• ALGAE
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• v.18 no.3
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• pp.199-205
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• 2003

It has been considered that genus Cosmarium including Staurastrum had the problems in grouping by morphological characters. Sequence data for the Cytochrome Oxidase subunit III (coxIII) were employed to compare with taxa of two divisions of this genus, with sections in each, for evaluating the taxonomic stability of these morphological characters. The division and section systems were not coincided with the phylogeny inferred from coxIII sequences, as the previous reports from us using nuclear rDNA ITS and chloroplast rbcL sequence comparisons in this genus. Two taxa of Staurastrum were not placed within a same clade each other, and one taxon of these was grouped in Arthrodesmus clade. Two genera, Cosmarium and Staurastrum, cannot be regarded as monophyletic from this result. Mitochondrial coxIII gene was considered as a useful phylogenetic tool to evaluate evolutionary relationships of desmids as in the case of land plants.

• ALGAE
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• v.19 no.3
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• pp.153-160
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• 2004

The intergeneric relationship of Staurastrum complex including genus Arthrodesmus and Xanthidium was studied on the basis of mitochondrial coxⅢ sequence variation. Teiling's suggestion that Staurodesmus was an independent genus apart from genus Staurastrum, Arthrodesmus and Cosmarium was also reevaluated. The phylogeny inferred from coxⅢ gene was not consistent with morphological characteristics of Staurastrum complex. Genus Staurastrum was closely related to genus Xanthidium in the phylogenetic analysis of coxⅢ, but distant to genus Staurodesmus. The taxonomic treatment of genus Staurodesmus as an independent entity could not be determined, because Staurodesmus did not firm a monophyletic Glade. Therefore, genus Staurodesmus could not be treated as an independent genus as Prescott et al. (1982) claimed.

• Journal of Chest Surgery
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• v.32 no.3
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• pp.249-254
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• 1999

Background: Recovery of the left atrial contractile function after the Cox-Maze procedure is related to the size of the left atrium. We have postulated that if too wide area of the atrium were isolated electrically, then the atrial contractile function would be impaired postoperatively. We have modified the Cox-Maze procedure to dissect each pair of the pulmonary veins separately instead of the conventional pulmonary vein encircling incision, and compared the atrial contractile function after each procedure. Material and Method: From February 1995 to October 1997, 55 cases of the Cox-Maze procedure were performed in mitral valvular heart disease. We excluded the cases that did not covert to sinus rhythm. The patient groups were divided according to the interpulmonary vein distance(IPVD) and the procedure performed. Group I was IPVD under 6.5 cm(n=30), group II was IPVD over 6.5cm and the conventional Cox-Maze III procedure was performed(n=16), and group III was IPVD over 6.5cm and the modified Cox-Maze procedure was performed(n=9). Result: Atrial contractile function was evaluated by the echocardiography follow-up between 6 months to 12 months. The right atrial contractile function recovered gradually, the recovery rate after long-term follow-up was 90% in group I, 81% in group II, and 100% in group III(p>0/05). In the left atrium the recovery rate was 63% in group I, 31% in group II(p=0.03), and 66% in group III(p>0.05). Conclusion: The modified Cox-Maze procedure may have beneficial effects on the recovery of the left atrial contractile function, however, there are no statistically significant values. Therefore, further evaluation of this procedure is necessary.

• Journal of Chest Surgery
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• v.31 no.7
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• pp.668-673
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• 1998

