• Journal of Chest Surgery
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• 제20권4호
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• pp.643-654
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• 1987

The effect of prostacyclin[PGI, ] on myocardial preservation during global ischemia was studied in the isolating working rabbit heart model. Forty hearts underwent a 15 minute period of retrograde nonworking perfusion with Krebs-Henseleit buffer solution [37*C] and were switched over to the working mode for 15 minutes. After baseline measurement of heart rate, peak aortic pressure, aortic flow, and coronary flow, all hearts were subjected to 60 minutes of ischemic arrest at 10*C induced with St. Thomas Hospital cardioplegic solution: Group I had single dose cardioplegia, Croup II double dose, Croup III oxygenated double dose, and Group IV single dose with PCI, infusion [10ng/min./gm heart weight]. Hearts were then revived with 15 minute period of nonworking reperfusion at normothermia, followed by 30 minutes of working perfusion. Repeat measurements of cardiac function were obtained and expressed as a percent of the preischemic baseline values. Oxygen content of arterial perfusate and coronary effluent was measured by designed time interval. Leakage of creatine kinase was determined during post-ischemic reperfusion period. Finally wet hearts were weighed and placed in 120*C oven for 36 hours for measurement of dry weight. In the PGI, treated group [IV], heart rate increased consistently throughout the period of reperfusion from 100*5.0% [p<0.001] to 107*6.2% [p<0.001]. The percent recovery of aortic flow showed 95*5.7% [p<0.001] at the first 3 minute and full recovery through the subsequent time. Coronary flow was augmented significantly in the 3 minute [96*6.2%, p<0.001] and then sustained above baseline values. Among the Croup I, II, and III, all hemodynamic values were significantly below preischemic levels. PGI2 relatively increased oxygen delivery [1.22*0.19ml/min, p<0.001] and myocardial oxygen consumption [0.90*0.13ml/min, p<0.001] during reperfusion period. Leakage of creatine kinase in the PGI2 group was 9.3*1.58IU/15min [p<0.001]. This was significantly lower than Group I [33.0*2.68 IU/15min]. The water content of PCI2 treated hearts [81*0.9%, p<0.001] was also lower than the other groups.

• 한국임상수의학회지
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• 제16권2호
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• pp.381-388
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• 1999

These investigations were performed to determine the causes of the reproductive disorders of the sows in a pig farm which was located at the distance 36m away from the detonation spot. The reproductive problems of the sows such as abortion and infertility occurred after consecutive detonation and use of heavy equipments to build 6 piers of the bridge for the expressway between Jinju and Taeieon during the period from July 1997 to October 1998. 1. The management condition of the farm, microorganism in the feed, inbreeding, hematological conditions, and viral agent causing abortion were not proved as the factors of the occurrence of abortion and infertility in the pig farm. 2. Theoretical concussion values according to the average amount of explosive per detonation were 1.16 kine for minimum amount (3.6 kg) and 3.45 kine for maximum amount(12.5 kg) of explosive, and the theoretical sound values were accordingly 92.29 decibel for minimum amount and 101.76 decibel for maximum amount of explosive, respectively, in the case of 36m distance between the detonation spot and pig farm. The frequency of detonation in a day was 7 times with interval of 15 minutes. 3. The occurence of infertility in the farm was 57.3% during the period of construction from July 1997 to August 1998. 4. In comparison of body weight of piglets between the damaged and not damaged farms, growth of piglets at the damaged farm was shown to be delayed over 30 days than those of not-damaged farm. In conclusion, abortion of 40 sows, delivery of whole still births of 22 sows, and infertility of 122 sows in the pig farm were assumed to be caused by the concussion or sound stress after consecutive detonation and use of heavy equipments.

