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집단지성의 품질, 그 결정요인, 유용성의 관계: 수용자 관점에서 한국의 위키서비스와 Q&A 서비스의 비교 (Relationships between Collective Intelligence Quality, Its Determinants, and Usefulness: A Comparative Study between Wiki Service and Q&A Service in Perspective of Korean Users)

  • 주재훈;이스마틸라 노르마토프
    • Asia pacific journal of information systems
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    • 제22권4호
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    • pp.75-99
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    • 2012
  • Innovation can come from inside or outside organizations. Recently, organizations have begun turning to external knowledge more often, through various forms of collective intelligence (CI) as collaborative platform to solve complex problems. Several factors facilitate this CI utilization phenomenon. First, with the rapid development of Internet and social media, numerous web applications have become available to millions of the Internet users over the past few decades. Web 2.0 and social media have become innovative web applications that provide an environment for human social interaction and collaboration. Second, the diffusion of simple and easy-to-use technologies that enable users to interact and design web applications without programming skills have led to vast, previously unknown amounts of user-generated content. Finally, the Internet has enabled communities to connect and collaborate, creating a virtual world of CI. In this study, web enabled CI is defined as a composed ability of individuals who are acting as a single cognitive unit to achieve common goals, think reasonably, solve problems, make decisions, carry out complex tasks, and develop creative ideas collectively through participation and collaboration on the web. Although CI plays a critical role in organizational innovation and collaboration, the dubious quality of CI is still problem that is difficult to solve. In general, the quality level of content collected from the crowd is lower than that from professionals. Thus, it is important to identify determinants of CI quality and to analyze the relationship between CI quality and its usefulness. However, there is a lack of empirical study on the quality factors of web-enabled CI. There exist a variety of web enabled CI sites such as Threadless, iStockphoto or InnoCentive, Wikipedia, and Youtube. One of the most successful forms of web-enabled CI is the Wikipedia online encyclopedia, accessible all over the world. Another one example is Naver KnowledgeiN, a typical and popular CI site offering question and answer (Q&A) services. It is necessary to study whether or not different types of CI have a different effect on CI quality and its usefulness. Thus, the purpose of this paper is to answer to following research questions: ${\bullet}$ What determinants are important to CI quality? ${\bullet}$ What is the relationship between CI quality factors and the usefulness of web-enabled CI? ${\bullet}$ Does CI type have a moderating effect on the relationship between CI quality, its determinants, and CI usefulness? Online survey using Google Docs with email and Kakao Talk was conducted for collecting data from Wikipedia and Naver KnowledgeiN users. A totoal of 490 valid responses were collected, where users of Wikipedia were 220 while users of Naver KnowledgeiN were 270. Expertise of contributors, community size, and diversity of contributors were identified as core determinants of perceived CI quality. Perceived CI quality has significantly influenced perceived CI usefulness from a user's perspective. For improving CI quality, it is believed that organizations should ensure proper crowd size, facilitate CI contributors' diversity and attract as many expert contributors as possible. Hypotheses that CI type plays a role of moderator were partially supported. First, the relationship between expertise of contributors and perceived CI quality was different according to CI type. The expertise of contributors played a more important role in CI quality in the case of Q&A services such as Knowledge iN compared to wiki services such as Wikipedia. This implies that Q&A service requires more expertise and experiences in particular areas rather than the case of Wiki service to improve service quality. Second, the relationship between community size and perceived CI quality was different according to CI type. The community size has a greater effect on CI quality in case of Wiki service than that of Q&A service. The number of contributors in Wikipeda is important because Wiki is an encyclopedia service which is edited and revised repeatedly from many contributors while the answer given in Naver Knowledge iN can not be corrected by others. Finally, CI quality has a greater effect on its usefulness in case of Wiki service rather than Q&A service. In this paper, we suggested implications for practitioners and theorists. Organizations offering services based on collective intelligence try to improve expertise of contributeros, to increase the number of contributors, and to facilitate participation of various contributors.

