• The Journal of Korean Academy of Prosthodontics
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• v.51 no.1
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• pp.11-19
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• 2013

Purpose: The aim of this study was to evaluate the heat generation in bone in vitro during the guided flapless drilling procedure and the effect of drilling methods on the heat generation. Materials and methods: A model that has missing the first and second mandibular molars bilaterally was used. In group A, classical flap implant surgery was performed. In group B, flapless implant surgery using surgical guide was performed. In group C, flapless implant surgery using surgical guide without up-and-down pumping motion was performed. Temperature was measured with k-type thermocouple and a real-time digital thermometer. The thermocouples were placed at 0.5 mm away from the osteotomy area at the depths of 3 mm and 6 mm. The measured values were evaluated with independent t-test. Results: The mean temperature generated was $27.2^{\circ}C$ ($SD{\pm}2.1^{\circ}C$) and $27.5^{\circ}C$ ($SD{\pm}2.3^{\circ}C$) for groups A and B, respectively. These differences were not statistically significant. In group C, the mean temperature was $37.0^{\circ}C$ ($SD{\pm}3.4^{\circ}C$). There were statistically significant differences between groups B and C with respect to the mean temperature. Conclusion: These findings suggest that guided flapless drilling with up-and-down pumping motion may not significantly increase the bone temperature.

• Neonatal Medicine
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• v.18 no.1
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• pp.96-103
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• 2011

Purpose: Although infants with bronchopulmonary dysplasia (BPD) are at risk of developing secondary pulmonary hypertension (PH), which is associated with significant morbidity and mortality, little has been reported about the incidence, clinical course and prognosis of PH secondary to BPD in premature infants. This study was done to investigate the incidence, risk factors, clinical course, and the ultimate prognosis of PH developed secondary to BPD in very low birth weight infants (<1,500 g). Methods: Medical records of very low birth weight infant (VLBWI) admitted to Samsung Medical Center NICU from January 2000 to July 2007 were reviewed retrospectively. BPD was defined by Jobe's classification. The diagnosis of pulmonary hypertension was established as velocity of tricuspid valve regurgitation (TR) ${\geq}$3 m/s and a flattening of the intraventricular septum by conducting Doppler echocardiography. Results: The incidence of pulmonary hypertension was 6% in VLBWI with BPD and it developed in moderate to severe BPD. The diagnosis of pulmonary hypertension was made on postnatal 133 days (range 40-224 days) and the risk factors related to developing pulmonary hypertension were severe BPD, small for gestational age and outborn infants. The mortality rate was 57% and especially higher in severe BPD (70%). The time to recovery spent 3 months (range 1-10 months) in survived patients. Conclusion: Based on the results of this research, pulmonary hypertension secondary to BPD in VLBWI related to severity of BPD and had a poor prognosis. We expect that regular long-term echocardiography may be helpful in treating reversible in VLBWI with moderate to severe BPD.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.5
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• pp.727-743
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• 1996

To know the floristic composition, vortical distribution and community structure of marine benthic algae inhabiting in the intertidal and subtidal zones of Yongil Bay, east coast of Korea, the study has performed using the quadrat method along a transect line from July, 1995 to June, 1996. In this area, a total of 144 species including 2 new red algae to Korea was found: 5 blue-green, 18 green, 20 brown and 101 red algae. The representative species throughout the year were Ulva pertusa, Gelidium amansii and Symphyocladia latiuscula. Dominant species were Sargassum thunbergii in spring, U. pertusa in summer and autumn. In winter, Chondrus ocellatus and Monostroma grevillei occurred dominantly. The standing crop exhibited mean value as $185.8g/m^2$ dry weight. Maximum value was recorded in spring $(267.3g/m^2)$ and minimum was observed in winter $(93.7g/m^2)$. Shannon's species diversity (H') and evenness (J') as maximum value were recorded in spring, whereas minimum values were shown in winter. Vertical distribution, rerognized by cluster analysis based on relative coverage of the species, could be divided into two or three algal groups except spring. In general, green algae (M. grevillei, Capsosiphon fulvescens, U. pefusa, Enteromorpha compressa) and brown algae (Sargassum fulvellum, S. thunbergii) were represented in the upper and middle zone and red algae (G. amansii, C. ocellatus, S. latiuscula, Crateloupia okamurae, Pachymeniopsis eilliptica) in the lower zone. The algal community varied according to season and environmental conditions. Particularly, seasonal variation of vortical distribution seemed to be affected primarily by water temperature. Also seasonal tidal level and tolerance of algal species to desiccation appeared to be associated with it in this area.

