• Restorative Dentistry and Endodontics
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• 제16권2호
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• pp.18-32
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• 1991

The purpose of this study was to observe characteristic properties of amalgam through the polarization curves and SEM images from 4 type amalgams (Amalcap, Shofu spherical. Dispersalloy and Tytin) with 3 different surface finish procedures (polishing, burnishing and carving) by using the potentiostats (EG & GPARC) and SEM (Jeol JSM-35). After each amalgam alloy and Hg was triturated as the direction of the manufacturer by means of mechanical amalgamator (Samki), the triturated mass was inserted into the cylndrical metal mold which was 12 mm in diameter and 10 mm in height and was pressed with $100kg/cm^2$. 4 specimens of each type amalgam were burnished with egg burnisher and another 4 specimens of each type amalgam were carved with Hollenback carver. Above 8 specimens and remaining untreated 4 specimens were stored at room temperature for about 7 days. Untreated 4 specimens of each type amalgam were polished with abrasive papers (Deer) from #400 to #1200 and finally on the polishing cloth with $0.5{\mu}m$ and $0.06{\mu}m$ $Al_2O_3 $ powder suspended water. Anodic polarization measurements was employed to compare the corrosion behaviours of the amalgams in 0.9% saline solution at $37^{\circ}C$. The open circuit potential was determined after 30 minutes immersion of specimen in electrolyte. The scan rate was 1 mV/sec and the surface area of amalgam exposed to the solution was $0.64cm^2$ for each specimen. All the potentials reported are with respect to a saturated calomel electrode (SCE). SEM images of each specimen were taken after + 800 mV (SCE) polarization. The results were as follows: 1. The corrosion potential of high copper amalgam was more anodic than that of low copper amalgam. 2. The polished amalgam were more resistant to corrosion than any other burnished and carved amalgam. 3. In the case of polishing, current density of high copper amalgam was lower than that of low copper amalgam.

• Genomics & Informatics
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• 제5권4호
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• pp.174-178
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• 2007

The earliest stages of mammalian embryogenesis are governed by the activity of maternally inherited transcripts and proteins. Cytoplasmic polyadenylation of selected maternal mRNA has been reported to be a major control mechanism of delayed translation during preimplantation embryogenesis in mice. The presence of cis-elements required for cytoplasmic polyadenylation (e.g., CPE) can serve as a useful tag in the screening of maternal genes partaking in key functions in the transcriptionally dormant egg and early embryo. However, due to its relative simplicity, UA-rich sequences satisfying the canonical rule of known CPE consensus sequences are often found in the 3'-UTR of maternal transcripts that do not actually undergo cytoplasmic polyadenylation. In this study, we developed a method to confirm the validity of candidate CPE sequences in a given gene by a multiplex comparison of 3'-UTR sequences between mammalian homologs. We found that genes undergoing cytoplasmic polyadenylation tend to create a conserved block around the CPE, while CPE-like sequences in the 3'-UTR of genes lacking cytoplasmic polyadenylation do not exhibit such conservation between species. Through this cross-species comparison, we also identified an alternative CPE in the 3'-UTR of tissue-type plasminogen activator (tPA), which is more likely to serve as a functional element. We suggest that verification of CPEs based on sequence conservation can provide a convenient tool for mass screening of factors governing the earliest processes of mammalian embryogenesis.

• International Journal of Industrial Entomology and Biomaterials
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• 제16권2호
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• pp.37-48
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• 2008

The diapause and non diapause associated proteins of multivoltine silkworm eggs were analysed by two dimensional (2D) gel electrophoresis. The study was made at 0 hr, 24 hrs and 48 hrs after oviposition. A total of four protein spots in diapause eggs at 24 hrs of oviposition and two protein spots in non diapause eggs at 0 hrs of oviposition were observed. All the six protein spots were considered to have association with diapause and non diapause characters. The molecular weight (MW) and isoelectric point (PI) of these 6 protein spots were calculated. The protein spots 1 and 2 observed in 0 hr of non diapause eggs were found to have the MW of 67 and 75 KDa and PI of 8.6 and 8.4 respectively. Similarly the four protein spots observed in diapause egg at 24 hrs of oviposition exhibited MW viz., 15, 17,20 and 25 KDa and PI of 5.3, 5.8, 6.5 and 6.0 respectively. All these 6 identified protein spots were subjected to in-gel digestion and resulted tryptic peptides were analyzed by Matrix-assisted laser desorption/ionization time-of flight mass spectrometry (MALDI TOF-MS). Databases searched based on experimentally determined molecular weights of peptides for the determination of the identities of proteins. The identified proteins indicated homology of 34% to 95%. The results indicate that the proteins may playa role in development of diapause and non diapause eggs.