During the past several years, the maze operation has become the most effective method of treatment for chronic atrial fibrillation. When the maze procedure is done concomittantly with other cardiac operations, surgeons, in their initial experiences, may be concerned about the additional operative risks and uncertainty of the results. We performed the Cox-maze III procedure in six cases of chronic atrial fibrillation associated with mitral, mitral & aortic, or coronary arterial disease. Maze III procedure was done with open mitral commissurotomy(3 cases), mitral valve replacement(1 case), aortic and mitral valve replacement(1 case), and two-vessel coronary bypass graft(1 case). In spite of rather prolonged aortic cross clamp time, cardiac recovery was uneventful in all cases. No cases required reexploration for postoperative bleeding. All patients showed regular sinus rhythms immediate or between 2 and 20 days postoperateratively. Transient postoperative supraventricular arrhythmarias were easily controlled by various antiarrhythmic agents. In follow up evaluations, all cases showed regular sinus rhythm on ECG and the right and left atrial transport function was confirmed by Doppler echocardiography in all except one. Though our experience was limited in case number, the Cox-maze III procedure was effective in controlling the chronic atrial fibrillation without serious additional operative risks.

• Journal of Chest Surgery
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• v.33 no.11
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• pp.863-868
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• 2000

배경: Cox-Maze III (CM-III) 술식은 복잡한 심방 절개로 인한 긴 수술시간 때문에 다른 개심 수술과 병행하여 시행하기 어려운 단점이 있다. 대상 및 방법: 저자들은 CM-III 술직을 다음과 같이 변형하여 시행하고 그 임상성적을 분석하였다. \circled1 좌심방이를 절제하는 대신 좌심방이를 외부에서 결찰하고, \circled2 폐정맥 분리 절개선과 좌심방이 사이에 냉동절제술을 시행하며, \circled3 우심방이를 절제하는 대신에 우심방 외측 절개선을 우심방이까지 연장하고, \circled4 후종 우심방 절개 하부에서 우심방 외측을 지나 삼첨판막륜으로 향하는 T-자 절개선을 생략하였다. 저자들이 시행한 변형 술식의 용이성과 효율성을 평가하기 위하여, 우리나라에서도 빈도가 높은 류마치스성 승모판막 질환에서, 전통적인 Cox-III 술식(그룹 I)의 임상결과와, 변형된 CM-III 술식(그룹 II)의 임상결과를 비교하였다. 결과: 그룹 I(n=18)에서 동반된 수술은 승모판막 치환술 10례, 승모판막 성형술3례, 승모판막 치환술과 삼첨판막륜 성형술3례, 승모판막 재치환술 2례 등이었다. 그룹II(n=23)에서 동반된 수술은 승모판막 치환술 7례, 승모판막 성형술 5례, 승모판막 치환술과 삼첨판막륜 성형술 1례, 승모판막 재치환술 10례 등이었다. 그룹 I과 그룹 II에서 평균 대동맥 차단 시간(ACC)은 각각 135$\pm$29분과 104$\pm$18 분, 심패바이패스(CPB) 시간은 각각 240$\pm$33분과 185$\pm$42분이었다. 그룹 I과 그룹 II의 평균 추적 관찰 기간은 각각 47$\pm$14 개월과 29$\pm$4 개월이었다. 그룹 I에서는 16례(88.9%)에서 정상 동율동으로 회복되었고 1례에서 심방세동이 남아 있었으며, 다른 1례는 서맥증후군(sick sinus syndrome)으로 인공 심박조율기를 삽입하였다. 그룹 II에서는 21례(91.3%)에서 정상 동율동으로 회복되었고 2례는 심방세동이 지속되었다. 그룹 I에서 정상동율동으로 회복된 16례는 100%(16/16)에서 우심방의 수축을 심장 초음파검사에서 확인할 수 있었으며, 좌심방의 수축은 75%(12/16)에서 확인할 수 있었다. 그룹 II에서는 정상 동율동으로 회복된 21례 중 100%(21/21)에서 우심방의 수축을 확인할 수 있었으며, 좌심방의 수축은 76.2%(16/21)에서 확인할 수 있었다. 결론: 변형 CM-III 술식은 전통 CM-III 술식에 비하여 ACC time(p<0.005)과 CPB time(p<0.001)을 의미있게 줄이면서도 필적할 만 한 정상 동율동 전환율과 심방 수축력의 회복을 보여주었다.