• Journal of Periodontal and Implant Science
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• 제44권2호
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• pp.85-93
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• 2014

Purpose: Low birth weight (LBW) is one of the major public health problems in India. Hence, there is a need to identify risk factors that, when modified, will reduce the burden of unhealthy children on the healthcare system. The objective of this study was to determine whether periodontitis among mothers in the rural population of India is a risk factor for LBW babies. Methods: A hospital-based case control study was conducted among 340 postpartum mothers. The cases consisted of 170 women who had given birth to babies weighing <2,500 g, while the control group consisted of 170 women who had given birth to babies weighing ${\geq}2,500g$. Details of the mothers were taken from the hospital records and through a personal interview, and a full-mouth periodontal examination was performed postpartum, which included probing depth, clinical attachment level, and bleeding on probing on six sites per tooth. Results: LBW cases had a significantly worse periodontal status than the controls, having an odds ratio (OR) of 2.94 (P=0.01). The multivariate logistic regression model demonstrated that periodontal disease is a significant independent risk factor with an adjusted odds ratio (aOR) of 2.85 for the LBW group (95% confidence interval [CI], 1.62-5.5). Other factors showing significant associations with LBW were pre-eclampsia (aOR, 4.49; 95% CI, 1.4-14.7), preterm labor (aOR, 5.5; 95% CI, 3.2-9.9), and vaginal type of delivery (aOR, 2.74; 95% CI, 1.4-5.2). Conclusions: Periodontitis represents a strong, independent, and clinically significant risk factor for LBW. Periodontal therapy should form a part of the antenatal preventive care among rural women in India.

• 전자공학회논문지CI
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• 제44권3호
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• pp.49-56
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• 2007

IEEE 802.15.4 저속 무선 개인 통신망(low rate wireless personal area network)은 유비쿼터스 센서네트워크를 구성하는데에 적합한 프로토콜이다. 그러므로, 최근에 다양한 응용네트워크에서 IEEE 802.15.4 프로토콜에 대한 관심이 증대하고 있다. 본 논문에서는 실시간 트래픽 처리를 위하여 보장 시간 슬롯(Guaranteed time slots, GTS)을 할당하며, 이러한 할당방식을 적용시에 IEEE 802.15.4 프레임 및 부프레임과 관련된 최적의 파라미터들을 획득하는 방법을 제안한다. 네트워크에 있는 각 노드에 할당된 대역폭과 주기값에 대한 요구사항들이 주어질 때, 이들 요구사항들을 만족시키는 비콘 주기(beacon period)와 활성/비활성 부프레임 시간들의 후보들을 선택하고, 이들 중 가장 낮은 듀티 사이클(duty cycle)을 낼 수 있는 파라미터를 선택한다. 이들 최적 파라미터를 기반으로 하여 본 논문의 분석 결과는 소모전력 절약을 포함한 네트워크 자원을 효율적으로 이용할 수 있는 방식을 제공한다.

• Clinical and Experimental Pediatrics
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• 제63권2호
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• pp.48-51
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• 2020

Background: The etiopathogenesis of late preterm (LPT) birth is undetermined. Placental histopathology, which reflects an adverse intrauterine environment and is reportedly associated with preterm labor and neonatal morbidities, has not been studied in LPT infants. Purpose: We investigated placental pathological lesion as markers of an adverse intrauterine environment during LPT labor. Methods: This retrospective case-control study compared placental histopathological and clinical variables between LPT and term neonates. Placental variables included chorioamnionitis, funisitis, hemorrhage, abruption, infarction, calcification, and syncytial knots. Maternal variables included age, substance abuse, pregnancyassociated diabetes mellitus and hypertension, duration of rupture of membrane, antibiotic use, and magnesium sulfate, whereas, those of neonates included gestational age, birth weight, race, sex, and Apgar scores. Standard statistical proedures were applied to analyze the data. Results: Chorioamnionitis (50% vs. 17.8%, P<0.001) and funisitis (20% vs. 4.4%, P=0.002) were more common in term infants. Placental infarction rate was insignificantly higher in LPT infants (25.6% vs. 14.3%, P=0.08). The mothers in the LPT group were older (30.4 years vs. 28.1 years, P=0.05; odds ratio [OR], 1.06; 95% confidence interval [CI], 0.998-1.12, P=0.056) and more often suffered from hypertension (28.9 vs. 12.9 %, P=0.02), and received magnesium sulfate (48.9 vs. 20%, P< 0.001; OR, 2.86; 95% CI, 1.12-7.29, P<0.05). Duration of rupture of membrane was higher in term infants (13.6 hours vs. 9.1 hours, P<0.001). Chorioamnionitis (OR, 0.33; 95% CI, 0.13-0.79; P<0.05) was associated with a lower risk of LPT delivery. Conclusion: Placental infection is not a risk factor for LPT births. There is a nonsignificant predominance of vascular anomalies in LPT placentas. Higher maternal age, magnesium sulfate therapy, and maternal hypertension are clinical risk factors for LPT labor.

