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Biomedical subjects

Hanxi Shen

Publications and source records attributed to Hanxi Shen.

3 recordsLinked to original sources

Studies on the oxidation reaction of tyrosine (Tyr) with H2O2 catalyzed by horseradish peroxidase (HRP) in alcohol-water medium by spectrofluorimetry and differential spectrophotometry.

An oxidation reaction of tyrosine (Tyr) with H(2)O(2) catalyzed by horseradish peroxidase (HRP) was studied by spectrofluorimetry and differential spectrophotometry in the alcohol(methanol, ethanol, 1-propanol and isopropanol)-water mutual solubility system. Compared with the enzymatic-catalyzed reaction in the water medium, the fluorescence intensities of the product weakened, even extinguished. Because the addition of alcohols made the conformation of HRP change, the catalytic reaction shifted to the side of polymerization and the polymer (A(n)H(2), n>or=3) exhibited no fluorescence. The four alcohols cannot deactivate HRP. Moreover isopropanol activated HRP remarkably.

Alcohols↗

PCR hot-start using duplex primers.

A new technique of PCR hot-start using duplex primers has been developed which can decrease the undesirable products arising throughout PCR amplification thereby giving better results than a manual hot-start method.

Biotechnology↗

Real-time quantitative assay of telomerase activity using the duplex scorpion primer.

A novel real-time quantitative method for measuring telomerase activity is described in which the duplex scorpion primer is used to provide an intramolecular probing mechanism for specific detection of telomerase activity. Using this method, linearity from 10 to 10(4) cells expressing telomerase activity could be obtained (R2 = 0.994). The requirement of post-PCR steps is thus obviated.

Biomarkers, Tumor↗