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A study on correlation of teaching efficiency and satisfaction of clinical training in Daegu (임상실습교육의 교수효율성과 임상실습만족도에 관한 상관성 연구 (대구지역을 중심으로))

  • Kim, Jeong-Sook;Jung, Young-Hae
    • Journal of Technologic Dentistry
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    • v.28 no.1
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    • pp.121-142
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    • 2006
  • Collecting materials for study on teaching efficiency and satisfaction of clinical training, it changes. Dental technology's educational procedure to many ways of a prospect. In a circumstance that needed higher level of education, this study is aimed on realizing an importance of clinical training through the various materials that previously carried out and offering basic knowledge to take better clinical training for the students. Study results below 1. This Investigation conducted on 123 of sophomores(70.3%) and 52 of juniors(29.7%) who have been taken clinical training, and men's proportion(51.45%)is a bit higher than girls(48.6%). The 64% of respondents taken largest proportion were 20 to 24 years old. As 67.9% of respondents attended daytime school and 30.3% of them attended nighttime one, their school time shows a little difference. In a question about relation ship, one answered "Harmonious" took largest proportion by 72.6% during training, and about the degree of satisfaction of campus life who answered "normal" were the most with 59.4%. 2. About the reason choosing dental technology as a major, 41.1% taken the most answered "due to the specialized job", "Getting job easily" was second with 26.9%, and third was "recommended from around" with 18.3%. 50.3% of the respondents answered "normal" about the Satisfaction of their major, student marked in grade "B" most with 51.4% 3. In a investigation result about clinical training statues and preference, most(72.6%) choose place less than 10 for clinical training, and 60.6% of them resided own home. About their commuting time from home to training place, 44% was under 30min, 40% took time 30-60min. It shows students prefer shotter distance in terms of choosing training place. 4. Each part manager took large proportion as a clinical trainer with 33.7%, Training curriculum reform and developing method were most answer as a improvement measure after completing training with 30%. 5. The average of total score about clinical training was 3.15 of 5. In the detailed question, 'satisfaction of clinical training' got 3.38 as a highest score, the lowest score was 2.86 that is about satisfaction of clinical training period. The average score about efficiency of study was 2.86 and in detailed question, 'a Role model' got 3.26 as a highest score and participation of student got 3.05 as a lowest score. 6. The result of T-test to see the difference of the satisfaction according to the general character and clinic training condition between teaching efficiency is that the degree of satisfaction of clinical training showed statistical significance only in the degree of satisfaction of campus life(p<0.05), and teaching efficiency has a statistical significance with their age, grade, and satisfaction of campus life (p<0.05). 7. The relation between of teaching efficiency of clinical training and satisfaction of clinical training of dental technologic student has a statistical meaning in significance leveler 0.01. Now, therefore we suggest following based on these result. 1. To elevate satisfaction of clinical training, it agentry needs development of consistent clinical training curriculum. 2. To grasp the satisfaction and requirement, in needs to measure anxiousness and satisfactory degree after completing training 3. To train efficiently and evaluate efficiency over the teaching activities, it needs to develop measuring tools for teaching efficiency in terms of teacher's important rules in a clinical training. 4. Strengthen the relations with the study developing and managing curriculum gathering theoretical knowledge and practice. And make an effort to apply to their students. 5. Let the trainee take a class setting a belief, sense of value, function and obtain behavior by making the students comfort over clinical training as increasing teaching efficiency.

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Impact of IODM and ENSO on the East Asian Monsoon: Simulations through NCAR Community Atmospheric Model (동아시아 몬순 지역에서 IODM과 ENSO의 영향 : NCAR Community Atmospheric Model을 이용한 모의 실험)

