• Title/Summary/Keyword: restriction factors

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Solid Waste Disposal Site Selection in Rural Area: Youngyang-Gun, Kyungpook (농촌지역 쓰레기 매립장 입지선정에 관한 연구 -경상북도 영양군을 사례로-)

  • Park, Soon-Ho
    • Journal of the Korean association of regional geographers
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    • v.3 no.1
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    • pp.63-80
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    • 1997
  • This study attempts to establish the criteria of site selection for establishing solid waste disposal facility, to determine optimal solid waste disposal sites with the criteria, and to examine the suitability of the selected sites. The Multi-Criteria Evaluation(MCE) module in Idrisi is used to determine optimal sites for solid waste disposal. The MCE combines the information from several criteria in interval and/or ratio scale to form a single index of evaluation without leveling down the data scale into ordinal scale. The summary of this study is as follows: First, the considerable criteria are selected through reviewing the literature and the availability of data: namely, percent of slope, fault lines, bedrock characteristics, major residential areas, reservoirs of water supply, rivers, inundated area, roads, and tourist resorts. Second, the criteria maps of nine factors have been developed. Each factor map is standardized and multiplies by its weight, and then the results are summed. After all of the factors have been incorporated, the resulting suitability map is multiplied by each of the constraint in turn to "zero out" unsuitable area. The unsuitable areas are discovered in urban district and its adjacencies, and mountain region as well as river, roads, resort area and their adjacency districts. Third, the potential sites for establishing waste disposal facilities are twenty five districts in Youngyang-gun. Five districts are located in Subi-myun Sinam-ri, nine districts in Chunggi-myun Haehwa-ri and Moojin-ri, and eleven districts in Sukbo-myun Posan-ri. The first highest score of suitability for waste disposal sites is shown at number eleven district in Chunggi-myun Moojin-ri and the second highest one is discovered at number twenty one district in Sukbo-myun Posan-ri that is followed by number nine district in Chunggi-myun Haehwa-ri, number seventeen and twenty three in Sukbo-myun Posan-ri, and number two in Subi-myun Sinam-ri. The first lowest score is found in number six district in Chunggi-myun Haehwa-ri, and the second lowest one is number five district in Subi-myun Sinam-ri. Finally, the Geographic Information System (GIS) helps to select optimal sites with more objectively and to minimize conflict in the determination of waste disposal sites. It is important to present several potential sites with objective criteria for establishing waste disposal facilities and to discover characteristics of each potential site as a result of that final sites of waste disposal are determined through considering thought of residents. This study has a limitation of criteria as a result of the restriction of availability of data such as underground water, soil texture and mineralogy, and thought of residents. To improve selection of optimal sites for a waste disposal facility, more wide rage of spatial and non-spatial data base should be constructed.

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Spatio-Temporal Variation Characteristics of Primary Productivity and Environmental Factors of Shellfish Mariculture in Jaran Bay, Korea (자란만 패류양식어장의 기초생산력 및 환경인자 변동 특성)

  • Lee, Dae In;Choi, Yong-Hyeon;Hong, SokJin;Kim, Hyung Chul;Lee, Won-Chan
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.5
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    • pp.721-734
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    • 2022
  • This study analyzed the spatio-temporal variation characteristics of major environmental factors such as primary productivity (PP), chlorophyll a, nutrients, sinking particle matters, and organic contamination and biochemical composition of surface sediment on a monthly basis for approximately 2 years around shellfish mariculture in Jaran Bay, Korea. In addition, PP in Jaran Bay was compared with that in other coastal areas and related policy plans were proposed. The average PP of the study area was high in summer and autumn with 6.43~115.43 mgC m-2 hr-1 range. This was lower than that in Gamak Bay and Masan Bay, whereas higher than that in Garorim Bay and the West Sea. The PP in coastal waters, where many aquaculture farms were distributed, significantly fluctuated. The different size compositions of phytoplanktons constituting chlorophyll a slightly varied by month, and little restriction existed on the productivity of phytoplanktons owing to the depletion of nutrients. Typically, the Redfield ratio was less than 16, indicating that nitrogen was the limiting factor for the growth of phytoplanktons. The biochemical composition of particulate organic matters in the water column showed the highest carbohydrates, but lipids and protein contents were high in surface sediments. The concentration of TOC and AVS of the surface sediments was high at inside of bay, and sometimes, exceeded the environmental criteria of fishing grounds. The organic C:N ratio of sediments ranged from 8.1 to 10.4 on average. PP had the highest correlation with chlorophyll a, nitrogen and protein of particle organic materials. Recently, chlorophyll a, DIN, and DIP of water column trends tended to decrease, however, the contamination of sediments increased. Considering the annual PP of 125.9 gC m-2 yr-1 and mariculture area (oyster) of 4.97 km2, the annual carbon production from phytoplanktons was estimated to be about 625 tons, and the annual total wet weight of shellfish (oyster) was estimated to be about 6,250 tons.

