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        검색결과 360

        161.
        2012.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        우리나라에서 건축물 내장재의 화재안전성능은 국토해양부 고시 제2011-39호에 의한 평가방법에 의해 불연성시험(KS F ISO 1182), 열방출률시험(KS F ISO 5660) 및 가스유해성시험(KSF 2271)을 실시하여 그 결과로서 분류하도록 되어 있다. 그 중 연기 및 연소독성가스에 대한 시험인 가스 유해성 시험은, 건축재료 및 내장재의 연소시 발생하는 가스의 유해성을 마우스의 평균 행동정지시간으로 측정하는 방법으로 사용하여 왔다. 이 중 연소 독성가스 4종(HCl, HF, HCN, SO2) 흡입독성시험방법의 확립을 위하여 ICR계 mouse와 전신흡입노출장치를 이용하여, 독성가스 노출 및 병리검사를 수행하였다. 그 결과 호흡기관지와 가까운 폐포에서 대식세포(Macrophage)의 침윤을 유발하는 것으로 나타났고, 4종의 물질에 대한 조직의 병리검사로 전체적으로 충혈과 울혈은 확인되었다. 조직 중 폐와 신장에서 조직손상이 심하였고, 물질로는 HCN이 가장 많은 병리소견을 보였다.
        4,300원
        162.
        2012.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
         ,  , Effect of a new crop protectant ‘Bt-Plus’ on natural enemies was analyzed in this study. Tested natural enemies included two parasitic species of Aphidius colemani and Eretmocerus eremicus, and four predatory species of Harmonia axyridis, Orius laevigatus, Amblyseius swirskii, and Phytoseiulus persimilis. ‘Bt-Plus’ was formulated by combination of three entomopathogenic bacteria (Xenorhabdus nematophila (Xn), Photorhabdus temperata subsp. temperata (Ptt), Bacillus thuringiensis (Bt)) and bacterial metabolite (BM). All three types of ‘Bt-Plus’ showed significantly higher toxicities against fourth instar Plutella xylostella larvae than Bt single treatment. Two types of bacterial mixtures (‘Xn+Bt’ and ‘Ptt+Bt’) showed little toxicity to all natural enemies in both contact and oral feeding assays. However, ‘BM+Bt’ showed significant toxicities especially to two predatory mites of A. swirskii and P. persimilis. The acaricidal effects of different bacterial metabolites were evaluated against two spotted spider mite, Tetranychus urticae. All six BM chemicals showed significant acaricidal effects. The BM mixture used to prepare ‘Bt-Plus’ showed a high acaricidal activity with a median lethal concentration at 218.7 ppm (95% confidence interval: 163.2 - 262.3). These toxic effects of bacterial metabolites were also proved by cytotoxicity test against Sf9 cells. Especially, benzylideneacetone, which was used as a main ingredient of ‘BM+Bt’, showed high cytotoxicity at its low micromolar concentration.
        4,300원
        163.
        2012.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was carried out to observe the impacts of a mouse's inhalation of toxic gas SO2 generated from combustion on its organs by different concentrations. As for research methods: First, after concentrations of SO2 generation from combustion had been set to three: low (10.4 ppm), middle (24.9 ppm) and high (122 ppm) through Gas Toxicity Testing Method (KS F 2271) and SO2 combustion gas was exposed to eight mice in each concentration. Five mice that were able to move based on LD50, a criterion, which sets the down time of a mouse's average behaviors to over 9 minutes, were randomly selected in each concentration, and they were set up as the subjects of the study on toxicity bio-markers. Second, tissues were taken from heart, liver, lungs, spleen and the thymus gland of the mice selected in each concentration and a pathological examination of them was carried out. As a result, microvascular congestion appeared in the heart, and cell necrosis, cortex congestion and tubule medulla congestion, etc. in each concentration were observed in addition to vascular congestion in liver, lungs, spleen and the thymus gland. Also, it was found that the higher the concentrations of SO2 exposure is, the greater, the changes in the organs get. Through this study, SO2 of various toxic gases generated from fire turned out to affect the tissues of each organ of a mouse, it is expected that the toxic gases may greatly affect human body in case of actual fire, and this study is evaluated as having a significance as a basic data on inhalation toxicity assessment of toxic substances generated in combustion.
