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        검색결과 1,407

        461.
        2018.04 구독 인증기관·개인회원 무료
        Silkworms, Bombyx mori L., have been traditionally used as an oriental medicine to manage diverse pathological conditions including dermatological problems in East Asia, in addition to the use of their cocoons for making fabrics. The “mature” silkworms of B. mori have recently been regarded as a potential health supplement due to gaining their edibility for humans by a newly-developed steaming method. Therefore, the present study was conducted to investigate the effects of a larval powder of steamed mature silkworms (SMSP) on skin pigmentation and melanogenesis. Orally administered SMSP of pistachio cocoon strain significantly and reduced abnormal pigmentation caused by ultraviolet B on the murine dorsal skin. SMSP also showed a potential anti-melanogenic efficacy in modulating UVB-induced melanogenesis.
        462.
        2018.04 구독 인증기관·개인회원 무료
        Methyl benzoate (MB) is a natural compound in many plants and shows insecticidal toxicity against various insect pests. We determined contact, fumigant, and repellent activities of MB against the sweetpotato whitefly Bemisia tabaci and the greenhouse whitefly Trialeurodes vaporariorum (Hemiptera: Aleyrodidae). Complete contact mortality was obtained by 4% MB. Contact mortality at 2% MB into eggs, 4th instar nymphs and adults were 69.4%, 91.6% and 80%, respectively. Fumigation of 2% MB killed 95% of adults. In addition, treatment of 4% MB repelled 60% adults. There was no significant different between two species. Our results suggest that MB has high potential as an natural pesticide for sustainable pest management in crop production.
        463.
        2018.04 구독 인증기관·개인회원 무료
        Fungus gnat, Bradysia impatiens is the most serious pest of different vegetable crops, mushroom and ornamental crops. In this study, we compared the control efficacy of two entomopathogenic nematode; Steinernema carpocapsae and Heterorhabdistis indica in Bradysia impatiens last instar maggots at 25℃ in laboratory. Our present study shows that, nematode infection and reproduction both were higher in the warm adapted nematode H. indica than the cold adapted S. carpocapsae. Therefore, entomopathogenic nematode H. indica can be use for control the Badysia impatiens as the efficient biological control agent.
        464.
        2018.04 구독 인증기관·개인회원 무료
        Mirinae is the most diverse subfamily within the family Miridae (Hemiptera: Heteroptera), and includes more than 4,000 species. In Korea, mirids were first recorded from Jeju Island in the mid-1960s. Since that study, numerous plant bug species from the Korean peninsula have been newly recognized and described. Previously, 101 species of Mirini were recorded from Korean peninsula. In this study, we provide an additional information of Mirini in Korea with a description of new species and new records.
        465.
        2018.04 구독 인증기관·개인회원 무료
        Bemisia tabaci is a vector of Tomato yellow leaf curl virus (TYLCV) but Trialeurodes vaporariorum is not. To determine the effect of TYLCV acquisition on vector and non-vector, we compared various physiological characteristics between two species. Our results showed that TYLCV acquisition significantly affected B. tabaci but not T. vaporariorum. The B. tabaci increased susceptibility against thermal stress but weakened chill coma recovery, shortening of longevity, low fecundity and abbreviated developmental time by virus acquisition. At the molecular level, B. tabaci increased hsp70 and hsp90 levels by TYLCV ingestion. However, T. vaporariorum did not shown any changes of those characteristics. Therefore, the physiological manipulation of TYLCV was specific to vector species but not non-vector species.
        466.
        2018.03 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        This paper on language learner strategies utilizes a little used quantitative, datamining technique called cluster analysis to investigate characteristics of groups of South Korean learners of English. After 71 students in three first-year university liberal arts English conversation courses completed the Strategy Inventory for Language Learning (SILL), and the number of learning strategies was reduced from 50 to 26 based on standard deviation (SD) results, the non-hierarchical (K-means) 3-cluster procedure was applied to the self-reported data. Following statistical analysis, each of the three cluster groups could be profiled according to achievement scores. At this point, six items emerged as particularly meaningful with regard to the latter, including direct strategies (a memory one and a cognitive one) and indirect strategies (two affective and two metacognitive). These strategies and their significance with reference to the local context as well as results previously reported in the literature are discussed. Finally, limitations of the study and implications for future research using cluster analysis are reported.
        5,200원
        467.
