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Changing Patterns of Infect ions with Digenetic Larval Trematodes from Fresh-water Fish in River Taega, Gyeongsangbuk-do Province, Korea (경북(慶北) 대가천(大駕川)에서 채집(採集)된 담수어(淡水魚)에 있어서 흡충류(吸蟲類) 피낭유충(被囊幼蟲) 기생상(寄生狀)의 변화(變化))

  • Joo, Kyung-Hwa;Kim, Tae-Hyoung;Joo, Chong-Yoon
    • Journal of agricultural medicine and community health
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    • v.26 no.2
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    • pp.161-179
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    • 2001
  • Recent patterns of infections with digenetic larval trematodes from fresh-water fish were studied in five locations of the river Taega during the period from October, 1998 to September, 2000, and compared with the data reported previously in the same river. The fish were collected using following techniques ; fishing, throwing a castnet, and using a bait of crushed oil cake in a transparent plastic bowl. Of 19 species of fish examined, eight species of encysted larvae, Clonorchis sinensis, Cyathocotyle orientalis, Centrocestus armatus, Clinostomum complanatum, Exorchis oviformis, Metagonimus species, Metacecaria hasegawai, and Metorchs orientalis, and two kinds of undetermined cyst A and C were found. The encysted larvae of Exorchis oviformis were found most frequently from 12 species of fresh-water fish, followed by Metacercaria hasegawai larvae from 9 species, the cyst of Clonorchis sinensis and Cyathocotyle orientalis from 7 species, Centrocestus armatus from 3 species, Clino- stomum complanatum from 2 species, and Metorchis orientalis from 1 species. The infection rates of fish with Clonorchis sinensis larvae were lower than those reported in 1993, whereas their intensity of infection was found lowered in 3 species, Pungtungia herz I, Saurogobio dabry i, and Squalidus jap onicus coreanus. The infection rates and intensity of 6 species of fish with Metagonimus sp ecies larvae were lower than the results in 1993, while the rates in several species of fish with Exorchis oviformis rather higher. The encysted larvae of Cyathocotyle orientalis, Metacercaria hasegawai, and Metorchis orientalis showed variations in infection rates of fish in 1993 and in the present study. However, It was impossible to compare the infection rates for the encysted larvae on the scales, fins and tail as they varied so considerably in both 1993 and 2000 surveys. This study indicate that the rate of infection with digenetic larval trematodes in fresh-water fish was still relatively high in the river Taega, and the metacercarial burden in the fish varies greatly by different fish in 1993.

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Expression of Clusterin in the Salivary Gland under Restraint Stress (구속 스트레스에 의한 타액선 조직내의 Clusterin 발현)

  • Park, Hee-Kyung;Chun, Yang-Hyun;Hong, Jung-Pyo;Auh, Q-Schick
    • Journal of Oral Medicine and Pain
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    • v.33 no.3
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    • pp.247-256
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    • 2008
  • The belief that stress leads to illness has a long history. A number of the orofacial disease are also closely associated with stress. Despite research in the relationship of stress and the orofacial diseases leading to statistically significant correlations, the pathology remains vague. In the present study, the expression of clusterin, a stress protein responsible for antiapoptosis and cytoprotection, under restraint stress condition was observed in the submandibular gland, one of the major salivary glands. Sprague-Dawley rats were divided into 2 groups: normal group and restraint stress group. The rats of restraint stress group were placed in the stress cages and then sacrificed at day 0, 3 and 5 day of the experiment. After that, the submandibular glands of all the rats were excised immediately. The levels of clusterin proteins and mRNA in the tissues were measured by immunohistochemistry and Northern blot analyses, respectively. The results were as follows: 1. In the immunohistochemistry, clusterin protein was detected only immediately after the application of restraint stress. 2. In the restraint stress group, at day 3 and 5, histologically apoptosis was induced with karyorrhectic and pyknotic changes. 3. By the restraint stress, acinic cells were destructed earlier than ductal cells. 4. In the Northern blot, mRNA of clusterin was expressed only immediately after the application of restraint stress. The overall results suggest that as an early response to stress, clusterin is expressed in the glands to protect the glandular cells from the stress. But if stress is so strong and prolonged that it can exceed the stress adaptability of the cells, then the cells may undergo apoptosis instead of producing clusterin. An Epidemiologic Study of Symptoms of Temporomandibular Disorders in Korean College Students.