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상황인식 기반 지능형 최적 경로계획 (Intelligent Optimal Route Planning Based on Context Awareness)

  • 이현정;장용식
    • Asia pacific journal of information systems
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    • 제19권2호
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    • pp.117-137
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    • 2009
  • Recently, intelligent traffic information systems have enabled people to forecast traffic conditions before hitting the road. These convenient systems operate on the basis of data reflecting current road and traffic conditions as well as distance-based data between locations. Thanks to the rapid development of ubiquitous computing, tremendous context data have become readily available making vehicle route planning easier than ever. Previous research in relation to optimization of vehicle route planning merely focused on finding the optimal distance between locations. Contexts reflecting the road and traffic conditions were then not seriously treated as a way to resolve the optimal routing problems based on distance-based route planning, because this kind of information does not have much significant impact on traffic routing until a a complex traffic situation arises. Further, it was also not easy to take into full account the traffic contexts for resolving optimal routing problems because predicting the dynamic traffic situations was regarded a daunting task. However, with rapid increase in traffic complexity the importance of developing contexts reflecting data related to moving costs has emerged. Hence, this research proposes a framework designed to resolve an optimal route planning problem by taking full account of additional moving cost such as road traffic cost and weather cost, among others. Recent technological development particularly in the ubiquitous computing environment has facilitated the collection of such data. This framework is based on the contexts of time, traffic, and environment, which addresses the following issues. First, we clarify and classify the diverse contexts that affect a vehicle's velocity and estimates the optimization of moving cost based on dynamic programming that accounts for the context cost according to the variance of contexts. Second, the velocity reduction rate is applied to find the optimal route (shortest path) using the context data on the current traffic condition. The velocity reduction rate infers to the degree of possible velocity including moving vehicles' considerable road and traffic contexts, indicating the statistical or experimental data. Knowledge generated in this papercan be referenced by several organizations which deal with road and traffic data. Third, in experimentation, we evaluate the effectiveness of the proposed context-based optimal route (shortest path) between locations by comparing it to the previously used distance-based shortest path. A vehicles' optimal route might change due to its diverse velocity caused by unexpected but potential dynamic situations depending on the road condition. This study includes such context variables as 'road congestion', 'work', 'accident', and 'weather' which can alter the traffic condition. The contexts can affect moving vehicle's velocity on the road. Since these context variables except for 'weather' are related to road conditions, relevant data were provided by the Korea Expressway Corporation. The 'weather'-related data were attained from the Korea Meteorological Administration. The aware contexts are classified contexts causing reduction of vehicles' velocity which determines the velocity reduction rate. To find the optimal route (shortest path), we introduced the velocity reduction rate in the context for calculating a vehicle's velocity reflecting composite contexts when one event synchronizes with another. We then proposed a context-based optimal route (shortest path) algorithm based on the dynamic programming. The algorithm is composed of three steps. In the first initialization step, departure and destination locations are given, and the path step is initialized as 0. In the second step, moving costs including composite contexts into account between locations on path are estimated using the velocity reduction rate by context as increasing path steps. In the third step, the optimal route (shortest path) is retrieved through back-tracking. In the provided research model, we designed a framework to account for context awareness, moving cost estimation (taking both composite and single contexts into account), and optimal route (shortest path) algorithm (based on dynamic programming). Through illustrative experimentation using the Wilcoxon signed rank test, we proved that context-based route planning is much more effective than distance-based route planning., In addition, we found that the optimal solution (shortest paths) through the distance-based route planning might not be optimized in real situation because road condition is very dynamic and unpredictable while affecting most vehicles' moving costs. For further study, while more information is needed for a more accurate estimation of moving vehicles' costs, this study still stands viable in the applications to reduce moving costs by effective route planning. For instance, it could be applied to deliverers' decision making to enhance their decision satisfaction when they meet unpredictable dynamic situations in moving vehicles on the road. Overall, we conclude that taking into account the contexts as a part of costs is a meaningful and sensible approach to in resolving the optimal route problem.

