• Korean Journal of Clinical Laboratory Science
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• v.38 no.3
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• pp.196-202
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• 2006

Treatment of hepatitis B virus (HBV) with lamivudine is effective in suppressing virus replication and results in reduced inflammatory activity. However the most troublesome problem of lamivudine treatment is the emergence of lamivudine-resistant strains with amino acid substitution in the YMDD motif of DNA polymerase gene during the treatment. The aim of this study was to determine the mutation of YMDD motif (codon 552) and codon 528 in chronic HBV patients with lamivudine therapy using PCR-direct sequencing and to investigate the relationship between lamivudine mediated HBV mutation and HBeAg. HBV DNA was extracted from serum samples of HBV patients and amplified by nested PCR with two sets of primer pairs selected in HBV DNA polymerase gene. Amplified PCR product was analyzed by 2% agarose gel electrophoresis and direct sequencing. HBV mutation was detected in 124 out of 207 samples (60%). Single mutation was 50.8% for M552I, 43.5% for M552V, 5.7% for M552I/V and the L528M mutation was 67.0%. Double mutation was 43.6% for M552V/L528M, 33.1% for M552I/L528(wild type), 17.7% for M552I/L528M and 5.6% for M552I/V/L528M. Serine mutation at YMDD motif (M552S) was not found and the L528M mutation frequently accompanied M552V type. In this study, the typical difference of frequencies for HBV mutation depending on HBeAg was not found. Moreover, the PCR-direct sequencing method used in this study might be a powerful tool for the mutation study in clinical reference laboratories with high volume.

• Tuberculosis and Respiratory Diseases
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• v.56 no.1
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• pp.77-84
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• 2004

Background : We hypothesized that there was a relationship between body weight change and bronchodilator response (BDR) in patients with chronic renal failure (CRF) on hemodialysis (HD). Several mechanisms such as pulmonary edema due to water retention or increased permeability of alveolar capillary may play a important role in pulmonary function impairment and bronchial hyperresponsiveness in patients with CRF on HD. But, no studies have been published concerning BDR in patients with CRF on HD. This study was aimed to know the immediate effect of hemodialysis on pulmonary function and BDR in patients with CRF on HD. Methods : This study included 30 patients with CRF on HD. We collected data including age, sex, height, pretibial and pedal pitting edema, interdialysis weight gain, postdialysis weight loss, underlying diseases, duration of HD, $FEV_1$, FVC, $FEV_1/FVC$, and BDR before and after HD. Results : Interdialysis weight gain of the patients was $3.4{\pm}1.0kg$, and postdialysis weight loss was $3.2{\pm}0.7kg$. Before HD,$FEV_1$, FVC, and $FEV_1/FVC$ of the patients were $89{\pm}22%$, $86{\pm}19%$ of predicted, and $87{\pm}10%$. After bronchodilator inhalation, these parameters were changed to $95{\pm}22%$, $90{\pm}19%$ of predicted, and $88{\pm}9%$ respectively. BDR was positive in 15 patients. After HD, $FEV_1$, FVC, and $FEV_1/FVC$ of the patients were $100{\pm}23%$, $94{\pm}18%$ of predicted, and $88{\pm}11%$. After bronchodilator inhalation, these parameters were changed to $102{\pm}23%$, $96{\pm}18%$ of predicted, and $89{\pm}8%$ respectively. BDR was positive in 9 patients. Conclusion : First, HD increases $FEV_1$, FVC, and $FEV_1/FVC$ but little affects BDR. Second, there is no correlation between postdialysis weight loss and increases in $FEV_1$, FVC, and $FEV_1/FVC$ after HD. Third, there is also no correlation not only between interdialysis weight gain and BDR before HD but between postdialysis weight loss and BDR after HD.

