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51.
《教育教学论坛》2019,(50)
文章探讨了siRNA干扰DNALI1基因对HEK-293细胞增殖、迁移的影响。通过培养HEK-293细胞株,分别转染siRNA DNALI1组(DNALI1-homo-66组、DNALI1-homo-426组与DNALI1-homo-777组)和对照组。siRNA DNALI1组细胞中DNALI1 mRNA表达量均低于对照组,三个干扰组中DNALI1-homo-66组干扰效率最高,差异均具有统计学意义(P<0.05);与阳性对照组和阴性对照组相比,siRNA DNALI1组细胞转染24—48h细胞增殖能力明显减弱,差异均具有统计学意义(P<0.05)。在细胞水平可通过RNA干扰特异性抑制DNALI1基因来抑制细胞的增殖和迁移能力,为研究DNALI1基因在细胞中的作用机制奠定了基础。 相似文献
52.
An Inexpensive Gel Electrophoresis-Based Polymerase Chain Reaction Method for Quantifying mRNA Levels 
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下载免费PDF全文 William D. Bradford Laty Cahoon Sara R. Freel Laura L. Mays Hoopes Todd T. Eckdahl 《CBE life sciences education》2005,4(2):157-168
In order to engage their students in a core methodology of the new genomics era, an ever-increasing number of faculty at primarily undergraduate institutions are gaining access to microarray technology. Their students are conducting successful microarray experiments designed to address a variety of interesting questions. A next step in these teaching and research laboratory projects is often validation of the microarray data for individual selected genes. In the research community, this usually involves the use of real-time polymerase chain reaction (PCR), a technology that requires instrumentation and reagents that are prohibitively expensive for most undergraduate institutions. The results of a survey of faculty teaching undergraduates in classroom and research settings indicate a clear need for an alternative approach. We sought to develop an inexpensive and student-friendly gel electrophoresis-based PCR method for quantifying messenger RNA (mRNA) levels using undergraduate researchers as models for students in teaching and research laboratories. We compared the results for three selected genes measured by microarray analysis, real-time PCR, and the gel electrophoresis-based method. The data support the use of the gel electrophoresis-based method as an inexpensive, convenient, yet reliable alternative for quantifying mRNA levels in undergraduate laboratories. 相似文献
53.
Kim-seng Chia Herlina Abdul Rahim Ruzairi Abdul Rahim 《Journal of Zhejiang University. Science. B》2012,13(2):145-151
Visible and near infrared spectroscopy is a non-destructive, green, and rapid technology that can be utilized to estimate
the components of interest without conditioning it, as compared with classical analytical methods. The objective of this paper
is to compare the performance of artificial neural network (ANN) (a nonlinear model) and principal component regression (PCR)
(a linear model) based on visible and shortwave near infrared (VIS-SWNIR) (400–1000 nm) spectra in the non-destructive soluble
solids content measurement of an apple. First, we used multiplicative scattering correction to pre-process the spectral data.
Second, PCR was applied to estimate the optimal number of input variables. Third, the input variables with an optimal amount
were used as the inputs of both multiple linear regression and ANN models. The initial weights and the number of hidden neurons
were adjusted to optimize the performance of ANN. Findings suggest that the predictive performance of ANN with two hidden
neurons outperforms that of PCR. 相似文献
54.
利用RT-PCR技术从日本对虾中克隆到β-actin基因的cDNA,通过双酶切将其克隆到原核表达载体pGEX-4T-2中,转化大肠杆菌E.coli BL21感受态细胞,获得阳性克隆.4℃下IPTG诱导表达,Glutathione Sepharose 4B纯化后获得高纯度的β-actin蛋白.① 相似文献
55.
肠道菌群结构多样性初筛研究 总被引：1，自引：0，他引：1
目的：探讨研究肠道菌群结构的初筛方法,为进行有效、高质量的高通量测序奠定基础.方法：用粪便采样器采集健康儿童粪便进行粪便标本预处理后,采用酚—氯仿方法提取样本菌群基因组DNA,并进行16S rDNAV3区片段PCR扩增,扩增产物用变性梯度凝胶电泳法（denaturing gradient gel electrophoresis,DGGE）检测分析.结果：采用该方法成功地扩增出16S rDNA V3区230bp的片段,经DGGE的方法可以比较出不同儿童粪便样本菌群结构的不同.结论：基于16S rDNA V3区的PCR-DGGE技术能够应用于研究肠道微生物多样性,对于肠道微生物的研究起到了初筛的作用. 相似文献
56.
