• Title/Summary/Keyword: 선택독성

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Age-related Susceptibility of Spodoptera litura Larvae to Some Insecticides (담배거세미나방 유충의 영기별 약제 감수성)

  • 조점래;송원례;황선영;김홍선;이정운
    • Korean journal of applied entomology
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    • v.35 no.3
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    • pp.249-253
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    • 1996
  • In the laboratory study, the toxicities of chlorpyrifos-methyl, chlorpyrifos, etofenprox, etofenprox+PAF' and deltamethrin for different larval instars of S. litura decreased significantly as larvae aged. LCso values for chlorpyrifos- methyl and chlorpyrifos increased significantly from 3rd instar larvae, while those for etofenprox+PAP and deltamethrin-increased from 2nd instar larvae. In pot study, no significant differences in control efficacy were observed among each treated plots and over 90% control efficacy at 5 d after treatment was obtained in all of the treated plots, except treatment with deltamethrin. Therefore four insecticides excluding deltamethrin will be effective for controlling S. litura. However, it will be probably important to select appropriate insecticides and decide a proper time of treatment because the developmental stage is a significant factor in deciding insecticide efficacy because various developmental stages of the tobacco cutworm inhibit in fields.

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A Study on the Reactivity, Performance of 4HBA Modified High Solid Acrylic Polyurethane Paint (4HBA 변성 하이솔리드 아크릴 우레탄 도료의 반응성 및 물성 연구)

  • Seo, Seok-Hwan;Suh, Cha-Soo;Park, Jin-Hwan
    • Applied Chemistry for Engineering
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    • v.20 no.1
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    • pp.52-61
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    • 2009
  • In this study, TAPEH (t-amyl peroxy 2-ethyl hexanoate) was selected for the reaction initiator which is a core factor for developing acrylic polyol binder. Tone M100 (caprolactone acrylate), 4HBA (4-hydroxy butyl acrylate), and 2HEMA (2-hydroxy ethyl methacrylate) were used for hydroxy-monomers. To check the applicability of raw materials mentioned above into the binders of 2 components acrylic polyurethane paint and reduce the VOC, the reactivity and film performance by different kinds of aliphatic polyisocyanate hardeners which are already generalized were reviewed. As the Tin-based catalyst has been regulated, the comparison test of reactivity and performance between the conventional catalyst and non-toxic metal catalyst recommended as the alternative was conducted as well. As a result, we were able to obtain the basic data which are necessary for applying 2 components high solid polyurethane paint and also reached a conclusion that it can be applied for developing new paints in terms of high performance, workability and environmental care.

Issues in 2-year Long-term in vivo Carcinogenicity Assay (2년 장기 발암성 검색법의 이슈)

  • Son, Woo-Chan;Kim, Bae-Hwan;Jang, Dong-Deuk;Han, Beom-Seok;Kim, Jong-Choon;Lee, Je-Bong;Shin, Jin-Sup;Kim, Hyoung-Chin
    • The Korean Journal of Pesticide Science
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    • v.8 no.4
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    • pp.239-254
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    • 2004
  • It has been debating about conducting and interpretating of 2-year rodent carcinogenicity bioassay. Although some criticisms arising in usefulness, it has been still known that long-term carcinogenicity studies using rodents would be the only assay system to predict any possible human risks, which would not be replaced. Both regulatory agencies and academies have developed some assay models, however, there have been controversy whether those study designs and interpretations are based on sound scientific rationale and validated data. Such kinds of issues including choice of species/strain, dose level selection, duration of study, number of animals per group, historical control data, monitoring parameters, terminal investigations, peer review, statistics, alternative assay models, interpretation of neoplastic lesions, and risk assessments, were reviewed.

Suppression of Matrix Metalloproteinase-9 Expression of Flavonoids from Metasequoia glyptostroboides (낙우송(Metasequoia glyptostroboides)으로부터 분리한 flavonoid의 금속단백분해효소-9 발현 억제 활성)

  • Yang Jae-Young;Lee Ho-Jae;Kho Yung-Hee;Kwon Byoung-Mok;Chun Hyo Kon
    • Journal of Life Science
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    • v.15 no.2 s.69
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    • pp.231-235
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    • 2005
  • Matrix metalloproteinases (MMPs) are a family of structurally and functionally related zinc-dependent enzymes responsible for proteolytic degradation of extracellular matrix components such as base membrane or interstitial stroma. MMPs play an important role in a variety of physiological and pathological tissue remodeling processes, including wound healing, embryo implantation, tumor invasion and metastasis. Since MMP-9 (gelatinase B) has unique ability to cleave type IV collagen, gene expression of MMP-9 has been focused on as a pharmacological target. Flavonoids are a class of compounds that are widely spread in plants. In the coures of screening for the suppressors of MMP-9 gene expression from natural products, Metasequoia glyptostroboides was selected. Six flavonoids, sciadopitysin, isoginkgetin, bilobetin, 2,3-dihydrohinokiflavone, luteolin and apigenin were purified as suppressors of MMP-9 gene expression from M. glyptostroboides. The suppressing activity of the isolated flavinoids on the MMP-9 gene expression was measured by gelatin zymography and Nothern blot analysis.