• Tuberculosis and Respiratory Diseases
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• v.56 no.1
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• pp.67-76
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• 2004

Background : Pulmonary hypertension is a poor prognostic factor in patients with chronic respiratory disease. However, diagnosing pulmonary hypertension is a difficult procedure which often requires an invasive test. Thus new alternative biochemical markers would be useful in clinical field and are in search. We sought to assess the role of plasma N-terminal pro-brain natriuretic peptide(NT-proBNP) in patients with pulmonary hypertension. Method : We measured plasma NT-proBNP level in twenty nine patients suspected for pulmonary hypertension. Pulmonary hypertension was defined as being right ventricular systolic pressure more than 35 mm Hg estimated by Doppler echocardiography. Plasma NT-proBNP level was measured by electrochemiluminescence sandwich immunoassay. Results : The log-transformed values for plasma NT-proBNP levels showed a linear correlation (correlation coefficiency: 0.783, p-value <0.001) with right ventricular systolic pressure. Plasma NT-proBNP levels closely correlated with right ventricular systolic pressure, right ventricular hypertrophy, interventricular septal flattening and right ventricular dilatation. Conclusion : Our results suggest that the measurement of plasma NT-proBNP level is an useful marker of the presence of pulmonary hypertension.

• Tuberculosis and Respiratory Diseases
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• v.54 no.5
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• pp.485-494
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• 2003

Background : Most previous studies regarding the role of GSTMl and GSTT1 on lung cancer risk have been focused mainly on male smokers. However, epidemiological characteristics, histologic types and risk factors are different in female and male lung cancers, we investigated the association between these genotypes and lung cancer risk in males and females separately. Materials and Methods : The study population consisted of 253 lung cancer (153 males and 100 females) and 243 controls (140 males and 103 females). GSTM1 and GSTT1 genotypes were determined by a multiplex PCR. Results : In the male population, neither GSTM1 nor GSTT1 null genotype showed significant difference between cases and controls. In the female population, the frequencies of GSTM1 null genotype showed no significant difference between cases and controls. However, the frequencies of GSTT1 null genotype was significantly higher in cases (70.3%) than controls (55.3%, odds ratio (OR)=2.18; 95% confidence interval (CI=l.21-3.93). When the female population was stratified by age and smoking status, the ORs for GSTT1 null genotype were significantly higher in subgroups of ${\leq}60$ years (OR=4.82; 95% CI=l.61-14.4) and never-smokers (OR=4.29; 95% CI=1.94-9.48) but not in subgroups of >60 years or smokers. When stratifying the female never-smokers by age, the ORs for GSTT1 null genotype were significantly higher in both age groups of ${\leq}60$ years (OR=7.64; 95% CI=2.00-29.2) and >60 years (OR=2.89; 95% CI=1.05-7.94). Conclusion : We found that GSTT1 null genotype was associated with an increased risk of lung cancer in Korean female never-smokers. This result suggests that GSTT1 null genotype could be used as a biomarker for genetic susceptibility to lung cancer in Korean female never-smokers.

• Journal of Korean Society of Forest Science
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• v.98 no.1
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• pp.94-105
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• 2009

Black locust (Robinia pseudoacacia) stand is representative lowland exotic plantation with low ecological quality and arrested succession in South Korea. To facilitate succession and restore natural vegetation, small canopy gaps (${\sim}57m^2$), which can modify minimally structural variables and reduce restoration related disturbances on stand, was established in the black locust stand, and oak (Quercus serrata) seedlings were introduced in the gap. Two types of varying levels were introduced for gap creation; cutting (C) and girdling (G) on canopies. Understory removal (CU and GU) treatment was applied as subtypes of structural modification. Growth (diameter, height and leaf area) of target species and responses (species composition, diversity and coverage) of understory community were monitored during study years (2007~2008). Canopy openness was different significantly among treatments but not for light availability. Based on the result of logistic regression, growth of height and leaf area of seedlings were significant variables on seedling survival. Height and leaf area of seedlings were increased during study years, although radial growth was reduced. During study years, there were no significant differences in species composition and diversity, and total coverage increased about 20%. Increase of resources by gap creation and understory removal likely affect growth of target species. Small gap creation was effective to reduce understory responses in composition and diverstiy. Synthesized, growth of target species and responses of understory community to small canopy gap creation exhibited, in short term, possibility of utilization in alternative forest restoration and management option. Long-term monitoring is necessary to certificate effect of artificial gap creation on forest restoration.

