• Composites Research
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• v.19 no.5
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• pp.1-6
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• 2006

In this study, a closed-form analysis has been developed for the transverse shear behavior of thin-walled composite beams with closed cross-sections. The shear flow distributions and cross-section stiffness coefficients are derived analytically by using a mixed beam approach. The theory has been applied to single-celled composite box-beams with elastic couplings. The location of the shear center and the effect of transverse shear deformation on the static behavior of composite beams are investigated in the framework of the analysis. The present results are validated against those of a two-dimensional finite element analysis and a good correlation has been obtained for box-beam cases considered in this study.

• Neonatal Medicine
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• v.18 no.2
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• pp.228-233
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• 2011

Purpose: The aim of our study was to compare the efficacy and safety of ibuprofen and indomethacin in the prophylaxis of patent ductus arteriosus (PDA) in preterm infants and to determine whether ibuprofen could be an alternative agent in prophylactic use. Methods: A retrospective study including 37 preterm infants <1,500 g of birth weight, <34 weeks of gestation, whom were administrated indomethacin (n=17; January 2009-December 2009) or ibuprofen (n=20; January 2010-February 2011) within 24 hr after birth was conducted. The rate of ductal closure, need for surgical ligation, clinical outcomes such as necrotizing enterocolitis, intraventricular hemorrhage, bronchopulmonary dysplasia, retinopathy of prematurity (ROP) and death rate were compared. Results: There were no statistically significant differences between the two groups in mean gestational age, mean birth weight, Apgar score, sex, type of delivery, maternal dexamethasone treatment, frequency and duration of ventilator and surfactant treatment. The closure of PDA on day 7 of life was in 19 of 20 infants of the ibuprofen group and 13 of 17 infants of the indomethacin group (P=0.159). Between the two groups, there were no significant differences with respect to clinical outcomes. Conclusion: Ibuprofen has similar effects to indomethacin in the rate of PDA closure. Our study demonstrates that prophylactic ibuprofen is relatively effective without significant differences with respect to clinical outcomes compared with indomethacin. Therefore, ibuprofen may be used as an alternative agent in the prophylaxis of PDA in preterm infants.

• Restorative Dentistry and Endodontics
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• v.19 no.2
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• pp.429-446
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• 1994

The purpose of this study was to evaluate the sealing effect of warm lateral condensation technique by Endotec spreader, comparing with other canal filling techniques. One hundred and forty extracted human teeth with single canal were instrumented and randomly divided into four groups according to canal filling techniques including lateral condensation with sealer, warm lateral condensation with sealer, warm lateral condensation without sealer, and injection-molded thermoplasticized gutta-percha without sealer. Obturated canals were exposed to 2 % methylene blue solution at $37^{\circ}C$ for 24 hours and measurement of the degree of microleakage was done linearly and volumetrically with stereozoom microscope and UV-spectrophotometer respectively. The results were as follows ; When sealer was used, the canals obturated by warm lateral condensation showed less leakage linearly and volumetrically than the canals obturated by standard lateral condensation with no statistically significant difference. The obturated canals by warm lateral condensation with sealer showed less leakage linearly and volumetrically than the canals obturated by warm lateral condensation without sealer and by injection-molded thermoplasticized gutta-percha without sealer with statistical significance (p<0.05). No statistical difference revealed that the group filled with the use of the Endotec had significantly less leakage than any of the other groups. There was a significant correlation between the linear measurement and volumetric measurement(r=0.4459, p<0.05).

• Restorative Dentistry and Endodontics
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• v.15 no.2
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• pp.46-57
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• 1990

The purpose of this study was to spectrophotometrically investigate the sealing effect of the ultrasonic canal obturation with softened gutta-percha utilizing an endosonic plugger by means of ultrasonic vibrations and heat. The 120 extracted human central and lateral incisors with single root were randomly selected, and the root canals were instrumented up to size #60 file by conventional method. The prepared canals were obtruated with gutta-percha by lateral condensation method, McSpadden technique and ultrasonic condensation method, with or without sealer. All specimens were immersed in 2% methylene blue in an incubator at $37^{\circ}C$ for 10 days. The teeth were then dissolved in 5ml of 60% nitric acid solution and the dye present within the root canal system was returned to solution. The leakage of dye was quantitatively measured via spectrophotometric method. The obtained data statistically evaluated usint two-way ANOVA and Student's t-test. The results were as follows : No statistically significant difference in leakage was observed between the lateral condensation method and ultrasonic condensation method, with and without sealer. When sealer was used or not, McSpadden technique showed significantly greater leakage than lateral or ultrasonic condensation method. Statistical analysis of the data indicated that the canals obturated in conjunction with sealer demonstrated less dye leakage than the canals obturated without sealer(p<0.01), except McSpadden technique. The ultrasonic condensation method appeared comparable sealing ability to the lateral condensation method.