        4,000원
        164.
        2011.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This test was performed to evaluate the acute oral toxicity and skin irritation of Lamia-Kill®, disinfectant,containing 20% benzalkonium chloride and 10% citric acid. In acute oral toxicity, Lamia-Kill® was orally administered at dose levels of 2,000, 1,000, 500, 250 and 0 mg/kg body weight. After single oral administration to both sexes of SD rats, the rats were observed for 14 days. In primary skin irritation test, New Zealand white rabbits were dermally treated with Lamia-Kill® for 24 hr and observed for 3 days. All rats treated with Lamia-Kill® were induced no toxic signs in mortalities, clinical findings, body weights and gross findings. Also, the disinfectant did not induce any adverse reactions such as erythema and edema on intact skin sites for the most part rabbits, but on abraded skin sites, some rabbits showed very slight erythema on 24 hr after topical application. With the results of this study,Lamia-Kill® have no effect on acute toxicity and side effect in SD rats and was classified as a practically non-irritating material based on the score 0.50 of primary irritation index.
        4,000원
        165.
        2011.12 구독 인증기관 무료, 개인회원 유료
        Cellular uptake of nanoparticles for stem cell labeling and tracking is a critical technique for biomedical therapeutic applications. However, current techniques suffer from low intracellular labeling efficiency and cytotoxic effects, which has led to great interest in the development of a new labeling strategy. Using silica-coated nanoparticles conjugated with rhodamine B isothiocyanate (RITC) (SR), we tested the cellular uptake efficiency, biocompatibility, proliferation or differentiation ability with murine bone marrow derived hematopoietic stem/progenitor cells. The bone marrow hematopoietic cells showed efficient uptake with SR with dose or time dependent manner and also provided a higher uptake on hematopoietic stem/progenitor cells. Biocompatibility tests revealed that the SR had no deleterious effects on cell cytotoxicity, proliferation, or multi-differentiation capacities in vitro and in vivo. SR nanoparticles are advantageous over traditional labeling techniques as they possess a high level of cellular internalization without limiting the biofunctionality of the cells. Therefore, SR provides a useful alternative for gene or drug delivery into hematopoietic stem/progenitor cells for basic research and clinical applications.
        4,000원
        166.
        2011.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        BPA, a diphenyl compound containing groups, that make it structurally similar to synthetic estrogen and is considered as one of the major endocrine disruptors. Silymarin has extensively been used to prevent and/or alleviate some human disease, especially for the treatment of adverse liver conditions. It has an antioxidative efficacy and cancer preventive efficacy. Therefore, we examined the hypothesis that silymarin can inhibit BPA-induced toxicity in boar sperm duing in vitro storage. Sperm characteristics (motility, viability, membrane integrity and mitochondrion activity) in semen exposed to BPA (10~200 uM) were sharply lowered, while it increase in a dose and time dependent manner due to silymarin addition (50~200 uM) into semen extender in the presence of BPA (100 uM). All of the evaluated characteristics were gradually improved in the groups that were treated with silymarin (50~200 uM) in the presence of BPA (100 uM) in comparison to BPA 100 uM alone group, irrespective of incubation periods (3 and 6 h). These results demonstrate that silymarin can ameliorate the toxicity of BPA on boar sperm characteristics during in vitro storage, suggesting that silymarin indirectly act as an antioxidant.
        4,000원
        167.