  • Oh J.-H.;Chaudhari H. S.;Kripalani R. H.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.7 no.4
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    • pp.240-249
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    • 2005
  • The normal Indian Ocean is characterized by warmer waters over the eastern region and cooler waters over the western region. Changes in sea surface temperature (SST) over the western and eastern Indian Ocean give birth to a phenomenon now referred to as the Indian Ocean Dipole Mode (IODM). The positive phase of this mode is characterized by positive SST anomalies over the western Indian Ocean and negative anomalies over the southeastern Indian Ocean, while the negative phase is characterized by a reversed SST anomaly pattern. On the other hand, the normal Pacific Ocean has warm (cool) waters over the western (eastern) parts. Positive (negative) SST anomalies over the central/eastern (western) Pacific Ocean characterize the E1 Nino phenomenon. The reverse situation leads to the La Nina phenomenon. The coupled ocean-atmosphere phenomenon over the Pacific is referred to as the E1 Nino Southern Oscillation (ENSO) phenomenon. In this study the impact of IODM and ENSO on the East Asian monsoon variability has been studied using observational data and using the Community Atmospheric Model (CAM) of the National Center for Atmospheric Research (NCAR). Five sets of model experiments were performed with anomalous SST patterns associated with IODM/ENSO superimposed on the climatological SSTs. The empirical and dynamic approaches reveal that it takes about 3-4 seasons fur the peak IODM mode to influence the summer monsoon activity over East Asia. On the other hand, the impact of ENSO on the East Asian monsoon could occur simultaneously. Further, the negative (positive) phase of IODM and E1 Nino (La Nina) over the Pacific enhances (suppresses) monsoon activity over the Korea-Japan Sector. Alternatively, IODM appears to have no significant impact on monsoon variability over China. However, El Nino (La Nina) suppresses (enhances) monsoon activity over China. While the IODM appears to influence the North Pacific subtropical high, ENSO appears to influence the Aleutian low over the northwest Pacific. Thus, the moisture supply towards East Asia from the Pacific is determined by the strengthening/weakening of the subtropical high and the Aleutian low.

Saseol-sijo singing aspect of current Gagok (현행 가곡의 사설시조 가창 양상)

  • Kim, Young-Woon
    • Sijohaknonchong
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    • v.43
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    • pp.5-39
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    • 2015
  • Shijo (Korean poetic form) is a representative literature genre of a short poem among the literary works of Korea in the late Chosen Dynasty. The format of Sijo is Normal-Shijo in the form of 3 verses, 6 sections and 12 sound, and the lyrics of one Normal-Shijo has within or without 45 words. But Saseol-sijo, a type of Sijo, there is a work that has more than 100 letters due to the number of lyrics were a lot increased. Among those Saseol-sijo there is a work with 'solemn and elegant feeling' borrowing some verses even from Chinese poem, using a lot of Chinese vocabulary, but there are a lot of works with 'salacious and explicit contents'. Literary work, Shijo, is used for lyrics of vocal music as Gagok (a genre of Korean vocal music for mixed female and male voices) and Sijochang, however, there are many cases that the same Sijo poem is used as lyrics of Gagok and Shijo. But those music that use Saseol-sijo as lyrics among Gagok, the vocal music, are mainly songs with 'solemn feeling' rather than 'salacious work'. This study looked into the reason why the Saseol-sijo with 'salacious and explicit contents' are hard to be used as lyrics in Gagok, confirming the fact that most music singing Saseol-sijo among Gagok that are being handed down till now use lyrics with 'solemn and elegant feeling'. The most important thing among those reasons seems to be irregularly increasing lyrics, and in accordance with accompaniment. Gagok accompanys a number of instruments the fixed melody recorded and delivered in score. So it's almost impossible to play unless it depends on the steadily made song melody and accompaniment melody according to the chosen lyrics in advanced. Also, appreciation of literary works is usually made privately through a private reading activity, but Gagok is conducted through public performance in an open space for many people. Especially, it would have been hard to sing a salacious and explicit song gathered together with men and women of different social status in social system and custom of the late of Chosen Dynasty. This study confirmed the fact that folksy and popular character that was praised for literary characteristic of Saseol-sijo can't be easily found from Saseol-sijo that was called Gagok.