Analysis of the association between bronchial hyperresponsiveness and genetic polymorphism of β2-adrenoceptor in adolescents with long-term asthma remission (장기간 천식 관해 청소년에서 지속되는 기관지 과민성과 β2-아드레날린 수용체 유전자 다형과의 연관성 분석)

  • Kang, Hee;Koh, Young Yull
    • Clinical and Experimental Pediatrics
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    • v.50 no.6
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    • pp.556-564
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    • 2007
  • Purpose : We hypothesized that the persisting bronchial hyperresponsiveness (BHR) of adolescents with asthma remission may be controlled mainly by genetic factors, and the BHR of symptomatic asthma by airway inflammation. ${\beta}_2$-adrenoceptor gene is considered to be a candidate gene in the development of BHR. Thus, ${\beta}_2$-adrenoceptor gene polymorphism may be associated with the BHR of adolescents with asthma remission, but not with the BHR of symptomatic asthma. To evaluate this hypothesis, ${\beta}_2$-adrenoceptor gene polymorphism at 2 sites (Arg16-Gly, Gln27-Glu) were examined. Methods : Two hundred two adolescents with BHR ($PC_{20}<18\;mg/mL$) and long term remission (neither asthma-related symptoms nor medication during the previous 2 years) of their asthma (remission group), 182 adolescents with symptomatic asthma (symptomatic group), and 200 healthy adolescents (control group) were studied. Asthma phenotypes were determined using methacholine bronchial provocation test and skin prick test. Genotypes of ${\beta}_2$-adrenoceptor polymorphism were evaluated by PCR-based methods. Results : Gly/Gly allele and Gly16-Gln27 haplotype were more prevalent in the remission group than in the control group (P=0.01, P=0.02), although there was no difference between the symptomatic group and the control group. In the remission group, there was significant difference in geometric mean of $PC_{20}$ among the 3 groups subdivided by the number of Gly16-Gln27 haplotype, showing that the Gly16-Gln27 haplotype was positively associated with BHR. However, no association was found between Gly16-Gln27 haplotype and BHR in the symptomatic group. Conclusion : This study demonstrates that ${\beta}_2$-adrenoceptor polymorphism at amino acid 16 and 27 was associated with BHR persisting in adolescents with asthma remission.

Fate Analysis and Impact Assessment for Vehicle Polycyclic Aromatic Hydrocarbons (PAHs) Emitted from Metropolitan City Using Multimedia Fugacity Model (다매체거동모델을 이용한 대도시 자동차 배출 Polycyclic Aromatic Hydrocarbons (PAHs) 거동 해석 및 영향평가)

  • Rhee, Gahee;Hwangbo, Soonho;Yoo, ChangKyoo
    • Korean Chemical Engineering Research
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    • v.56 no.4
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    • pp.479-495
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    • 2018
  • This study was carried out to research the multimedia fate modeling, concentration distribution and impact assessment of polycyclic aromatic hydrocarbons (PAHs) emitted from automobiles, which are known as carcinogenic and mutation chemicals. The amount of emissions of PAHs was determined based on the census data of automobiles at a target S-city and emission factors of PAHs, where multimedia fugacity modeling was conducted by the restriction of PAHs transfer between air-soil at the impervious area. PAHs' Concentrations and their distributions at several environmental media were predicted by multimedia fugacity model (level III). The residual amounts and the distributions of PAHs through mass transfer of PAHs between environment media were used to assess the health risk of PAHs at unsteady state (level IV), where the sensitivity analyses of the model parameter of each variable were conducted based on Monte Carlo simulation. The experimental result at S-city showed that Fluoranthene among PAHs substances are the highest residual concentrations (60%, 53%, 32% and 34%) at all mediums (atmospheric, water, soil, sediment), respectively, where most of the PAHs were highly accumulated in the sediment media (more than 80%). A result of PAHs concentration changes in S-city over the past 34 years identified that PAHs emissions from all environmental media increased from 1983 to 2005 and decreased until 2016, where the emission of heavy-duty vehicle including truck revealed the largest contribution to the automotive emissions of PAHs at all environment media. The PAHs concentrations in soil and water for the last 34 years showed the less value than the legal standards of PAHs, but the PAHs in air exceeded the air quality standards from 1996 to 2016. The result of this study is expected to contribute the effective management and monitoring of toxic chemicals of PAHs at various environment media of Metropolitan city.

