• Biomedical Science Letters
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• v.2 no.2
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• pp.241-247
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• 1996

Poor yields of amplified DNAs could be resulted in polymerase chain reaction(PCR) processes with G+C-rich DNA primers because of their high $T_m$ values. To maximize the yields of amplification in PCR processes with G+C-rich primers, we compared the yields of amplified DNA fragments according to the concentrations of specific denaturants added to the reaction mixture of PCR system. With addition of the mixture of 2.5% glycerol and 1.25% formamide, or 2.5% dimethyl sulfoxide to the reaction cocktail, respectively, remarkable increases in the yields of amplified DNA fragments were not observed in the PCR systems with G+C-low primers of Lyl chromosomal gene from Borrelia burgdorferi but observed in the PCR system with G+C- ich primers of Is900 gene from Mycobacterium parahberculosis. Although we were not practically able to discriminate the yields of PCR DNAs according to the concentrations used in this study, addition of the mixture of 5% glycerol and 2.5% formamide, or 5% DMSO tended to increase the production of extra bands.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1993.05a
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• pp.87-87
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• 1993

Polymerase chain reaction is widely used as a powerful tool in modern molecular biology. As there is agreement that the HPV is an important factor in the head and neck cancers, the detection of HPV DNA sequence in the head and neck cancer tissue has been tried in several ways. We used the PCR to detect the E1 open reading frames of the HPV in paraffin-embedded tissue of the patients with the head neck cancers. Eleven of the fifty-four tested samples (30%) showed positive result. We have analysed the clinical courses and characteristics related with Human Papillomavirus in those patients.

• 연구논문집
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• s.33
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• pp.17-25
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• 2003

In this work, thermal design of a PCR chip for LOC is systematically conducted. From the numerical simulation of a PCR chip based on the finite volume method, how to control the average temperature of a PCR chip and the temperature difference between the denaturation zone and the annealing zone is presented. The average temperature is shown to be controlled by adjusting heat input and a cooler as well as a heater is shown to be necessary to obtain three individual temperature zones for polymerase chain reaction. To reduce the time required, a heat sink for the cooler is not included in the calculation domain for the PCR chip and heat sink design is conducted separately by using a compact modeling method, the porous medium approach.

• Biomedical Science Letters
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• v.5 no.1
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• pp.95-100
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• 1999

It is generally difficult, time-consuming, and expensive for the clinical laboratory to detect vancomycin resistant enterococci (VRE). The aim of this study was to develop and evaluate the multiplex polymerase chain reaction (PCR) assay system as a diagnostic tool for the rapid detection of VRE from clinical samples and/or for the identification of VRE from the bacterial strains isolated from clinical specimens. Specific primers, designed from the nucleotide sequences respectively encoding the vanA, vanB, vanC-1, vanC-2/3 genes in enterococci, were coupled in a multiplex PCR assay system. With this multiplex PCR assay system, we investigated the incidence rates and types of VRE isolated from clinical samples. A total of 75 strains of enterococci were isolated in 3 general hospitals in Korea. Of these isolates, 36 strains showed a pattern of high-level vancomycin resistance which associated with vanA gene, whereas 18 strains showed low-level vancomycin resistance associated with vanC-1 or vanC-2/3 gene. Thus, multiplex PCR assay method established in this study could be applied for the rapid detection of VRE.

• 보건세계
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• v.38 no.1 s.413
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• pp.6-9
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• 1991

• 보건세계
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• v.37 no.12 s.412
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• pp.7-9
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• 1990

• Korean Journal of Microbiology
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• v.43 no.1
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• pp.1-6
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• 2007

We describe a multiplex PCR method that can detect and differentiate simultaneously four different kinds of DNA viruses, Epstein-Barr virus (EBV), cytomegalovirus (CMV), hepatitis B virus (HBV) and parvovirus B19 (B19). Primers for the multiplex PCR reaction were designed to amplify specific regions of the EBV (pol), CMV (pol), HBV (pol) and B19 (ns) viral genomes and used to simultaneously detect individual viruses. In order to achieve optimal sensitivity and specificity for multiplex PCR, the thermo-cycling parameters, primer sequences, and concentration of each reaction components were optimized systematically. The sensitivity of the detection method ranged between 5 and 10 copies of viral genome with a mixture of multiple primer pairs. Furthermore, this highly sensitive test showed no cross-reactivity among the four viruses. Thus, the results obtained in this study provide evidence that the assay system is a good tool for supporting the diagnosis of viral infection and contamination.

• Korean Journal of Microbiology
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• v.40 no.2
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• pp.167-171
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• 2004

Reduction in the leakage of the amplified PCR product out of cell is required for effective in situ PCR. For this purpose, primers with complementary tail sequences at their 5' sides were utilized to synthesize high molecular weight PCR products, but it is time-consuming and causes deterioration of cellular appearance with many PCR cycles. Therefore, it is required to optimize the PCR condition with minimal PCR cycles. To achieve the pur-pose, primer polymers were made without the target DNA in tube from nonspecific amplification with tailed primers and treated onto the fixed Molt/LAV cells on the glass slide for the 20 cycle-in situ PCR, in which the appropriate target signals were observed for the possible use of primer polymers in in situ PCR.

• Tuberculosis and Respiratory Diseases
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• v.45 no.5
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• pp.935-941
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• 1998

Background: As living and dead Mycobacteria could be amplified by polymerase chain reaction(PCR), it was considered that PCR was inappropriate for the monitoring of pulmonary tuberculosis after treatment. But we found negative conversion of PCR after successful treatment. We would like to know about the negative conversion rate of PCR and its conversion time after antituberculous treatment. Methods: We collected 113 sputums from the 16 patients of pulmonary tuberculsosis visiting Catholic University Hospital of Taegu Hyosung. We consecutively tested AFB smear, AFB culture and PCR by 2 to 4 weeks after antituberculous therapy. The patients were classified according to the chest X ray findings. Results: We detected negative conversion of PCR from all 16 patients of the pulmonary tuberculosis within 30 weeks after treatment. The average negative conversion time was $16{\pm}8$ weeks. The conversion time according to the chest X -ray findings were as follows : For the 8 cases of minimum were $9{\pm}5$ weeks, 4 cases of modreate advanced were $20{\pm}8$ weeks, and 4 cases of far advanced were $23{\pm}2$ weeks. The product of PCR was gradually decreased according to the duration of treatment. Conclusions: From the results of our study, we could utilize M. tubercuosis PCR for the prediction of therapy response and monitoring of the patient with pulmonary tuberculosis after treatment.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.4
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• pp.36-43
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• 2011

The forward collision of vehicles in high speed can cause a chain collisions and high fatality rate. Most of the forward collisions are caused by insufficient braking distance due to detection time of driver and safe distance. Also, accumulated detection time of driver is cause of chain collisions after the forward collision. The FVCWS prevents the forward collision by maintaining the safety distance inter-vehicle and reducing detection time of driver. However the FVCWS can cause chain collisions because the system that interacts only forward vehicle has accumulated detection time of driver. In this paper, we analyze forward and chain collisions of normal vehicles and FVCWS vehicles on static traveling scenario. And then, we analyze and compare V2V based FVCWS with them after explaining the system. The V2V FVCWS reduces detection time of driver alike FVCWS as well as remove accumulated detection time of driver by broadcasting emergence message to backward vehicles at the same time. Therefore, the system decrease possibility of forward and chain collisions. All backward normal vehicles and 3~4 backward FVCWS vehicles have possibility of forward and chain collisions in result of analysis. However V2V FVCWS vehicles almost do not chain collisions in the result.