• The Korean Journal of Nuclear Medicine
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• v.30 no.4
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• pp.507-515
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• 1996

Background : Potassium channel opener (K-opener) opens ATP-sensitive K'-channel located at cell membrane and induces potassium efflux from cytosol, resulting in intracellular hyperpolarization. Newly synthesized K-opener is currently examined for pharmacologic potency by means of rubidium release test from smooth muscle strip pre-incubated with Rb-86. Since in-vivo behavior of thallium is similar to that of rubidium, we hypothesized that K-opener can alter T1-201 kinetics in vivo. Purpose : This study was prepared to investigate the effects of pinacidil (one of potent K-openers) on the T1-201 uptake and clearance in cultured myocyte, and in-vivo biodistribution in mice. Methods : Spontaneous contracting myocytes were prepared to imitate in-vivo condition from 20 hearts of 3-5 days old Sprague-Dawley rat and cultured for 3-5 days before use ($5{\times}10^5$ cells/ml). Pinacidil was dissolved in 10% DMSO solution at a final concentration of 100nM or l0uM and was co-incubated with T1-201 in HBSS buffer for 20-min to evaluate its effect on cellular T1-uptake, or challenged to cell preparation pre-incubated with T1-201 for washout study. Two, 40 or $100{\mu}g$ of pinacidil was injected intravenously into ICR mice at 10 min after $5{\mu}Ci$ T1-201 injection, and organ uptake and whole body retention rate were measured at different time points. Results : Co-incubation of pinacidil with T1-201 resulted in a decrease in T1-201 uptake into cultured myocyte by 1.6 to 2.5 times, depending on pinacidil concentration and activity of T1-201 used. Pinacidil enhanced T1-201 washout by 1.6-3.1 times from myocyte preparations pre-incubated with T1-201. Pinacidil treatment appears to be resulted in mild decreases in blood and liver activity in normal mice, in contrast, renal and cardiac uptake were mildly decreased in a dose dependent manner. Whole body retention ratios of T1-201 were lower at 24 hour after injection with $100{\mu}g$ of pinacidil than control. Conclusion : These results suggest that treatment with K-opener may affect the interpretation of T1-201 myocardial images, due to decreasing thallium accumulation and enhancing washout from myocardium.

• Restorative Dentistry and Endodontics
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• v.27 no.2
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• pp.142-149
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• 2002

Low-viscosity composite resins may produce better sealed margins than stiffer compositions (KempScholte and Davidson, 1988: Crim, 1989). Plowable composites have been recommended for use in Class V cavities but it is also controversial because of its high rates of shrinkage. On the other hand, in the study comparing elastic moduli and leakage, the microfill had the least leakage (Rundle et at. 1997) Furthermore, in the 1996 survey of the Reality Editorial Team, microfills were the clear choice for abfraction lesions. The purpose of this study was to evaluate the microleakage of 6 compostite resins (2 hybrids, 2 microfills, and 2 flowable composites) with and without load cycling. Notch-shaped Class V cavities were prepared on buccal surface of 180 extracted human upper premolars on cementum margin. The teeth were randomly divided into non-load cycling group (group 1) and load cycling group (group 2) of 90 teeth each. The experimental teeth of each group were randomly divided into 6 subgroups of 15 samples. All preparations were etched, and Single bond was applied. Preparations were restored with the following materials (n=15) : hybrid composite resin [Z250(3M Dental Products Inc. St. Paul, USA), Denfil(Vericom, Ahnyang, Korea)], microfill [Heliomolar RO(Vivadent, Schaan, Liechtenstein), Micronew(Bisco Inc. Schaumburg, IL, USA)], and flowable composite［AeliteFlo(Bisco Inc. Schaumburg, IL, USA), Revolution(Kerr Corp. Orange, CA, USA)]. Teeth of group 2 were subjected to occlusal load (100N for 50,000 cycles) using chewing simulator(MTS 858 Mini Bionix II system, MTS Systems Corp. Minn. USA). All samples were coated with nail polish 1mm short of the restoration, placed in 2％ methylene blue for 24 hours, and sectioned with a diamond wheel. Enamel and dentin/cementum margins were analyzed for microleakage on a sclale of 0 (no leakage) to 3 (3/3 of wall). Results were statistically analyzed by Kruscal-Wallis One way analysis, Mann-Whitney U-test, and Student-Newmann-Keuls method. (p = 0.05) Results : 1. There was significantly less microleage in enamel margins than dentinal margins of all groups (p＜0.05) 2. There was no significant between six composite resin in enamel margin of group 1. 3. In dentin margin of group 1, flowable composite had more microleakage than others but not of significant differences. 4. there was no significant difference between six composite resin in enamel margin of group 2. 5. In dentin margin of group 2, the microleakage were R＞A =H=M＞D＞Z. But there was no significant differences. 6. In enamel margins, load cycling did not affect the marginal microleakage in significant degree. 7. In enamel margins, load cycling did affect the marginal microleakage only in Revolution. (p＜0.05).

