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91.
利用表面增强拉曼光谱(SERS)法结合自适应迭代重加权惩罚最小二乘法(air-PLS)快速检测鸭肉中的螺旋霉素残留。首先采用OTR202作为SERS活性基底,确定了螺旋霉素的1 622 cm-1峰可以作为其在鸭肉提取液中残留检测的拉曼特征峰;然后,通过单因素分析法确定了实验的最佳条件,并在该条件下建立了螺旋霉素浓度范围介于4.0~50.0 mg/L之间的鸭肉提取液加标样本的标准曲线,并获得了良好的线性关系且线性回归方程为y=26.681x+1233.5,决定系数R2=0.980 2,最低检测限为4 mg/L,预测样本的平均回收率为73.38%~105.25%。研究表明,采用SERS技术可以实现鸭肉中螺旋霉素残留的快速检测。 相似文献
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93.
Measuring Fate and Rate of Single‐Molecule Competition of Amplification and Restriction Digestion,and Its Use for Rapid Genotyping Tested with Hepatitis C Viral RNA
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94.
用硫脲标记乙肝抗体(抗-HBs),基于抗原.抗体高选择性识别,建立了非竞争性毛细管电泳免疫分析乙肝表面抗原的新方法。研究了混合温育时间、缓冲溶液酸度和浓度、进样时间的影响。在5mmol/L Tris-20mmol/L H3BO3-3mmol/L EDTA(pH7.0)的运行缓冲溶液中,游离的标记抗体和抗原抗体复合物在15min内完全分离。HBsAg在4.0—50mg/L范围内与复合物的峰面积呈良好的线性关系;相对标准偏差小于6%;检出限为3.0mg/L。该方法用于乙肝病人血清和正常人血清中HBsAg的测定,结果令人满意。 相似文献
95.
溶胶-凝胶非标记免疫传感器检测乙肝表面抗原 总被引:5,自引:0,他引:5
采用溶胶 凝胶 (sol gel)技术包埋乙肝表面抗体 (HBsAb) ,涂布于金盘电极表面 ,构成sol gel HBsAb/Au非标记免疫传感器 ,用于检测人血清中乙肝表面抗原 (HBsAg)。该传感器对HBsAg的电位响应遵循Nernst方程 ,在 1~ 330 μg/L浓度范围内 ,传感器的电位响应值ΔE与HBsAg浓度C的对数呈线性关系 ,线性回归方程为ΔE =1 8.1 7+79.84lgC。响应时间为 3min。癌胚抗原、甲胎蛋白等对测定无明显影响。对于HBsAg阴性血清 ,电位响应值ΔE <30mV ,而对于阳性血清则ΔE >30mV ,据此 ,作为临床判别的依据。对1 0 0例临床血清分别用传感器和酶联免疫法 (ELISA)进行双盲检验 ,两法的符合率为 86 %。 相似文献
96.
Pedro Carmona Marina Molina Arantxa Rodríguez‐Casado 《Journal of Raman spectroscopy : JRS》2009,40(8):893-897
We have employed Raman spectroscopy to investigate the conformation of an (Hepatitis C virus) HCV RNA 25mer (1–25 nucleotides) in solution. The principal findings of this study are (1) the A‐form secondary structure involving C3′‐ endo/anti ribofuranose pucker is predominant; (2) some uridine and guanosine nucleoside residues adopt the C2′‐ endo/anti and C3′‐ endo/syn conformations, respectively, which appear in looped nucleotide sequences; and (3) six out of nine guanine residues are base‐paired probably forming a stem. These results are interpreted as formation of a hairpin whose secondary structure is consistent with that proposed on the basis of phylogenetic comparisons with other viral RNAs. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
97.
Kazuya Ogawa Takayuki Hishiki Yuko Shimizu Kenji Funami Kazuo Sugiyama Yusuke Miyanari Kunitada Shimotohno 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2009,85(7):217-228
Hepatitis C virus (HCV) establishes a persistent infection and causes chronic hepatitis. Chronic hepatitis patients often develop hepatic cirrhosis and progress to liver cancer. The development of this pathological condition is linked to the persistent infection of the virus. In other words, viral replication/multiplication may contribute to disease pathology. Accumulating clinical studies suggest that HCV infection alters lipid metabolism, and thus causes fatty liver. It has been reported that this abnormal metabolism exacerbates hepatic diseases. Recently, we revealed that lipid droplets play a key role in HCV replication. Understanding the molecular mechanism of HCV replication will help elucidate the pathogenic mechanism and develop preventive measures that inhibit disease manifestation by blocking persistent infection. In this review, we outline recent findings on the function of lipid droplets in the HCV replication cycle and describe the relationship between the development of liver diseases and virus replication. 相似文献
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99.
We consider the system of ordinary differential equations x = f(x,y), y = g(x,y), where x 2, y , 0 < 1, and f,g C. It is assumed that the equation g = 0 determines two different smooth surfaces y = (x) and y = (x) intersecting generically along a curve l. It is further assumed that the trajectories of the corresponding degenerate system lying on the surface y = (x) are ducks, i.e., as time increases, they intersect the curve l generically and pass from the stable part {y =(x),g'y < 0} of this surface to the unstable part {y =(x),g'y > 0}. We seek a solution of the so-called duck survival problem, i.e., give an answer to the following question: what trajectories from the one-parameter family of duck trajectories for = 0 are the limits as 0 of some trajectories of the original system. 相似文献
100.
The transfection of NIH 3T3 cells was performed with DNAs from 2 duck primary hepatic carcinomas (DHC 40K, 9K) and I tumor-adjacent liver tissue (TAL, 9N). Transfectants were found from 40K, 9K and 9N DNAs. The secondary transfectants were obtained after transfection of RAT-1 cells with DNAs from primary transfectants. After hybridization with Ha-ras, Ki-ras, N-ras and mht oncogenes, it was found that duck mht (5.2 and 3.2 kb EcoRI fragments) and duck Ha-ras (3.4 kb EcoRI fragments) were present in all these transformants.This is the first report on transforming genes in duck primary hepatic cancer as well as tumoradjacent liver tissue 相似文献