• KDI Journal of Economic Policy
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• v.12 no.2
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• pp.51-79
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• 1990

Research on technical efficiency, an important dimension of market performance, had received little attention until recently by most industrial organization empiricists, the reason being that traditional microeconomic theory simply assumed away any form of inefficiency in production. Recently, however, an increasing number of research efforts have been conducted to answer questions such as: To what extent do technical ineffciencies exist in the production activities of firms and plants? What are the factors accounting for the level of inefficiency found and those explaining the interindustry difference in technical inefficiency? Are there any significant international differences in the levels of technical efficiency and, if so, how can we reconcile these results with the observed pattern of international trade, etc? As the first in a series of studies on the technical efficiency of Korea's manufacturing industries, this paper attempts to answer some of these questions. Since the estimation of technical efficiency requires the use of plant-level data for each of the five-digit KSIC industries available from the Census of Manufactures, one may consture the findings of this paper as empirical evidence of technical efficiency in Korea's manufacturing industries at the most disaggregated level. We start by clarifying the relationship among the various concepts of efficiency-allocative effciency, factor-price efficiency, technical efficiency, Leibenstein's X-efficiency, and scale efficiency. It then becomes clear that unless certain ceteris paribus assumptions are satisfied, our estimates of technical inefficiency are in fact related to factor price inefficiency as well. The empirical model employed is, what is called, a stochastic frontier production function which divides the stochastic term into two different components-one with a symmetric distribution for pure white noise and the other for technical inefficiency with an asymmetric distribution. A translog production function is assumed for the functional relationship between inputs and output, and was estimated by the corrected ordinary least squares method. The second and third sample moments of the regression residuals are then used to yield estimates of four different types of measures for technical (in) efficiency. The entire range of manufacturing industries can be divided into two groups, depending on whether or not the distribution of estimated regression residuals allows a successful estimation of technical efficiency. The regression equation employing value added as the dependent variable gives a greater number of "successful" industries than the one using gross output. The correlation among estimates of the different measures of efficiency appears to be high, while the estimates of efficiency based on different regression equations seem almost uncorrelated. Thus, in the subsequent analysis of the determinants of interindustry variations in technical efficiency, the choice of the regression equation in the previous stage will affect the outcome significantly.

• Tuberculosis and Respiratory Diseases
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• v.60 no.6
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• pp.638-644
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• 2006

Backgrounds: This study investigated whether or not a polymorphism in the gene encoding the surfactant protein A(SP-A) has any bearing on the individual susceptibility to the development of chronic obstructive pulmonary disease(COPD) in a genetically homogenous Korean population. Methods: The genotypes of 19 COPD patients and 20 healthy neonates as controls were tested using a polymerase chain reaction followed by restriction fragment length polymorphism analysis for the SP-A gene. Results: The specific frequencies of the 6A2 and 6A18 alleles of SP-A1 and the 1A2 allele of SP-A2 were much higher in the COPD group than control group (p<0.05). However, the frequencies of the 6A3 and 6A4 alleles of SP-A1 and the 1A0 allele of SP-A2 in the COPD group were significantly lower than the control group. In the COPD group, the frequencies of the +50 locus genotypes GG of SP-A1 and the +9 locus genotypes CC of SP-A2 were 85.0% and 60.6%, respectively, and 19.7% and 24.8% in the control group, respectively. The frequencies of the polymorphic genotypes or alleles showed a statistically significant difference between the COPD group and the control group (P<0.05). Conclusion: A genetic polymorphism in SP-A is associated with the development of COPD in the Korean population.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.5
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• pp.64-79
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• 2010

Students with intellectual disabilities typically have great difficulties communicating their needs and wants and may get frustrated, anxious or show signs of aggressive behaviour. They are often unable to understand the concept of relationships with other people as well. This lack of social communication and interaction leads to poor motivation which increases other areas of difficulty in their lives. Therefore, to teach students with intellectual disabilities, it is essential to find special teaching methods to support their positive behavior. This paper proposes that special educational curriculum for students with intellectual impairments utilize natural environments(forests) and materials. The purpose of this study was to investigate the effects of Educational Programs Utilizing Forests on maladjusted behavior of students with mental retardation and to examine the positive effects of such planning practices. The subjects were middle school students who attended a special school for mentally-retarded students. They were divided into two separate groups- an experimental group and a control group. All subjects received the pre and post test using the same method. This program was applied to the formal educational process of middle school from March 1st to October 30th, 2009. In this experiment the results indicate that the effect of using a natural environment(forest) and the materials within a formal educational curriculum was positive as a type of horticultural therapy and that it supports positive behavior strategies in students with intellectual impairments. The usage of various natural materials including plants and flowers within the natural environments provide students with increased opportunities to participate. Teaching methods including natural materials help teachers engage with their students more easily during routine activities as their interest is already stimulated. This project will help students with intellectual impairments to build skills which enable effective participation and increase independence throughout their lives. This should be embedded into both routine and planned activities of the classroom Also, it offers a needed interior plan for the treatment space through an analysis of psychological factors of how the environment affects students.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.3
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• pp.28-37
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• 2016