Study on the Response of Weed Species to Paraquat Absorbed Through Root System (뿌리를 통하여 흡수된 Paraquat에 대한 잡초종(雜草種)들의 반응(反應))

  • Kang, B.H.;Shim, S.I.;Lee, S.G.
    • Korean Journal of Weed Science
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    • v.15 no.1
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    • pp.1-12
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    • 1995
  • These researches have been conducted to obtain the basic information of the effects of paraquat on plant species and to screen the plant species showing specific responses to paraquat. Paraquat resistance related to ecotype and overwintering capacity. Perennial and biennial species showed higher resistance than annual species. In a family, most species showed higher resistance were overwintering species. Lamiaceae, Brassicaceae, and Caryophyllaceae were tolerant to paraquat, whereas Poaceae and Asteraceae were sensitive. Especially Mosla dianthera of Lamiaceae, Hemistepta lyrata and Aster pilosus of Asteraceae, and Paspalum thunbergii of Poaceae showed higher tolerance than others. The response patterns of plant species on germination stage were different to those on vegetative stage. Germination of Amarathus lividus, Arabis glabra, and Bidens frondosa was not inhibited by paraquat. But their seedling growth were highly inhibited.

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무당개구리에서 내분비계장애물질에 의한 발생독성 평가

  • Gang, Han-Seung;Gye, Myeong-Chan;Kim, Mun-Gyu
    • Proceedings of the Korea Society of Environmental Biology Conference
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    • 2005.12a
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    • pp.22-35
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    • 2005
  • 내분비계 장애물질 (Endocrine Disruptors: EDs)이란 ‘내분비 기능에 변화를 일으켜, 생체 또는 그 자손의 건강에 위해한 영향을 미치는 외인성 물질’로서 세계야생생물보호기금 (World Wildife Fund: WWF)의 목록에는 67 여종, 일본 후생성에서는 142 여종의 물질을 내분비계 장애물질로 분류하고 있다. 이렇게 분류된 내분비계장애물질 가운데에는 많은 종류의 농약이 포함되어 있으며, 이들이 자연상태계에 미치는 영향에 대한 많은 보고가 있다. 양서류는 먹이연쇄의 중위포식자로 내분비계 장애물질의 순환 및 생채축적 회로에서 중요한 위치를 갖는다. 또한 농경지나 계류 등에 서식하며 산란하는 습성이 있다. 이러한 서식지는 농약 등에 노출받기 쉬우므로 환경오염평가 대상동물로 중요하다. 본 연구에서는 국내에서 사용되고 있는 제초제, 살충제 등이 양서류 발생에 미치는 영향을 평가하고, 이들 물질에 의한 노출을 평가할 수 있는 biomarker 유전자를 발굴하고자 하였다. 우리나라 전역에 많이 분포하는 무당개구리(Bombina orientalis)의 초기 배아발생 과정에서 이들 농약을 처리하였을 때, 물질의 종류에 따라 정도의 차이는 있으나 농도 의존적으로 배아 및 올챙이의 치사율이 높게 나타났다. 또한 농약은 배아 및 올챙이의 기형을 유발하였다. 기형의 종류는 농약에 따라 서로 상이한 형태로도 나타났으나, 특히 몸통휨 또는 꼬리휨등의 척추골 기형이 많이 나타났다. 환경 위해성 평가 biomarker 유전자로서 골격계 형성에 관여하는 Sox9 유전자를 선택하였다. 무당개구리에서 처음으로 Sox9 유전자를 동정하였으며, 농약을 처리한 실험군에서의 Sox9 유전자의 발현 양상은 대조군에 비하여 높게 나타났다. 본 연구결과 생태계에서 내분비계 장애물질의 위해성 평가를 위해 양서류 초기배아의 치사 및 기형의 정도를 관찰하는 방법이 유효할 것으로 사료된다. 또한 야생동물의 biomarker 유전자를 발굴과 이를 이용한 위해성 평가는 더욱 정밀한 평가법으로 유용할 것이다.