• Radiation Oncology Journal
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• 제31권3호
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• pp.147-154
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• 2013

Purpose: To evaluate the role of salvage radiotherapy (RT) for the treatment of regional lymph node recurrence (RLNR) after radical surgery in advanced gastric cancer. Materials and Methods: We retrospectively analyzed medical records of 26 patients who underwent salvage treatment after diagnosis of RLNR between 2006 and 2011. Patients with peritoneal seeding or distant metastasis were excluded. Eighteen patients received RT with or without chemotherapy and the other 8 did chemotherapy only without RT. A three-dimensional conformal RT was performed with median dose of 56 Gy (range, 44 to 60 Gy). Sixteen patients had fluoropyrimidine-based chemotherapy, 5 did taxane-based chemotherapy, and irinotecan was applied in 4. Results: With a median follow-up of 20 months (range, 5 to 57 months), median overall survival (OS) and progression-free survival (PFS) after diagnosis of RLNR were 29 months and 12 months in the entire patients, respectively. Radiotherapy (p = 0.007) and disease-free interval (p = 0.033) were statistically significant factors for OS in multivariate analysis. Median OS was 36 months in patients who received RT and 16 months in those who did not. Furthermore, delivery of RT (p < 0.001), complete remission after salvage treatment (p = 0.040) and performance status (p = 0.023) were associated with a significantly better PFS. Gastrointestinal toxicities from RT were mild in most patients. Conclusion: Salvage RT combined with systemic chemotherapy may be an effective treatment managing RLNR from advanced gastric cancer.

• Journal of Periodontal and Implant Science
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• 제38권sup2호
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• pp.355-362
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• 2008

Purpose: The carrier for the delivery of bone morphogenetic proteins(BMPs) should also serve as a scaffold for new bone growth. In addition, predictable bone formation in terms of the volume and shape should be guaranteed. This study evaluated the ectopic bone formation of recombinant human BMP-2(rhBMP-2) using a micro macroporous biphasic calcium phosphate (MBCP: mixture of ${\beta}TCP$ and HA) block as a carrier in a rat subcutaneous assay model. Materials and Methods: Subcutaneous pockets were created on the back of 40 male Sprague-Dawley rats. In the pockets, rhBMP-2/MBCP and MBCP alone were implanted. The blocks were evaluated by histological and histometric parameters after a healing interval of 2 weeks (each 10 rats; MBCP and rhBMP-2/MBCP) or 8 weeks (each 10 rats; MBCP and rhBMP-2/MBCP). Results: The shape and volume of the block was maintained stable over the healing period. No histological bone forming activity was observed in the MBCP alone sites after 2 weeks and there was minimal new bone formation at 8 weeks. In the rhBMP-2/MBCP sites, new bone formation was evident in the macropores of the block. The new bone area at 8 weeks was greater than at 2 weeks. There was a further increase in the quantity of new bone with the more advanced stage of remodeling. Conclusions: A MBCP block could serve as a carrier system for predictable bone tissue engineering using rhBMPs.