• Parasites, Hosts and Diseases
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• 제22권1호
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• pp.61-65
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• 1984

1983년 12원부터 1984년 3월까지 서울에서 실시한 대편검사에서, Fibricola seculens심의 충란이 15명에게서 발견되었고, 이들을 Stoll씨 충란계산법으로 검사한 결과 EPG는 0∼500의 범위에 있었다. 이들 모두에게 Praziquantel을 20mg/kg의 용량으로 1회 투여하고, 그 중 9례를 대상으로 엄류하제를 이용하여 충체 수집을 시도하였다. 대상자 중 6례에서 F. seoulensis의 성충을 1∼78마리 수집할 수 있었다. 이들 15례에 대하여 치료 2∼6주후에 추적 검변한 결과 모두가 충란을 배출하지 않음을 확인하였다. 이들 감염자들은 임상적인 증상이 전혀 없었고, 따라서 임상검사는 시행하지 않았다. 이들은 모두가 20대 한국인 남자로, 출현의 일환으로 뱀 또는 개구리를 구워서 또는 날로 1회 이상 먹은 경험이 있었다. 이들이 마지막으로 뱀을 먹은 시기는 각각 1981년 9월에서 1983년 11일 사이에 있었다. 이들의 대변에서 발견된 충란중 100개를 계측한 결과 길이가 0.081∼0.102mm, 폭이 0.051∼0.063mrn이었다. 약절반에서 난잔(operculum)가 확인가능하였고 대부분의 경계선이 충란 장축에 비스듬하게 관찰되었다. 우리나라에서 뱀과 개구리를 먹는 민간의 습관을 고려하면 인체 fibricoliasis가 보다 널리 퍼져 있을 것으로 생각된다. 충란의 감별만으로도 진단이 가능할 것으로 판단되므로 앞으로 많은 증례의 발견이 기대된다.

• 한국수산과학회지
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• 제41권6호
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• pp.478-484
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• 2008

To elucidate the spawning behavior and early life history of Liobagrus mediadiposalis, mature male and female fish were collected from a branch of the Seomjin River. Spawning was induced by injecting hormones, and then the spawning process and development of fertilized eggs, larvae, and juveniles were observed. Observations of spawning behavior showed that the female established a territory and built a spawning nest, and frequently pressed on the upper ventral part of the male to release her eggs. When spawning was finished, the fish supplied fresh water to the egg mass using their pectoral and caudal fins. Hatching began 189 h 20 min after fertilization at $21.5-23.5^{\circ}C$ (mean $22.7^{\circ}C$). The mean total length (TL) of newly hatched larvae was 7.18-7.39 mm (mean 7.31 mm). Their mouth and anus were already open and they had 14+24=38 myotomes. Eighteen days after hatching, the larvae were 12.71-13.79 mm (mean 13.27 mm) in TL and the yolk sac was absorbed completely. At 35 days after hatching, when all the fin-rays had formed, the juveniles were 15.84-17.92 mm (mean 16.33 mm) in TL.

• 한국응용곤충학회지
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• 제33권4호
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• pp.207-215
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• 1994

벼멸구(Nilaparvata lugens)는 아시아의 중요한 벼해충이다. 현재의 방제법은 주로 살충제와 저항성 품종에 의존하고 있다. 한국에서의 가장 중요한 생물적 방제인자는 자연 발생하고 있는 mermithid선충의 한종인 Agamermis unka로 생각된다. 벼멸구에의 기생율이 비록 장소와 해에 따라 변이가 높다하더라도 Mermithid 선충은 기주의 생식력을 감소할 뿐만아니라결과적으로 기주티사를 가져오기 때문에 전망이 밝은 생물적 방제인자이다. Mermithid 선충은 벼멸구가 년 3~4년세대를 경과하는데 비하여년 1세대를 나나 Mermithid선충 암컷은 일시에 산란을 하지 않기 때문에 전세대의 많은 벼멸구가 기생된다. 본 Mermithid선충은 완전기생충으로 대량생산 기술이 아직 개발되지 않아 개체군 억제를위한 증대법을 단지 제한적인 범위에서 가능하다. 그러나 재배적 방법이나 저항성 품종의 이용, 살충제와의 혼용을 통한 자연발생 선충 개체군을 보존함으로서 효과적인 벼멸구의 종합방제를 이룰 수 있다.