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.2
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• pp.262-269
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• 2002

The purpose of this study was to compare the effect of distance of light tip to resin surfaces and exposure time on the polymerization of surface and 2 mm subsurface of composite resins cured with two light sources; conventional halogen light (XL 3000, 3M, U.S.A.) and plasma arc light (Flipo, LOKKI, France) and compare the uniformity of polymerization from the center to the periphery of resin surfaces according to polymerization diameter cure with two light sources. From the experiment, the following results were obtained. 1. Difference of relative light intensity decrease in plasma arc light smaller than that of conventional halogen light(p<0.05). 2. In all groups, microhardness of top surfaces was decreased when distance of the light tip to resin surfaces is more than 2mm and increased according to increase of exposure time(p<0.05). 3. Difference of microhardness of the 2mm subsurface was rapidly decreased when distance of light tip to resin surfaces is more than 4mm(except, plasma arc light exposure time of 3 seconds). and the distance of light tip to resin surfaces and exposure time more affected 2mm subsurface rather than top surface(p<0.05). 4. Although exposure time was increased, difference of microhardness of the 2mm subsurface with the distance of light tip to resin surfaces was relatively high in groups between below 4mm and 6 mm(p<0.05). 5. Plasma arc light exposure time of 6 to 9 seconds produced microhardness values and microhardness change according to various distance similar to those produced with 40 to 80 second exposure to a conventional halogen light(p>0.05). 6. In all groups, microhardness was decreased gradually from the center to the periphery of resin surfaces(p<0.05).

• Tuberculosis and Respiratory Diseases
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• v.48 no.3
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• pp.357-364
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• 2000

Background : Complicated exudative pleural fluid collections have traditionally been treated by either closed tube thoracostomy drainage or by open surgical drainage. Complete drainage is important in order to control pleural sepsis, restore pulmonary function, and entrapment. Recently intracavitary fibrinolytic therapy has been advocated as a method to facillitate drainage of complicated exudative pleural effusion and to allow enzymatic debridemant of the restrictive fibrinous sheets covering the pleural surface. The purpose of this study is to prospectively evaluate the effects of image-guided catheter drainage with high dose urokinase(UK) instillation in the treatment of complicated pleural effusions. Patients : Twenty complicated pleural effusion patients that poorly respond to image-guided drainage were allocated to receive UK. There were 8 pneumonia and 12 tuberculosis. Methods : Drugs were diluted in 250 mL normal saline and were infused intrapleurally through the chest tube or pig-tail catheter in a daily dose of 250,000 IU of UK. Response was assessed by clinical outcome, fluid drainage, chest radiography, pleural ultrasound and/or computed tomography. Results : The mean UK instillation time was $1.63{\pm}0.10$. The mean volume drained UK instillation was $381.3{\pm}314.4\;mL$, and post-UK was $321.6{\pm}489.5\;mL$. The follow up duration after UK therapy was mean $212.9{\pm}194.5$ days. We had successful results in 19 cases (95.0%). There were 12 pleural thickenings (60.0%), 2 markedly decreased effusions (10.0%) and 5 cases of no thickening or effusion. There was recurrence after treatment in only one patient(5%) with complicated pleural effusiondue to tuberculosis. Conclusions : Image-guided drainage with high dose UK instillation (250,000 U/day) in complicated pleural effusion is a safe and more effective method than closed thoracostomy drainage. And this management, in turn, can obviate surgery in most cases.

• Korean journal of applied entomology
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• v.9 no.1
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• pp.25-32
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• 1970