섬유근통 환자에 대한 Milnacipran과 Pregabalin 약물치료에 대한 기능적 자기공명영상에서의 후속 영향 비교 (Comparison of the Medication Effects between Milnacipran and Pregabalin in Fibromyalgia Syndrome Using a Functional MRI: a Follow-up Study)

  • 강민재;문치웅;이영호;김성호
    • Investigative Magnetic Resonance Imaging
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    • 제18권4호
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    • pp.341-351
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    • 2014
  • 목적 : 섬유근통 증후군의 치료에 주로 쓰이는 두 계열의 약물인 Milnacipran (이하 MLN)과 Pregabalin (이하 PGB)의 환자 투여에 따른 약물 치료 효과를 뇌 활성도 변화의 비교 분석을 통해 비교하였다. 대상 및 방법 : 섬유근통 증후군 환자 20명을 대상으로 진행하였으며 20명의 환자 중 약물 치료 군에 따라 MLN 치료군 10명과 PGB 치료군 7명으로 분류하였다. 모든 환자군은 섬유근통 증후군 이외의 요인을 배제하기 위해 정신건강 의학과적 평가를 통해 선별된 후 섬유근통 진단을 위한 임상적 평가가 진행 되었다. 기능적 자기공명영상의 촬영 시 엄지손가락에 블록 형태의 압통 자극을 가해 주었고 영상은 약물 치료 전과 약물 치료 후에 각각 획득하였다. 영상 획득 후 일련의 전처리 과정을 거쳐 약물 치료 전후의 자기공명 혈중산소치의존 (Blood Oxygen Level Dependent, 이하 BOLD) 신호 비교를 위한 대응표본 t-검정과 두 표본 t-검정을 실시 하였다. 결과 : 임상적 평가에 있어 약물 치료 전에는 두 그룹간에 유의한 차이가 나지 않았으며 약물 치료 후 전신통증지수 (Widespread Pain Index, WPI)와 대상자 스스로 피로도를 평가하는 검사 (Brief Fatigue Inventory, BFI)에서 PGB군에 유의한 수준으로 낮게 나타났다. 기능적 영상 분석에 있어 약물 치료 후의 영상 비교 결과 앞 띠이랑과 대뇌섬을 포함한 영역에서 PGB군이 높은 활성도를 보였다. 또한 약물 치료 전후 효과 비교에서는 MLN군에서 대뇌섬, 시상을 포함한 영역에서 치료 후 BOLD 신호가 감소하는 경향을 볼 수 있었지만 PGB군에서는 MLN에 비해 감소된 영역의 수와 크기가 비교적 작게 나타났다. 결론 : 전체 결과에서 두 치료군 모두 증상이 호전되는 경향을 나타냈으나 임상적 평가와 기능적 영상 평가에서 서로 다른 경향을 나타내었다. 이는 두 약물 치료 기전과 세부 치료 목적이 다르고, 전체 환자 수의 부족으로 인한 임상적 평가와의 낮은 상관관계에 의한 영향으로 보이며 이러한 영향을 최소화 시킨다면 두 약물 간의 정확한 치료 효과 비교를 할 수 있을 것으로 예상된다.

영지 균주별 생육특성, 생리활성, 영양성분 및 당 성분 함량 비교 (Comparisons of growth characteristics, biological activities, nutritional contents, and sugar contents of Ganoderma spp. strains)