为建立快速诊断小鹅瘟的PCR方法,根据已发表的GPV主要结构蛋白VP3基因序列,经多序列比对和Oligo6．0软件分析设计特异性PCR引物。以微量法提取病鹅肝组织DNA,优化PCR反应引物退火温度、循环次数和鉴定其特异性,并与酚氯仿法和煮沸法进行同步对比研究。结果显示,建立的PCR检测方法能够特异性检测病鹅肝组织中GPV的核酸,其扩增片段大小为343bp,最佳退火温度为58℃,最佳循环次数为35次。微量法提取的病毒核酸PCR检测灵敏度分别是酚氯仿法的50倍和煮沸法的2500倍。该PCR检测方法不与鹅副黏病毒、禽流感病毒、传染性支气管炎病毒、鸭瘟病毒以及健康鹅肝组织发生交叉反应。本研究建立的GPVPCR检测方法能够快速诊断小鹅瘟。 相似文献
57.
研究禽肉储存过程中菌群的变化,为其长期贮存奠定理论基础.采用酚氯仿异戊醇法提取禽肉中菌群基因组DNA,并通过PCR扩增及DGGE电泳技术探讨其随保存时间延长,菌群结构变化情况.结果表明,成功扩增了菌群基因组DNA,为230bp.DGGE电泳结果发现,DGGE分子指纹图谱上条带存在显著的差异,用bionumberics软件分析DGGE结果,发现第一天和第二天样本的相似度最高为0.75,第三天与第一天相比,相似度为0.47,第四天与第三天相比,相似度又下降为0.16,表明禽肉在储存过程中不断有新的菌种出现,但是具体是什么菌种有待于高通量测序分析. 相似文献
58.
Jafar T Agrawal S Mahdi AA Sharma RK Awasthi S Agarwal GG 《Indian journal of clinical biochemistry : IJCB》2011,26(3):296-302
The pathogenesis of idiopathic nephrotic syndrome is not completely understood. We postulate that cytokine gene polymorphisms
may influence susceptibility or clinical course in Idiopathic Nephrotic Syndrome. Polymorphisms of IL-4, IL-6, and TNF-α cytokines
were investigated in 150 children with Idiopathic Nephrotic Syndrome and 569 healthy controls by using polymerase chain reaction
and restriction fragment length polymorphism. On comparing patient with controls strong association were found for IL-6, TNF-α
and IL-4 at allelic level (IL-6-G174C (G vs. C): P = <0.001; OR = 6.33, TNF-α-G308A (G vs. A): P = <0.001; OR = 1.99, IL-4-C590T (C vs. T): P = 0.048; OR = 1.38). Further when SR group was compared with SS group significant association was found at genotypic level
in all the studied genetic polymorphisms. Studied cytokine gene polymorphisms may influence susceptibility to idiopathic nephrotic
syndrome and might affect steroid response in INS patients. 相似文献
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Liu ZY Huang JF Shi JJ Tao RX Zhou W Zhang LL 《Journal of Zhejiang University. Science. B》2007,8(10):738-744
Detecting plant health conditions plays a key role in farm pest management and crop protection. In this study, measurement of hyperspectral leaf reflectance in rice crop (Oryzasativa L.) was conducted on groups of healthy and infected leaves by the fungus Bipolaris oryzae (Helminthosporium oryzae Breda. de Hann) through the wavelength range from 350 to 2 500 nm. The percentage of leaf surface lesions was estimated and defined as the disease severity. Statistical methods like multiple stepwise regression, principal component analysis and partial least-square regression were utilized to calculate and estimate the disease severity of rice brown spot at the leaf level. Our results revealed that multiple stepwise linear regressions could efficiently estimate disease severity with three wavebands in seven steps. The root mean square errors (RMSEs) for training (n=210) and testing (n=53) dataset were 6.5% and 5.8%, respectively. Principal component analysis showed that the first principal component could explain approximately 80% of the variance of the original hyperspectral reflectance. The regression model with the first two principal components predicted a disease severity with RMSEs of 16.3% and 13.9% for the training and testing dataset, respec-tively. Partial least-square regression with seven extracted factors could most effectively predict disease severity compared with other statistical methods with RMSEs of 4.1% and 2.0% for the training and testing dataset, respectively. Our research demon-strates that it is feasible to estimate the disease severity of rice brown spot using hyperspectral reflectance data at the leaf level. 相似文献