        2011.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 칼륨의 독성에 따른 배추의 생육과 생리적 특성 그리고 형태적 변화를 관찰하기 위하여 수행하였다. 100mM의 칼륨 농도 처리구까지 전체적인 생육이 증가한 반면, 600mM 처리구에서 생육이 가장 저조하였다. 칼륨 처리 농도가 높을수록 N, P, K, 함량은 증가하였지만 Ca, Mg, Na 함량은 감소하는 경향을 보였으며 미량원소, Fe, Mn, Zn의 경우 100mM의 처리구에서 가장 높은 함량을 나타내었다. 생체중당 Chl a, b와 carotenoid 함량은 600mM에서 가장 많이 증가하였으나 증가한 엽록소 함량에 비해 광합성효율(Fv/Fm)은 처리구간에 차이가 없었고 CO2 동화율은 오히려 감소하였다. 이는 칼륨 과다에 의한 삼투스트레스의 결과로 기공의 퇴화와 CO2 동화능력과 밀접한 관계가 있는 것을 형태학적 관찰로 확인되었다. Total free amino acid의 경우 100mM 처리구까지 칼륨 처리 농도가 증가함에 따라 증가한 반면 600mM에서 급격히 감소하였다. 따라서 본 실험에서의 배추는100mM의 칼륨 농도까지는 긍정적인 효과가 있는 것으로 판단되었다.
        4,000원
        168.
        2011.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The lowest amount of heavy metals was found outside the city (25 km away), the highest amount was found near the thermoelectric power plant, and the average amount was discovered in the central part of the city. The presence of heavy metals in soil sample
        3,000원
        169.
        2011.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        넙치 치어에 대한 나프탈렌의 급성독성을 조사하기 위하여 대조구(0μg/L), 1000, 1800, 3200, 5600, 10000μg/L의 6개의 나프탈렌 농도구를 설정하여 24시간 동안 노출실험을 실시하고 혈액학적 성상을 분석하였다. 넙치 치어에 대한 나프탈렌의 24h-LC50은 3600μg/L를 나타냈다. 넙치 치어의 핼액학적 반응에서 헤마토크리트값은 5600, 10000μg/L의 농도구에서 대조구와 비교하여 유의하게 증가하였고, 글루코스는 10000μg/L의 농도 구에서 유의하게 증가 하였다(P〈0.05). 삼투질 농도는 3200, 5600, 10000μg/L의 농도구에서 유의하게 증가하였다. 반면, 이온분석 결과 [Na+], [K+]은 5600 및 10000μg/L 나프탈렌 농도구에서 유의하게 증가하였으나 [Cl-]는 큰 차이를 보이지 않았다.
        4,000원
        170.
        2011.05 구독 인증기관·개인회원 무료
        The rice weevil, Sitophilus oryzae, is one of the most common storage pests worldwide of grocery shops, flour mills and warehouses. This study investigated to assess the contact and fumigant toxicities of Juglnas regia and its active component against the S. oryzae adults. Using the two different bioassays against S. oryzae adults, the methanol extract of J. regia at 20 mg had the moderate (++) activity and weak (+) activity using direct contact and fumigant method, respectively. The methanol extract was partitioned with hexane, chloroform, ethyl acetate, butanol and water fraction. Ethyl acetate fraction obtained from the methanol extract showed strong (+++) and weak (+) activity at 10 mg using direct contact and fumigant method, respectively. Ethyl acetate fraction was purified by silica gel column chromatography and high performance liquid chromatography (prep-HPLC). The structure of active component was analyzed by EI-MS, 1H-NMR and 13C-NMR spectra, and was identified as C-21233. Purified C-21233 from ethyl acetate fraction had strong (+++) and moderate (++) activity using direct contact and fumigant method against S. oryzae adults. These results indicate that active component in J. reiga derived materials could be potential candidates as a contact and fumigant for managing S. oryzae adults. Further studies should be performed to the structure activity relationship of C-21233 and compared with its derivatives.
        171.
        2011.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        For the application of nano-sized material in various fields, the evaluation of nano-sized material toxicity is important. In the present study, various concentrations of 200 nm-sized silicon dioxide nanoparticle suspension were intraperitonially injected into mice to identify the toxicity of silicon dioxide nanoparticle in vivo. In the hematological analysis of group II treated with silicon dioxide nanoparticle 100 mg/kg body weight, lymphocytes and monocytes were significantly different compared to the control group. In group III treated with silicon dioxide nanoparticle 200 mg/kg body weight, lymphocytes, monocytes and hemoglobin were significantly different compared to the control group. In blood biochemical analysis of group III, the concentration of AST, ALT, BUN, and creatinine were significantly different compared to the control group. Histopathologic examination of the kidney indicated a mild injury only in mice received 200 mg/kg silicon dioxide nanoparticle. According to the results of the present study, the significant differences in the hematological and blood biochemical analyses and abnormal histopathological findings in the mouse kidney may have been related to exposure to silicon dioxide nanoparticle.