  • 안기홍;한재구;조재한
    • 한국버섯학회지
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    • 제18권3호
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    • pp.221-233
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    • 2020
  • 본 연구에서는 국내외에서 수집한 영지 유전자원에 대한 평가를 위하여 균주별 생육특성을 분석하였고, 영지의 항산화 활성과 관련이 있는 생리활성 성분, 베타글루칸 함량, 필수 및 비필수 아미노산 성분, 단당류, 이당류 및 당알콜 등의 당 성분 함량을 분석하였다. 14종의 영지 중 갓의 크기, 수확량 등을 고려하여 생육특성이 우수한 균주는 KMCC02960 (G. meredithae), KMCC02932 (G. tropicum)이었다. 14종의 영지 70% 에탄올 추출물 1 mg/ml 농도에서의 DPPH 라디컬 소거능은 53.1% ~ 79.4%를 나타냈으며, 그 중에서 KMCC02932 (G. tropicum) 균주가 가장 높은 소거활성을 나타냈으며, 아질산염 소거능은 영지1호인 KMCC02824 (G. lucidum)와 KMCC02852 (G. neo-japonicum)가 각각 69.5%와 63.2%로 높은 소거활성을 보였다. 총 폴리페놀의 함량은 영지1호인 KMCC02824 (G. lucidum)와 KMCC02852 (G. neojaponicum)가 각각 38.0 mg GAE/g와 37.8 mg GAE/g로 다른 균주에 비하여 높은 함량치를 보였다. 14종의 영지 중에서 높은 베타글루칸 함유량을 보이는 균주는 32.95%의 KMCC02852 (G. neo-japonicum)와, 33.43%의 KMCC03018 (G. lingzhi)이었다. 4종류의 단당류와 2종류의 이당류, 4종류의 당알콜류 분석결과, 모든 성분이 검출된 영지 균주는 KMCC02996 (G. weberianum)과 KMCC03018 (G. lingzhi)이었으며, 총 아미노산과 총 필수아미노산 함량이 높은 균주는 KMCC02932 (G. tropicum)로 티로신(Tyr), 페닐알라닌(Phe) 성분함량이 높게 검출되었으며, 균주별로 성분함량 차이가 있었으나 시스테인(Cys), 티로신(Tyr), 페닐알라닌(Phe) 성분이 다른 성분에 비하여 높게 검출되었다. 위와 같은 결과를 바탕으로 우수 유전자원을 선발하는데 기초자료로서의 활용도가 높으리라 기대되며, 추후 영지 고유의 유용성분인 가노데릭산(ganoderic acid) 등의 분석을 통하여 기능성 소재에 관한 연구를 진행하려 한다.

방사성동위원소옥소(放射性同位元素沃素)($^{131}I$)의 치료량(治療量)이 갑상선종환자(甲狀腺腫患者)의 혈액상(血液像)에 미치는 영향(影響)에 관(關)한 연구(硏究) (A study on the Hematologic Effects of Radioactive Iodine($^{131}I$) Therapy on Various Thyroid Diseases)

  • 김명재;김노경;이정상;최근출;이영우;김기원;강신일
    • 대한핵의학회지
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    • 제3권1호
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    • pp.51-58
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    • 1969
  • To clarify the hematologic effects of the radioiodine ($^{131}I$) in therapeutic doses ($5{\sim}10$ mCi) on the various thyroid patients, authors studied the peripheral blood pictures of 396 goitrous patients before and after radioiodine ($^{131}I$) administrations in the Isotope Clinic of Seoul National University Hospital. Among these 396 cases of goiters, we gave 5 to 10 mCi of radioiodine ($^{131}I$) with single or fractionated administrations. The blood pictures of peripheral blood were repeated after 3 months in 40 cases of 65 cases who had been treated with $^{131}I$. The blood pictures of non-treated thyroid patients were compared with that of normal Korean values to clarify any difference between normal and goiter. The blood pictures of hyperthyroid patients treated with $^{131}I$ therapy were compared with the blood pictures of non-treated thyroid patients. The results were as following: 1) The incidence according to type: Toxic diffuse goiter: 35.4% Nontoxic nodular goiter: 29.7% Euthyroid: 13.8% Nontoxic diffuse goiter: 12.6% Hypothyroidism: 4.3% Thyroiditis($\bar{s}$ subacute form): 1.8% Toxic nodular goiter: 1.4% Malignancy: 1.0% 2) Age incidence: The range of distribution was 11 to 71 years. The peak incidence was found in the 4th decade of life. $80.6{\sim}82.6%$ of those 396 cases were found among the 3rd, 4th and the 5th decades of life. 3) Sex incidence: Sex ratio of male:female was 1:7.8. 4) The most outstanding findings in peripheral blood before treatment were decreased erythrocyte count and hemoglobin value in all types of thyroid diseases, especially in. the cases of hypothyroidism and thyroiditis. Hook worm-infested patients showed no significant difference in erythrocytes and hemoglobin values from those of other hook worm free patients. 5) Total leukocytes count was within normal range. Differential count of W.B.C. showed increased percentile of lymphocyte in diffuse toxic goiter and thyroiditis. 6) 39 cases of diffuse goiter treated with $^{131}I$ toxic showed amelioration in the anemia and restoration to normal range of lymphocyte count in association with increased percentile of neutrophiles 3 months after administration, except a case of toxic nodular goiter. One can observe anemia in slight degree, and increased lymphocytes count in hypothyroidism. Therapeutic dose of radioiodine ($^{131}I$) does not result any residual effect on the hematopoietic function. Radioiodine ($^{131}I$) therapy resulted in improvement of thyroid function in association of amelioration of pevious abnormal blood pictures. 7) Authors did not observe any myxedema resulted from radioiodine therapy during the 3 months period in this study.