        2018.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        게임 플레이에서 몰입은 매우 중요한 개념이며 게임을 이루는 요소들 중 몰입에 많은 영향을 미치는 요소는 바로 컷씬이다. 컷씬은 재미와 감동을 주는 게임의 스토리를 플레이어에게 직접적으로 전달해준는 매개체 이다. 대부분의 게임에서 모든 플레이어는 같은 컷씬을 보게 된다. 본 연구는 플레이어의 감성 데이터를 바 탕으로 플레이어마다 다른 컷씬을 감상하게 하게 게임 플레이의 몰입을 증가시키는 실험을 검증하였다. 우리는 각 이벤트 후 보여지는 컷씬을 감상하기 전 인터페이스를 통해 플레이어의 각 상황에 대한 감성을 입력받아 실시간으로 보여지는 컷씬에 효과를 적용시켰다. 적용시켜지는 칼라 효과는 러셀의 감성모델과 그 감 성모델에 매칭되는 컬러표를 기반으로 구현하였다. 플레이어의 감성에 따라 컷씬은 달라지게 된다. 많은 연 구들이 게임에서의 몰입을 다루고 있으며 이계속 이루어 질 것이다. 본 연구는 게임에서 플레이어의 몰입증가에 새로운 시도가 될 것이다.
        4,000원
        468.
        2018.03 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        사용후핵연료을 건식처리하는 파이로프로세싱 중 전해정련 및 제련공정 후 발생되는 우라늄과 초우라늄 및 희토류 등의 염화물을 함유한 LiCl-KCl 공융염에는 특히 희토류 함량이 높기 때문에 유효자원으로 활용이 가능한 형태의 우라늄과 초우라 늄의 분리/회수가 쉽지 않다. 이러한 문제점을 해결하기 위해 본 연구에서는 LiCl-KCl-UCl3-NdCl3 시스템에서 산화제(K2CO3) 를 이용하여 UCl3를 산화물 형태로 전환한 후 전기화학적 방법을 이용하여 NdCl3를 금속형태로 분리하는 실험을 실시하였 다. 실험에 앞서, 이론적 평형계산을 수행하여 우라늄 염화물을 산화물로 전환하기 위한 실험조건을 결정하였다. 상기의 실 험에서 LiCl-KCl 내 UCl3는 첨가제의 주입량이 이론적 반응당량에 근접하였을 때 거의 대부분이 염내에서 염화물 형태로 존 재하지 않는 것으로 나타났다. 이후 액체금속음극을 이용하여 NdCl3를 금속형태로 전착시켰으며, 전착실험 후 투명한 용융 상의 LiCl-KCl 공융염과 갈색의 우라늄 산화침전물이 존재함이 확인되었다. 이러한 결과들을 통해 LiCl-KCl-UCl3-NdCl3 시스 템에서 우라늄 및 희토류를 각각 분리할 수 있는 방안을 수립할 수 있을 것으로 판단된다.
        4,000원
        469.
        2018.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The objective of this study was to determine the effect of various roughage sources on nutrient digestibility and enteric methane (CH4), and carbon dioxide (CO2) production in goats. Four castrated black goats (48.5 ± 0.6 kg) were individually housed in environmentally controlled respiration-metabolism chambers. The experiment design was a 4 × 4 balanced Latin square design with 4 roughage types and 4 periods. Alfalfa, tall fescue, rice straw, and corn silage was used as representative of legume, grass, straw, and silage, respectively. Dry matter digestibility was higher (p < 0.001) in corn silage than in alfalfa hay. Dry matter digestibility of alfalfa hay was higher than those of tall fescue or rice straw (p < 0.001). Neutral detergent fiber digestibility of tall fescue was lower (p < 0.001) than those of alfalfa, rice straw, or corn silage. Daily enteric CH4 production and the daily enteric CH4 production per kilogram of BW0.75, dry matter intake (DMI), organic matter intake (OMI), digested DMI, and digested OMI of rice straw did not differ from those of tall fescue but were higher (p < 0.001) than those of alfalfa or corn silage. Roughage type had no effect on enteric CO2 emission in goats. Straw appeared to generate more enteric CH4 production than legume or silage, but similar to grass.
        4,000원
        470.
        2018.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        말라위는 농업생산성 향상을 위해 관개시설 설치를 적극적으로 확대하고 있는데. 주로 외국의 원조에 의존하고 있다. 따라서 말라위의 효율적인 관개시설 구축을 위해 우리나라의 영산강유역농업종합개발사업(이하 영산강사업) 사례를 검토한 후 정책적 시사점을 제시하였다. 우리나라의 영산강사업은 유관기관들의 체계적인 협업 시스템으로 장기간에 걸쳐 시행되었다. 따라서 말라위의 중장기적인 관개시설 구축을 통한 농업생산성 향상을 위해서는 정부의 강력한 의지와 해당 사업을 주도적으로 시행할 수 있는 기관의 역할을 분명히 할 필요가 있다. 이를 위해서는 법적으로 규정해야 할 것이다. 현재 말라위의 사회경제적 여건은 우리나라의 영산강사업 추진 시기와는 매우 상이하다. 또한 한국의 영산강사업은 중장기적으로 걸쳐 시행되면서 각 과정에서 시행착오를 통한 노하우(know-how) 및 기술이 축적되었다. 따라서 말라위도 영산강사업과 같은 대규모 국책사업을 일괄적으로 시행하기 보다는 테스트 베드를 거쳐 말라위 여건에 맞게 시행할 필요가 있다. 영산강사업은 시행 초기에 환경문제가 크게 부각되지 않았지만, 90년대 후반부터는 ‘환경’에 대한 경각심이 커져 현재 영산강사업 5단계 설치는 중단된 상태이다. 따라서 말라위에서도 이러한 환경문제 및 제반 정치경제적 여건에 대한 면밀한 검토가 필요하다. 다만, 영산강사업은 벼농사를 위한 관개시설 위주의 사업이므로, 밭작물 위주의 관개시설은 그 형태 및 시사점이 달라질 수 있다 . 그리고 우리나라 영산강사업은 장기간에 걸려 축적된 노하우와 기술이 단계적으로 적용된 것으로 , 각 토목기술별로 말라위에 적용 가능한지는 추후 검토가 필요할 것이다 . 이러한 정책적 한계점은 추후 연구과제로 남겨둔다.