Analysis of DNA Ploidy with Bronchoscopic Brushing Specimen as A Diagnostic Aid for Lung Cancer (폐암 진단에 있어서 기관지솔질표본의 DNA 배수성 검사의 의의)

  • Kim, Young-Chul;Lee, Shin-Seok;Chung, Ik-Joo;Kang, Yu-Ho;Choi, In-Seon;Park, Kyung-Ok;Juhng, Sang-Woo
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.4
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    • pp.354-362
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    • 1994
  • Objectives and Methods : The presence of aneuploidy or high proliferative activity in cytologic specimens is considered as complementary for the diagnosis of malignancy. To evaluate the diagnostic usefulness of DNA ploidy and cell cycle analysis in lung cancer, we compared the diagnostic yielding rates of DNA ploidy test by brushing specimens using flow cytometry with bronchoscopic forceps biopsy and brushing cytology. Results : Of the seventy-six cases, 55 cases proved to have malignant diseases(squamous cell cancer: 27, adenocarcinoma: 7, large cell cancer: 1, undifferentiated: 4 and small cell cancer: 16). The incidence of aneuploidy in lung cancer patients was 32.7%(18/55), as opposed to no cases in benign disease. And the proportion of high proliferative activity(S+G2M>22%) in lung cancer patients was 42.9%(15/35), but none in benign diseases. In fifty-six of 75 cases(74.7%), cytology of brushing specimens and DNA analysis(either aneuploidy or high proliferative activity vs. diploidy and low proliferative activity) were in concordance. The sensitivity with only brushing cytology was 41.8%(23/55), but with the addition of DNA analysis, it was increased to 56.4%(31/55), without decreasing the specificity(100%). And there was a case whose clue for malignancy was absent except aneuploidy, and he was confirmed to have squamous cell cancer following open thoracotomy. There were no differences in the frequency of aneuploidy or high proliferative activity between histologic subtypes of bronchogenic malignancy. Conclusions : The diagnostic detection rate of lung cancer was improved with the addition of DNA ploidy and cell cycle analysis, and the presence of aneuploidy or high proliferative activity was a relatively specific indicator of malignant disease. It would be useful to test DNA ploidy and cell cycle analysis with brushing specimen for the diagnosis of bronchogenic malignancy particularly in patients whose biopsy specimen could not be obtainable.

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A High Essential Amino Acid Properties Rice Cultivar 'Haiami' (필수아미노산 고함유 신품종 '하이아미')

  • Hong, Ha-Cheol;Kim, Yeon-Gyu;Yang, Chang-Ihn;Hwang, Hung-Goo;Lee, Jeom-Ho;Lee, Sang-Bok;Choi, Yong-Hwan;Kim, Hong-Yeol;Lee, Kyu-Seong;Yang, Sae-Jun;Kim, Myeong-Ki;Jeong, O-Young;Cho, Young-Chan;Jeon, Yong-Hee;Choi, Im-Soo;Jeong, Eung-Gi;Oh, Sea-Kwan;O, Myeong-Gyu;Yea, Jong-Du;Shin, Young-Seoup;Kim, Jeong-Ju
    • Korean Journal of Breeding Science
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    • v.43 no.6
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    • pp.543-548
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    • 2011
  • Haiami is a new Japonica rice variety developed from a cross between 'Jinmibyeo' TR treated with ethyl methane sulfonate (EMS) EMS and 5-methytryptophan, and 'Gyehwabyeo' in order to develop a new premium quality rice variety by a rice breeding team of National Institute of Crop Science, Rural Development Administration in 2008. This variety has about 138 days of growth duration from transplanting to harvesting in central plain area of Korea. The heading date of this vareity was on $15^{th}$, August. The 'Haiami' has good semi-elect plant type and resistant to lodging with strong culm. The number of panicles/hill of 'Haiami' is more than that of 'Hwaseongbyeo'. This variety shows slow leaf senescence and considerable tolerance to viviparous germination. It is susceptible to leaf blast, bacterial blight, and insect pests, but resistance to rice stripe virus. The milled rice of this variety exhibited translucent, clear non-glutinous endosperm and short grain shape. The essential amino acid properties of 'Haiami' have more than 31% that of 'Hwaseongbyeo' in polished rice. This variety has premium palatability of cooked rice. The yield performance of this rice cultivar was about 5.38 MT/ha in milled rice in local adaptability test for three years from 2006 to 2008. 'Haiami' is adaptable to central and southern plain areas of Korea.