        4,000원
        172.
        2011.03 구독 인증기관 무료, 개인회원 유료
        Neurotoxicity and oxidative injury induced by glutamate cause neuronal degeneration related to various central nervous system diseases. Resveratrol, a polyphenolic compound, is known to have antioxidative and anti-inflammatory effects. The aim of this study was to investigate the question of whether resveratrol has a neuroprotective effect against glutamate-induced toxicity in cultured cortical neurons. Following exposure to glutamate for 15 min, cortical neurons originating from ICR mouse fetuses on embryonic days 15-16 were then treated with resveratrol for 24 h in the post-treatment paradigm. Glutamate induced a significant reduction in cell viability; however, resveratrol induced a significant increase in cell viability. Glutamate induced generation of ROS and apoptotic neuronal death; however, these were decreased by exposure to resveratrol. mRNA expression in antioxidant enzymes, cytoplasmic glutathione peroxidase, copper/zinc superoxide dismutase (SOD), and manganese SOD, and anti-apoptotic regulator Bcl-xL were decreased by exposure to glutamate, however, exposure to resveratrol resulted in a significant increase in their mRNA levels. In addition, mRNA expression of pro-inflammatory cytokines, interleukin-1β and tumor necosis factor-α, was increased by glutamate insult, but significantly reduced by resveratrol. These findings indicate that resveratrol is neuroprotective against glutamate-induced toxicity, suggesting a useful therapeutic application in treatment of neurodegenerative disorders.
        4,200원
        173.
        2010.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        해양구조물 수중부의 해양생물 부착을 방지하는 효과적인 방법으로 방오도료를 사용하고 있다. 트리부틸틴(Tributyltin, TBT) 화합물은 우수한 방오성능을 가져 지금까지 광범위하게 사용해 되어 왔으나, 유해물질 사용금지에 따라 새로운 기술을 적용한 방오도료 개발이 진행되고 있다. 신규 방오도료는 낮은 독성을 가지면서도 우수한 방오성능을 가져야 한다. 본 논문에서는 상용 TBT-free 방오도료 3종(아산화동 함유 자기마모형 도료(Cu SPC AF), 아산화동을 함유하지 않는 자기마모형 도료(Cu-Free SPC AF), Foul-release 실리콘 도료(Foul release AF)의 용출수가 가지는 환경영향성을 조피볼락과 알테미아를 사용하여 평가하였다. 용출수에 대한 급성독성을 조사한 결과 방오도료 용출수의 농도와 생물종의 생존율은 반비례하는 경향을 나타내었으며, 자가마모형 도료가 Foul-release 실리콘 도료보다 상대적으로 높은 급성독성을 가지는 것을 확인할 수 있었다.
        4,000원
        174.
        2010.12 구독 인증기관 무료, 개인회원 유료
        For application of nano-sized material in various fields, toxicity evaluation of nano-sized material is important. In the current study, a suspension of 50 nm-sized zinc oxide (ZnO) nanoparticles at a dose of 1 g/kg body weight was injected intraperitonially into mice in order to identify the toxicity of ZnO nanoparticles. After 24 h, the blood and liver were taken and analyzed. According to the results of hematological analysis, white blood cell (p<0.001), mean corpuscular hemoglobin (p<0.001), and mean corpuscular hemoglobin concentration (p<0.05) in the ZnO nanoparticle treated group showed a significant decrease, compared to the control group. In serum biochemistry analysis, alanine aminotransferase (p<0.001) and aspartate amino-transferase (p<0.05) also induced a significant increase in the ZnO nanoparticle treated group, compared with the control group. In the histopathological examination, liver in mice treated with ZnO nanoparticles showed edema and degeneration in hepatocytes. Therefore, it is concluded that the liver is the target organ for 50 nm ZnO intraperitoneal exposure. In the future, greater attention should be paid to the potential toxicity induced by various routes and doses of ZnO nanoparticles.
        4,000원
        175.