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Anomaly Detection for User Action with Generative Adversarial Networks (적대적 생성 모델을 활용한 사용자 행위 이상 탐지 방법)

  • Choi, Nam woong;Kim, Wooju
    • Journal of Intelligence and Information Systems
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    • v.25 no.3
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    • pp.43-62
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    • 2019
  • At one time, the anomaly detection sector dominated the method of determining whether there was an abnormality based on the statistics derived from specific data. This methodology was possible because the dimension of the data was simple in the past, so the classical statistical method could work effectively. However, as the characteristics of data have changed complexly in the era of big data, it has become more difficult to accurately analyze and predict the data that occurs throughout the industry in the conventional way. Therefore, SVM and Decision Tree based supervised learning algorithms were used. However, there is peculiarity that supervised learning based model can only accurately predict the test data, when the number of classes is equal to the number of normal classes and most of the data generated in the industry has unbalanced data class. Therefore, the predicted results are not always valid when supervised learning model is applied. In order to overcome these drawbacks, many studies now use the unsupervised learning-based model that is not influenced by class distribution, such as autoencoder or generative adversarial networks. In this paper, we propose a method to detect anomalies using generative adversarial networks. AnoGAN, introduced in the study of Thomas et al (2017), is a classification model that performs abnormal detection of medical images. It was composed of a Convolution Neural Net and was used in the field of detection. On the other hand, sequencing data abnormality detection using generative adversarial network is a lack of research papers compared to image data. Of course, in Li et al (2018), a study by Li et al (LSTM), a type of recurrent neural network, has proposed a model to classify the abnormities of numerical sequence data, but it has not been used for categorical sequence data, as well as feature matching method applied by salans et al.(2016). So it suggests that there are a number of studies to be tried on in the ideal classification of sequence data through a generative adversarial Network. In order to learn the sequence data, the structure of the generative adversarial networks is composed of LSTM, and the 2 stacked-LSTM of the generator is composed of 32-dim hidden unit layers and 64-dim hidden unit layers. The LSTM of the discriminator consists of 64-dim hidden unit layer were used. In the process of deriving abnormal scores from existing paper of Anomaly Detection for Sequence data, entropy values of probability of actual data are used in the process of deriving abnormal scores. but in this paper, as mentioned earlier, abnormal scores have been derived by using feature matching techniques. In addition, the process of optimizing latent variables was designed with LSTM to improve model performance. The modified form of generative adversarial model was more accurate in all experiments than the autoencoder in terms of precision and was approximately 7% higher in accuracy. In terms of Robustness, Generative adversarial networks also performed better than autoencoder. Because generative adversarial networks can learn data distribution from real categorical sequence data, Unaffected by a single normal data. But autoencoder is not. Result of Robustness test showed that he accuracy of the autocoder was 92%, the accuracy of the hostile neural network was 96%, and in terms of sensitivity, the autocoder was 40% and the hostile neural network was 51%. In this paper, experiments have also been conducted to show how much performance changes due to differences in the optimization structure of potential variables. As a result, the level of 1% was improved in terms of sensitivity. These results suggest that it presented a new perspective on optimizing latent variable that were relatively insignificant.

Early Results of Heart Transplantaion: A Review of 20 Patients (심장이식술 20례의 조기성적)

  • Park, Chong-Bin;Song, Hyun;Song, Meong-Gun;Kim, Jae-Joong;Lee, Jay-Won;Seo, Dong-Man;Sohn, Kwang-Hyun
    • Journal of Chest Surgery
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    • v.30 no.2
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    • pp.164-171
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    • 1997
  • Heart transplantation is now accepted as a definitive therapeutic modality in patients with terminal hear failure. The first successful heart transplantation in humans was done in 1967 and the first case in Korea was performed in november, 1992. Since the first case in 1992, more than 50 cases have been performed in Korea. A total of 20 patients underwent orthotopic heart transplantation since November, 1992 in Asan Medicla Center. The purpose of this study is to evaluate the early results and the follow-up course of 20 cases of heart transplantation done in Asan Medical Center. The average age of 20 patients was 39.9$\pm$11.8 years old(20~58). The mean follow-up duration was 14.4$\pm$11.2 months(1~41). All patients are alive till now. The blood type was identical in 14 and compatible in 6 patients. ihe original heart disease was dilated cardiomyopathy in 16, valvular heart disease in 2, ischemic cardiomyopathy in 1, and giant cell myocarditis in 1 patient. HLA cross matching for recipient and donor was done in 18 cases and the results were negative for T-cell and B-cell in 16 patients, pos tive for warm B-cell in 2 patients. Among 6 loci of A, B, and DR, one locus was matched in 8 cases, 2 loci in 5 cases, and 3 loci matched in 1 case. The number of acute allograft rejection averaged 2.8$\pm$0.5 (0~6) per case and the number of acute allograft rejection requiring treatment averaged 1.0$\pm$0.9 (1~3) per case. The time interval from operation to the first acute rejection requiring treatment was 35.5$\pm$20.4 days (5~60). Acute humoral rejection was suspected strongly in 1 case and was successfully treated. The left ventricular ejection fraction measured by echocardiography and/or MUGA scan was dramatically increased from 17.5$\pm$6.8 (9~32)% to 58.9$\pm$2.0 (55~62)% after heart transplantation. Temporary pacing was needed in 5 patients over 24 hours but normal sinus rhythm appeared within 7 days in all cases. One patient has been taken permanent pacemaker implantation due to complete AV block appearing 140 days after heart transplantaion. One patient had cyclosporine-associated n urotoxicity during the immediate postoperative period and was recovered after 27 hours. The heart transplantation of Asan Medical Center is on a developing stage but the early result is comparable to that of well established centers in other countries, even though the long-term follow-up result must be reevaluated. We can conclude that the heart transplantion is a promising therapeutic option in patients with terminal heart failure.