• 대한수의학회지
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• 제51권3호
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• pp.193-201
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• 2011

An attenuated vaccine strain AVR1/08 of Korean respiratory type of infectious bronchitis virus (IBV) was developed by 89th passages of IBV D85/06 strain in chicken eggs. The AVR1/08 strain had higher virus titer at least 20 times ($10^{1.3}$) than the parent virus D85/06 by egg inoculation method. The AVR1/08 strain had a single point mutation (S to Y) at position 56 of spike protein of IBV compared to parent virus IBV D85/06 strain. The mutation was observed consistently at viruses after 47th passage in chicken eggs. The AVR1/08 strain showed no virulence even after 6 passages in chickens and all chickens inoculated induced anti-IBV antibody 14 days after vaccination. The AVR1/08 strain had broad protective efficacy against QX type Korean nephropathogenic virus (Q43/06 strain), KM91 type Korean nephropathogenic virus (KM91 strain) and Korean respiratory virus (D85/06 strain). In contrast, Massachusetts (Mass) type attenuated vaccine strain H120 showed protection of 37.5 to 50% against these three viruses. Our results indicate that the AVR1/08 strain has potential as an attenuated vaccine effective in controlling IBVs circulating in Korea.

• 한국식생활문화학회지
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• 제14권5호
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• pp.535-554
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• 1999

The present study was conducted to investigate the relation of eating behavior and food intake to 534 adolescents' obesity indices. Group means of relative body weight (RBW) were 93.66 for males and 97.12 for females. Body mass index(BMI) were 20.39 for males and 20.41 for females. Respondents were divided into 3 groups on the basis of RBW as an obesity index. Astonishingly, 44.76% of total respondents were underweight and 12.92% overweight and obese. 64.54% of respondents usually skipped their breakfasts and 24.23% their dinners. More males did not have their breakfasts than females. In contrast, more females skipped their dinners than males. A significant difference was found between males and females in their eating habits(p<.001) that should be changed. As their undesirable eating habits, males pointed out 'skipping meals', while females stressed 'overeating'. There were more overeating respondents in the overweight group, while more respondents skipping their meals were found in the underweight group. Many females(72.79%) and males(52.78%) tended to alternate consistently overeating and fasting to lose weight. The most important reason for losing weight was to improve their appearance(61.12%). In addition, nutrient score indices of respondents were very low with a mean of 33.39. Only 42.13% of total respondents showed good nutrient score indices. More males ate meat, bean, white vegetables, potato and fat than females(p<.05), whereas more females ate bread, rice cake and fruit than males(p<.01). Among the 3 groups -overweight, normal weight and underweight groups, overweight group was the most eaters of meat, fish, egg and milk; underweight group was the least eaters of them.

• 한국식품조리과학회지
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• 제29권5호
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• pp.563-571
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• 2013

This study surveyed food intake and preferences for breakfast among 167 male and 152 female middle school students in Incheon. Most students were in a normal range with respect to body mass index (BMI; 18~22.9). Most of the students spent 10~20 minutes to finish their breakfast, and female students skipped breakfast more frequently than male students, with major reasons of not being able to spend enough time for breakfast and low appetite. Steamed rice(bap) was the most frequently consumed food for breakfast. Students ate vegetables and fruits for breakfast the most frequently, followed by milk and milk products, meat, fish, egg and beans, and cereals. The most frequently consumed food among protein sources was eggs. Male students had foods except vegetables and fruits more frequently than female students for their breakfast. Female students were more highly aware of the importance of breakfast on their health than male students. Preference on different food groups was significantly higher in male students than female students except vegetable salad and fruit juices. The results suggest that breakfast skipping of middle school students can be reduced by aggressively reflecting food preferences of the students to breakfast menu and appropriate nutritional education for students and their mothers.

• The Plant Pathology Journal
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• 제30권3호
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• pp.288-298
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• 2014

We examined the efficacy of a bacterium for biocontrol of the root-knot nematode (RKN) Meloidogyne hapla in carrot (Daucus carota subsp. sativus) and tomato (Solanum lycopersicum). Among 542 bacterial isolates from various soils and plants, the highest nematode mortality was observed for treatments with isolate C1-7, which was identified as Bacillus cereus based on cultural and morphological characteristics, the Biolog program, and 16S rRNA sequencing analyses. The population density and the nematicidal activity of B. cereus C1-7 remained high until the end of culture in brain heart infusion broth, suggesting that it may have sustainable biocontrol potential. In pot experiments, the biocontrol efficacy of B. cereus C1-7 was high, showing complete inhibition of root gall or egg mass formation by RKN in carrot and tomato plants, and subsequently reducing RKN damage and suppressing nematode population growth, respectively. Light microscopy of RKN-infected carrot root tissues treated with C1-7 showed reduced formation of gall cells and fully developed giant cells, while extensive gall cells and fully mature giant cells with prominent cell wall ingrowths formed in the untreated control plants infected with RKNs. These histopathological characteristics may be the result of residual or systemic biocontrol activity of the bacterium, which may coincide with the biocontrol efficacies of nematodes in pots. These results suggest that B. cereus C1-7 can be used as a biocontrol agent for M. hapla.