Practical Applications of DNA Marker-Assisted Selection and OPU-Derived IVF Embryo Transfer for the Production of High Quality Meat in Hanwoo II. Production of IVF Embryos Derived Transvaginal Ovum Pick-up from DNA Marker-Proved Hanwoo (유전자 분석을 통하여 선발된 한우로부터 초음파 유래 체외수정란 이식에 의한 고품질 한우 생산기술의 실용화 II. DNA 검정우로부터 초음파 유래 체외수정란의 생산에 관한 연구)

  • 박희성;이지삼;진동인;박준규;홍승표;이명열;정장용
    • Journal of Embryo Transfer
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    • v.16 no.3
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    • pp.193-201
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    • 2001
  • This study was designed to examine the factors affecting in fertilization and development of embryos in vitro, and to examine whether zone drilling by laser irradiation can improve the hatching rate of IVF embryos from DNA marker-proved Hanwoo. DNA markers related to marbling score were identified using DNA fingerprinting with Ml3 probe and restriction enzyme Hae III. Oocytes were aspirated from immature ovarian follicles using a combined method of rectal ovarian-palpation and transvaginal ultrasound-guidance(6.5MHz) under local anesthesia. The aspirated oocytes were washed twice with fresh D-PBS containing 5% FBS and were rewashed 4 to 5 times with TCM-199 containing 5% FBS. A morphological grade of I to IV was assigned to each oocyte. Data were analyzed using the GLM procedure of SAS. Sperm separation methods did not have any significant effect on cleavage or developmental abilities of IVF embryos. Significantly(P<0.05) higher cleavage rate was observed in embryos from GI(60.0%, 3/5), GII(69.2%, 18/26) and GIII(62.1%, 59/95) compared to embryos from GIV oocytes(36.2%, 25/69). And the developmental rate to blastocyst stage was higher(P<0.05) in embryos from GI(33.3%, 1/3) and GII oocytes(38.9%, 7/18) than those from GIII(16.9%,10/59) and GIV oocytes(4.0%, 1/25). There was no significant difference in development of IVF embryos to blastocyst by media for in vitro culture. Proportion of hatched blastocyst was significantly(P<0.05) higher in embryos received zona drilling by laser than those of non-drilled.

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A study on ceremonial costume and Confucianism is Chosun Dynasty - Focusing on Men's Po - (조선시대(朝鮮時代) 유교사상(儒敎思想)과 의예복연구(儀禮服硏究) - 남자(男子) 포(袍)를 중심(中心)으로 -)