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Role of Growth Factors and Cytokines on Bleomycin Induced Pulmonary Fibrosis (Bleomycin 유도 폐 섬유화에 있어서 성장인자 및 Cytokine의 역할)

  • Lee, Yong-Hee;Jung, Soon-Hee;Ahn, Chul-Min;Kim, Sung-Kyu;Cho, Sang-Ho
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.4
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    • pp.871-888
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    • 1997
  • Background : It is now thought that the earliest manifestation of idiopathic pulmonary fibrosis is alveolitis, that is, an accumulation of inflammatory and immune effector cells within alveolar walls and spaces. Inflammatory cells including alveolar macrophages and resident normal pulmonary tissue cells participate through the release of many variable mediators such as inflammatory growth factors and cytokines, which contribute to tissue damage and finally cause chronic pulmonary inflammation and fibrosis. This study was performed to investigate the source and distribution pattern of transforming growth factor-${\beta}_1$(TGF-${\beta}_1$), platelet derived growth factor(PDGF), basic fibroblast growth factor(bFGF), interleukin 1(IL-1), interleukin 6(IL-6), tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and the role of these mediators on bleomycin(BLM)-induced pulmonary injury and fibrosis in rats. Method : Wistar rats were divided into three groups(control group, BLM treated group, BLM and vitamine E treated group). Animals were sacrificed periodically at 1, 2, 3, 4, 5, 7, 14, 21, 28 days after saline or BLM administration. The effects were compared to the results of bronchoalveolar lavage fluid analysis, light microscopic findings, immunohistochemical stains for six different mediators(TGF-${\beta}_1$, PDGF, bFGF, IL-1, IL-6 and TNF-$\alpha$) and mRNA in situ hybridization for TGF-${\beta}_1$. Results : IL-1 and IL-6 are maximally expressed at postbleomycin 1~7th day which are mainly produced by neutrophils and bronchiolar epithelium. It is thought that they induce recruitment of inflammatory cells at the injury site. The expression of IL-1 and IL-6 at the bronchiolar epithelium within 7th day is an indirect evidence of contribution of bronchiolar epithelial cells to promote and maintain the inflammatory and immune responses adjacent to the airways. TNF-$\alpha$ is mainly produced by neutrophils and bronchiolar epithelial cells during 1~5th day, alveolar macrophages during 7~28th day. At the earlier period, TNF-$\alpha$ causes recruitment of inflammatory cells at the injury site and later stimulates pulmonary fibrosis. The main secreting cells of TGF-${\beta}_1$ are alveolar macrophages and bronchiolar epithelium and the target is pulmonary fibroblasts and extracellular matrix. TGF-${\beta}_1$ and PDGF stimulate proliferation of pulmonary fibroblasts and TGF-${\beta}_1$ and bFGF incite the fibroblasts to produce extracellular matrix. The vitamine E and BLM treated group shows few positive cells(p<0.05). Conclusion : After endothelial and epithelial injury, the neutrophils and bronchiolar epithelium secrete IL-1, IL-6, TNF-$\alpha$ which induce infiltration of many neutrophils. It is thought that variable enzymes and $O_2$ radicals released by these neutrophils cause destruction of normal lung architecture and progression of pulmonary fibrosis. At the 7~28th day, TGF-${\beta}_1$, PDGF, bFGF, TNF-$\alpha$ secreted by alveolar macrophages sting pulmonary fibroblasts into proliferating with increased production of extracellular matrix and finally, they make progression of pulmonary fibrosis. TNF-$\alpha$ compares quite important with TGF-${\beta}_1$ to cause pulmonary fibrosis. Vitamine E seems to decrease the extent of BLM induced pulmonary fibrosis.

