• The Journal of Korean Medicine
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• v.26 no.2 s.62
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• pp.152-165
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• 2005

Background: The use of herbal preparations as remedies for various medical conditions has continuously increased in Korea Large proportions of Korean patients use herbal medicinal products, folk remedies, and food supplements. However, studies on the safety of herbal products arc conducted on a less than sufficient basis even in the countries like Korea where herbal medicine is being used extensively. Some of the reports on the safety of herbs were done by the doctors of western medicine but lack of knowledge and misclassification led to misunderstandings. Objecitves: This study aims to review the recent evidences on hepatotoxic events associated with the use of herbal medicinal products, folk remedy, and food supplements. In the process, this review will grasp trends in this field of studies and will direct further researches into the right direction. Methods: Systematic literature searches were performed on MedRic and MEDLIS in Korea. Screening and selection of the articles and the extraction of data were performed independently by two of authors. There were no restrictions regarding the published date. In order to avoid bias, the articles written by medical doctors, not by oriental doctors were selected. 43 journals were chosen for the review. Results: Analyzing the number of journals, studies on the drug-induced liver injury were increased after the year 2000. The proportion of herbal and folk remedy associated hepatotoxic injuries in all drug-induced liver injury was $21.0\%-30.0\%$. But criterion for herbal medicine is rather vague and limited objective data hindered objectiveness. Few of single medicinal herbs and combination preparations were associated with hepatotoxic injuries. But because of lack of objectivity, further researches must be conducted to yield more concrete results. Conclusions: yield more concrete results. Incidence figures are largely unknown, and in most cases a causal attribution is not established. The challenge for the future is to systematically research this area, educate all parties involved, and minimize patient risks.

• Journal of Labour Economics
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• v.25 no.1
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• pp.131-160
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• 2002

This article tried to find out the individual wage effect of training. This Article used 1998, 1999 KLIPS(Korea Labor and Income Panel Study) panel data. The size of the individual wage effect of training was twice of tenure's, and had significance. Training had a good effect on the job satisfaction and carrier development. To overcome self selection bias, this article regressed the first difference of wage equations, but we didn't get the significant results. Dividing sample into quitters and non-quitters in order to investigate the relation between training cost and benefit, we regressed separately the each first difference of wage equation. On quitters, the individual effect of training appeared significantly, but on non-quitters, it didn't. This results mean that employer does not raise wage rate according to upgraded skill originated in incumbent's training. And the results also mean that the upgraded skill of employee who quit pre-employer is recognized by new employer, and his wage rate rises in his new job.

• The Journal of the Korea Contents Association
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• v.18 no.4
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• pp.688-697
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• 2018

The following research was conducted to encourage residents in urban areas to move to rural areas, and to improve the residential environments in those rural areas. Current policies for rural village development Project were analyzed, and policy implications were proposed. Residents in rural villages participated in a 12-question survey that asked their priorities prior to moving to the area, and factors contributing to resident satisfaction. Importance and Performance Analysis (IPA) was performed to present potential development strategies in the construction business. As a result, 'natural environment and landscapes' had the highest priority and satisfaction, whereas 'lack of public transportation and accessibility' and 'road conditions and parking facilities' had high priorities but low satisfaction levels. Thus, it is important to take nature and environment, as well as accessibility into consideration when moving to rural villages. Although this research was based on residents' bias, and the sample area was limited, these conclusions still offer important policy agreement provide of future rural villages location selection and establishment of land use planning.

