• KCI Concrete Journal
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• 제14권1호
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• pp.51-60
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• 2002

Strengthening of existing concrete structures is a major concern in recent years as the number of degraded structures increases. The purpose of this paper is to investigate the static and fatigue behavior of reinforced concrete (RC) beams strengthened with steel plates. To this end, a comprehensive test program has been set up and many series of strengthened beams have been tested. The major test variables include the plate thickness, adhesive thickness, and the shear-span to depth ratio. The test results indicate that the separation of plates is the dominant failure mechanism even for the full-span-length strengthened beams with steel plate. The theoretical ultimate load capacities for strengthened beams based on the full composite action of concrete beam and steel plate are found to be larger than the actual measured load capacities. The strengthened beams exhibit more dominant shear cracking as the shear-span to depth ratio decreases. The ultimate capacity of strengthened beams increases slightly with the increase of adhesive thickness, which may be caused by the late initiation of plate separation in the beams with thicker adhesive. A realistic concept of ductility for plate-strengthened beams is proposed in this study. It is seen that the strengthened beams show relatively low ductility compared with unstrengthened beams. The present study indicates that the strengthened beams exhibit much higher fatigue resistance than the unstrengthened beams. The increase of deflections of strengthened beams according to the number of load cycles is much smaller than that of unstrengthened beams. The present study provides very useful results for the realistic application of plate-strengthening method in reinforced concrete structures.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2003년도 학술발표대회 발표논문초록집
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• pp.18-18
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• 2003

In human, sudden infant death syndrome(SIDS) is synonyms for the sudden, unexpected and unexplained death of an infant. The incidence of SIDS has been estimated to be from 1 to 3%. Cloning has a relatively high rate of late abortion and early postnatal death, particularly when somatic cells are used as donors of nuclei and rates as high as 40 to 70% have been reported. However, the mechanisms for SIDS in cloned animals are not known yet. To date, few reports provide detailed information regarding phenotypic abnormality of cloned pigs. In this study, most of the cloned piglets were alive at term and readily recovered respiration. However, approximately 82% of male cloned piglets (81/22) died within a week after birth. Significant findings from histological examinations showed that 42% of somatic cloned male piglets died earlier than somatic cloned female piglets, most probably due to severe congestion of lung and liver or neutrophilic inflammation in brain, which indicates that unexpected phenotypes can appear as a result of somatic cell cloning. No anatomical defects in cloned female piglets were detected, but three of the piglets had died by diarrhea due to bacterial infection within 15 days after birth. Although most of male cloned piglets can be born normal in terms of gross anatomy, they develop phenotypic anomalies that include leydig cell hypoplasia and growth retardation post-delivery under adverse fetal environment and depigmentation of hair- and skin-color form puberty onset. This may provide a mechanism for development of multiple organ system failure in some cloned piglets. Th birth weights of male cloned pig in comparison with those of female cloned piglets are significantly reduced(0.8 vs 1.4kg) and showed longer gestational day(120 vs 114). In conclusion, brain meningitis and hepatopneumonic congestion are a major risk factor for SIDS and such pregnancy in cloned animals requires close and intensive antenatal monitoring.

• Asian Pacific Journal of Cancer Prevention
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• 제15권6호
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• pp.2651-2654
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• 2014

Background: Lung cancer (LC) is still the primary cause of cancer deaths worldwide, and late diagnosis is a major obstacle to improving lung cancer outcomes. Recently, elevated preoperative or pretreatment neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR) and mean platelet volume (MPV) detected in peripheral blood were identified as independent prognostic factors associated with poor survival with various cancers, including colon cancer, esophageal cancer, gastric cancer and breast cancer. Objective: The aim of this study was to examine whether MPV, NLR and PLR could be useful inflammatory markers to differentiate lung cancer patients from healthy controls. An investigation was also made of the relationship between these markers and other prognostic factors and histopathological subgroups. Materials and Methods: Retrospectively eighty-one lung cancer patients and 81 age-sexes matched healthy subjects included into the study. Patients with hypertension, hematological and renal disease, heart failure, chronic infection, hepatic disorder and other cancer were excluded from the study. The preoperative or pretreatment blood count data was obtained from the recorded computerized database. Results: NLR and PLR values were significantly higher in the LC patients compared to the healthy subjects.( NLR: 4.42 vs 2.45 p=0.001, PLR: 245.1 vs 148.2 p=0.002) MPV values were similar in both groups (7.7 vs 7.8). No statistically significant relationship was determined between these markers (MPV, NLR and PLR) and histopathological subgroups and TNM stages. Conclusions: NLR and PLR can be useful biomarkers in LC patients before treatment. Larger prospective studies are required to confirm these findings.