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Biosorption Model and Factors for Removing Lead to Aureobasdium pullulans being Imperfect Fungus (불완전 균류 Aureobasdium pullulans으로 납을 제거하기 위한 인자들과 흡착모델)

  • Suh, Jung-Ho;Suh, Myung-Gyo;Chung, Kyung-Tae;Lee, Yong-Hee
    • Journal of Life Science
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    • v.16 no.6
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    • pp.877-883
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    • 2006
  • An alternative method to remove and recover heavy metals is biosorption based on metal-sequestering properties of natural or biological origin. In this study, the effects of factors such as temperature, pH, initial concentration of lead, and initial amount of biomass on biosorption of lead using Aureobasdium pullulans were investigated. A. pullulans has an excellent selectivity to remove lead than other heavy metals such as cadmium, chromium, nickel in pure and mixed solution. The optimum temperature of biosorption with A. pullulans was $40^{\circ}C$ and the amount of removal increased at high pH. The higher initial lead concentration or the lower cell dry weight, the higher amount of lead was adsorbed. The adsorption isotherm of lead was accorded with Freundlich model. The adsorption capacity and initial adsorption rate of living A. pullulans were about twice higher than that of dead one.

의류상품 소비자의 판매촉진 반응유형과 쇼핑성향

  • 김세희;이은영
    • Journal of Distribution Research
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    • v.4 no.3
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    • pp.33-46
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    • 2000
  • 본 연구는, 그 동안 간과되어 왔던 의류 상품의 판촉에 초점을 맞추어, 판촉의 여러 방법 별 소비자들의 반응 정도를 알아보고, 그 반응 경향이 소비자의 인구통계적 특성, 판촉에 대한 태도, 의복 쇼핑 성향, 기타 의복 구매 행동과 연관성을 가지는지를 규명함을 목적으로 한다. 수도권 거주 여성 444명을 대상으로 수집한 자료를 이용해 분석이 이루어졌다. 실증적 연구를 통해 다음과 같은 결과를 얻었다. 첫째, 판촉의 각 방법에 대한 소비자들의 반응 정도는 가격 할인이 가장 높았고 그 다음은 디스플레이, 쿠폰, 사은품, 백화점 패션쇼, 경품의 순서로 나타났다. 가격 할인, 디스플레이, 사은품, 쿠폰, 백화점 패션쇼 등 5가지 판촉 방법에 대한 소비자 반응 정도를 기준으로 군집분석한 결과 판촉에 대한 반응 유형에 있어 차이를 보이는 5개 집단을 규명할 수 있었다. 각 집단의 인구통계적 특성들 중에서는 소비자 자신의 학력과 자녀의 연령만이 집단간에 유의한 차이를 보였으며, 각 집단의 판촉 태도는 집단 간에 유의한 차이를 보였다. 둘째, 각 집단은 의복 쇼핑 성향 및 의복 구매 관련 정보원 이용에서 차이를 보였다. 결론에서는, 실증적 연구의 결과 판촉에 대한 소비자 반응 유형별로 인구통계적 특성, 판촉 태도, 의복 쇼핑 성향, 기타 의복 구매 행동에 차이가 있음을 알 수 있었으므로 의류 상품의 판촉 전략 수립시 표적 집단의 특성에 따라 판촉 방법 선택이나 판촉 정보 전달 경로 등을 조절하는 것이 필요함을 제언하였다. 예를 들어, 신중/경제적 쇼핑 성향을 가지며 판촉에 대한 태도가 호의적인 소비자들에 대해서는 다양한 정보 전달 경로를 통해 가격 할인이나 쿠폰을 제공하는 것이 좋은 판촉 방법이 될 것이며, 쾌락/유행 지향적이고 상표/품질을 중시하는 소비자들에 대해서는 잡지, 인적 정보, 카탈로그 등을 정보 전달 경로로 하여 디스플레이나 패션쇼를 통해 판매 촉진을 할 수 있을 것이다.0.10 $h^{-1}$과 0.09$h^{-1}$h-1이었고, 반감기는 각각 6.93 및 7.70시간으로 측정되었다. 각각의 농도에서 12시간 및 8시간 이후에는 g당 0.19$\mu\textrm{g}$ 및 0.18$\mu\textrm{g}$이하로 떨어짐을 알 수 있었다. Phosphamidon과 profenofos의 급성어독성은 profenofos가 높았고, BCF profenofos가 phosphamidon보다 약 100배 정도 높게 나타났으며, 배설속도는 phosphamidon이 profenofos보다 약 2배 정도 빨랐다.