• Journal of Distribution Research
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• v.12 no.4
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• pp.27-47
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• 2007

Using survey data and the Heckit model that adequately controls the sample selection bias, we analyze shoppers expenditure through two major emerging shopping channels: Internet shopping and TV home shopping channels. Age, Internet experience, daily Internet usage, the number of computers are factors that affect the ratio of consumers' expenditure through Internet shopping relative to the expenditure through TV home shopping. Shopping frequency which represents the shoppers' incentives to reduce transaction costs also has a positive effect on the proportion of shoppers' expenditure through the Internet shopping. Shoppers' perceptions of convenience, reliability, speed, and diversity are also shown to affect shoppers' relative expenditure ratio through Internet shopping. In contrast, shoppers' perception of prices does not seem to affect their purchasing behavior.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.23
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• pp.10325-10328
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• 2015

RASSF1A, regarded as a candidate tumor suppressor, is frequently silenced and inactivated by methylation of its promoter region in many human tumors. However, the association between RASSF1A promoter methylation and lung cancer risk remains unclear. To provide a more reliable estimate we conducted a meta-analysis of cohort studies to evaluate the potential role of RASSF1A promoter methylation in lung carcinogenesis. Relevant studies were identified by searches of PubMed, Web of Science, ProQest and Medline databases using the following key words: 'lung cancer or lung neoplasm or lung carcinoma', 'RASSF1A methylation' or 'RASSF1A hypermethylation'. According to the selection standard, 15 articles were identified and analysised by STATA 12.0 software. Combined odds ratio (OR) and 95% confidence interval (CI) were used to assess the strength of the association between RASSF1A promoter methylation and lung cancer risk. A chi-square-based Q test and sensitivity analyses were performed to test between-study heterogeneity and the contributions of single studies to the final results, respectively. Funnel plots were carried out to evaluate publication bias. Overall, a significant relationship between RASSF1A promoter methylation and lung cancer risk (OR, 16.12; 95%CI, 11.40-22.81; p<0.001) with no between-study heterogeneity. In subgroup analyses, increased risk of RASSF1A methylation in cases than controls was found for the NSCLC group (OR, 13.66, 95%CI, 9.529-19.57) and in the SCLC group (OR, 314.85, 95%CI, 48.93-2026.2).

• Journal of Korean Society for Quality Management
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• v.44 no.2
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• pp.341-356
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• 2016

Purpose: The purpose of this paper is to study whether the adoption of Six Sigma quality management by a firm positively affects its financial performance. The correlation between the duration of Six Sigma implementation period and the financial status of the firm is investigated as well. Methods: We conduct the analysis using data from Manufacturing Industry Productivity Panel Survey 2013 provided by Korea Productivity Center and Ministry of Trade, Industry and Energy. Propensity score matching is used to reduce sample selection bias of observational study. Furthermore, we use multiple linear regression in order to study the relationship between the implementation of Six Sigma quality management and financial performance. The return on assets and ratio of net income to net sales are considered as dependent variable and implementation of Six Sigma as independent variable. Results: The indication of this analysis is that implementation of Six Sigma quality management does not significantly enhance financial status. The firms that adopted Six Sigma quality management were categorized into three groups according to the implementation period. Comparison of each group with the firms that do not adopt Six Sigma quality management does not show statistically significant enhancement of financial status. Conclusion: In conclusion, both adoption and duration of six sigma quality management do not affect financial performance significantly.

• Journal of Preventive Medicine and Public Health
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• v.31 no.2 s.61
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• pp.265-274
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• 1998

To investigate the change of nitric oxide(NO), copper, and zinc in serum on smoking and alcohol ingestion in young adults, this study was performed in a cross-sectional study in 127 healthy men in Korea who had HBsAg(-), HCVAb(-), and no symptomatic liver, heart, gastrointestinal, chronic diseases, and inflammatory sign(lower than 10,000 white blood cell count in CBC). At the men's entry into the study, blood samples were drawn from each subject and immediately centrifuged for analysis of NO, copper, and zinc. Each man completed a questionnaire that provided information on smoking, alcohol intake and present and past medical history NO was analyzed by HPLC(Green et al., 1982), copper and zinc by atomic absorption spectrophotometer with air-acetylene flame and total cholesterol(TC) by Spectrum EPX. Smoking(number of cigarettes per day and pack-year) and alcohol intake was grouped fertile. Copper was adjusted for age and zinc and for age and TC. NO, copper, and zinc on smoking and alcohol ingestion were analyzed in general linear models, respectively. NO, copper and zinc in serum did not show statistical differences between non-smoking and high-smoking group and no-alcohol intake and high-alcohol intake group. This study suggested that copper, zinc, and NO was not. good biological marker for early effect by smoking and alcohol intake in young adults. However, selection bias should be considered in evaluation of this result. A large prospective study will be needed in advance on usefulness of copper, zinc, and NO as a marker for risk factors and early change of atherosclerosis.