• Journal of Yeungnam Medical Science
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• v.14 no.1
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• pp.94-100
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• 1997

To evaluate the efficacy and safety of clarithromycin in acute exacerbation of chronic obstructive pulmonary disease, we administered clarithromycin(250mg) twice in a day in 30 patients with acute exacerbation of chronic obstructive pulmonary disease from September to November in 1996. Twenty eight cases of 30 patients were cured(93.4%) and 2 cases(6.7%) show clincal improvement. Three cases were improved within 3 days of treatment and 24 cases were improved between 5 days and 12 days of treatment. There were no significant side effects. These results suggest that clarithromycin will be effective as a first line therapy in patients with acute exacerbation of chronic obstructive pulmonary disease.

• Journal of Korean Society of Steel Construction
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• v.13 no.5
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• pp.557-566
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• 2001

Composite slab with deckplate needs sufficient bond strength between deckplate and concrete to conduct composite behavior Composite slab can transfer the shear by either chemical adhesion interface interlock, or active friction. There are several way of mechanical shear connection in composite slab. that is embossments shear connector shape of deckplate etc. Effect of mechanical interaction is deped on shape of deckplate which is to prevent peeling between deckplate and concrete and an amount of shear connector. The behavior and strength of the connection between the decking and the concrete slab due to embossments and end anchorage may be estimated using the push-off tests described in this paper We proposed the equation of shear bond strength in the composite slab It will be use to design by basic data in composite slab.

• Journal of Chest Surgery
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• v.34 no.4
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• pp.322-328
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• 2001

배경: 우심실 유출로 재건술후에는 폐동맥판막부전이 우심실기능에 나쁜 영향을 미친다. 이를 막기 위해 여러 재료로 판막을 제조하여 사용하는데 가피 형성이 적은 막형 ePTEE(expanded polytetrafluoroethylene, Goretex) 단엽판막의 효과를 알아보고자 연구를 시행하였다. 대상 및 방법; 1996년 3월부터 1997년 2월까지 우심실유출로 재건술을 시행받고 수술 1일까지 우심실 압력을 측정할 수 있었던 47명중 막형 Goretex단엽판막을 사용한 환자(비교군) 19명, 사용하지 않은 환자(대조군) 28명에서 단엽판막의 유용성을 조사하였다. 두 군간에는 나이, 체중 그리고 McGoon ratio 등에는 통계학적 차이가 없었다.(p>0.05) 이전의 수술은 대조군에서 19번, 비교군에서 22번을 시행하였다. 우심실 유출로에 대한 수술은 대조군에서 REV수술 2예, 우심실폐동맥 연결수술 8예, 우심실 유출로 재개건술 2예, 우심실 유출로에 대한 수술은 대조군에서 16예였으며, 비교군에서는 REV 수술 5예, Rastelli 씨 수술 6예, 재우심실 유출로 재건술 5예, 그리고 우심실 재건술 3예였다. 결과: 대동맥 차단 시간이나 총심폐순환시간에는 두군간의 차이는 없었다. 또한 수술직후와 수술후 1일째 측정한 우심실 압력 및 좌심방압력의 차이도 두군간에는 차이가 없었으며 수술후 7일째 시행한 심에코도 결과 ejection fraction., 우심실/ 좌심실 압력비 , 그리고 우심실 유출로의 압력차, 강심제 투여일수, 호흡기 사용 기간 등에서도 두군간의 차이는 없었으나 흉관 삽입기간이 비교군에서 의미있게 짧았다. 추적 조사 기간 중 비교군 1예에서 사망을 하였으나. Goretex 단엽판막에 의한 것은 아니였으며 심초음파검사상 우심실 유출로 압력차이나 재수술은 두군간에 차이는 없었으나 폐동맥 폐쇄부전은 비교군에서 의미 있게 낮은 것을 보이고 있다. 결론; 막형 Goretex 단엽판막의 조기성적은 우수하였으며 폐동맥 폐쇄분전의 정도를 적게 하는 효과를 보이나 앞으로 이들이 성장함에 따라 우심실 유출로에 폐쇄를 일으키는지는 계속적인 추적관찰이 요구된다.

• Journal of Convergence for Information Technology
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• v.11 no.11
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• pp.248-255
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• 2021

This study confirmed the effects of improving lung damage of celecoxib using an animal model of chronic obstructive pulmonary disease(COPD). It was induced in models LPS + CSE and performed in vitro and in vivo. MTT assay and real-time PCR were performed in MRC5 cells as in vitro, and mRNA expression, BALF, collagen content, and protein expression were confirmed as in vivo. Celecoxib reduced the number of inflammatory cells, cytokine and soluble protein accumulation in BALF, decreased body weight and lung weight in animal models, and improved lung collagen deposition. In addition, the reduction of EMT markers was confirmed through Western blotting and real-time PCR. Consequently, celecoxib is thought to improve lung damage of COPD induced to LPS+CSE by regulating EMT.

• 대한치주과학회:학술대회논문집
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• 1997.11a
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• pp.114-115
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• 1997

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1994.07a
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• pp.81-83
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• 1994