How Enduring Product Involvement and Perceived Risk Affect Consumers' Online Merchant Selection Process: The 'Required Trust Level' Perspective (지속적 관여도 및 인지된 위험이 소비자의 온라인 상인선택 프로세스에 미치는 영향에 관한 연구: 요구신뢰 수준 개념을 중심으로)

  • Hong, Il-Yoo B.;Lee, Jung-Min;Cho, Hwi-Hyung
    • Asia pacific journal of information systems
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    • v.22 no.1
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    • pp.29-52
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    • 2012
  • Consumers differ in the way they make a purchase. An audio mania would willingly make a bold, yet serious, decision to buy a top-of-the-line home theater system, while he is not interested in replacing his two-decade-old shabby car. On the contrary, an automobile enthusiast wouldn't mind spending forty thousand dollars to buy a new Jaguar convertible, yet cares little about his junky component system. It is product involvement that helps us explain such differences among individuals in the purchase style. Product involvement refers to the extent to which a product is perceived to be important to a consumer (Zaichkowsky, 2001). Product involvement is an important factor that strongly influences consumer's purchase decision-making process, and thus has been of prime interest to consumer behavior researchers. Furthermore, researchers found that involvement is closely related to perceived risk (Dholakia, 2001). While abundant research exists addressing how product involvement relates to overall perceived risk, little attention has been paid to the relationship between involvement and different types of perceived risk in an electronic commerce setting. Given that perceived risk can be a substantial barrier to the online purchase (Jarvenpaa, 2000), research addressing such an issue will offer useful implications on what specific types of perceived risk an online firm should focus on mitigating if it is to increase sales to a fullest potential. Meanwhile, past research has focused on such consumer responses as information search and dissemination as a consequence of involvement, neglecting other behavioral responses like online merchant selection. For one example, will a consumer seriously considering the purchase of a pricey Guzzi bag perceive a great degree of risk associated with online buying and therefore choose to buy it from a digital storefront rather than from an online marketplace to mitigate risk? Will a consumer require greater trust on the part of the online merchant when the perceived risk of online buying is rather high? We intend to find answers to these research questions through an empirical study. This paper explores the impact of enduring product involvement and perceived risks on required trust level, and further on online merchant choice. For the purpose of the research, five types or components of perceived risk are taken into consideration, including financial, performance, delivery, psychological, and social risks. A research model has been built around the constructs under consideration, and 12 hypotheses have been developed based on the research model to examine the relationships between enduring involvement and five components of perceived risk, between five components of perceived risk and required trust level, between enduring involvement and required trust level, and finally between required trust level and preference toward an e-tailer. To attain our research objectives, we conducted an empirical analysis consisting of two phases of data collection: a pilot test and main survey. The pilot test was conducted using 25 college students to ensure that the questionnaire items are clear and straightforward. Then the main survey was conducted using 295 college students at a major university for nine days between December 13, 2010 and December 21, 2010. The measures employed to test the model included eight constructs: (1) enduring involvement, (2) financial risk, (3) performance risk, (4) delivery risk, (5) psychological risk, (6) social risk, (7) required trust level, (8) preference toward an e-tailer. The statistical package, SPSS 17.0, was used to test the internal consistency among the items within the individual measures. Based on the Cronbach's ${\alpha}$ coefficients of the individual measure, the reliability of all the variables is supported. Meanwhile, the Amos 18.0 package was employed to perform a confirmatory factor analysis designed to assess the unidimensionality of the measures. The goodness of fit for the measurement model was satisfied. Unidimensionality was tested using convergent, discriminant, and nomological validity. The statistical evidences proved that the three types of validity were all satisfied. Now the structured equation modeling technique was used to analyze the individual paths along the relationships among the research constructs. The results indicated that enduring involvement has significant positive relationships with all the five components of perceived risk, while only performance risk is significantly related to trust level required by consumers for purchase. It can be inferred from the findings that product performance problems are mostly likely to occur when a merchant behaves in an opportunistic manner. Positive relationships were also found between involvement and required trust level and between required trust level and online merchant choice. Enduring involvement is concerned with the pleasure a consumer derives from a product class and/or with the desire for knowledge for the product class, and thus is likely to motivate the consumer to look for ways of mitigating perceived risk by requiring a higher level of trust on the part of the online merchant. Likewise, a consumer requiring a high level of trust on the merchant will choose a digital storefront rather than an e-marketplace, since a digital storefront is believed to be trustworthier than an e-marketplace, as it fulfills orders by itself rather than acting as an intermediary. The findings of the present research provide both academic and practical implications. The first academic implication is that enduring product involvement is a strong motivator of consumer responses, especially the selection of a merchant, in the context of electronic shopping. Secondly, academicians are advised to pay attention to the finding that an individual component or type of perceived risk can be used as an important research construct, since it would allow one to pinpoint the specific types of risk that are influenced by antecedents or that influence consequents. Meanwhile, our research provides implications useful for online merchants (both online storefronts and e-marketplaces). Merchants may develop strategies to attract consumers by managing perceived performance risk involved in purchase decisions, since it was found to have significant positive relationship with the level of trust required by a consumer on the part of the merchant. One way to manage performance risk would be to thoroughly examine the product before shipping to ensure that it has no deficiencies or flaws. Secondly, digital storefronts are advised to focus on symbolic goods (e.g., cars, cell phones, fashion outfits, and handbags) in which consumers are relatively more involved than others, whereas e- marketplaces should put their emphasis on non-symbolic goods (e.g., drinks, books, MP3 players, and bike accessories).

