• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6769-6773
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• 2013

Background: Few local studies have explored the process of adverse transition of smoking stages among adolescents. The present investigation aimed to identify adverse transitions prospectively from the early stages till the escalation of the stages after one year. Materials and Methods: Data were collected in two waves from a cohort of 2,552 adolescents aged 12-13 years old studying in 15 secondary schools based in Kinta, Perak. A multistage sampling method was used to select the schools and a self-administered structured questionnaire was applied to help categorize the participants into five different smoking stages. Nonsmokers were divided into never smokers and susceptible never smokers. Ever-smokers were categorized as experimenters, current smokers or ex-smokers. Results: Among the participants 46.8% were Malay, 33.5% Chinese and 17.1% Indians. At baseline, we had 85.3% non-smokers and 14.6% ever smokers. Incidence of adverse transition among all our participants was 24.1%, with a higher value among male participants (16.8%). A higher proportion of susceptible never smokers and experimenters progressed to current smoking stage compared to never smokers. Conclusions: This study highlights the changes and patterns of adverse transition among adolescents. Male adolescents, those who are susceptible to smoking and those who had already tried experimenting with cigarettes have a higher chance of escalating to a higher smoking stage.

• Journal of the Korean Solar Energy Society
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• v.30 no.5
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• pp.107-114
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• 2010

Understanding of reflectance of solar concentrators is important for assessing concentration performance. However inaccurate data about refractive indices of constituent materials and dust accumulation on the surface often prevent figuring out reflectance variations. The current study proposes an approach calculating concentrator reflectance based on the refractive index of glass obtained from reflectance and transmittance measurements. This approach improved accuracy of solar-averaged reflectance from 2.9% to 0.4% compared to the use of existing reference data. Reflectance variations with incidence angles are negligible up to $60^{\circ}C$ at various glass thicknesses. When concentrators are contaminated with dust during 2 months specular reflectance loss of vertically exposed concentrators is less than 7%. However for horizontally exposed concentrators the loss significantly increases up to 40% while dependence of reflectance on incidence angles becomes strong. Measurements of hemispherical reflectance indicate that 80 percentage of the loss comes from scattering rather than absorption by dust. Data of refractive index and reflectance provided in the current study will help estimate or model the concentrated solar flux.

• Journal of Korean Medical Science
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• v.33 no.52
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• pp.331.1-331.17
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• 2018

Human Papillomavirus (HPV) infection is the most common sexually transmitted infection and is associated with the development of cervical cancer. The purpose of this report is to provide the literature evidences on selecting the HPV vaccine for national immunization program (NIP) in Korea. To complete these tasks, we reviewed domestic and foreign literature on the current status of HPV infection, efficacy and effectiveness of HPV vaccine, safety of vaccine and cost effectiveness analysis of vaccination business. Given that the median age of first sexual intercourse is continuing to fall, this may have serious implications for HPV infection and cervical cancer incidence at the age of 20s. The World Health Organization recommends that the HPV vaccination should be included in the NIP being implemented in each country. Both the bivalent and quadrivalent vaccines have a 90% or greater preventive efficacy on cervical intraepithelial lesion 2-3 and cervical cancer by the HPV 16 or HPV 18. In the future, if HPV vaccination rate as part of NIP increases, it is expected that the incidence of HPV infection, genital warts, and cervical precancerous lesions will be decreased in the vaccination age group. Therefore, in order to increase the HPV vaccination rate at this point in Korea, social consensus and efforts such as the introduction and promotion of HPV vaccine to the NIP according to appropriate cost-effectiveness analysis are required.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.27 no.4
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• pp.101-109
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• 2014

Objective : The purpose of this study is to summarize the differential diagnosis between allergic and nonallergic rhinitis and suggest management. Methods : We reviewed the current update of medical history and physical examination for allergic and nonallergic rhinitis. Then we analyzed clinical characteristics according to onset age, gender incidence and state of nasal symptoms, etc. Results : 1. Patients with nonallergic rhinitis tend to develop symptoms at a later age(>35 years of age), and there is a female-to-male incidence ratio for nonallergic rhinitis of 2:1 to 3:1. 2. Patients with nonallergic rhinitis report nasal congestion, nasal rhinorrhea and more often report postnasal drip rather than sneezing and itching, which are predominant symptoms of allergic rhinitis. And the nasal mucosa in nonallergic rhinitis usually looks normal. 3. Patients with nonallergic rhinitis have few complaints of concomitant symptoms of allergic symptoms and the absence of other atopic diseases in the patient or in the family supports the diagnosis of nonallergic rhinitis. 4. Common triggers of nonallergic rhinitis are nonspecific irritant exposures and many patients with nonallergic rhinitis find that antihistamines have no benefit. Conclusions : The differential diagnosis between allergic and nonallergic rhinitis is clinical and relies on a detailed medical history and physical examination.