This experiment was conducted to find out the simultaneous control effect of granulated insecticides on the several major rice insect pests in Korea. The granulated insecticides used were Terracur P$5\%$ (one of the phosphoric insecticides), Lebaycid $5\%$, and Sang-gamma (gamma-BHC) $6\%$. Those insecticides were broadcasted by hand on the paddy field at the ratio of 3kg. in June and 4kg. in August per 10 a, and the date of insecticidal application was based on the maximum moth occurrence of the rice stem borer in 1969. The rice insect pests tested in this study were rice stem borer (Chilo suppressalis W.), green rice leafhopper (Nephotettix bipunctatus cincticeps U.), smiller brown planthopper (Laodelphax striatellus F.), and white back planthopper (Sogotella furcifera H.). For the study of residual effectiveness of the insecticides, the rice stem borer larvae just hatched from the eggs were installed on the sheath of rice plants collected from the paddy field after insecticidal treatment, and the mortality was made at 48 hours after installation. High mortality was observed in Terracur P and Sang-gamma treatments and low mortality in Lebaycid treatment. The duration of residual effects giving about 50% mortality was about 14 days in Sang-gamma and about 6 days in Terracur P treatments. The study on the effectiveness of the insecticides to the rice stem borer in the paddy field was made by the number of dead blades and white heads of the rice plants injured by the larvae, and the number of survival larvae in the straws after crop harvest. The order of insecticidal effectiveness to the rice stem borer was Terracur P=Sang-gamm>Lebaycid. The study on the effectiveness of the insecticides to the leafhoppers and planthoppers in the paddy field was made by the population density by sweeping (5 times) at the given day intervals after treatments. Terracur P was highly effective for the control of the green rice leafhoppers and Lebaycid was moderately effective, but Sang-gamma seemed not to be effective. The effectiveness of the insecticides tested to the planthoppers was not clear, and it seemed to related with the low insect population density. Study on the determination of proper timing of insecticidal application was not also made clear, and it seemed to be short in the range of day intervals in the insecticidal application. For the study on the control effects of the rice insect pests, rice yield per 100 hills per plot was observed. There was no statistically significant difference among the treatments in rice yields, but the order of yield (Terracur P>Sang-gamma>Lebaycid>Control) was paralleled with the tends of control effects above mentioned. In a view point of simultaneous control of the rice stem borers and green rice leafhoppers by the application of granulated insecticides, Terracur P and Lebaycid were more effective than Sang-gamma which have been used.

• Korea journal of population studies
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• v.21 no.1
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• pp.184-228
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• 1998

This study reviews the relationship between son preference and fertility behavior, and infant and chlid mortality in the context of fertility and mortality decline. In Korea the situation reveals that fertility can decline to a very low level even in the presence of strong son preference, but son preference has certain effects on fertility and childhood mortality. The effect of son preference on fertility increased as the level of fertility declined. Our findings show that son preference causes excess female childhood mortality both directly and indirectly through fertility. Also, in Korea, the analysis reveals that female children suffer excessively high level of mortality and part of the excess mortality is due to parents' behavior on family building related to the effort to secure the birth of a son.

• Journal of Veterinary Clinics
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• v.20 no.1
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• pp.1-6
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• 2003

Immunoenhancing effects of conjugated linoleic acid (CLA) isomers (l0t-l2c CLA, 9c-11t CLA, CLA mixture, 9c-11c CLA and 9t-11t CLA) on chemotactic activity of porcine peripheral blood polymorphonuclear cells (PMN) were examined. The chemotactic activity of PMN was evaluated by a modified Boyden chamber assay. CLA isomers at higher concentration of 50 to 200$\mu$M exhibited a low viability of cells by trypan blue exclusion. CLA isomers were used at concentration of 20uM showing no cytotoxic effect and high cell viability. CLA isomers themselves were not active or slight chemotactic for PMN. But culture supernatant from mononuclear cells (MNC) treated with 10t-12c CLA, 9c-11t CLA and CLA mixture except for 9c-11c. CLA and 9t-11t CLA enhanced remarkably chemotactic activity or porcine PMN PMN migration by culture supernatant from MNC treated with CLA mixture was found to be true chemotaxis by checkboard assay. This migration was also induced by porcine recombinant interleukin (rIL)-8. PMN chemotaxis caused both culture supernatant from MNC treated with CLA mixture and porcine rIL-8 was inhibited in a dose-dependent manner by addition of anti-porcine IL-8 polyclonal antibody. Therefore, these results strongly suggested that CLA (10t-12c CLA, 9c-11t CLA and CLA mixture) could stimulate porcine MNC to release and IL-8 like chemotactic activity.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.6
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• pp.467-473
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• 2007