• Clinical and Experimental Pediatrics
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• v.53 no.2
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• pp.203-209
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• 2010

Purpose : Growth impairment is usually observed in children with congenital heart disease (CHD). Studies on the final height and weight of this population are insufficient. Our aim was to evaluate the final height of children with CHD and to identify the relationship between CHD and growth. Methods : We recorded the values of final height and weights of 105 CHD patients (age, <19 years) who visited Chonnam National University Hospital between November 2000 and March 2009, and we reviewed the medical records. Results : The mean values of weight and height of male CHD patients were significantly lower than those of the normal subjects. Patients with severe growth impairment (below the third percentile of normal) included 5 males (8.6%) and 4 females (8.5%) with height less than normal and 9 males (15.5%) and 8 females (17.0%) with weight less than normal. The mean growth of the patients in the cyanotic heart disease group was lower than that of normal subjects, but a statistically significant difference was noted in the weights of males. In a comparative study based on the type of CHD, a significant difference was noted in weights of males. Patients with patent ductus arteriosus and those with tetralogy of Fallot had the highest and lowest mean values of weight, respectively. Conclusion : Growth impairment was more evident in children with CHD than normal children. Patients should be treated during an optimal time frame. Thus, CHD patients should be treated if follow-up studies indicate growth impairment.

• Clinical and Experimental Pediatrics
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• v.52 no.3
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• pp.303-309
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• 2009

Purpose : To identify the short-term clinical outcomes of late preterm infants and to test the hypothesis that late preterm infants have more clinical problems during the early postnatal period than term infants. Methods : One hundred late preterm infants [gestational age (GA) $34^{+0}$-$36^{+6}$ weeks] and the same number of term infants (GA $37^{+0}$-$41^{+6}$ weeks) were randomly selected from 289 late preterm infants and 825 term infants born in the Seoul National University Bundang Hospital between January 2007 and December 2007, and their electronic medical records were reviewed and analyzed. Results : Compared to term infants, late preterm infants had significantly more medical problems such as temperature instability (odds ratio [OR] 8.7), hypoglycemia (OR 17.5), intravenous fluid infusion (OR 10.2), evaluation for sepsis (OR 9.4), respiratory problems (OR 7.5), apnea and bradycardia (OR 8.6), phototherapy for jaundice (OR 3.6), and feeding intolerance (OR 10.0). Hospital stay was also significantly longer in late preterm infants. Conclusion : Late preterm infants had significantly more medical problems and increased length of hospital stay compared to term infants. More attention should be given to caring for these late preterm infants in newborn nursery during the early postnatal period.

• Clinical and Experimental Pediatrics
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• v.48 no.2
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• pp.165-173
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• 2005

Purpose : We performed the study to evaluate the value of the follow-up echocardiogram performed 6 months to 1 year after the onset of Kawasaki disease(KD), as recommended by American Heart Association(AHA) guidelines, when echocardiograms in the convalescent period were normal. Methods : Patients were selected from 147 cases diagnosed with KD at Pusan Paik hospital from January 2000 to October 2003. A total of 45 KD patients belonged to AHA risk level I and II were performed follow-up echocardiography. The patient's medical records and echocardiogram were reviewed. Additionally, we sought the opinion of pediatric cardiologists on the subject by means of a multiple-choice survey. Results : 37 children were belonged to AHA risk level I and the remaining 8 patients were belonged to risk level II. Of these 45 children, none were noted to have abnormalities on later follow-up echocardiogram. In the results of questionnaire, 37 percent of the participants advocate no follow-up after convalescent period for risk level I, and 33.3 percent favor periodic follow-up with echocardiography for risk level II up to one year. But there were no consensus about the diagnostic criteria of coronary abnormalities and how to follow-up these patients. Conclusion : All children with KD should have an echocardiogram at present and a follow-up study 6 to 8 weeks after the onset of fever. However, additional echocardiographies are not justified if the 6- to 8-week follow-up echocardiogram is normal. We would recommend that the more reasonable diagnostic criteria for coronary abnormalities and the Korean guidelines for long-term cardiovascular management and follow-up of KD need to be established.

• Clinical and Experimental Pediatrics
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• v.45 no.12
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• pp.1559-1570
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• 2002

Purpose : There has been no exact answer to the question of when to discontinue antiepileptic drugs(AEDs) in children with well-controlled epilepsy for a long period. This study is about the risk factors of relapse after withdrawal of AEDs in seizure(Sz)-free patients to show a guideline for discontinuation of AEDs. Methods : One hundred and sixty-nine children were diagnosed as epileptic at the Pediatric Dept. of Kyung-Hee Univ. between 1993 to 1998, in whom AEDs had been withdrawn after at least two years of Sz-free period. Univariate analysis using Kaplan-Meier survival analysis and multivariate analysis using Cox-proportional hazard model were performed for sixteen risk factors. Results : Forty-nine of the 169 patients(28.9%) had recurrence of Szs. The mean follow-up after withdrawal of AEDs was 4.1 years, mean treatment period was 4.1 years, and the mean Sz-free period was 3.3 years. Factors associated with an increased risk of relapse were young age at onset, symptomatic Sz, Sz type in West and Lennox-Gastaut syndrome, neurologic deficit, longer Sz-controlling period, shorter total treatment period, number of AEDs used(more than one drug), age at withdrawal of AEDs, and Sz-free period less than two years in univariate analysis using Kaplan-Meier mothod. From multivariate analysis, the factors indicating a significantly higher relapse risk were pre-treatment period after first Sz attack, Sz-controlling period, Sz-free period, number of AEDs used, neurologic abnormalities. Conclusion : For epileptic children who were Sz-free for more than two years, and were more than six-years-old, the discontinuation of AEDs should be considered positively, according to age of onset, Sz type, age at withdrawal of AEDs, total treatment period, Sz-controlling period, number of AEDs used, etiology, neurologic deficit, and the wishes of the patients and the their parents.

