam also had significantly higher whole brain SUVs than the propofol/isoflurane group. We concluded that each anesthetic protocol exerted a different regional brain glucose uptake pattern. As a result, when comparing brain glucose uptake using PET/CT, one should consider the effects of anesthetic protocols on different regions of the glucose uptake in the dog's brain.  相似文献   
69.
基于前海蛇口自贸区动植物检疫工作的现状和需求,对自贸区动植检快筛实验室的建设要素进行了分析和探讨,提出了以快筛快检、生物安全监测和技术交流平台为主要功能,建立自贸区动植检快筛实验室,并在实验室的建立标准、质量控制和生物安全等方面提出了初步建议,以期为自贸区动植检快筛实验室的建设提供借鉴。  相似文献   
70.
1光照对蛋鸡的作用原理光照对鸡的作用有两个方面:①促进生殖腺多种激素的作用;②通过光照周期循环作用使鸡体内所有机能的固有节律与明暗同步。就是说,光照对鸡的作用是同步信号作用和刺激作用。刺激作用的效果表现为开产日龄的控制和产蛋率的变化;而同步信号作用效果则表现为对排卵和产蛋时间的制约。  相似文献   
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