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Effects on Storage Property of Fresh Jujube Treated with Grape Fruit Stem Extracts (GFSE) and Fermented Pollen (FP) (포도줄기추출물 및 발효화분 처리가 생대추의 저장기간에 미치는 영향)

  • Woo, Koan-Sik;Hwang, In-Guk;Jang, Keum-Il;Kang, Tae-Su;Lee, Hee-Bong;Jeong, Heon-Sang
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.8
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    • pp.1090-1094
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    • 2008
  • Treatment effects of grape fruit stem extracts (GFSE) containing trans-resveratrol or fermented pollen (FP), and ethylene gas scavenging material (EGS) on the storage property of fresh jujube (Z izyphus jujuba forma hoonensis C.S. Yook) were investigated. Fresh jujubes were packed in different storage containers (PE film and Lock & Lock vessel), and treated with GFSE containing trans-resveratrol of 30 ppm or 1% FP, and EGS. The storage vessels were stored in refrigerator ($0{\pm}1^{\circ}C$) during 12 weeks, and then quality characteristics during storage period were analysed. Hardness slightly increased until 4 weeks and decreased afterward. Soluble solid ($^{\circ}Bx$) and total titratable acidity of fresh jujube slightly increased in all treatments during storage period. Vitamin C content of fresh jujube slightly decreased in all treatments during storage period. Number of microorganisms decreased until 4 weeks and increased afterward. The decay enzyme activity increased in all treatments during storage period. Storage stability was higher for PE film than Lock & Lock containers. Storage period of fresh jujube in this experiment ranges in $8{\sim}9$ weeks for maturity fruits treated with 30 ppm of GFSE and ethylene gas scavenging material.