Through the research and analysis on the hydrological environment and soil environment of habitats through documentary and field studies over 14 habitats of Euryale ferox Salisb. within Jeollabukdo, with the objective of acquiring the basic data for forming an environment based on plantation of reservoirs that are composed with Euryale ferox, the following results were obtained. As a result of analyzing the construction period of the habitats of Euryale ferox from a total of 14 places, the average period of duration after construction of all subject reservoirs appeared to be 71.8 years. Moreover, when examining the relationship between the age of reservoirs and eutrophication, it could be judged that at least the eutrophication of subsoil and water environment is not an obstacle to the growth of Euryale ferox grows in habitats that have a reservoir age of approximately 70 years or more. As a result of analyzing the gardening of soil sediment of the Euryale ferox habitats, the component ingredients appeared to be composed of 80.2% of clay, 16.7% of silt and 3.1% of sand, and the soil class pursuant to such was classified as 'heavy clay'. The organic matter contents of soil sediment appeared to be an average of 36g/kg, and there appeared to be no noticeable difference between the habitats and non-habitats of Euryale ferox. The water quality environment of Euryale ferox habitat appeared to be pH 6.5~7.9, concentration of dissolved oxygen to be $1.8{\sim}8.8mg/{\ell}$, concentration of COD to be $6.8{\sim}74mg/{\ell}$, floating materials to be $2.0{\sim}213mg/{\ell}$, total nitrogen to be $0.422{\sim}10.723mg/{\ell}$, and phosphate to be $0.003{\sim}0.126mg/{\ell}$. The average DO concentration of Aedang Reservoir at Jeongeup, Daejeong Reservoir at Imsil, and Myeongdeokji at Gimje with high vitality and green coverage ratio of Euryale ferox appeared to be $3.5mg/{\ell}$, total nitrogen to be $1.33mg/{\ell}$, and concentration of phosphorus-phosphate to be $0.061mg/{\ell}$. When comparing such with the entire average value, the DO and total nitrogen concentration appeared to be rather low, and the phosphorus-phosphate concentration appeared to be higher by two times or more, thus, an in-depth study on the correlation of the vitality of Euryale ferox Salisb. and concentration of phosphorate-phosphorus will be needed in the future.

• Journal of the Korean Society of Earth Science Education
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• v.10 no.1
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• pp.50-61
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• 2017

The purpose of this study is to analysis eye tracking for high school students' learning styles in the process of solving in the behavioral domains of the College Scholastic Ability Test on Earth Science I. The subjects of this study were 50 students from two classes out of 4 classes in E high school in Chungcheong province. Among them, we conducted experiments by randomly sampling 2 students of each type of learning based on the criteria that they had not encountered the problem of Earth Science I from the past two years. The findings indicate that the item correctness rate of divergers, assimilators, convergers, and accommodators were higher in the knowledge domain, application domain, knowledge-understanding domain, and understanding domain. This confirms that there is a difference among the four learning styles in the level of achievement according to the behavioral areas of the assessment questions. The latter finding was that the high eye-share of AOI 2 appeared higher than AOI 1, 3, 4 in the course of solving the problems. This is because the four types of learners pay more careful attention to the AOI 2 area, which is the cue-or-information area of problem solving, that is, the Table, Figure, and Graph area. Therefore, in order to secure the fairness and objectivity of the selection, it is necessary that an equal number of questions of each behavioral domain be selected on the Earth Science I Test of the College Scholastic Ability Test in general. Besides, it seems to be necessary that the knowledge, understanding, application, and the behavior area of the inquiry be highly correlated with the AOI 2 area in development of test questions.