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알쯔하이머형 치매환자에서 SPM 방법을 이용한 뇌 관류 SPECT와 정신-인지기능 수행성능의 상관 (Relationship between Brain Perfusion SPECT and MMSE Score in Dementia of Alzheimer's Type: A statistical Parametric Mapping Analysis)

  • 강혜진;이동수;강은주;이재성;여정석;김진영;이동우;조맹제;정준기;이명철
    • 대한핵의학회지
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    • 제36권2호
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    • pp.91-101
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    • 2002
  • 목적: 본 연구의 목적은 첫째, 알쯔하이머형 치매의 국소뇌혈류량이 일정 시간이 지난 후 감소되는 양상을 voxel based 분석을 통해 확인하고자 하였다. 둘째, 이들 환자에 있어서 두뇌 특정부위가 임상에서 흔하게 쓰이는 간이정신상태검사인 MMSE-K(Mini-Mental State Examination, Korean version)의 수행과 상관을 보이는 영역이 있는지 살펴보고자 하였다. 대상 및 방법: Tc-99m HMPAO SPECT를 이용해서 9명의 probable 알쯔하이머형 치매 환자군에게 평균 1.8년의 기간을 두고 각각 두 번의 영상(기저영상과 추적검사 영상)을 얻었고, 이를 각각 9명의 정상노인으로부터 얻은 영상과 비교 분석하였다. 각 영상은 공간정규화 이후 소뇌의 활성화에 따라 계수 정규화되었고, SPM99를 사용하여 voxel based 분석을 하였다. 결과: 대조군에 비하여 환자군에서 뇌혈류량의 감소를 보이는 영역이, 기저검사에서 주로 두정측두영역인데 비하여 추적검사시에는 전두엽 영역으로 확대되었다. MMSE-K 점수와 가장 높은 상관관계를 보이며 뇌혈류가 감소하는 영역은 기억의 부호화와 관련된다고 알려진 좌측 중/하전두엽과 중측두엽, 그리고 후대상회와 전설소엽이었다. 결론: probable 알쯔하이머형 치매 환자군에게 있어서 질병이 진전됨에 따라 변하는 뇌혈류 감소가 두정엽에서 전두엽을 포함하였다. 특히 좌측전두엽의 혈류량 감소는 MMSE-K로 측정된 인지기능 수행 저하와 유의미한 상관을 보임이 확인되었다. 본 연구는 SPM을 이용한 이러한 분석방법을 통하여 핵의학 영상을 알쯔하이머형 치매의 경과추적과 진단의 유용한 도구로 사용할 수 있음을 보인다.

아산화질소에 의한 점진적 저산소가스 흡입이 혈중 가스치와 Catecholamine치 및 혈역학에 미치는 영향 (Changes of Blood Gases, Plasma Catecholamine Concentrations and Hemodynamic Data in Anesthetized Dogs during Graded Hypoxia Induced by Nitrous Oxide)