  • Lee, Sun-Jae
    • Journal of the Korean Society of Costume
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    • v.16
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    • pp.221-229
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    • 1991
  • This thesis aims at reviewing the wearing aspect and formation of Chosun ceremonial dresses for meal and finding out the thought reflected by them from the standpoint that dresses themselves should be taken as one of the phenomena in culture. That is men's ceremonial costumes and confucian costumes of the royal family and the gentry family in Chosun is reviewed focused on the formation and the wearing aspect of Po, Which is a kind of them. And in the context of the phase of the times. I also considered the thoughts reflected on the clothes such as confucianism, Ying & Yang Theory, and the symbol and the thoughts of patterns in relation to the clothes. Confucian influence was the main force for the Chosun prohibitions for clothes. The major reasons for the prohibitions for clothes were as follows. First, they reflected confucian Chung myoung chooui(the principle that everything should be where it belongs). That is the prohibitions for clothes were used in the means to maintain feudalistic social order. influenced by social rank system. Second, they reflected confucian ethics in the means to recover social disciplines with the maintenance of traditional customs. This shows well in the restriction of luxurious items in dressing included the prohibitions for clothes. Third, they reflected Chosun's toadysm toward China. With the influx of Chinese style of dressing then government even changed the style of uniforms for public officials into that of Chinese resulting in dual styles of dressing. Ying & Yan Theory greatly affected the colors of Korean clothes and reflected toadysm toward China. too. The theory was embodied by prohibition of such colors for clothes as white, gray, and jade green. I reviewed the twelve patterns on Myunpok, Ten-Longivity patterns and Four-Gracious plants patterns in order to analyze the symbolism and thoughts of patterns for clothes. Nansam, Dopo, and Shimui worn by confucian scholars ensures that those clothes bears confucianism and philosopical factors. As shimui was worn by many people it appears in Chosun scholars' studies and a Chinese book called "Yeki". I reviewed the origin, procession, and ornaments of four ceremonial clothes and tried to find out the confucianism in them. First, In Kwanrei (the coming-of-age ceremony) remained ancestor worship and respect for manners. The clothes for this ceremony granted the rights and responsibilities of and adult to the wearer. The royal Kwanreipok had different dresses for each rank. As Samgapok, the crown prince wore Iksunkwan and Konryongpo for the first ritual, Wonryukwan and Kangsapo for the second, and Myunrukwan and Konpok for the third. The rank of the King's grandson was lower than the crown prince's. This example shows that Chosun people respected manners and thought the basic confucianism "God and people are equal." at the Royal court. Second, as Honreipok(wedding gown), the crown prince wore Myunrukwan and Konpok for Daereipok, Wonyukwan and Kangsapo for Napjing and Tongwoo, and Iksunkwan and Konryongpo for Chekbinui. But common people were allowed to wear an official outfit only for wedding in the means of congratulation on the most important day of their life. Wedding gowns which reflected Ying and Yang Theory emphasized the thought that union of a man and a wife is the most important event in life. Third, Sangrei(funeral) was the last ritual of a human being to send off the deceased. The mourning dresses expressed lamentation of the people left behind. Five-Dress-System for each the relative degree of familarity showed the solemnity and formality, which represented the formality of confucianism and ancestor worship. I reviewed the mourning dresses by dividing them into royal, Yangban's, and commons. They were featured by the fact that there was only one style for every walk of life. It is construed that anyone in mourning can wear the same clothes since he feels the same way regardless of his social rank. Fourth, Chereipok(sacrificial rite dresses) had different styles for each social rank. The King wore Myunpok(Kuryumyun and Kujangpok) were recorded to be worn first in the fourth year of King Taecho's ruling. The crown prince wore Palryumyun and Chiljangpok for sacrificial rite dress which was finally settled when King Sejong was in power. Common people wore Dopo, Shimui for the rite dress in the beginning of the Chosun Era and wore Dopo after Japanese invasion of Korea in 1592. In conclusion, confucianism played the main role in ceremonial dress system of Chosun and that was because it emphasized the ethics of action in life, which was different from other religions. It is true that cause-oriented thoughts and Chung myoung chooui in confucianism drove all ceremonies to extreme manners, discriminating the people who belonged to the lower social rank, and resulting in extremly luxurious life style. However, they also created a unique trend and clothes culture in the Chosun Era. I wish that this thesis provieds important information and direction for furthur studies in the future.

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Effect of Epidural Analgesia on the Post-thoracotomy Patient (경막외 진통법이 개흉술후 환자에게 미치는 영향)

