• 한국어병학회지
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• 제34권2호
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• pp.201-212
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• 2021

Olive flounder (Paralichthys olivaceus) (Weight 110.9±17.1 g, length 22.3±1.2 cm) were exposed to waterborne nitrite at 0, 30, 60, 120, 240, 480 and 960 mg NO₂^-/L according to water temperature at 20℃ and 25℃ for 96 hours. The lethal concentration 50 (LC₅₀) of olive flounder, P. olivaceus exposed to waterborne nitrite was 513.87 mg NO₂^-/L at 20℃ and 208.35 mg NO₂^-/L at 25℃, which means a significant difference in LC₅₀ by the water temperature. Hemoglobin and hematocrit were significantly decreased by waterborne nitrite exposure. The inorganic component, plasma calcium, was significantly decreased, and the organic components such as plasma glucose and cholesterol were significantly decreased showing a similar tendency with calcium. In enzymatic components, the AST and ALP were also significantly decreased by nitrite exposure. The results of this study indicate that exposure to nitrite can affect the survival and hematological physiology of P. olivaceus, and the effect of exposure to nitrite had a significant effect on nitrite toxicity depending on the water temperature.

• 한국식품과학회지
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• 제33권2호
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• pp.178-183
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• 2001

신갈나무 잎 추출물의 항균력은 추출 온도별로는 $60^{\circ}C$에서 추출시 $30^{\circ}C$와 $90^{\circ}C$에 추출하는 것보다 약간 더 높은 활성을 나타내었으며 추출 용매별로는 에탄올로 추출한 경우가 물 또는 메탄올 추출물보다 대체로 높은 항균활성을 나타내었다. 신갈나무 잎 에탄올 추출물은 그람양성균인 B. cereus, S. aureus 그리고 L. monocytogenes균에 대하여 $62.5{\sim}125\;{\mu}g/mL$ 범위에서 최소저해농도를 나타내었으나 그람음성균인 S. typhimurium과 P. aeruginosa 균은 $250\;{\mu}g/mL$, E. coli O157:H7 균에 대하여는 $500\;{\mu}g/mL$ 이상에서 최소저해농도를 나타내었다. B. subtilis ATCC 6633균과 L. monocytogenes ATCC 19111균에 대한 젖산, 구연산, 초산 및 신갈나무 잎 에탄올 추출물의 최소저해농도는 두균모두 각각 2,500, 5,000, 1,250 및 $125\;{\mu}g/mL$이었으며 이들의 병용처리시 B. subtilis ATCC 6633균에는 효과가 없었으나 L. monocytogenes ATCC 19111균에 대하여는 상승항균효과를 나타내었다. 한편, 각각의 sub-lethal 농도에서 E. coli O157:H7 0019균에 대한 신갈나무 잎 에탄올 추출물과 유기산들과의 병용처리시 두 물질간에는 상승효과는 없는 것으로 나타났다.

• 농약과학회지
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• 제9권4호
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• pp.374-379
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• 2005

Imidaclopid의 아치사량 처리에 의한 복숭아혹진딧물의 생물적 특성에 미치는 영향을 조사하여 imidacloprid의 사용 약량을 줄일 수 있는 방안을 모색코자 본 시험을 수행하였다. 복숭아혹진딧물에 아치사 농도로 처리한 후 4일간 산자수를 조사하였으며, $LC_1$의 농도로 처리한 후 복숭아혹진딧물의 산자수는 8.8마리로 무처리 12.7마리와 유의성을 보이지 않았으나, $LC_{10}$, $LC_{30}$, $LC_{50}$ 등의 처리에서는 산자수가 각각 6.0, 5.1, 3.9마리로 무처리보다 적게 낳았다. 산자억제율도 52.7, 59.8, 69.3%로 농도가 높을수록 높았다. 복숭아 혹진딧물에 대한 처리방법별 기피효과는 침지처리가 관주처리보다 높았으며 농도가 높아질수록 더 크게 나타났다. 복숭아혹진딧물의 아치사량 처리 후 배설량은 침지처리에서는 농도가 높아질수록 적어졌다. 무처리 대비 배설억제율은 $80{\sim}96%$이었으며, 관주처리에서는 농도별 배설량 차이는 보이지 않았지만 무처리 대비 배설억제율은 97%이상을 보였다.