        2010.11 구독 인증기관 무료, 개인회원 유료
        해양생태 독성시험법의 중요성이 인식되면서 새로운 시험법의 개발과 더불어 유용수산생물을 이용하고자 하는 연구가 활발하게 진행되고 있으나, 대부분의 시험법은 유해물질에 대한 급성독성을 평가하고 있다. 해양생태계 내에서 오랫동안 아치사 농도로써 생물에게 영향을 미치는 유해물질을 평가하기 위한, 만성독성 평가기법은 그 수가 대단히 한정되어 있다. 유용수산생물 자원인 미역(U ndar ia pinnatifida )은 생산자로서 해양생태계 내에서 중요한 위 치를 차지하고 있을 뿐만 아니라, 유주자 방출, 발아, 수정 및 아포체 성장의 초기생활사 동안 실내배양이 가능하다. 실내 배양기간 동안 아포체 성장을 이용한 만성적 독성영향을 파악할 수 있어, 향후 해양생태 독성시험과 환경변화 등에 의해 발생하는 갯녹음 원인 구명에도 적절하게 이용될 수 있을 것으로 판단된다. 성숙한 U . pinnatifida의 포자 엽으로부터 방출된 유주자를 6개 중금속(Cd, Cu, Zn, Pb, Cr, As)에 노출시켜 21일간 배양한 후에 아포체 성장률을 측정하였고, 이들 결과를 바탕으로 무영향농도(NOEC), 최소영향농도(LOEC)를 나타내는 독성평가를 실시하였다. 중 금속에 노출된 U . pinnatifida의 아포체 성장률은 중금속 농도가 증가할수록 급격히 감소하는 농도 의존성을 나타냈 다. 중금속이 아포체 성장에 미치는 영향의 정도를 살펴보면, 대부분이 0.1ppb 미만의 낮은 농도에서 NOEC가 관찰 되었고 LOEC의 경우도 Cd, Cu 및 Pb는 0.1ppb에서, Zn, Cr 및 As는 1ppb 정도의 매우 낮은 농도를 나타내는 것을 알 수 있었다.
        3,000원
        176.
        2010.10 구독 인증기관·개인회원 무료
        In the previous study, the plant essential oils such as clove bud , thyme white and garlic oils gave potent toxicity with the range of 1.5 to 4.5×10-3 ul cm-3 of LC50 values against Bemisia tabaci. Based on the bio-assay results, three plant essential oils(clove bud, thyme white and garlic) were applied to 30% emulsion type. The 100, 200 and 400 fold dilution of these emulsions was showed mild toxicity under port scale treatment against Q biotype. At each fold dilution, clove bud showed 44, 26 and 14%, and thyme white produced 44, 39 and 27%, respectively. Of garlic emulsion, its toxicity was evaluated with 27, 26 and 11%, respectively. But, in case of clove bud and thyme white mixture, their toxicity was more good under the mixture than under the single treatment. Mixture with clove bud 200 fold dilution adding to thyme white 200 fold dilution showed potent activity with 86% mortality. And also 200 adding to 400, and 400 to 400 exhibited 61%, 76%, respectively. These essential oil mixtures showed similar strong toxicity against B biotype under port scale test. In particular, the mixture with clove bud 200 fold dilution adding to thyme white 200 fold dilution showed the highest synergistic effect. Toxicity to plants, except the 100 fold dilution of these emulsions was not observed.
        177.
        2010.10 구독 인증기관·개인회원 무료
        The oral toxicities of symbiotic bacteria Photorhabdus temperata ssp temperata (Ptt), mutually associated with entomopathogenic nematode Heterorhabditis megidis, and P. luminescens ssp. laumondii (TT01) with H. bacteriophora, were demonstrated to adults of the sweetpotato whitefly Bemisia tabaci. Sucrose solution (25%) containing bacteria-free supernatant of culture media of symbiotic bacteria was ingested into adult whiteflies within the glass tube. Whitefly mortalities were shown similar patterns against two bacterial media. Mortalities were significantly increased to 60-64% at 36 hours and almost 100% at 60 hours after treatments. In addition, We demonstrated the effect of oral ingestion of symbiont culture media on the gene expression of B. tabaci. Several genes fluctuated those expression levels. Our results suggest that oral ingestion of symbiont culture media of entomopathogenic nematodes significantly changed metabolic rates and highly lethal to whiteflies. The use of symbiotic bacteria of entomopathogenic nematodes provides a great potential as an alternative genetic resource of Bacillus thuringiensis, a major resource of microbial insecticide.