  • Lee, Yong-Jai;Shin, Hwa-Kyun;Kim, Sun-Han;Kwon, Oh-Chun;Nam, Chung-Hee;Rho, Jung-Kee;Lee, Kihl-Rho;Kim, Young-Ah;Lee, Jang-Won;Shin, Hyung-Chul;Kim, Il-Ho;Kim, Soon-Im;Kim, Sun-Chong;Park, Wook
    • The Korean Journal of Pain
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    • v.5 no.1
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    • pp.37-43
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    • 1992
  • Postoperative hypoxemia in the absence of hypoventilation occurs more often after thoracic or upper abdominal surgery than lower abdominal operations or surgery on extremities. Although the factors which produce postoperative alveolar collapse have not been fully evaluated, the dominant factor of postoperative hypoxemia is shunt of blood passing collapsed alveoli and the postoperative pain is associated with restriction of depth of breathing, sighing and movement. In 1979, the first successful clinical usage of epidurally administered morphine for control of postoperative pain was reported by Behar and associates. This study was carried out for twenty patients who received posterolateral thoracostomy with bleb resection between May 1990 and May 1991 and who were primary spontaneous recurrent pneumothoraxes under general endotracheal anesthesia. For the relief of post-thoracotomy pain following of the general anesthesia, we selected ten patients as control group which were treated intermittently IM with injection of pethidine(50 mg) according to the conventional method and another ten patients as study group which were managed with thoracic epidural analgesia. The tip of the catheter was inserted to T4-5 epidural space through T12-L1 or L1-2 interspinous region before the induction of the general anesthesia and then the epidural analgesics(0.25% bupivacaine 15 ml+morphine 3 mg) was injected once a day via the catheter until 4 th POD in the study group. The epidural catheters were removed at postoperative 4 th day in study group. Clinical observations were done about vital signs, ABG, tidal volume, FVC and occurence of adverse effects during postoperative 2hr, 8hr, 1st day, 2nd day, 7th day in both groups. The results were as follows; (1) The values of $V_T$ and FVC were significantly improved in study group(85% and 66%) as compared with control group(76% and 61%) during the postoperative 4 day of the epidural analgesia. (2) After the end of the epidural analgesia(7th POD), the values of FVC were improved invertly rather in control group(98%) than study group(84%). It suggested that the reduction of FVC in study group were caused by the raised pain sensitivity following the end of epidural analgesia. (3) The side effects of epidural analgesia such as transient urinary retention(2 cases), itching sensation(1) and headache(1) were noted.

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Comparison of Growth of the Pacific Oysters, Crassostrea gigas, Cultured with Korean and Japanese Spats (한국산 및 일본산 굴, Crassostrea gigas 종패의 성장비교)

  • 정우건;조상만;문수경;정보영
    • The Korean Journal of Malacology
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    • v.17 no.1
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    • pp.19-26
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    • 2001
  • To study the growth of transplanted Pacific oysters, Crassostrea gigas, we sampled Korean and Japanese oysters attached in Chinhae Bay near Gaduk Island and in Seto inland sea in Japan, respectively, suspended in Pukman Bay. Water Temperature ranged from 11.2 to 27.8$^{\circ}C$ (mean 19.84 ${\pm}$ 5.47$^{\circ}C$) on the surface, and 11.1 to 23.6$^{\circ}C$ (mean 18.31 ${\pm}$ 4.18$^{\circ}C$) on the bottom. Salinity ranged from 31.45 to 34.57 (mean 33.10 ${\pm}$ 1.16) on the surface, and from 31.69 to 34.35 (mean 33.24 ${\pm}$ 1.06) on the bottom. salinity was the lowest in September and October, and the highest in December. Growth of oysters in shell height showed a significant difference after being suspended at the farm, reaching 70.3 ${\pm}$ 12.5 mm in the Korean oysters and 96.2 ${\pm}$ 14.6 mm in the Japanese oysters in December. While the Korean oysters showed relatively low growth rate and cessation of growth after sudden growth between June and July, the Japanese oysters showed continuous growth during the whole farming period, although stepwise growth was observed. It was not until September that meat weight showed a significant difference between the two. After September, there was a sudden increase in the Japanese oysters, reaching 7.5 ${\pm}$ 2.9 g in December, but growth of the Korean oysters showed slow growth rate during whole farming period, reaching 4.6 ${\pm}$ 1.9 g in December. here was an obvious decrease in the meat weight of Japanese oysters in December, which might be attributed to restriction of food. Condition factors rebounded in October in the Korean oysters and in September in the Japanese oysters, respectively, attaining 12.8 in the Korean oysters and 15.3 in the Japanese oysters at the end of investigation on December. Shell length-height regression equations were as follows: Korean oysters: S$\sub$h/=2.922S$\sub$t/,-4.8024 (r$^2$= 0.8541) Japanese oysters: S$\sub$t/=3.623S$\sub$h/,-5.1239 (r$^2$=0.7782) This showed the possibility of morphological transformation in the shell of the Korean oysters since shell height was longer than those reported by Bae et al. (1976) and Lee et al. (1992).