• Journal of the Korean Data and Information Science Society
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• v.28 no.2
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• pp.349-359
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• 2017

In this paper, we conducted survival analyses by fitting the Cox proportional hazards model to stage III proximal colon cancer data obtained from the Surveillance, Epidemiology, and End Results program of the National Cancer Institute. We investigated the effect of covariates on the hazard function for death from proximal colon cancer in stage III with surgery performed and estimated the survival probability for a patient with specific covariates. We showed that the proportional hazards assumption is satisfied for covariates that were used to analyses, using a test based on the Schoenfeld residuals and plots of the Schoenfeld residuals and $log[-log\{{\hat{S}}(t)\}]$. We evaluated the model calibration and discriminatory accuracy by calibration plot and time-dependent area under the ROC curve, which were calculated using 10-fold cross validation.

• Journal of Chest Surgery
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• v.41 no.3
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• pp.313-319
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• 2008

Background: The Cox maze-III procedure is considered as the most effective surgical treatment for atrial fibrillation. Because this procedure takes a long time and it complicates the concomitant cardiac surgery, some surgeons perform a left atrial maze procedure or pulmonary vein isolation only to reduce the operation time. This study was performed to evaluate how the modified procedures, with using cut-and-sew techniques, can influence the treatment of atrial fibrillation. Material and Method: Between Feb 1999 and June 2005, 40 patients (17 males and 23 females) with organic heart disease and atrial fibrillation underwent the Cox maze-III procedure (23), the left atrial maze procedure (10) or pulmonary vein isolation (7). The cut-an-sew technique was used to ablate the atrial wall, but cryoablation was used instead of the cut-and-sew technique for the coronary sinus and the inferior wall between the pulmonary vein and the mitral annulus. Result: After a mean follow-up period of $50.0{\pm}21.6$ months, all (100%) of the 23 patients who underwent the Cox maze-III procedure had regular sinus or atrial rhythm conversion, and 7(70%) of 10 with a left atrial maze procedure and 4(57.1%) of 7 with pulmonary vein isolation had regular sinus or atrial rhythm conversion (p=0.002). Conclusion: To obtain a high conversion rate from atrial fibrillation to a regular sinus rhythm or a regular atrial rhythm, the standard Cox maze-III procedure should be performed in both atria. The limited modified procedures like the left atrial maze procedure or pulmonary vein isolation may reduce the cure rate of atrial fibrillation.

• Journal of Chest Surgery
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• v.31 no.12
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• pp.1230-1233
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• 1998

The Cox-Maze procedure was developed as a cure for atrial fibrillation. The recovery rate of both atrial contractility is reported low in the atrial fibrillation associated with mitral valvular heart disease than that of loan atrial fibrillation. We performed the Cox-Maze procedure (Maze III) in three cases who suffered from non-mitral heart diseases associated with atrial fibrillation: A ruptured sinus of Valsalva aneurysm, a ventricular septal defect, and an aortic stenoinsufficiency. The Cox-Maze procedure was performed concomitantly with correction of the underlying heart disease. Conversion to sinus rhythm was achieved in all three patients, and both right and left atrial mechanical activities could be identified echocardiographically after three postoperative months.

• Journal of Chest Surgery
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• v.37 no.7
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• pp.609-612
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• 2004

Even though the Cox-Maze III procedure is the gold standard in the therapy for atrial fibrillation (AF) and its outcome is excellent, the complexity of the operation, longer cardiopulmonary bypass time and the risk of bleeding have tended to dissuade cardiac surgeons from its application. The recent data of the pathogenesis of AF and the development of alternative energy sources have facilitated the development of the modified Cox-Maze procedure rapidly. We reported that atrial fibrillation was conversed to sinus rhythm by the epicardial microwave ablation without cardiopulmonary bypass and the normal sinus rhythm was observed during 33 months of follow-up period.

• Proceedings of the KTCVS Conference
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• 1998.10a
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• pp.58-58
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• 1998