• 한국식품영양과학회지
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• 제14권3호
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• pp.253-258
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• 1985

흰쥐 정관 및 꼬리 동맥의 ${\alpha}_1-$및 ${\alpha}_2-$수용체, 그리고 prostaglandine과 관련해 NA 유리에 미치는 Cd의 영향을 관찰하여 다음과 같은 결과를 얻었다. 1. Cd 중독 흰쥐 정관에서 전기 자극에 대한 반응은 증가하였으며, Freq.50은 대조군보다 현저히 낮아졌으며 꼬리동맥의 반응은 감약되었다. 2. Cd 중독 정관에서 clonidine의 억제반응은 유의하게 감소하였으나 methoxamine 존재하의 전기 자극 반응은 영향을 받지 아니하였다. 3. $PGE_2$에 의한 억제작용은 Cd 중독군에서는 소실되었으나 꼬리 동맥에서 $PGE_2$의 억제효과는 Cd 중독으로 영향을 받지 아니하였다. 4. Cd 중독 꼬리 동맥에서 methoxamine 및 clonidine에 대한 수축반응은 최대 수축고가 현저히 낮아졌으나 $ED_{50}$치는 변화하지 아니하였다. 이상의 결과로 보아 Cd 중독시 정관에서 시냅스 전막 autoreceptor가 억제되어 교감 신경 흥분성이 증가함으로써 전기자극에 대한 반응이 항진되었다고 생각된다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 추계학술대회
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• pp.15-18
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• 2018

본 논문에서는 교육기관에서 이루어지는 컴퓨터 실습 등과 같이 사용자 호스트의 외부망 접속 제한이 필요한 때에, 저비용으로 간단히 접속 제어 시스템을 구축하는 기법을 제안한다. 제안된 기법은 중 간자 공격 기법(Man In The Middle, MITM) 중 하나인 ARP Spoofing을 이용하여 LAN 클라이언트에서 출발한 패킷이 게이트웨이 바깥으로 포워딩되지 않도록 하는 방식으로 클라이언트의 외부망 접속을 차단한다. 따라서 클라이언트 호스트에 별도의 방화벽이나 Agent를 설치할 필요가 없기 때문에 간편하고 경제적인 시스템 구축이 가능하다.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2002년도 Molecular and Cellular Response to Toxic Substances
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• pp.153-153
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• 2002

Methylmercury (MeHg), one of the heavy metal compound, can cause severe damage to the central nervous system in humans. Many reports have contributed MeHg poisoning to contaminated foods and release into the environment. Despite many studies on the pathogenesis of MeHg-induced central neuropathy, no useful mechanism of toxicity has been established.(omitted)

• The Korean Journal of Physiology
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• 제18권2호
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• pp.171-180
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• 1984

The death of cattle from acute bracken poisoning has been recognized for many years. Acute bracken poisoning is characterized by mucoidal nasal and anal hemorrhage, severe anorexia. pyrexia, gastric ulcer and myocardial damage. In 1958 Evans first suggested that clinical picture of bracken poisoning was very much similar to that of radiation injuries such as aplastic anemia, leucopenia, thrombocytopenia and increased capillary fragility. Bracken has been clearly demonstrated to contain a carcinogen as well as thiaminase. However, the nature of carcinogen in bracken has not definetely elucidated. Also it was warned by several workers that bracken could be a causative factor for stomach cancer in Korean and Japanese. It appears that little is known on the e(feet of bracken on the function of cardiovascular system. Therefore the present study was designed to explore effects of ethanol extract of raw and toiled bracken (RBEE:BBEE) on blood pressure in cats. Also studied was the mechanism underlying changed in blood pressure of cats by bracken. The result obtained were as follows; 1) Mean arterial blood pressure was invariably decreased following administration of either RBEE or BBEE. Tn general depressor responses to RBEE persisted longer than that to BBEE. Generally, depressor responses were proportional to debases of RBEE and BBEE administered. 2) After administration of 60 mg/kg RBEB and BBEE, blood Pressure decreased by $62.1{\pm}1.7mmHg$ and $68.0{\pm}3.0mmHg$, respectively. No change was observed between depressor responses to RBEE and that to BBEE. 3) Depressor responses to BBEE and RBEE were not affected by vagotomy, propranolol and regitine. 4) In atropinized animal depressor responses to BBEE and RBEE were reduced by 30-40% showing part of depressor response was resulted from cholinergic effect of bracken.

• 생명과학회지
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• 제11권3호
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• pp.259-265
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• 2001

Mercury vapor inhalation-induced acute respiratory failure(ARF) has been reported to be fatal. This study was designed to observe the possible mechanism of inhaled mercury vapor poisoning in the respiratory system. Sixty percent of rats(12/20) exposed to mercury vapor were dead within 72 hours of exposure whereas all the rats(20/20) exposed to mercury vapor combined with dithiothreitol(DTT) vapor survived. The histological observation showed that ARF was a direct cause of the death induced by mercury vapor inhalation, which was significantly circumvented by DTT vapor. Cyclic AMP mediated chloride secretion was inhibited by luminal side but not serosal side sulfhydryl blocking agents (Hf$^{2+}$ $\rho$-chloromercuribenzoic acid or $\rho$-chloromercuriphenyl sulfonic acid) in a dose-dependent manner in a primary cultured rat airway monolayer. The inhibitory component of cAMP induced chloride secretion was completely restored by luminal side DTT(0.5mM). these results suggest that the oxidized form(Hg$^{2+}$) of mercury vapor(Hg0) contribute to ARF and subsequent death. The finding is important as it can provide important information regarding emergency manipulation of ARF patients suffering from by mercury vapor poisoning.ing.