• Journal of Ginseng Research
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• 제44권2호
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• pp.222-228
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• 2020

Background: 20(S)-ginsenoside-Rg3 (C₄₂H₇₂O₁₃), a natural triterpenoid saponin, is extracted from red ginseng. The increasing use of 20(S)-ginsenoside Rg3 has raised product safety concerns. Methods: In acute toxicity, 20(S)-ginsenoside Rg3 was singly and orally administrated to Kunming mice and Sprague-Dawley (SD) rats at the maximum doses of 1600 mg/kg and 800 mg/kg, respectively. In the 26-week toxicity study, we used repeated oral administration of 20(S)-ginsenoside Rg3 in SD rats over 26 weeks at doses of 0, 20, 60, or 180 mg/kg. Moreover, a 4-week recovery period was scheduled to observe the persistence, delayed occurrence, and reversibility of toxic effects. Results: The result of acute toxicity shows that oral administration of 20(S)-ginsenoside Rg3 to mice and rats did not induce mortality or toxicity up to 1600 and 800 mg/kg, respectively. During a 26-week administration period and a 4-week withdrawal period (recovery period), there were no significant differences in clinical signs, body weight, food consumption, urinalysis parameters, biochemical and hematological values, or histopathological findings. Conclusion: The mean oral lethal dose (LD₅₀) of 20(S)-ginsenoside Rg3, in acute toxicity, is above 1600 mg/kg and 800 mg/kg in mice and rats, respectively. In a repeated-dose 26-week oral toxicity study, the no-observed-adverse-effect level for female and male SD rats was 180 mg/kg.

• 환경생물
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• 제41권4호
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• pp.427-438
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• 2023

Dichlofluanid는 해양환경 내 빠르게 분해되지만 농약 및 방오제로 사용되고 퇴적물에 쉽게 축적되어 지속적으로 해양환경으로 유입되고 있다. Dichlofluanid는 다양한 해양생물에게 독성영향을 미치는 것으로 알려져 있지만 해조류에 대한 독성연구는 충분히 보고되지 않았다. 따라서 우리나라의 주요 양식생물인 미역(Undaria pinnatifida) 암배우체의 생존율 및 상대성장률을 이용하여 dichlofluanid의 독성영향을 분석하였다. U. pinnatifida의 암배우체를 dichlofluanid (0, 1, 2, 4, 8, 16, 32 mg L^-1)에 노출하였고 암배우체 생존율의 무영향농도(NOEC), 최소영향농도(LOEC), 반수치사농도(LC₅₀)는 1, 2, 10.82(8.87~13.23) mg L^-1, 상대성장률의 NOEC, LOEC, 반수영향농도(EC₅₀)은 1, 2, 6.58 (6.03~7.17) mg L^-1로 분석되었다. 본 연구결과는 dichlofluanid에 대한 U. pinnatifida 암배우체의 독성영향을 평가하기 위한 중요한 참고자료로 활용될 것으로 기대된다.

• 한국산업보건학회지
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• 제8권2호
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• pp.272-288
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• 1998

The purpose of this study was to investigate the acute(4 hrs) and repeated-dose(6 hrs a day, 5 days a week, 8 weeks) toxic effects of 1-bromopropane(1-BP) on Sprague-Dawley (SD) rats which were treated by inhalation. The results were as follows ; 1. The median lethal concentration($LC_{50}$) was estimated 14,374 ppm(confidence limit 95% ; 13,624~15,596 ppm) in acute inhalation. Abnormal clinical signs related to the 1-BP were not observed with the acute inhalation dose. Gross findings of necropsy revealed no evidence of specific toxicity related to the 1-BP. 2. By sub-acute inhalation the body weights of male and female were significantly reduced(p<0.001) by the dose of 1,800 ppm compared with control group, while the relative weights of liver were significantly increased(p<0.001) in both sexes. However there were no significant variation in food consumption, urine biochemistry, hematology and blood biochemistry for the exposed rats compared with the control rats. Abnormal clinical signs and gross findings of necropsy related to the 1-BP were not shown. No toxicologic lesions were observed by the histopathological test.