• Clinical and Experimental Pediatrics
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• v.50 no.3
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• pp.248-254
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• 2007

Purpose : Inflammation plays a major role in the pathogenesis of RDS and BPD in the immature lung. We investigated the possible role of IL-10 and IL-12 in the cord blood of preterm newborns with RDS or BPD. Methods : Forty preterm newborns whose mothers received antenatal care at Ewha Womans University Mokdong Hospital between January 2003 to June 2005, and agreed to testing their cord blood samples were enrolled. The gestational ages were below 34 weeks. Cord blood level of IL-10 and IL-12 were determined by ELISA. We separated the patients into 2 groups (RDS group and non-RDS group, BPD group and non-BPD group) and compared the cytokine levels and clinical records of the groups. Results : Cord blood IL-10 level showed a significant inverse correlation with gestational age and birth weight (P=0.001, P=0.005). Preterm infants with RDS showed higher IL-10 level (1.0 vs 0.1 pg/mL; P=0.001) in the cord blood than those without RDS. The differences remained statistically significant after correction for the effect of gestational age between both preterm groups. Despite similar cord blood IL-10 levels, preterm infants with BPD showed no significant difference with those without BPD. Conclusion : Cord blood IL-10 levels are increased in preterm infants which may be due to the immuno-suppression occurring during pregnancy and to fetal immaturity because these levels are inversely correlated with the gestational age. So, Cord blood IL-10 level can be used as the predictor of RDS.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.485-493
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• 2003

To assess trans fatty acids (tFAs) intake of middle school students in Busan, behavior of having meals and 3 day's food record were surveyed in 800 subjects. 35.3% of subjects responded to twice a day in frequency of snack intake. Preferred snack items were ice cream (68.6%) and milk (57.0%). Subjects of dining out preferred jajangmyon (54.6%), seasoned chicken (50.5%), fried chicken (35-3%) in order when dined out. Mean daily tFAs intake of subjects was 1.68$\pm$0.04 g. Mean daily intake level of girls was 1.89$\pm$0.06 g which was significantly higher than that of boys, 1.40 $\pm$ 0.05 g (p<0.001). Naturally derived tFAs intake was 1.04$\pm$0.03 g which corresponded to 62.1% of total tFAs intake per day and industrially derived tFAs intake was 0.64 $\pm$ 0.02 g, 37.9% of total tFAs intake per day. Calorie percentage of tFAs was 0.8% and fat percentage of tFAs was 3.16%. The level of tFAs intake showed a significant difference with monthly allowance (p<0.05) and frequency of snack intake (p<0.001) in girls, which was not the case in boys. The main sources of tFAs were milk and dairy products (34.3%), bakeries (18.3%), and fish and meat products (16.2%), in order. From above results, we can conclude that tFAs intake of middle school student is not as much as that of Western teenagers. However, exact estimation of tFAs intake requires database of tFAs in broad range of processed foods commonly consumed in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.4
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• pp.360-369
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• 1987

The relationship between the catches of tuna and hydrographic conditions in South-East Pacific region (latitude $5^{\circ}N-12^{\circ}S$, longitude $135^{\circ}W-115^{\circ}W$) was investigated by using the catch data of tuna and Digital Bathythermograph (DBT) data from December 9, 1980 to April 2, 1981. The results are as follows : The study area were located in South Eguatorial Current regions including equatorial upwelling regions in $5^{\circ}N\;to\;12^{\circ}S$. The horizontal mean temperature at the depth of 10m on the first quarter months in the study area was about $25^{\circ}C$C and the salinity of those fishing areas ranged from 34.8 to $35.0\%_{\circ}$. Yellowfin tuna and bigeye tuna were mainly caught in SW vertical temperature profile type, which the depth of thermocline ranged from loom to 300m, and temperature difference of thermocline was about $12^{\circ}C$. The deeper the depth of thermocline, the more the catches of tuna. While albacore tuna was caught well in SS vertical temperature profile type which the temperature of thermocline ranged from $9^{\circ}\;to\;26^{\circ}C$ and its gradient was very smooth. The depth of 1 ml/l surface of dissoved oxygen content ranged from loom to 200m in the South-East Pacific between longitude $140^{\circ}W-100^{\circ}W$, but it was shallower than 100 m near the North-South American continent. The catches of bigeye tuna were larger than those of yellowfin tuna in South Equatorial Current region. As approaching to the South and North American continent, the catches of yellowfin tuna and bigeye tuna decreased because the thermocline becomes shallower and steeper and the depth of the 1 m1/1 surface of dissolved oxygen content became shallower.