        4,200원
        471.
        2018.03 KCI 등재후보 구독 인증기관 무료, 개인회원 유료
        Salvia miltiorrhiza (Danshen) is perennial plant and commonly used in traditional Chinese medicine to treat numerous diseases like cardiovascular and cerebrovascular diseases, coronary heart disease, myocardial infarction, stroke and some viral diseases. Nevertheless, no study has been conducted on the antiviral properties of crude extract of Salvia miltiorrhiza against Influenza virus. In an attempt to identify new potential anti-influenza virus agents, 200 natural oriental herbal medicines were screened and we found that Salvia miltiorrhiza has a potential anti-influenza effect. Therefore, in this study, we investigated the protective effect of aqueous extract from Salvia miltiorrhiza against divergent influenza A subtypes using murine model of influenza A infection. Effective dose of aqueous extracts of Salvia miltiorrhiza in BALB/c mice displayed higher survival rate and lower lung viral titers when challenged with lethal doses of influenza A subtypes ({A/Aquatic bird/Korea/ W81/2005(H5N2)}, {A/PR/8/34(H1N1)}, {A/Aquatic bird/Korea/W44/2005(H7N3)} and {A/Chicken/ Korea/116/2004(H9N2)}). In vivo results exhibited that Salvia miltiorrhiza induced prophylactic effect in BALB/c mice against Influenza virus by disrupting viral replication or preventing viral infection by creating an antiviral state in the lungs. Taken together, the use of aqueous extracts of Salvia miltiorrhiza as an orally active antiviral agent, will be potential candidates for prophylactic treatments against Influenza A virus for humans and animals.
        4,000원
        472.
        2018.03 KCI 등재후보 구독 인증기관 무료, 개인회원 유료
        Cluster of differentiation (CD) 24 or heat stable antigen 24 (HSA) molecule is a mucin-type glycoprotein attached to the cell surface by glycosylphosphatidylinositol (GPI)-anchor, promoting adhesive interactions between cells or in extracellular matrix. The aim of this study was to determine the not yet fully identified porcine CD24 gene and protein structure using computational analysis and to validate variants reported in exons of CD24 gene using direct sequencing. A total of 59 samples belonging to Yorkshire, Landrace, Berkshire, Jeju black pig and wild boar were used in the study. Human CD24 mRNA sequences were used as a reference and subjected to BLAST searches to retrieve the orthologous expressed sequence tags (ESTs) or cDNA sequences against NCBI and Ensemble databases. Assembled ESTs and retrieved cDNA sequences for the porcine CD24 gene were used for specific BLAST search to determine its genomic structure. We found porcine CD24 gene to consist of two exons and a relatively long intron. Second exon of porcine CD24 gene had a long 3’ untranslated region (UTR) and was very similar to that of human, mouse, rat, and sheep. The sequence homology of porcine CD24 protein was 65.38-84.62%, when analyzed with amino acid sequences of rat, mouse, human, cattle, and sheep CD24 protein. N-terminal signal sequence, O-glycosylation sites and GPI-anchoring signal sites were also predicted in pig, which showed these motifs to be evolutionary conserved across the species. Variant analysis in exonic regions of porcine CD24 among the multiple breeds showed that only second exon contained eight SNPs and three insertions in a 3’ UTR. Taken together, this study reports putative porcine CD24 gene and its protein structure using in silico approaches, which will be helpful for any further functional studies.
        4,000원
        473.