        178.
        2010.09 구독 인증기관 무료, 개인회원 유료
        This study was conducted in order to investigate repeated-dose toxicities of Magnolia ovobata ethanol extract (MEE). MEE was administered orally to male and female Sprague Dawley rats at dose levels of 0, 500, 1,000, or 2,000 mg/kg for four weeks. Repeated administration of MEE did not induce abnormalities in general signs, body weight gain, feed and water consumption, necropsy findings, or organ weights. In addition, no abnormality was observed in hematological analyses; red blood cells and their indices, white blood cells, platelets, and coagulation times. In male rats, BUN and creatinine showed an increase at doses of 2,000 mg/kg and 500-1,000 mg/kg, respectively, while in female rats, lactate dehydrogenase and creatine phosphokinase showed a decrease at 2,000 mg/kg, the upper-limit dose of repeated-dose toxicity studies. However, there were no dose-dependent increases or gender-relationship. In addition, other parameters of the hepatic and muscular toxicities as well as energy and lipid metabolism were not affected. In microscopic examination, no considerable pathological findings were observed. The results indicate the safety of oral administration of MEE to the upper-limit dose.
        4,000원
        179.
        2010.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 8주령 Sprague-Dawley계통의 암컷 랫드에서 제독유황을 반복경구투여 독성평가를 하기위해 시행하였다. 랫드에 처치한 물질은 사료섭취량의 0.2%, 1%, 5% 제독유황과 사료섭취량의 1% 유황으로 13주 경구투여를 하였다. 제독유황의 안전성을 확인하기 위해 다음과 같은 관찰 및 검사를 하였다. 검사항목으로는 체중과 사료 섭취를 측정하였고 임상증상, 안과학적 검사, 혈액학적 검사, 혈청 생화학적 검사를 관찰하였다. 또한 랫드에 간과 신장에서 의 병리조직학적 변화를 관찰하였다. 그 결과 체중, 사료섭 취량, 혈액학적 및 병리조직검사 소견에서 대조군과 제독 유황 그룹 간의 유의적인 차이가 보이지 않았다. 혈청생화 학적 검사소견에서는 0.2% 및 1% 투여군에서는 대조군과 비교시 용량의존적으로 유의적인 차이를 보이는 항목은 보이지 않았으나, 고용량군에서는 glucose 감소에 의한 저칼 륨혈증, 인슐린 과잉분비의 독성을 의심할 수 있었으며, 또 한 ALT와 ALP의 증가는 간 독성이나 간암, 황달의 유발이 의심되었다. 한편, 병리조직학적인 검사에서는 시험 전체군에서 대조군과 비교시 유의할만한 병리조직이상이 관 찰되지 않았다. 따라서 본 연구에서는 사료섭취량 1%의 제독유황까지 투여는 랫드에서 독성을 나타내지 않는 것으로 사료된다.
        4,000원
        180.
        2010.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Toxicity of seven environment friendly agricultural materials (EFAM), which have been used in the domestic market were evaluated on honeybee (Apis mellifera) and asian multicolored ladybird beetle (Harmonia axyridis). Three EFAMs made from plant extract agents (Wangjoongwang Eco, Bogum Eco and Bestop Eco) and four EFAMs made from microbial utilizing agents (Worldstar Eco, Goodmorning, Bluechip and Cameleon) were investigated as EFAMs. In evaluation of toxicity on honeybee, the RT25 values of 3 EFAMs made from plant extract agents ranged from 1 to 3 days. Therefore, honeybee should be released 1-3 days after application of these EFAMs. Meanwhile, the four agricultural materials made from microbial utilizing agents did not show any mortality against honeybee. In evaluating the toxicity to adult and larva ladybird beetles, all seven EFAMs made from plant extract agents and microbial utilizing agents to show any mortality.
        4,000원