  • 김세연;송선옥;배정인;전재규;배재훈
    • Journal of Yeungnam Medical Science
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    • 제15권1호
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    • pp.97-113
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    • 1998
  • 교감신경계는 광범위한 각종 기능의 항상성 조절에 결정적인 역할을 하고 있으며, 저산소증, 출혈, 통증 등에 따른 스트레스 반응에 의해 자극되어 심박출량의 증가 및 조직으로 산소공급 향상을 위한 혈류 조절 반응이 나타나게 되나 주어진 환경에 따라 반응 정도는 다양하게 보고되고 있다. 고농도의 $N_2O$로 인해 발생된 저산소혈증 상태에서 혈역학적 변화가 저산소혈증을 발견하는 지표로서 유용한 지를 관찰하기 위해 본 실험에서는 마취후 기계적 환기를 시행한 한국산 잡견에서 고농도의 $N_2O$를 이용하여 흡입산소농도를 점진적으로 감소시킬 때 발생된 저산소혈증이 혈중 catecholarnine의 분비와 혈액 가스 및 혈역학적 변화를 비교 관찰하였다. Halothane으로 흡입 마취하여 기계적 환기를 시행한 뒤 10 마리의 한국산 잡견에서 21%, 15%, 10%, 5%의 산소를 5분씩 공급하여 혈역학상의 변화와 조직의 산소이용 상태 및 혈중 catecholamine치를 관찰하여 다음과 같은 결과를 얻었다. 조절호흡의 결과, 실험견은 등탄산성 저산소혈증이 초래되었으며 흡입산소농도의 감소 정도에 따라 동맥혈 및 혼합정맥혈의 산소분압 및 포화도가 감소되었고, 산소섭취율이 증가함에 따라 동정맥혈 산소함량의 차이는 증가하였으며 동시에 심박출량이 증가하는 대상성 반응을 보였다. 중심 정맥압은 10%와 5%의 흡입산소농도에서 측정치가 유의하게 증가되었고, 평균 폐동맥압은 10%와 5%의 흡입산소농도에서 각각 55% 및 82% 증가되었으며 폐혈관저항도 각각 76%, 95%로 유의하게 증가되었으나 전신혈관저항의 변화는 유의성이 없었다. 실험견에서 혈중 norepinephrine, epinephrine 및 dopamine의 대조치는 각각 $141.4{\pm}94.4$ pg/ml, $172.6{\pm}130.1$ pg/ml, $151.1{\pm}282$ pg/ml이었다. 15% 산소 흡입 시 norepinephrine, epinephrine 및 dopamine치는 모두 유의한 증가를 나타내기 시작하였고 dopamine은 10% 흡입산소농도에서 가장 많이 증가하였으나 5% 흡입산소농도에서는 오히려 감소되었고 60%의 흡입산소로 재산소화하는 동안 대조치 수준으로 회복되었다. 이에 비해 norepinephrine은 15%의 흡입 산소농도에서 74% 증가한 후 저산소혈증이 심화될수록 더욱 증가하는 양상이 계속되었다. Epinephrine은 대조치에 비해 15% 산소 흡입시 29% 증가하였으나 10% 및 5% 흡입산소농도에서 각각 382%, 350% 증가되었다. 60%의 흡입산소로 재산소화하였을 때는 norepinephrine과 epinephrine치는 감소되었으나 대조치보다는 여전히 증가되어 있었다. 이상의 결과로 볼때 마취후 고농도의 $N_2O$에 의한 저산소 가스 흡입은 혈중 catecholamine의 농도를 증가시키나 심혈관계 및 교감 신경계의 반응을 매우 둔화시키는 것으로 생각된다. 따라서 임상 마취에서 환자에게 고농도의 $N_2O$를 흡입시켜 저산소혈증이 초래되는 경우 혈압 및 맥박수의 변화는 저산소혈증을 발견하는 지표로 유용하지 않은 것으로 사료된다.

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VISX 20/20B $VisionKey^{TM}$ 엑시머레이저의 version 4.01 software를 이용한 근시교정술 및 근시성난시교정술의 임상성적 비교 (Comparison of Clinical Results of Excimer Laser Correction of Myopia and Compound Myopic Astigmatism Using VISX 20/20B $VisionKey^{TM}$)