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Clinical Manifestations of the Lung Involvement in Behçet's Syndrome (Behçet 증후군에서 폐침범의 임상양상에 관한 고찰)

  • Park, Kwang Joo;Park, Seung Ho;Kim, Sang Jin;Kim, Hyung Jung;Chang, Joon;Ahn, Chul Min;Kim, Sung Kyu;Lee, Won Young
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.5
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    • pp.763-773
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    • 1996
  • Background : Behçet's syndrome is a chronic multisystemic disease affecting many organs such as skin, mucosa, eye, joint, central nervous system and blood vessels. Lung involvement occurs in 5% of Behçet's syndrome and is thought to be due to the pulmonary vasculitis leading to thromboembolism, aneurysm and arteriobronchial fistula. Pulmonary vasculitis in Behçet's syndrome is a unique clinical feature, differing from other vasculitis affecting the lung and is one of the major causes of death. Therefore, we examined the incidence, the clinical features, the radioloic findings and the clinical courses of the lung involvement in Behçet's syndrome. Methods: We retrospectively reviewed the medical records and radiologic studies of 10 cases of the lung involvement in Behçet's syndrome diagnosed at Yongdong Severance Hospital and Severance Hospital from 1986 to 1995. We analysed the clinical features, the radiological findings, the treatment modalities and the clinical courses. Results: 1) The incidence of the lung involvement in Behçet's syndrome was 2%(10/487). The male to female ratio was 8 : 2 and the mean age was 34 years. The presenting symptom was hemoptysis in 5 of 10 cases, and massive hemoptysis was noted in 2 cases. Other pulmonary symptoms were cough(6/10), dyspnea(4/10), and chest pain(2/10). Other manifestations were oral ulcers(10/10), genital ulcers(9/10), skin lesions(7/10), and eye lesions(6/10). 2) The laboratory findings were nonspecific. The posteroanterior views of chest radiographies showed multiple infiltrates(6/10), nodular or mass-like opacities(4/10), or normal findings(2/10). The chest CT scans showed multifocal consolidations(6/8), and aneurysms of the pulmonary aneries(4/8). The pulmonary angiographies were performed in 3 cases, and showed pulmonary artery aneurysms in 2 cases. The ventilation-perfusion scans in 2 cases of normal chest x-ray showed multiple mismatched findings. 3) The patients were treated with combination therapy consisting of corticosteroids, cyclophosphamide, and colchicine or anticoagulant agents. Surgical resection was performed in one case with a huge aneurysm. 4) We have followed up nine of ten cases. Three cases are well-being with medical therapy, two cases are severely disabled now and four cases died due to massive hemoptysis, massive pulmonary embolism, or sepsis. Conclusion : Pulmonary vasculitis is a main feature of the lung involvement of Behçet's syndrome, causing hemorrhage, aneurysmal formation, and/or thromboemboism. The lung involvement of Behçet's syndrome is uncommon but is one of the most serious prognostic factors of the disease. Therefore, an aggressive diagnostic work-up for early detection and proper treatment are recommended to improve the clinical course and the survival.