• Convergence Security Journal
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• v.7 no.3
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• pp.51-60
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• 2007

Infinite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, exponential distribution and Rayleigh distribution model was reviewed, proposes the mixture reliability model, which made out efficiency substituted for situation for failure time Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on SSE and Kolmogorov distance, for the sake of efficient model, was employed. Analysis of failure using S27 data set for the sake of proposing shape parameter of the mixture distribution was employed. This analysis of failure data compared with the mixture distribution model and the existing model(using arithmetic and Laplace trend tests, bias tests) is presented.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5573-5578
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• 2015

Background: A systematic review and meta-analysis were performed to compare the post-recurrence survival with hepatic re-resection versus transarterial chemoembolization (TACE) for recurrent hepatocellular carcinoma (HCC) after initial resection. Materials and Methods: All relevant papers were searched via PubMed, EMBASE, and Cochrane Library databases. Hazard ratios (HRs) with 95% confidence intervals (CIs) were pooled using a random-effects model. Subgroup analysis was performed according to country. Sensitivity analysis was performed in studies which clearly reported the recurrent regions, in moderate/high-quality studies, in studies published in full-text form, and in studies published after 2005. Results: In total, twelve papers were included in our study. Five and seven of them were of moderate- and poor-quality, respectively. The overall meta-analysis demonstrated a statistically significantly higher post-recurrence survival in the hepatic re-resection group than in those undergoing TACE (HR=0.64, 95%CI=0.52-0.79, P<0.0001). Heterogeneity was statistically significant and statistical significance remained in the subgroup analysis. Sensitivity analyses were also consistent with the overall analysis. Conclusions: Hepatic re-resection might provide a better post-recurrence survival than TACE for recurrent HCC after initial resection. However, considering the low quality of published studies and the potential bias of treatment selection, further randomized trials should be warranted to confirm these findings.

• The Journal of Korean Medicine
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• v.25 no.3
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• pp.78-89
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• 2004

Background : A report published by the National Institute of Toxicological Research (NITR) in January 2004 about toxic hepatitis in Korea contained the result of analysis on 55 cases of severe toxic hepatitis from 7 university hospitals for 8 months. NITR claimed that the extrapolated annual frequency of severe toxic hepatitis in Korea was 1904 cases per year. They also claimed that the most frequent etiology of severe toxic hepatitis were herbal medications and similar plant preparations (61.7%), contrasted with traditional therapeutic preparations and healthy foods (29.1%). I have investigated that report to be certain of the result because it is a very important subject for public health and society in Korea. Results : The NITR report has too many problems to have faith in its results. They include the following: 1. The report uses only 55 cases to estimate annual prevalence rate of severe toxic hepatitis in Korea. 2. There was a large regional preponderancy in the NITR report (2 cases in Seoul from a population of 10.17 million, 19 cases in Gwangju from a population of 1.4 million) 3. There was another preponderancy that selected much fewer cases caused by western medication (9.1%) than other reasons. 4. The NITR report used a modified scale than that officially recognized to diagnose toxic hepatitis. 5. There was a mistake using the scale to adapt the right indications. 6. They collected cases before beginning the study, although it was a prospective study. There was also not any questionnaire or other materials concerned with alcohol, drugs, or history of past liver disease. Conclusions : NITR is one of the important official arms of the government of Korea. Nevertheless, there is a severe problem in validity because of selection bias, uncertain accuracy, and insufficiency of raw materials in the report. Therefore it seems incorrect to generalize the results of the report and there is a lack of confidence in it as a national study publishing by the NITR.