• Journal of Medicine and Life Science
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• v.15 no.2
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• pp.46-50
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• 2018

Cancer, a leading mortality disease following cardiovascular disease worldwide, has high incidence as one out of every four adults in Korea. It was known to be caused by several reasons including somatic mutation, activation of oncogene and chromosome aneuploidy. Cancer cells show a faster growth rate and have metastatic and heterogeneous cell populations compared to normal cells. Cancer stem cells, the most invested field in cancer biology, is a theory to explain heterogeneous cell populations of cancer cells among several characteristics of cancer cells, which is providing the theoretical background for incidence of cancer and treatment failure by drug resistance. Cancer stem cells initially explain heterogeneous cell populations of cancer cells based on the same markers of normal stem cells in cancer, in which only cancer stem cells showed heterogeneity of cancer cells and tumor initiating ability of leukemia. Based on these results, cancer stem cells were reported in various solid cancers such as breast cancer, liver cancer, and lung cancer. Breast cancer stem cells were first reported in solid cancer which had tumor initiating ability and further identified as anti-cancer drug resistance. There were several identification methods in breast cancer stem cells such as specific surface markers and culture methods. The discovery of cancer stem cells not only explains heterogeneity of cancer cells, but it also provides theoretical background for targeting cancer stem cells to complete elimination of cancer cells. Many institutes have been developing new anticancer drugs targeting cancer stem cells, but there have not been noticeable results yet. Many researchers also reported a necessity for improvement of current concepts and methods of research on cancer stem cells. Herein, we discuss the limitations and the perspectives of breast cancer stem cells based on the current concept and history.

• The Plant Pathology Journal
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• v.39 no.6
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• pp.548-565
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• 2023

Armillaria root disease affects forests around the world. It occurs in many habitats and causes losses in the infested stands. Weather conditions are important factors for growth and development of Armillaria species. Yet, the relation between occurrence of damage caused by Armillaria disease and weather variables are still poorly understood. Thus, we used generalized linear mixed models to determine the relationship between weather conditions of current and previous year (temperature, precipitation and their deviation from long-term averages, air humidity and soil temperature) and the incidence of Armillaria-induced damage in young (up to 20 years old) and older (over 20 years old) coniferous stands in selected forest districts across Poland. We used unique data, gathered over the course of 23 years (1987-2009) on tree damage incidence from Armillaria root disease and meteorological parameters from the 24-year period (1986-2009) to reflect the dynamics of damage occurrence and weather conditions. Weather parameters were better predictors of damage caused by Armillaria disease in younger stands than in older ones. The strongest predictor was soil temperature, especially that of the previous year growing season and the current year spring. We found that temperature and precipitation of different seasons in previous year had more pronounced effect on the young stand area affected by Armillaria. Each stand's age class was characterized by a different set of meteorological parameters that explained the area of disease occurrence. Moreover, forest district was included in all models and thus, was an important variable in explaining the stand area affected by Armillaria.

• Current Research on Agriculture and Life Sciences
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• v.16
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• pp.84-95
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• 1998

Apple Marssonina blotch, caused by Diplocarpon mali, which has been increasing on apple trees and become one of the most serious diseases on apple trees in Korea since the begining of 1990's. In this study, ecology of Marssonina blotch including disease incidence and spore dispersals was surveyed from 1992 to 1995 in Kyungpook, and factors influencing the incidence of the disease were analyzed. Marssonina blotch began to occur on apple leaves in June and was observed commonly in most of apple orchards after August, and increased rapidly in September. The incidence of this disease was high at the year of low temperature and a lot of precipitation. The conidia discharge began to occur in May and continued to October, and the peak period of spore release was in August and usually more than 70% of total spore release of the year released from August to September. The incidence of the disease was high in the northern and mountain are as such as Yeongjoo, Chungsong, Andong, and relatively low in the southern areas such as Kunwi, Yongchon. Jonathan cultivar was the most susceptible to Marssonina blotch, and Jonagold, Sekaiichi was secondly susceptible and the next Fuji was more susceptible than Tsugaru. The incidence of the disease was relatively high in orchards which cultivation management of irrigation, drainage, air circulation, fertilization, and fungicide spraying were poor.