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Effects of Aerosol Colistin Treatment of Pneumonia Caused by Multi-drug Resistant Acinetobacter baumannii (다약제 내성 Acinetobacter baumannii 에 의한 폐렴에서 Colistin 분무치료의 효과)

  • Choi, Hye Sook;Hwang, Yeon Hee;Park, Myung Jae;Kang, Hong Mo
    • Tuberculosis and Respiratory Diseases
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    • v.64 no.1
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    • pp.8-14
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    • 2008
  • Background: Acinetobacter infections are difficult to treat as they often exhibit multiple resistance to the antibiotics that are currently available for the treatment of pneumonia. Colistin is active against gram-negative bacteria, including the multiple drug resistant (MDR) Acinetobacter species. However, intravenous administration of colistin was abandoned because of its nephrotoxicity and neurotoxicity. The aims of this study were to examine the efficacy and safety of colistin administered by aerosol in the treatment of pneumonia caused by MDR Acinetobacter baumannii. Methods: We retrospectively reviewed the medical records of patients admitted to the intensive care unit (ICU) from Dec. 2006 to Aug. 2007 who had been diagnosed as suffering from pneumonia due to MDR Acinetobacter baumannii and had been treated with nebulized colistin. Results: 31 patients received aerosolized colistin. The average duration of the treatment was $14{\pm}7$ days and the daily dose of ranged from 225 mg to 300 mg. All patients received concomitant intravenous antimicrobial agents. The average length of the stay in the ICU was $34{\pm}21$ days and in the hospital $58{\pm}52$ days. The overall microbiological eradication was observed in 25 patients (80.6%). 14 of these (56%) were cured, and 11 (44%) were infected with other microorganisms. The overall crude mortality of the ICU was 48%. Nephrotoxicity and significant bronchial constriction did not occur in any patient during neublized colistin treatment. Conclusion: Nebulized colistin may be a safe and effective option in the treatment of pneumonia due to MDR Acinetobacter baumannii. Its role in therapy warrants further investigation in comparative studies.

The Evaluation of Radiation Therapy and Combined-modality Therapy for Non-small-cell Lung Cancer in Elderly (고령의 비소세포성폐암 환자의 방사선 및 병용치료에 대한 효과 평가)

  • Yoon, Won-Sup;Yang, Dae-Sik;Kim, Chul-Yong
    • Radiation Oncology Journal
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    • v.25 no.2
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    • pp.101-108
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    • 2007
  • [ $\underline{Purpose}$ ]: To compare radiation therapy alone to combined modality therapy about survival rate and tolerance of elderly patients ($70=or{\geq}$) with non-small-cell lung cancer (NSCLC). $\underline{Materials\;and\;Methods}$: Between 1998 and 2002, 57 patients given radiation therapy due to NSCLC (Stage III) were analysed retrospectively. Radiation therapy alone (RT), concurrent chemoradiation (CRT), and sequential chemoradiation (SCRT) was done to 33, 16 and 8 patients, respectively. Patients' median age was 74 (range $70{\sim}85$). Male and female are 51 patients and 6 patients, respectively. 23 patients were stage IIIa and 34 were stage IIIb. Patients' characteristic distribution of RT and CRT was not significantly different except mass size that RT has a bigger than CRT. The fraction size of radiation therapy was 1.8 Gy in CRT and $1.8{\sim}3\;Gy$ in other groups. Total radiation dose was $51{\sim}63\;Gy$ according to the fraction size. If the prescribed total radiation dose was successfully irradiated, we stated that it was completion of radiation therapy. $\underline{Results}$: 52 patients were dead. Median period of radiation therapy was as follow: RT, 35 days, CRT, 60.5 days and SCRT, 35 days. Overall median survival time (MST) was 10.1 months. The 1 yr- and 2 yr-overall survival rate was 39.8% and 17.6%, respectively. MST of RT, CRT and SCRT was 8.9, 8.2 and 11.7 months, respectively. The 1 yr survival rate of RT, CRT and SCRT was 38.4%, 37.5% and 50% (not significant). Patients given incomplete radiation therapy were 12 (RT, 5 CRT, 6 SCRT, 1). N stage (p=0.081) and the difference of treatment methods (p=0.079) were the factors affecting incompletion of radiation therapy, but it was not significant. In case of combined-agents chemotherapy, 4 of 8 ceased radiation therapy. T stage ($T{\geq}3$), mass size (${\geq}5\;cm$), Karnofsky performance scale (${\leq}70$) and completion of radiation therapy were the prognostic factors in uni- and multi-variate analysis. $\underline{Conclusion}$: In elderly patients with NSCLC, radiation therapy alone was a treatment method with similar survival period compared with other methods. Generally, patients given radiation therapy alone was tolerable to a treatment. Before planning concurrent chemoirradiation in elderly patients with NSCLC, physicians pay attention to a selection of patients and chemotherapy agents considering general condition and toxicity.