Improved Social Network Analysis Method in SNS (SNS에서의 개선된 소셜 네트워크 분석 방법)

  • Sohn, Jong-Soo;Cho, Soo-Whan;Kwon, Kyung-Lag;Chung, In-Jeong
    • Journal of Intelligence and Information Systems
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    • v.18 no.4
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    • pp.117-127
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    • 2012
  • Due to the recent expansion of the Web 2.0 -based services, along with the widespread of smartphones, online social network services are being popularized among users. Online social network services are the online community services which enable users to communicate each other, share information and expand human relationships. In the social network services, each relation between users is represented by a graph consisting of nodes and links. As the users of online social network services are increasing rapidly, the SNS are actively utilized in enterprise marketing, analysis of social phenomenon and so on. Social Network Analysis (SNA) is the systematic way to analyze social relationships among the members of the social network using the network theory. In general social network theory consists of nodes and arcs, and it is often depicted in a social network diagram. In a social network diagram, nodes represent individual actors within the network and arcs represent relationships between the nodes. With SNA, we can measure relationships among the people such as degree of intimacy, intensity of connection and classification of the groups. Ever since Social Networking Services (SNS) have drawn increasing attention from millions of users, numerous researches have made to analyze their user relationships and messages. There are typical representative SNA methods: degree centrality, betweenness centrality and closeness centrality. In the degree of centrality analysis, the shortest path between nodes is not considered. However, it is used as a crucial factor in betweenness centrality, closeness centrality and other SNA methods. In previous researches in SNA, the computation time was not too expensive since the size of social network was small. Unfortunately, most SNA methods require significant time to process relevant data, and it makes difficult to apply the ever increasing SNS data in social network studies. For instance, if the number of nodes in online social network is n, the maximum number of link in social network is n(n-1)/2. It means that it is too expensive to analyze the social network, for example, if the number of nodes is 10,000 the number of links is 49,995,000. Therefore, we propose a heuristic-based method for finding the shortest path among users in the SNS user graph. Through the shortest path finding method, we will show how efficient our proposed approach may be by conducting betweenness centrality analysis and closeness centrality analysis, both of which are widely used in social network studies. Moreover, we devised an enhanced method with addition of best-first-search method and preprocessing step for the reduction of computation time and rapid search of the shortest paths in a huge size of online social network. Best-first-search method finds the shortest path heuristically, which generalizes human experiences. As large number of links is shared by only a few nodes in online social networks, most nods have relatively few connections. As a result, a node with multiple connections functions as a hub node. When searching for a particular node, looking for users with numerous links instead of searching all users indiscriminately has a better chance of finding the desired node more quickly. In this paper, we employ the degree of user node vn as heuristic evaluation function in a graph G = (N, E), where N is a set of vertices, and E is a set of links between two different nodes. As the heuristic evaluation function is used, the worst case could happen when the target node is situated in the bottom of skewed tree. In order to remove such a target node, the preprocessing step is conducted. Next, we find the shortest path between two nodes in social network efficiently and then analyze the social network. For the verification of the proposed method, we crawled 160,000 people from online and then constructed social network. Then we compared with previous methods, which are best-first-search and breath-first-search, in time for searching and analyzing. The suggested method takes 240 seconds to search nodes where breath-first-search based method takes 1,781 seconds (7.4 times faster). Moreover, for social network analysis, the suggested method is 6.8 times and 1.8 times faster than betweenness centrality analysis and closeness centrality analysis, respectively. The proposed method in this paper shows the possibility to analyze a large size of social network with the better performance in time. As a result, our method would improve the efficiency of social network analysis, making it particularly useful in studying social trends or phenomena.