• Advances in pediatric surgery
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• 제3권1호
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• pp.15-23
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• 1997

During a 6-year period, from January 1990 to December 1995, 101 neonates with congenital anomalies were admitted to the division of Pediatric Surgery of Youngdong Severance Hospital. All of them had prenatal screening more than once with ultrasound. Fifty eight of them had prenatally detectable anomalies by ultrasonography. However abnormalities were prenatally detected in 24 neonates(41%). The detection rate was 70% in patientws who had the prenatal screening at our hospital, whereas, the rate was 24% when it was performed at other medical facilities. Duodenal and jejuno-ileal atresia showed the highest detection rate(86%) followed by abdominal mass. Esophageal atresia was suggested by maternal polyhydramnios in 3 patients (25%). Only one patient with diaphragmatic hernia(1.75%) was prenatally detected and none with gastroschisis. The mean interval from birth to operation was 32 hours in the prenatally detected patients and 50 hours in the non detected. The complication rate and the mortality after emergency operation were 20% and 7% in the detected group, and 58% and 23% in the nondetected, respectively. The average period of the hospitalization was 20 days in the detected group and 39 days in the nondetected. We conclude that the prenatal detection of anomalies is necessary to ensure adequate care for the mothers and the babies with congenital anomalies. This includes early transfer, timing of optimal delivery and operation.

• 대기
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• 제27권2호
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• pp.189-197
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• 2017

Progressing from weather forecasts and warnings to multi-hazard impact-based forecast and warning services represents a paradigm shift in service delivery. Urban flooding is a typical meteorological disaster. This study proposes support plan for urban flooding impact-based forecast by providing inundation risk matrix. To achieve this goal, we first configured storm sewer management model (SWMM) to analyze 1D pipe networks and then grid based inundation analysis model (GIAM) to analyze 2D inundation depth over the Gangnam drainage area with $7.4km^2$. The accuracy of the simulated inundation results for heavy rainfall in 2010 and 2011 are 0.61 and 0.57 in POD index, respectively. 20 inundation scenarios responding on rainfall scenarios with 10~200 mm interval are produced for 60 and 120 minutes of rainfall duration. When the inundation damage thresholds are defined as pre-occurrence stage, occurrence stage to $0.01km^2$, 0.01 to $0.1km^2$, and $0.1km^2$ or more in area with a depth of 0.5 m or more, rainfall thresholds responding on each inundation damage threshold results in: 0 to 20 mm, 20 to 50 mm, 50 to 80 mm, and 80 mm or more in the rainfall duration 60 minutes and 0 to 30 mm, 30 to 70 mm, 70 to 110 mm, and 110 mm or more in the rainfall duration 120 minutes. Rainfall thresholds as a trigger of urban inundation damage can be used to form an inundation risk matrix. It is expected to be used for urban flood impact forecasting.

• 한국환경과학회지
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• 제19권6호
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• pp.665-670
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• 2010

Pollutants from urban pavement consists various kinds of substances which are originated from dry deposition, a grind out tire, corrosive action of rain to pavement and facilities and raw materials of the road etc.. These are major pollutants of urban NPS (Non-point source) during rainfall period. However there is not enough information to control such pollutants for appropriate management of natural water quality. In this study of transportation areas, three monitoring stations were set up at trunk road, urban highway and national road in Gyeongnam province. Runoff flow rate was measured at every 15minutes by automatic flow meters installed at the end of storm sewer pipe within the road catchment area for water quality analysis. Data was collected every 15 minutes for initial two hours of rainfall. Additional samples were collected 1-4 hours interval till the end of rainfall. The monitoring parameters were $COD_{Mn}$, SS, T-N & T-P and heavy metals. The average EMCs of TSS and $COD_{Mn}$ were 62.0 mg/L and 24.2 mg/L on the city trunk road, which were higher than those of urban highway and national road, indicating higher pollutant loads due to activities in the city downtown area beside the vehicle. On the other hand, the average EMC of T-N and T-P were in the range of 2.67-3.23 mg/L and 0.19-3.21 mg/L for all the sampling sites. Heavy metals from the roads were mainly Fe, Zn, Cu and Mn, showing variable EMCs by the type of road. From the TSS wash-off analysis in terms of FF(first flush) index, first flush phenomenon was clearly observed in the trunk road(FF : 0.89-1.43). However, such mass delivery behavior was not apparently shown in urban highway(FF : 0.90-1.11) and national road(FF : 0.81-1.41).