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The Utilization Pattern of a Rural Health Subcenter among Suburban Farmhouse Members (일 도시근교 농가구원의 보건지소 이용양상)

  • Sohn, Seok-Joon;Kwon, Sun-Seok;Kim, Sang-Won;Byun, Ju-Nam;Nam, Hae-Sung;Son, Myung-Ho
    • Journal of agricultural medicine and community health
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    • v.24 no.1
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    • pp.65-77
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    • 1999
  • In order to estimate the utilization pattern of a rural health subcenter, and to identify the recognition for it among the farmhouse members in a suburban area, a questionnaire survey was carried out for objects of 696 population. The results observed were as follows: The annual utilization rate of rural health subcenter for a basic health service unit was 25.0 per 100 persons, and annual mean visiting times was 0.22 times. And the most frequent disease by annual health subcenter utilization illness was musculoskeletal disease(30.6%), and the next was respiratory disease(14.1%), gastrointestinal disease(13.9%) by order. Favorite reason for community health subcenter utilization were near distance from living place(49.6%), lower disease severity(18.9%) and lower medical cost(18.1%) by order. But disfavoring reasons for it were absence of specialist(20.2%), non effective treatment(19.2%) and insufficient equipment(14.7%) by order. And insufficient items about community health subcenter utilization were restriction of treatment limit(40.7%), lower reliance(22.5%) and difficulty in traffic(13.4%) by order. The results of logistic regression analysis suggested that statistically significant factors in health subcenter utilization was educational level. The desirable works for the health subcenter in a suburban area were disease control of elderly and disease preventing service. These results suggested that to increase the utilization of rural health subcenter in a suburban area and to promote the accessibility of rural residents to primary health care, there must be considered public relation about health subcenter, improvement of medical quality and change of priority about health subcenter's works.

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Genetic Polymorphism of Epoxide Hydrolase and GSTM1 in Chronic Obstructive Pulmonary Disease (만성폐쇄성폐질환 발생에 Epoxide hydrolase와 GSTM1유전자 다형성의 의의)

  • Park, Sang Sun;Kim, Eun Joung;Son, Chang Young;Wi, Jeong Ook;Park, Kyung Hwa;Cho, Gye Jung;Ju, Jin Young;Kim, Kyu Sik;Kim, Yu II;Lim, Sung Chul;Kim, Young Chul;Park, Kyung Ok;Na, Kook Joo
    • Tuberculosis and Respiratory Diseases
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    • v.55 no.1
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    • pp.88-97
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    • 2003
  • Background : Although smoking is a major cause of chronic obstructive pulmonary disease (COPD), only 10-20% of cigarette smokers develop symptomatic COPD, which suggests the presence of genetic susceptibility. This genetic susceptibility to COPD might depend on variations in the activities of the enzyme that detoxify hazardous chemical products, such as microsomal epoxide hydrolase (mEPHX) and glutathione-S transferase M1 subunit (GSTM1) genes. Methods : The genotypes of 58 patients with COPD, and 79 age matched control subjects, were determined by a polymerase chain reaction, followed by restriction fragment length polymorphism (PCR-RFLP) for the mEPHX, and multiplex PCR for the GSTM1. Results : GSTM1 was deleted in 53.3% of the subjects. There was no difference in GSTM1 deletion rates between the COPD patients (32/58, 55.2%) and the control subjects (41/79, 51.9%). The combination patterns of two polymorphisms of mEPHX showed slow enzyme activity in 29(21.2%), normal in 73(53.3%) and fast in 32(23.4%). The COPD group (7/57, 12.3%) showed a significantly lower incidence of slow enzyme activity compared to the control subjects (22/77, 28.6%, p<0.05). However, when the COPD and control groups were compared with smokers only, there were no significant differences in the genotypes of GSTM1 and mEPHX. Conclusion : The genotypes of GSTM1 and mEPHX were not significant risk factors of COPD in this cohort of study.