A Clinical Study for Promoting Quality Nusing Care in a University Hospital (질적 간호제공을 위한 간호단위 시범 운영 효과에 관한 임상적 연구)

  • Lee, A.J.;Kim, S.H.;Seong, Y.H.;Yoo, S.A.;Kwon, I.G.;Jeong, Y.I.;Nam, H.K.;Kwon, E.J.
    • The Korean Nurse
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    • v.32 no.5
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    • pp.66-77
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    • 1994
  • The purpose of this study was to develop a new nursing unit which can meet changing health care needs, enhance patients' satisfaction and nurses' job satisfaction, and finally guarantee quality nursing care with present manpower. For this, one medical unit was selected as a unit for quality care. And one medical unit which is similar in staffing and patients' characteristics was selected as a control unit. To assess present problems and identify the remedies to the problems a hospital-wide survey and a workshop were performed. According to the survey results, educational programs and improvement of the facilities and equipment supply system, managereal support for interdepartmental cooperation and intensification of bed-side nursing care were adopted as main principles for operating model unit, This model unit was operated for 3 months from Sep. 1, 1992 to Nov. 30, 1992. To evaluate the effectiveness of the model unit, derect/indirect nursing care hours, patients' satisfaction to nursing care, nurses' job satisfaction, and quality care index were measured. Direct/indirect nursing care hours were compared with that of the control unit, and patients' and nurses' satisfaction and quality care index were measured before and after operating model unit and compared with each other. The results of the study were as follows; 1. In the model unit mean direct nursing care hours per cach shift was 146.88 minutes and indirect nursing care hours was 354.72 minutes. The ratio of the direct nursing care hour to indirect nursing hour was 29.6 ; 70.4 and that of the control unit was 26.9 : 73.1. Direct nursing care hour in model unit was longer than that of the control unit. But, the difference was not significant. In subcategories of direct nursing care, the time spent in mobility and exercise, conservation of body temperature, hygiene, and communication and health education were longer than that of the con" trol unit. 2. Indirect nursing care hour in model unit was shorter than that of the control unit. But, the difference was not significant. In subcategories of indirect nursing care, the time spent in drug management and ward arrangement was shorter than that of the control unit. 3. Patients' satisfaction to nursing care was increased significantly after operating the model unit (T=-3.48, P=-0.002) and satisfaction to subcategories of physical comfort measure, psychological cate, and unit management components were significantly higher than before. 4. In the model unit, nurses' total job satisfaction was increased significantly after operating the model unit(Z=2.1004, P=.0357) and satisfaction to subcategory of satisfaction to administration was significantly higher than before (Z=-2.0732, P=.0382). 5. After operating the model unit, quality care index was increased from 89 to 93. With this results, it can be summarized that all the measures tried for quality care, such as educational programs, managereal support for interdepartmental cooperation, and improvement of the equipment and facility provision resulted in partial increase in direct nursing care hours, nurses satisfaction to their job and patients' satisfaction to nursing care. In can be postulated that managereal support and motivation without proper staff supplementation is not enough for increasing direct nursing care hours. And for the enhancement of the level in clinical nursing, and staff supplement must be considered sincerely and the measures for reducing indirect nursing care hours, such as computerization of nursing care activities, improvement of facilities and equipment and facilities supply system, must be instituted in addition.

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Expression of the Ki-67 antigen Using Monoclonal Antibody MIB-1 in Children with Glomerulonephritis (사구체신염에서 MIB-1을 이용한 Ki-67 항원의 발현)

  • Chung, Woo-Yeong;Song, Min-Seop;Kim, Young-Ju
    • Childhood Kidney Diseases
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    • v.2 no.2
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    • pp.104-109
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    • 1998
  • Purpose : The proliferative nuclear antigen Ki-67, present in all cell cycle phases except G0, is a useful marker for the detection of proliferative cells in vivo. MIB I has been found to recognize an antigen in formalin-fixed and wax-embedded material. The aim of this study was to assess the efficacy of MIB-1 expression as a marker of representing the status of mesangial cell proliferation in renal tissues. Methods : Immunohistochemical staining for Ki-67 Ag using monoclonal antibody MIB-1 (Immunotech,505) were performed in 41 renal tissuses which were obtained by percutaneous renal biopsy done between January 1994 and December 1996. Results : In both glomeruli and renal tubules, MIB-1 expression was observed only in 2 of 18 ($11.1\%$) cases of IgA nephropathy, in 2 of the 4 ($50\%$) cases of mebranoproliferative glomerulonephritis, in 4 of the 5 ($80\%$) cases of poststreptococcal glomerulonephritis. But MIB-1 expression was not detected in all cases of minimal lesion and membranous nephropathy. Renal tubules In another 7 cases of IgA nephropathy were MIB-1 positive. Conclusion : MIB-1 expression in renal tissues may relate to the cell proliferation in glomeruli and renal tubules. But the efficacy of MIB-1 expression as a marker of mesangial cell proliferation may reveal a limited value because of it's lower positive rate in IgA nephropathy.