• Journal of Chest Surgery
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• 제28권6호
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• pp.565-570
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• 1995

Seventy-three patients with isolated total anomalous pulmonary venous connection the patients associated with other major cardiac anomalies such as single ventricle, DORV[Double Outlet Right Ventricle and large VSD[Ventricular Septal Defect were excluded were underwent surgical repair from January 1980 through October 1993. There were 45 boys and 28 girls. The mean age at operation was 19.9 months[range 6 days to 24 years and mean body weight was 7.1kg[range 2.6kg to 45kg . The anomalous locations of connection were supracardiac in 38, cardiac in 21, infracardiac in 5, and mixed in 9. In 38 patients[52% , the venous drainage was obstructed. The obstruction ratios according to the connection type were as follows: 53%[28/38 in supracardiac, 52%[11/21 in cardiac, 100%[5/5 in infracardiac, 22%[2/9 in mixed type. The associated cardiac anomalies were persistent left SVC[2 , tricuspid valve regurgitation[3 , cor triatriatum[1 , and mitral cleft[1 . And associated noncardiac anomalies were imperforate anus[1 and Neil Weightman syndrome[1 . The operative mortality was 23%. The causes of death were pulmonary hypertensive crisis, perioperative myocardial failure, pneumonia with sepsis, arrhythmia and etc. The statistically significant factors in postoperative mortality were the pulmonary venous obstruction and age [p<0.01 . The operative mortality was high in groups of age under 1 month and pulmonary venous obstruction. The mean follow-up was 27.1 months. There were two late deaths. The first patient was three months old boy with supracardiac type and severe obstructive symptoms. The postoperative echocardiography was showed anastomotic stenosis and reoperations were performed twice but the patients expired due to pneumonia and sepsis. The second patient was three month old boy with supracardiac type and total correction was done and was doing well postoperatively. Eight years later, he expired suddenly due to arrhythmia. But all the other patients were in NYHA Fc I and received no medications. The 5-year survival rate excluding early expired patients is 97.1 $\pm$ 0.03 %. In conclusion, although the operative mortality of total anomalous pulmonary venous connection was relatively high compared to other major cardiac anomalies, we could expect excellent long-term results by early surgical correction.

• Journal of Chest Surgery
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• 제29권3호
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• pp.297-302
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• 1996

1989년 1월부터 1995년 7월까지 상행대동맥 박리환자 18례에 대한 교정수술을 시 행하였다. 남여비는 9 : 9였으며 연령분포는 41세부터 68세까지로 53.8세 였다. 급성박리가 13례, 만성박리가 5례 였다. 수술방법은 급성 13례에서 상행대동맥만 치환한 경우가 6례, 상행대동맥과 대동맥궁 일부를 치환 한 례가 3례, 상행대동맥과 대동맥궁 전부를 치환한 례가 1례, Bentall 술식이 1례, Bentall 술식 에 대동맥 궁 전부를 치환한 례가 1례 있었다. 만성 5례중 Bentall 술식을 시행한 경우가 3례, 상행대동맥을 치환한 경우가 1례, 상행대동맥 에 대동맥궁 일부를 치환한 례가 1례 있었다. 대동맥궁 교정수술을 시행한 환자 7례중 4례에서 선택적 뇌관류법을 시행하였고 3례에서 완전 순환차단법을 시행하였다. 18례중 급성에 서만 4례 사망하여 수술사망율은 22.2%였다. 사망원인은 출혈이 2례, 좌심실부전이 2례였다. 생존환자 14례를 술후 평균 17개월 외래추적하였으며 이중 1례에서 재수술후 2개월째 패혈증으로 사망하였고 나머지 환자는 양호한 편이다.