• Journal of Preventive Medicine and Public Health
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• v.41 no.1
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• pp.23-29
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• 2008

Objectives : We examined the association between alcohol consumption and incidence of colorectal cancer in elderly Koreans. Methods : The cohort members (n=14,304) consisted of 4,834 males and 9,470 females derived from the Korea Elderly Pharmacoepidemiologic Cohort (KEPEC), a population-based dynamic cohort. They were aged 65 years old or older and lived in Busan between 1993-1998; they were beneficiaries of the Korean Medical Insurance Corporation (KMIC). Baseline information was surveyed by a self-administered, mailed questionnaire. This study population was restricted to 14,304 participants who reported alcohol drinking habits on the questionnaire and had not been diagnosed with colorectal cancer at baseline. The adjusted hazard ratios (aHR) of status, type, frequency and daily average amount of alcohol consumption were computed with Cox's proportional hazard model, with the never-drinkers as a reference group and controlling for age and gender. Results : After 4.82 person-years of mean follow-up 112 cases of colorectal cancer occurred. The incidence densities of colorectal cancer were 161 (95% CI=123-200) for never-drinkers, 219 (95% CI=125-339) for ex-drinkers, and 137 (95% CI=84-189) for current-drinkers per 100,000 person-year. The status, type, frequency, and daily average amount of alcohol consumption were not significantly related to the incidence of colorectal cancer after controlling for age and gender. Conclusions : There was no significant association between alcohol consumption and colorectal cancer among elderly people after controlling for age and gender.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3155-3160
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• 2016

Background: L-asparaginase (ASNase) is commonly used in the treatment of acute lymphoblastic leukemia (ALL) and natural killer (NK)/T-cell lymphoma. This study was designed to describe the incidence of toxicity associated with ASNase in Asian adults. Secondary objectives were to investigate the management and impact of toxicity on subsequent ASNase use, and to compare the actual management against current recommendations. Materials and Methods: In this retrospective, multi-center, observational study, Asian patients ${\geq}18$ years old who received ${\geq}1$ dose of the native E. coli ASNase from 2008 to 2013 were included. Patients were excluded if they did not receive ASNase. Endpoints of this study were development of specific toxicities, whether ASNase was discontinued or re-challenged, and developmentg of recurrent toxicity. All data analyses were performed using SPSS version 20.0. Results: A total of 56 patients were analyzed. Mean (${\pm}SD$) age was 36.2 (${\pm}15.2$) years old, with 62.5% being males, 55.4% with ALL and 28.6% with NK/T-cell lymphoma. Hypersensitivity (12.5%) was associated with the highest incidence of toxicity (6 out of 7 patients had Grade 3 and 4 toxicity), followed by 10.7% for hepatic transaminitis, 3.6% for non-CNS thrombosis and 1.8% each for hyperbilirubinemia and pancreatitis. Hypersensitivity recurred in the 3 patients who were re-challenged with E. coli ASNase. Conclusions: ASNase is associated with a wide range of toxicities, with hypersensitivity being the most commonly observed among Asian adult patients.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.24
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• pp.10565-10571
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• 2015

Gastric cancer incidence rates vary dramatically by world region with East Asia having the highest rate. The Asian population of the United States (US) is growing rapidly and over 17 million Americans are of Asian descent. A majority of Chinese, Korean and Vietnamese Americans are immigrants. Americans of East and Southeast Asian descent experience marked gastric cancer disparities and the incidence rate among Korean men in the US is over five times higher than the incidence rate among non-Hispanic white men. Randomized controlled trials have provided evidence for the effectiveness of helicobacter pylori identification and eradication in preventing gastric cancer. Additionally, Japan and South Korea have both experienced improvements in gastric cancer mortality following the implementation of programs to detect early stage gastric cancers. There are currently no clear US guidelines regarding the primary and secondary prevention of gastric cancer in high-risk immigrant populations. However, it is likely that a proportion of US physicians are already recommending gastric cancer screening for Asian patients and some Asian immigrants to the US may be completing screening for gastric cancer in their native countries. Surveys of US primary care physicians and Asian American communities should be conducted to assess current provider practices and patient uptake with respect to gastric cancer prevention and control. In the absence of clinical guidelines, US health care providers who serve high-risk Asian groups could consider a shared decision-making approach to helicobacter pylori identification and eradication, as well as gastric endoscopy.