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대구지역 대기환경용량평가에 관한 연구

  • Choe, Geun-Sik;Kim, Hae-Dong
    • 한국지구과학회:학술대회논문집
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    • 2010.04a
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    • pp.90-91
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    • 2010
  • 우리나라는 산업화와 도시화의 급속한 발전으로 인한 대기오염물질배출시설, 자동차 통행량, 에너지 사용량의 증가 등으로 대기오염물질배출원의 수와 규모가 증대되어 광역도시를 중심으로 대기질이 악화되고 있다. 특히 우리나라의 수도권대기질은 선진국의 주요 도시에 비해 대기오염 상태가 좋지 않은 것으로 평가됨에 따라 정부는 대기질을 OECD선진국 수준으로 개선한다는 목표를 세우고 있으나, 지역의 대기상태 및 그 동안의 대기질 개선을 위해 이행된 정책의 효율성 측면에서 볼 때 사후적인 규제위주의 농도규제 방식으로는 급증하는 대기오염배출시설의 배출량총량 관리가 어렵고, 지자체별로 개별적인 분산관리로는 광역적으로 이동되는 대기오염물질의 관리가 불가능하다. 또한 대기오염과 상관성이 큰 에너지정책, 산업정책, 도시계획 등 관련 정책과의 통합적 접근이 어렵기 때문에 사전에 이를 예방하는 총량관리가 요구되어 진다. 총량규제란 특정지역의 기상, 지형조건 등을 이용하여 대기환경용량을 산출하고 이를 기초로 지역별 배출허용총량을 할당하여 궁극적으로는 오염원별로 대상오염물질의 삭감량을 정하는 제도로 선진국에서는 대기환경용량을 바탕으로 1970년대부터 사업장을 중심으로 배출농도 규제와 함께 총량규제를 병행 실시하고 있으며, 최근에는 자동차에도 실시하고 있다. 우리나라에서도 대기환경보전법 제9조에서 환경기준을 초과하여 사람의 건강이나 재산, 동식물의 생육에 중대한 위해를 가져올 우려가 있다고 인정되는 경우에는 동 지역 또는 특별대책지역 중 사업장이 밀집되어 있는 구역에 대하여 배출되는 오염물질을 총량으로 규제할 수 있도록 규정하고 있다. 또한, 환경부는 2003년도에 서울, 인천, 경기도내 19개시 지역을 대상으로 대기오염물질의 배출총량을 관리하는 대기오염총량제 실시를 포함한 '수도권대기질개선에관한특별법'을 제정하였고, 현재는 사업장에게 연도별 배출허용총량을 할당하고, 할당량 이내로 오염물질을 배출하도록 관리하는 사업장 대기오염물질총량관리 제도로 시행 중에 있다. 그러나 수도권대기질개선특별대책을 수립하면서 총량관리의 본격 이행 및 배출권 거래제도 도입에 대한 특별법안이 제정되고 부분적으로 시행되고 있으나, 우리나라에 총량관리를 본격 이행하는데 있어서의 필요한 준비여건은 아직 초기 단계이고, 관련 연구의 수행실적 또한 수도권에 제한되어 적은 편이다. 따라서 현재는 총량관리가 수도권에 국한하여 실시되고 있으나, 점차 타 도시까지 광역적으로 확대될 것으로 예상되는 바 이에 필요한 제반 사항들에 대한 조사 분석을 통하여 정책방향을 설정하는 더 많은 연구가 필요할 것이다. 