• Journal of Chest Surgery
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• 제45권1호
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• pp.30-34
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• 2012

Background: The long-term results of homografts used in systemic circulation are controversial. We assessed the long-term results of using a cryopreserved homograft for an aortic root or aorta and its branch replacement. Materials and Methods: From June 1995 to January 2010, 23 patients (male:female=15:8, $45.4{\pm}15.6$ years) underwent a homograft replacement in the aortic position. The surgical techniques used were aortic root replacement in 15 patients and aortic graft interposition in 8 patients. Indications for the use of a homograft were systemic vasculitis (n=15) and complicated infection (n=8). The duration of clinical follow-up was $65{\pm}58$ months. Results: Early mortality occurred in 2 patients (8.7%). Perioperative complications included atrial arrhythmia (n=3), acute renal failure (n=3), and low cardiac output syndrome (n=2). Late mortality occurred in 6 patients (26.1%). The overall survival rates at 5 and 10 years were 66.3% and 59.6%, respectively. Six patients (28.6%) suffered from homograft-related complications. Conclusion: Early results of homograft replacement in aortic position were favorable. However, close long-term follow-up is required due to the high rate of homograft-related events.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.4163-4167
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• 2012

Aims: To prospectively assess the efficacy and safety of moderately hypofractionated conformal radiotherapy in patients with thoracic esophageal cancer. Methods and Materials: From Sept. 2002 to Oct, 2005, 150 eligible patients with T2-4N0-1M0 stage thoracic esophageal squamous cell cancers were enrolled to receive either conventional fractionated radiation (CFR) or moderately hypofractionated radiation (MHR) with a three-dimensional conformal radiation technique. Of the total, 74 received moderately hypofractionated radiation with total dose of 54-60Gy/18-20fractions for 3.5-4 weeks in the MHR arm, and 76 received conventional radiation with total dose of 60Gy/30 fractions for 6 weeks in the CFR arm. Concurrent chemotherapy comprised of paclitaxel and cisplatin. Safety was evaluated, and local control and overall survival rates were calculated. Results: Statistically significant differences between the CFR versus MHR arms were observed in local/regional failure rate (47.3% v 27.0%, P=0.034) and the percentage of patients with persistent local disease (26.3% v 10.8%, P=0.012). But 3 and 5-year overall survival rates (43.2%, 38.8% v 38.2%, 28.0%, respectively) were not different between the two arms (P=0.268). There were no significant differences in the incidences of grade 3 or higher acute toxicities (66.3% v 50.0%) and late complications rates (27.0% v 22.4%) between the MHR and CFR arms. Conclusions: Moderately hypofractionated, three-dimensional radiation treatment could improve the local control rate of esophageal cancer and potentially increase patients' survival.

• Journal of Chest Surgery
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• 제25권11호
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• pp.1327-1336
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• 1992