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Reoperations after Fontan Procedures (폰탄 술식 후에 시행한 재수술)

  • Lee, Cheul;Kim, Yong-Jin;Lee, Jeong-Ryul;Rho, Joon-Ryang
    • Journal of Chest Surgery
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    • v.36 no.7
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    • pp.457-462
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    • 2003
  • Background: Surgical results of the Fontan procedures in patients with a single ventricle have improved. As the perioperative mortality continues to decline and late outcome is forthcoming, attention is now being directed toward late complications of the Fontan procedures. We retrospectively analyzed our experience with reoperations after Fontan procedures. Material and Method: Between January 1988 and December 2002, 24 patients underwent reoperations after Fontan procedures. The median age at Fontan procedures and reoperation was 3.3 years and 9.2 years, respectively. Types of initial Fontan procedures were atriopulmonary connection (n=11), lateral tunnel Fontan (n=11), and extracardiac conduit Fontan (n=2). Indications for reoperation included atrioventricular valve regurgitation (n=7), atrial arrhythmia (n=8), Fontan pathway stenosis (n=7), residual right-to-left shunt (n=5), etc. Result: Procedures performed at reoperation included atrioventricular valve replacement (n=6), conversion to lateral tunnel Fontan (n=5), conversion to extracardiac conduit Fontan (n=3), cryoablation of arrhythmia circuit (n=7), etc. There was no operative mortality. There were 2 late deaths. Mean follow-up duration was 2.7$\pm$2.1 years. All patients except two were in NYHA class I at the latest follow-up. Among 8 patients with preoperative atrial arrhythmia, postoperative conversion to normal sinus rhythm was achieved in 7 patients. Conclusion: Reoperations after Fontan procedures could be achieved with low mortality and morbidity. Reoperation may lead to clinical improvement in patients with specific target conditions such as atrioventricular valve regurgitation, refractory atrial arrhythmia, or Fontan pathway stenosis, especially in patients with previous atriopulmonary connection.

Tre Effect of UW Solution for Protection of Ischemic Injury in Free Myocutaneous Flaps of the Rabbit (가토 근피판에서 허혈성 손상 방지를 위한 UW 관류제 사용의 효과)

  • Suh Woo-Suk;Kwun Woo-Heung;Kim Sang-Woon;Lee Su-Jung;Kwun Koing-Bo
    • Korean Journal of Head & Neck Oncology
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    • v.9 no.1
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    • pp.3-9
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    • 1993
  • The benficial effects for perfusion in the preservation of free flaps have been controversial in the clinical and experimental field until now. This study was undertaken to observe the effect of UW solution. a recently developed. high molecular weight. organ perfusion solution. for protection of ischemic injury in normothermic free myocutaneous flaps. Forty rabbits were used in this sutdy. A 1x2x1cm sized gastrocnemius myocutaneous flap based on the feeding vessel from common femoral artery was made. The author set up the ischemic time for 12 hours in these flaps. The flap was washed out with normal saline(control grop, n=10), urokinase(comparative group I, n=10), UW solution before ischemic time(comparative group II, n=10) and UW solution before ischemic time and pentoxifylline before reperfusion(comparative group III, n=10). Afterthen, reperfusion was made for 12 hours. After this procedure, we checked the degree of ischemia and necrosis of myocutaneous flap by gross finding, electrical stimulation test of muscle, triphenyltetrazolium chloride staining and wet/dry weight ratio. The degree of necrosis of comparative group II and III were lesser than control and urokinase group in gross finding(p<0.05). In the electrical stimulation test of muscle, there was no statistical difference between control($1.76{\pm}1.01$) and urokinase($2.36{\pm}\1.02$) group however the muscular power of comparative group II($3.54{\pm}0.93$) and III($3.49{\pm}1.37gm/mm^2$) demonstrated significantly higher than control group(p<0.05). The ischemic findings were found in seven cases of control group and three cases of urokinase group but there were no ischemic findings in comparative group II and III in TIC stain(p<0.05). In the wet/dry weight ratio of flaps in order to evaluate the tissue edema. there was no statistical difference between control($4.55{\pm}0.29$) and III($3.75{\pm}0.48$) were scored significantly lesser than control and urokinase group (p<0.05). These results suggest that perfusion washout with UW solution improves the viability of normothermic free myocutaneous flap by inhibition of cellular swelling.