The most important factor for successful implantation is osseointegration between the implant and bone. The expression of bone morphogenetic proteins (BMPs) inducing bone formation would differ after maxillary sinus elevation. And within the same graft material. the expression of BMPs would change with time after graft. The aim of this study was to compare the relative expressions of BMP4 and BMP6 using real-time RT-PCR when maxillary sinus elevation was performed using deproteinated bovine bone powder (DBBP) as the graft material or absorbable gelatin sponge (AGS) as the filler without any graft material. Fifteen rabbits, each weighing between 3.0 to 3.5 Kg, were divided randomly into 5 groups of 3 animals each based on their time of sacrifice 0, 3, 5, 7 and 9 days). After exposure of the maxillary sinus bilaterally, bone graft was performed in the right maxillary sinus using DBBP ($BBP^{(R)}$ Oct Inc., Cheonan, Korea) and only AGS ($Gelfoam^{(R)}$ Pharmacia & Upjohn Company, Kalamazoo, MI, U.S.A) was placed into the left without any graft material. Each group of rabbits was sacrificed at 1, 3, 5, 7, or 9 days after operation and all specimens were harvested. And the following results were obtained using real-time RT-PCR from isolated total RNA of the samples. 1. The expression of BMP4 increased at postoperative 1 and 3 days in both DBBP group and AGS group. In AGS group. it decreased at postoperative 5 days. increased again at postoperative 7 days, and decreased at postoperative 9 days. In DBBP group, it increased until postoperative 7 days and decreased at postoperative 9 days. Although the expression of BMP4 was higher in DBBP group compared with AGS group, it was not statistically significant (p>0.05). 2. The expression of BMP6 increased at postoperative 1 and 3 days in both DBBP group and AGS group. In AGS group, it decreased at postoperative 5 days, increased again at postoperative 7 days, and decreased at postoperative 9 days. In DBBP group, it increased until postoperative 7 days and decreased at postoperative 9 days. Although the expression of BMP6 was higher in AGS group compared with DBBP group, it was not statistically significant (p>0.05). 3. There was no statistically significant difference in BMP expression in both groups during same period of time. It' s probably because DBBP and AGS both functioned as a space retainer so that the BMP expression in blood clot seemed to be similar. 4. Thus, DBBP would not offer many benefits for early bone regeneration compared with AGS. The expression of BMP in early bone formation seems to be more influenced by physical carrier rather than the graft type.

• Advances in pediatric surgery
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• v.13 no.2
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• pp.203-211
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• 2007

A nationwide survey on acute appendicitis (AAP) was undertaken among members of the Korean Association of Pediatric Surgeons. The members were required to complete a questionnaire and the case registration form for each patient during the 6 months period from the $1^{st}$ October, 2005 to $31^{st}$ March, 2006. Questionnaires were collected from 23 members. Four hundred seventy six patients were registered from 21 hospitals where the members were working. The male to female ratio was 1.67:1. Average age was 9 years and 5 months (range 21 months-20 years). Operations were performed on average 10.4 hours (range 1-230 hours) from arrival at hospital. The average operation time was 59.1 minutes. The average admission days were 5.8 days (range 2-45 days). The most frequent symptoms were abdominal pain (95.1 %), vomiting (50.6 %) and fever (43.7%). The average duration of symptoms was 42.2 hours (range 1 hour-22 days). Leukocytosis (WBC count > 10,000) was found in 85.9%. The most popular diagnostic tools were ultrasonography and CT. Open surgery was performed in 72.1 % and laparoscopic surgery in 27.5 %. Two laparoscopic surgeries were converted to open surgery (0.4 %). Simple appendicitis was found in 54.5 % and complicated appendicitis such as abscess, gangrenous change and perforation in 45.5%. According to the questionnaires 12 hospitals were performing open surgery only in all patients. Four hospitals were performing laparoscopic surgery in all patients. Seven hospitals are performing both surgical methods according to surgeon or occasion. Regarding the use of antibiotics in acute appendicitis, three kinds of antibiotics were used in 40 % of total simple appendicitis patients. The results showed the trend of management in acute appendicitis in Korea. Especially it is necessary for the members to discuss the use of antibiotics for prophylaxis in the simple appendicitis.

• Korean journal of applied entomology
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• v.47 no.2
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• pp.155-162
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• 2008

The Welsh onion beet armyworm, Spodoptera exigua (Hubner), has attacked Welsh onion and is now the most important pest of Welsh onion in southwestern Korea. The beet armyworm has a wide host range, occurring as a serious pest of vegetable and fields. The relatively high abundance of beet armyworm has stimulated frequent application of insecticides to foliage. Insecticide resistance is a major problem in management of this insect. Accordingly, pesticide application for the control of beet armyworm was tried in both the open field and in laboratory, using 4 synthetic compounds such as metaflumizone and chlorfenapyr, indoxacarb, flufenoxuron, emamectin benzoate. In the laboratory, each developmental stages from eggs, larva to pupa was tested against 4 insecticides. Against the eggs of welsh onion beet armyworm, there was no significantly different with each other. These tested chemicals no killing effect to eggs. However, the population of 1st larva hatched from eggs were reduced because they eaten the egg shell with residual insecticides. The tested insecticides were taken very high mortalities to 1st to 3rd larva of Welsh onion beet armyworm. Otherwise, there were decreased the death rate from 4th to 6th larva. On the other hand, their value of control effects were relatively good against Welsh onion beet armyworms in the field between 87.2 and 90.5% on 10 days after insecticide application.