Between Jan. 1986 and Aug. 1992. 72 patients underwent Rastelli procedure. There were 43 male and 29 female, aged 46 days to 16 years [mean age, 5.2 years] with 18 patients less than 2 years of age. All patients had complex defect, 27 pulmonary atresia with ventricular septal defect, 18 corrected transposition of great arteries with pulmonary atresia or punmonary stenosis, 10 truncus arteriosus, 10 double outlet right ventricle with pulmonary atresia or stenosis, 7 complete transposition of great artersia with pulmonary atresia or pulmonary stenosis. The types of extracardiac valved conduit used were prosthetic valve[n=47, 24 car-bomedics, 19 Ionescu-Shiley, 4 Bjork-shiley] and hand-made trileaflet valve using pericardium. [n=23, 20 bovine pericardium, Z autologous pericardium, 1 equine pericardium] The mean size of valved cinduit was 5.25mm larger in diameter than the size of main pulmonary artery. [normalized to the patient`s body surface area] There were 17 hospital death[24%] and 4 late deaths[5.6%]. Postoperative complication rate was 38.9%a, none of which was conduit-related. All patients were followed pos-toperatively for 1 to 73 months. [mean 25.8 months] During follow-up period, reoperation was done in 6 patients due to stenosis of valved conduit. Mean interval between intial repair and reoperation was 20.3 months. In our experience, li recently extracardaic valved conduits between right ventricle [or pulmonary ventricle] and pulmonary artery were inserted with increasing frequency in infants less than 2 year, but hospital mortality was decreased, 2] Risk of reoperation due to conduit stenosis is low, so that the effect of graft failure on overall survival is minimized. 3] Nevertheless, because any type of extracardaic valved conduit is not ideal in children, we recommended that Lecompte should be done if cardiac anatomy is permitted.

• Journal of Chest Surgery
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• 제22권1호
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• pp.42-49
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• 1989

A total of 420 pyrolytic carbon mechanical valves were implanted in 336 patients from January, 1984, through Jung, 1988. Of the valves implanted, 131 were Bjork-Shiley, 250 St-Jude, and 39 Duromedics. The cumulative follow-up was 398 patient-years with a mean follow-up of 14.4 months per patients. Among 336 patients, 175 had mitral, 68 aortic, 82 multiple, 10 tricuspid, and one pulmonary valve replacement. The hospital mortality figures were 9 of 336[2.67%] in all, 5 of 175[2.85%] in isolated mitral, 1 of 68[1.47%] in isolated aortic and 3 of 82[3.65%] in multiple valve replacement. The causes of hospital mortality were myocardial failure in 5, sepsis in 2, bleeding in 1, cerebral embolism in l. There was no late valve related mortality. The actuarial survival rate at 4.5years was 99.4*0.1%. The complications occurred in 15 of 336[4.46%]; 7 of 175[4.0%] in isolated mitral, 4 of 68[5.88%] in isolated aortic, and 4 of 82[4.89%] in multiple valve replacement. The causes of complications were thromboembolism in 4, hemorrhage in 4, paravalvular leakage in 4, hepatitis in 2, and complete AV block in l. Actuarial probability of survival at 4.5 years was 95.0*0.1%. The low mortality and complications encourage us to applicate these valves to any patient including children and young women.

• Journal of Chest Surgery
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• 제45권3호
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• pp.148-154
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• 2012

Background: The adequate management of mild to moderate dilatation of the ascending aorta during cardiac operations remains controversial. In this study, we present the short-term outcomes of 90 patients undergoing ascending aortic wrapping with a Dacron graft during other cardiac operations. Materials and Methods: From March 2008 to January 2011, 90 consecutive patients underwent treatment for ascending aortic aneurysm using the external wrapping technique during the concomitant procedure. The study group consisted of 49 male and 41 female patients with a mean age of $58.7{\pm}13$years. The primary cardiac surgical procedures were coronary artery bypass grafting (CABG) in 3, aortic valve replacement in 2, and aortic valvuloplasty in 85 patients (isolated in 62 and combined with CABG or mitral valvuloplasty in 23). The ascending aorta diameter was measured using a computed tomography scan within 4 weeks after surgery, and was compared with the preoperative value. Results: The diameters of the ascending aorta wrapped with the Dacron graft were significantly reduced within a month after surgery from $46.4{\pm}4.3$ mm to $33.0{\pm}3.5$ mm (p<0.05). There was no early mortality or major surgical complication. During the mean follow-up period of $15.4{\pm}5.2$ months, there was only one late death caused by septic multiorgan failure. Conclusion: Dacron wrapping of the ascending aorta offers excellent results with very low mortality and morbidity, and it can be regarded as a safe and effective method for the treatment of moderately dilated ascending aorta in selected patients.