• Journal of Veterinary Science
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• 제21권5호
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• pp.80.1-80.13
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• 2020

Background: In suckling piglets, transmissible gastroenteritis virus (TGEV) causes lethal diarrhea accompanied by high infection and mortality rates, leading to considerable economic losses. This study explored methods of preventing or inhibiting their production. Bovine antimicrobial peptide-13 (APB-13) has antibacterial, antiviral, and immune functions. Objectives: This study analyzed the efficacy of APB-13 against TGEV through in vivo and in vitro experiments. Methods: The effects of APB-13 toxicity and virus inhibition rate on swine testicular (ST) cells were detected using 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT). The impact of APB-13 on virus replication was examined through the 50% tissue culture infective dose (TCID₅₀). The mRNA and protein levels were investigated by real-time quantitative polymerase chain reaction and western blot (WB). Tissue sections were used to detect intestinal morphological development. Results: The safe and effective concentration range of APB-13 on ST cells ranged from 0 to 62.5 ㎍/mL, and the highest viral inhibitory rate of APB-13 was 74.1%. The log₁₀TCID₅₀ of 62.5 ㎍/mL APB-13 was 3.63 lower than that of the virus control. The mRNA and protein expression at 62.5 ㎍/mL APB-13 was significantly lower than that of the virus control at 24 hpi. Piglets in the APB-13 group showed significantly lower viral shedding than that in the virus control group, and the pathological tissue sections of the jejunum morphology revealed significant differences between the groups. Conclusions: APB-13 exhibited good antiviral effects on TGEV in vivo and in vitro.

• Journal of Microbiology and Biotechnology
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• 제6권2호
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• pp.103-109
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• 1996

Mn(II)+succinate decreased the carotenoid formation of the yeast Phaffia rhodozyma, probably by scavenging $O_2$. When duroquinone (DQ), an internal and external $O_2$ generator, was added to medium, P. rhodozyma produced more amount of carotenoids. The increased carotenoid production was destroyed by oxygen radical (OR) scavengers, ascorbate+Cu(II) and dimethylsulfoxide. When sub-lethal concentrations of $H_2O_2$ , an external OR source, and antimycin, an internal OR inducer, were used, the effect of $H_2O_2$ on carotenoid formation and composition was less significant than that of antimycin. Addition of superoxide dismutase, an external OR remover, rescued cells from death caused by the high concentration of DO. In this condition, the yeast culture showed an increase in carotenoid content. Addition of DQ into P. rhodozyma culture in the stationary phase did not increase carotenoid production. Therefore, carotenoid formation was stimulated by internal ORs in the growing yeast. It was probably due to release of catabolite repression on carotenogenesis in the yeast. Aeration was important for carotenoid production but was not as effective as the internal OR producer, DQ.

• 한국게임학회 논문지
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• 제9권4호
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• pp.81-88
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• 2009

본 논문에서는 유전자 알고리즘을 이용하여 액션 게임에서 지능 캐릭터의 경로 탐색 방법을 제안하였다. 실험방법으로는 유전자 알고리즘의 특성을 살려 이동 캐릭터가 최단 경로를 선택 할 뿐만 아니라 최적경로 탐색이 가능하도록 하였다. 이 때 염색체의 코드화를 그대로 적용할 경우 많은 치사 유전자가 발생하는데 이 문제를 DNA의 행동 특성의 스플라이싱 방법을 이용하여 해결하였다. 탐색 과정에서 여러 개의 후보 해를 생성하는 유전자 알고리즘의 특징을 이용해서 최단 경로 이외에 최적 경로를 1회의 처리로서 지능 캐릭터가 경로를 탐색하였다.

• 한국응용곤충학회지
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• 제13권2호
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• pp.89-92
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• 1974

집파리의 3-5영기용에 X-선을 조사시켜 불임유기 핵과에 관한 용치사율, 부화율 및 우화성충의 치사율에 대한 실험 결과를 다음과 같이 얻었다. 1. 용치사율의 Probit 회귀직선은 Y=2.776+1.948이었으며 반치사선량(LD50)은 12.2-13.1 kRad이었다. 2. 집파리 웅충에 대한 불임유기선량(SD90)은 3.1 kRad됐으며 LD50 선량을 고려 해볼때 충분히 이용가능한 선량으로 본다. 3. 우화성충 치사율은 4 kRad와 5 kRad에서 웅충이 자충 보다 현저히 높은 사충율을 보였다.