• 한국발생생물학회지:발생과생식
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• 제1권2호
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• pp.125-132
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• 1997

To investigate the cadmium (Cd) toxicity on the testis, male rats were treated with 1, 2, 4 and 8 mg/kg of Cd by IP. According to histochemical studies, Cd-treated testis tissue showed death of spermatozoa, death of Sertoli cells, death of all the spermatogenic cells, and finally disappearance of basal lamina of seminiferous tubules with increasing doses, and showed decreased ground substances and Leydig cells, increased inflammatory cells and fibroblasts, and fibroblasts, and finally disappearance of ground substances and all the cells except fibroblasts within interstitial tissues with increasing doses. According to biochemical studies, two kinds of proteins, 25 and 45 kDa, were dramatically disappeared from the total protein of rat testis treated with Cd comparing to normal testis. The result of electrophoresis of total protein suggests that actin (45 kDa), presumed on its mmolecular weight and amount, in the testis-cells is the primary target of Cd poisoning. Although its exact mechanism is not clear, the disappearance of two proteins when testis is exposed to Cd should give some clues to understnad the mechanism of necrosis of testis tissue crumbling by heavy metal pollutant such as Cd.

• 융합보안논문지
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• 제22권3호
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• pp.25-32
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• 2022

최근 이미지 인식 및 탐지 분야에 딥러닝 기반의 기술이 도입되면서 영상 처리 산업이 활성화되고 있다. 딥러닝 기술의 발전과 함께 적대적 공격에 대한 학습 모델 취약점이 계속해서 보고되고 있지만, 학습 시점에 악의적인 데이터를 주입하는 포이즈닝 공격의 대응 방안에 대한 연구가 미흡한 실정이다. 종래 포이즈닝 공격의 대응 방안은 매번 학습 데이터를 검사하여 별도의 탐지 및 제거 작업을 수행해야 한다는 한계가 있었다. 따라서, 본 논문에서는 포이즌 데이터에 대해 별도의 탐지 및 제거과정 없이 학습 데이터와 추론 데이터에 약간의 변형을 가함으로써 공격 성공률을 저하시키는 기법을 제안한다. 선행연구에서 제안된 클린 라벨 포이즌 공격인 원샷킬 포이즌 공격을 공격 모델로 활용하였고, 공격자의 공격 전략에 따라 일반 공격자와 지능형 공격자로 나누어 공격 성능을 확인하였다. 실험 결과에 따르면 제안하는 방어 메커니즘을 적용하면 종래 방법 대비 최대 65%의 공격 성공률을 저하시킬 수 있었다.

• 대한임상독성학회지
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• 제4권2호
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• pp.158-160
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• 2006

Acute methemoglobinemia is induced by various causes, especially ingestion of oxidizing agents such as phenazopyridine, dapsone, and nitrite. Indoxacarb is an oxadiazine insecticide with high insecticidal activity and low mammalian toxicity. It is known to block voltage-gated Na+ channels in insects and mammals, but the mechanism is not yet well understood. We describe a case of a 41-year-old woman with methemoglobinemia that developed following Indoxacarb ingestion, which improved after intravenous injection of methylene blue. This is the first known such case. If signs and symptoms of methemoglobinemia occur after Indoxacarb ingestion, antidotal therapy with methylene blue should be considered as a necessary treatment.

• Investigative Magnetic Resonance Imaging
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• 제18권4호
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• pp.352-356
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• 2014

본 증례의 51세 남자 환자는 글루포시네이트 암모니움을 과다 섭취한 후에 전향적 기억상실증이 발생하였다. 뇌 자기공명영상에서 양측 해마와 해마옆이랑, 오른쪽 후두엽에서 고신호강도 병변을 관찰할 수 있었다. 급성 글루포시네이트 암모니움 중독이 해마에 병변을 만드는 기전과, 양측성 해마에서 생길 수 있는 질환들의 감별진단에 대하여 논하고자 한다.

• Toxicological Research
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• 제4권2호
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• pp.85-94
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• 1988

In order to elucidate the mechanism of toxic action of a pisonous mushroom, Amanita pantherina, biochemical effects of the mushroom extracts on mice were studied. A hotwater extract of Amanita pantherina injected intraperitoneally into male ICR mice evoked signs similar to those observed clinically upon acute poisoning by the mushroom and also changed the levels of component enzyme activities in blood, liver and urine. The serum cholinesterase activity was decreased significantly during 1-3 h after injection.