이러한 배경에서 본 연구에서는 대구지역을 대상으로 대기오염농도 및 대기오염물질 배출량에 대한 현황조사를 실시하고, 이를 토대로 고농도가 자주 발생되거나 그러할 가능성이 높은 $NO_X$을 대상으로 대기오염기여도를 평가하고 대기확산모델을 통한 대기환경용량을 산정하였다. 대기오염농도 현황을 살펴본 결과, 대구지역의 대기오염은 $NO_2$, $SO_2$, CO는 전형적인 1차오염물질의 변화경향을 보였으며, $PM_{10}$는 봄철에 황사의 영향을 크게 받는 것으로 나타나 실제 대구지역에서 배출되는 양을 추정하기 힘든 것으로 판단된다. 또한 $NO_2$는 공업, 상업지역에서 $SO_2$$PM_{10}$는 공업지역, CO는 상업지역, $O_3$은 교외지역에서 높은 농도를 나타내는 것으로 파악되었다. 대구지역의 대기오염물질 배출량 현황은 CO가 47%, NOX가 43%로 전체 배출량의 90%를 차지하였고, 2005년 이후 $NO_X$는 감소하고 $SO_X$가 증가하는 추세이다. 또한 배출원대분류 중도로 및 비도로이동오염원에서 발생되는 선 오염원이 75%로 대구지역에서 가장 크게 기여하는 것으로 나타났다. ISCST3 대기확산모델을 이용하여 대기환경용량을 산정하기위하여, 먼저 대구지역의 대기환경용량평가는 가시적인 위해성이 높고 개선정책이 용이한 $NO_X$을 대상물질로 선정하였고, 배출량과 오염농도간의 상관도가 0.659로 높은 것으로 판단되어, 배출량을 삭감하였을 때 대기오염농도의 개선이 명확히 나타나는 것을 알 수 있었다. 다음으로, 단위격자 당 한계배출율을 알아내는 작업을 실시하여, 대구지역을 동일하게 장기환경기준 80%수준인 22.4ppb를 만족시키기 위한 한계배출율은 2.23g/s가 필요한 것으로 파악되었고, 산출한 한계배출율을 이용하여 장기환경기준치 80%수준 달성을 목표로 하는 경우의 대기환경용량을 산정하고 실제 배출량과 비교 분석하였다. 그 결과, 대구지역 전체의 환경용량은 약 3만 톤으로 실제 배출량 2만2천 톤에 약 8천 톤 이상의 여유가 있는 것으로 파악되었다. 그러나 구역별로 상이한 차이를 보였으며, 이에 따른 구역별 개선정책이 필요할 것으로 사료된다. 대기환경용량을 파악한 후 단위격자 당 한계배출율을 초과하는 대상 지역을 추출하여 삭감한 결과 초과배출량의 80%를 삭감해야 대구지역 전체에서 50ppb이하 농도가 되는 것을 알 수 있었는데, 실제로 초과배출량의 80%를 삭감하는 것은 어려움이 있다고 판단되어, 대구지역을 동일한 %율로 삭감한 결과 30% 삭감했을 때 50ppb수준을 달성하였고, 50%삭감했을때 2007년 환경기준인 30ppb수준을 달성하였다. 또한 배출원대분류 중 기여율이 높은 도로와 비도로오염원을 50%삭감한 결과 도로이동오염원의 삭감만으로도 상당한 고 배출지역의 농도저감에 효과가 있는 것으로 파악되고, 비도로오염원을 포함하여 삭감하였을 때는 대구지역 전체에서 50ppb이하로 내려가는 것을 볼 수 있었다. 따라서 향후 총량규제의 실시에 맞추어 대구지역의 실제적인 환경용량의 정확한 파악과 고배출지역에 대한 삭감방법에 관한 더 많은 연구가 필요하다고 사료된다. 이 연구 결과는 앞으로 시행될 지역총량규제에 대한 기초적인 방법론으로 활용될 수 있을 것이다.

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