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Microbe Hunting: A Curious Case of Cryptococcus

  • Bartlett, Karen H.;Kidd, Sarah;Duncan, Colleen;Chow, Yat;Bach, Paxton;Mak, Sunny;MacDougall, Laura;Fyfe, Murray
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2005.06a
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    • pp.45-72
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    • 2005
  • C. neoformans-associated cryptococcosis is primarily a disease of immunocompromised persons, has a world-wide distribution, and is often spread by pigeons in the urban environment. In contrast, C. gattii causes infection in normal hosts, has only been described in tropical and semi-tropical areas of the world, and has a unique niche in river gum Eucalyptus trees. Cryptococcosis is acquired through inhalation of the yeast propagules from the environment. C. gattii has been identified as the cause of an emerging infectious disease centered on Vancouver Island, British Columbia, Canada. No cases of C. gattii-disease were diagnosed prior to 1999; the current incidence rate is 36 cases per million population. A search was initiated in 2001 to find the ecological niche of this basidiomycetous yeast. C. gaftii was found in the environment in treed areas of Vancouver Island. The highest percentage of colonized-tree clusters were found around central Vancouver Island, with decreasing rates of colonization to the north and south. Climate, soil and vegetation cover of this area, called the Coastal Douglas fir biogeoclimatic zone, is unique to British Columbia and Canada. The concentration of airborne C. gattii was highest in the dry summer months, and lowest during late fall, winter, and early spring, months which have heavy rainfall. The study of the emerging colonization of this organism and subsequent cases of environmentally acquired disease will be informative in planning public health management of new routes of exposure to exotic agents in areas impacted by changing climate and land use patterns. Cryptococcosis is an infection associated with an encapsulated, basidiomycetous yeast Cryptococcus neoformans. The route of entry for this organism is through the lungs, with possible systemic spread via the circulatory system to the brain and meninges. There are four cryptococcal serogroups associated with disease in humans and animals, distinguished by capsular polysaccharide antigens. Cryptococcus neoformans: variety grubii (serotype A), variety neoformans (serotype D), and variety gattii (serotypes B and C) (Franzot et at. 1999). C. neoformans variety gattii has recently been elevated to species status, C. gattii. C. neoformans val. grubii and var. neoformans have a world-wide distribution, and are particularly associated with soil and weathered bird droppings. In contrast, C. gattii (CG) is not associated with bird excrement, is primarily found in tropical and subtropical climates, and has a restricted environmental niche associated with specific tree species. (Ellis & Pfiffer 1990) Ellis and Pfeiffer theorize that, as a basidiomycete, CG requires an association with a tree in order to become pathogenic to mammals. In Australia, CG has been found to be associated with five species of Eucalypts, Eucalyptus camaldulensis, E. tereticornis, E. blakelyi, E. gomphocephala, and E. rudis. Eucalypts, although originally native to Australia, now have a world-wide distribution. CG has been found associated with imported eucalypts in India, California, Brazil, and Egypt. In addition, in Brazil and Columbia, where eucalypts have been naturalized, native trees have been shown to harbour CG (Callejas et al. 1998; Montenegro et al. 2000). In British Columbia, Canada, since the beginning of 1999, there have been 120 confirmed cases of cryptococcal mycoses associated with CG in humans, including 4 fatalities (data from British Columbia Centre for Disease Control), and over 200 cases in animal pets in BC (data from Central Laboratory for Veterinarians). What is remarkable about the BC outbreak of C. gattii-cryptococcosis is that all of the cases have been residents of, or visitors to, a narrow area along the eastern coast of Vancouver Island, BC, from the tip of the island in the south (Victoria) to Courtenay on the north-central island as illustrated in Figure 1. Of the first 38 human cases, 58% were male with a mean age of 59.7 years (range 20 - 82): 36 cases (95%) were Caucasian. Ten cases (26%) presented with meningitis, the remainder presented with respiratory symptoms. Cultures recovered from cases of cryptococcosis associated with the outbreak were typed as serogroup B, which is specific to CG (Bartlett et al. 2003). This was the first reported outbreak of CVG in Canada, or indeed, the world. Where infection with CG is endemic, for example, Australia, the incidence of cryptococcosis ranges from 1.8 - 4.7 per million between the southern and northern states (Sorrell 2001). However, the overall incidence of cryptococcosis in immunocompenent individuals has been estimated at 0.2 per million population per year (Kwon-Chung et al. 1984). The population of Vancouver Island is approximately 720,000,consequently, even if the organism were endemic, one would expect a maximum of 0.15 cases of cryptococcal disease annually.

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