  • 이상범;배상복
    • Journal of Yeungnam Medical Science
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    • 제17권1호
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    • pp.55-65
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    • 2000
  • VISX 엑시머레이저 굴절교정각막절제술의 경우 근시는 다영역 단연마법(Multi-zone, Single pass Ablation)으로, 근시성난시는 타원형 방식(Elliptical mode)에 의해 교정하는 원리를 채택하고 있다. VISX 20/20B $VisionKey^{TM}$ 엑시머레이저의 version 4.01 software를 이용하여 시술한 근시교정술(PRK)과 근시성난시교정술(PARK)의 임상성적에 차이가 있는지 알아보고자 하였다. 1995년 3월부터 1996년 12월까지 엑시머레이저 굴절교정각막절제술을 시행하고 술후 1년까지 경과관찰이 가능했던 PRK 152안, PARK 203안을 대상으로 후향적 연구를 시행하였다. 나안시력, 교정시력, 굴절력, 안압, 각막 혼탁, 각막지형도 등을 술후 1, 3, 6 및 12개월에 검사하였으며, 모든 환자는 12개월 이상 경과 관찰하였다. 술후 1년에 나안시력이 0.7 이상인 경우가 -7D 미만의 PRK군(110안)에서 94.8%, PARK군(104안)에서 88.1%이었고, -7D 이상의 PRK군(31안)에서 86.1%, PARK군(57안)에서 67.1%이었다. 예측도가 ${\pm}1D$ 이내인 경우가 PRK 및 PARK에 따라 -7D 미만에서 97.4%, 93,2%이었고, -7D이상에서는 각각 80.6%, 70.6%이었다. 본 연구에서 종전의 보고된 연구 결과들에 비해 나안시력 개선 및 예측도 등에서 상대적으로 우수한 성적을 나타내었음을 알 수 있었다. 대부분의 근시와 근시성난시는 VISX 20/20B $VisionKey^{TM}$ 엑시머레이저를 이용하여 효과적으로 치료할 수 있었고 PARK에서도 PRK와 유사한 정도의 우수한 성적을 얻었으나, PRK에 비해 보다 정확한 중심잡기와 축정렬 등의 중의가 요망된다. 향후 멕시머레이저와 소프트웨어의 발전에 의해 두 군 모두에서 성적향상을 기대할 수 있으리라 생각된다.

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Effect of Protein Supplementation, O2 Concentration and Co-Culture on the Development of Embryos Produced by Nuclear Transfer Using Cultured Cumulus Cells in Hanwoo (Korean Cattle)

  • Im, G.S.;Yang, B.S.;Park, S.J.;Im, S.K.;Yang, B.C.;Yi, Y.J.;Park, C.S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권9호
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    • pp.1260-1266
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    • 2001
  • The effect of protein supplementation, $O_2$ concentration and co-culture on the development of embryos produced by nuclear transfer using cultured cumulus cell was investigated. Recipient oocytes and cumulus cells were obtained from the ovaries of the slaughtered Hanwoo cows. Donor cumulus cells were cultured in Dulbecco's modified Eagle medium containing 10% fetal bovine serum at 5% $CO_2$ in air at $38.5^{\circ}C$. The 1 to 6 passages of cumulus cells were isolated and used as donor cells. The in vitro matured oocytes were enucleated and then the isolated donor cells were introduced. One $15{\mu}s$ pulse of 180 volts was applied to induce the fusion between karyoplast and cytoplast. The fused embryos were activated with $10{\mu}M$ calcium ionophore for 5 min and 2 mM 6-dimethylaminopurine for 3 h. To examine the effect of protein supplementation, nuclear transfer (NT) embryos were cultured in one of the following 4 treatments : 1) CR1aa + 3 mg/ml BSA for 7 days ; 2) CR1aa + 10% FBS for 7 days ; 3) CR1aa + 1.5 mg/ml BSA + 5% FBS for 7 days ; and 4) CR1aa + 3 mg/ml BSA for first 3 days and then CR1aa + 1.5 mg/ml BSA + 5% FBS for 4 days. Culture took place at 5% $CO_2$, 5% $O_2$ and 90% $N_2$ at $38.5^{\circ}C$. Although there were no significant differences in cleavage rate among different protein supplements, the rates of blastocyst formation were significantly different. When NT embryos were cultured in the medium supplemented with only BSA, they could develop to only morula not to blastocyst. However, when FBS was supplemented, NT embryos developed to blastocyst stage. In order to investigate the effect of $O_2$ concentration and co-culture, NT embryos were cultured in CR1aa + 1.5 mg/ml BSA + 5% FBS with or without cumulus cell co-culture at an atmosphere of 5% $CO_2$ in air (20% $O_2$) or 5% $CO_2$, 5% $O_2$, 90% $N_2$ (5% $O_2$) at $38.5^{\circ}C$ for 7 days. The percentage of blastocyst development was significantly higher when the NT embryos were cultured at an atmosphere of 5% $O_2$ than that of 20% $O_2$ (p<0.05). However, there was no significant difference between with and without cumulus cell co-culture at an atmosphere of 5% $O_2$ or 20% $O_2$. Fifty embryos were transferred to 25 recipients and 5 recipients were pregnant at 100 days. From 5 pregnant cows, only one cow was delivered of female twin. In conclusion, the embryos reconstructed by enucleation of metaphase II oocytes and introduction of the cycling and quiescent cumulus donor cells in Hanwoo had developmental potential to term after embryo transfer to recipient cows.

Effects of Steroid Hormone in Avian Follicles

  • Caicedo Rivas, R.E.;Nieto, M. Paz-Calderon;Kamiyoshi, M.
    • Asian-Australasian Journal of Animal Sciences
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    • 제29권4호
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    • pp.487-499
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    • 2016
  • The aim of the present study was to examine the effects of testosterone (T) and estradiol-$17{\beta}$ ($E_2$) on the production of progesterone ($P_4$) by granulosa cells, and of the $E_2$ on the production of $P_4$ and T by theca internal cells. In the first experiment, granulosa cells isolated from the largest ($F_1$) and third largest ($F_3$) preovulatory follicle were incubated for 4 h in short-term culture system, $P_4$ production by granulosa cells of both $F_1$ and $F_3$ was increased in a dose-dependent manner by ovine luteinizing hormone (oLH), but not T or $E_2$. In the second experiment, $F_1$ and $F_3$ granulosa cells cultured for 48 h in the developed monolayer culture system were recultured for an additional 48 h with increasing doses of various physiological active substances existing in the ovary, including T and $E_2$. Basal $P_4$ production for 48 h during 48 to 96 h of the cultured was about nine fold greater by $F_1$ granulosa cells than by $F_3$ granulosa cells. In substances examined oLH, chicken vasoactive intestinal polypeptide (cVIP) and T, but not $E_2$, stimulated in a dose-dependent manner $P_4$ production in both $F_1$ and $F_3$ granulosa cells. In addition, when the time course of $P_4$ production by $F_1$ granulosa cells in response to oLH, cVIP, T and $E_2$ was examined for 48 h during 48 to 96 h of culture, although $E_2$ had no effect on $P_4$ production by granulosa cells of $F_1$ during the period from 48 to 96 h of culture, $P_4$ production with oLH was found to be increased at 4 h of the culture, with a maximal 9.14 fold level at 6 h. By contrast, $P_4$ production with cVIP and T increased significantly (p<0.05) from 8 and 12 h of the culture, respectively, with maximal 6.50 fold response at 12 h and 6, 48 fold responses at 36 h. Furthermore, when $F_1$ granulosa cells were precultured with $E_2$ for various times before 4 h culture with oLH at 96 h of culture, the increase in $P_4$ production in response to oLH with a dose-related manner was only found at a pretreatment time of more than 12 h. In the third experiment, theca internal cells of $F_1$, $F_2$ and the largest third to fifth preovulatory follicles ($F_{3-5}$) were incubated for 4 h in short-term culture system with increasing doses of $E_2$. The production of $P_4$ and T by theca internal cells were increased with the addition of $E_2$ of $10^{-6}M$. These increases were greater in smaller follicles. These results indicate that, in granulosa cells of the hen, T may have a direct stimulatory action in the long term on $P_4$ production, and on $E_2$ in long-term action which may enhance the sensitivity to LH for $P_4$ production, and thus, in theca internal cells, $E_2$ in short term action may stimulate the production of $P_4$ and T.