        2018.01 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Cobalt-incorporated zeolitic imidazolate framework ZIF-8 was synthesized by a simple one-pot synthesis method at room temperature. Powder X-ray diffraction patterns and energy dispersive X-ray spectrum confirmed the formation of the bimetallic Co/Zn-ZIF structure. UV-Vis diffuse reflectance spectra revealed that the bimetallic ZIF had a lower HOMO-LUMO gap compared with ZIF-8 due to the charge transfer process from organic ligands to cobalt centers. A hydrolytic stability test showed that Co/Zn-ZIF is very robust in aqueous solution - the most important criterion for any material to be applied in photodegradation. The photocatalytic efficiency of the synthesized samples was investigated over the Indigo Carmine (IC) dye degradation under solar simulated irradiation. Cobalt incorporated ZIF-8 exhibited high efficiency over a wide range of pH and initial concentration. The degradation followed through three distinct stages: a slow initial stage, followed by an accelerated stage and completed with a decelerated stage. Moreover, the photocatalytic performance of the synthesized samples was highly improved in alkaline environment rather than in acidic or neutral environments, which may have been because in high pH medium, the increased concentration of hydroxyl ion facilitated the formation of hydroxyl radicals, a reactive species responsible for the breaking of the Indigo Carmine structure. Thus, Co/Zn-ZIF is a promising and green material for solving the environmental pollution caused by textile industries.
        4,000원
        474.
        2018.01 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 공기주입 이중피복온실과 관행 이중피복온실의 생육환경과 단열성능을 비교하기 위하여 수 행하였다. 두 온실의 온도, 상대습도, 포차, 이산화탄소농도, 일사량, 딸기 생산량 및 난방연료소비량을 비교하 였다. 공기주입온실이 관행온실보다 야간에 상대습도가 더 높고 포차는 더 낮게 나타나 딸기의 생육에 좋지 않은 환경을 보여주었다. 이산화탄소농도는 공기주입온실이 관행온실보다 더 높게 나타났으며, 이는 공기주입 온실이 더 밀폐되어 있어 환기량이 적기 때문인 것으로 판단된다. 관행온실의 광투과율이 77%로 공기주입온실 의 72%보다 더 높아 관행온실의 광환경이 더 우수한 것으로 나타났다. 관행온실의 딸기 생산량이 더 높게 나 타났으며, 이는 관행온실의 생육환경이 공기주입온실보다 더 우수한 결과로 판단된다. 난방연료는 공기주입온 실에서 더 적게 소모되어 공기주입온실의 단열성능이 더 우수한 것으로 나타났다.
        4,000원
        475.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Water and wastewater treatment has always been a challenging task due to the continuous increase in amount and the change in characteristics of the poorly biodegradable and highly colored organic matters, as well as harmful micro-organisms. Advanced techniques are therefore required to successfully remove these pollutants from water before reuse or discharge to receiving water bodies. Application of ozone, which is a powerful oxidant and disinfectant, alone or as part of advanced oxidation process depends on the complex kinetic reactions and the mass transfer of ozone involved. Micro- and nano bubbling considerably improves gas dissolution compared to conventional bubbles and hence mass transfer. It can also intensify generation of hydroxyl radical due to collapse of the bubbles, which in turn facilitates oxidation reaction under both alkaline as well as acidic conditions. This review gives the overview of application of micro- and nano bubble ozonation for purification of water and wastewater. The drawbacks of previously considered techniques and the application of the hydrodynamic ozonation to synthetic aqueous solutions and various industrial wastewaters are systematically reviewed.
        4,000원
        476.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        목적: 50세 이상에 해당하는 연구대상에서 성별에 따른 나이관련 황반변성의 초기와 후기 유병률과 위험 요인을 알아보고자 하였다. 방법: 제5기 국민건강영양조사(2010-2012) 원시자료의 총 조사대상자 25,534명 중 건강설문조사와 검진 조사를 모두 받은 50세 이상 남녀에서 결측치가 있는 대상을 제외한 7,599명(남자 3,263, 여자 4,336)을 연 구대상으로 하였다. 성별에 따른 초기 및 후기 나이관련 황반변성의 위험요인을 알아보기 위해 나이를 통제 한 상태에서 인구학적 특성, 전신질환, 검진조사에 관한 변수에 대해 로지스틱 회귀분석을 수행하였고 이 결 과에서 유의한 변수들만으로 다변량 로지스틱 회귀분석을 수행하였다. 결과: 나이관련 황반변성 초기의 유병률은 남자 8.8%, 여자 10.3%였으며 후기의 유병률은 남자 1.4%, 여자 0.7%였다. 초기 나이관련 황반변성에 대한 교차비는 남자에서 나이가 1세 증가할 때 1.043배, HDL (high-density lipoprotein)이 1mg/dL 증가할 때 1.010배, AST(aspartate aminotransferase)가 1IU/L 증 가할 때 1.011배, 비타민 D가 1ng/mL 증가할 때 1.020배 높아졌으며 Creatinine이 1mg/dL 증가할 때 0.446배 낮아졌고 여자에서는 나이가 1세 증가할 때 1.080배, B형간염표면항원 양성인 대상에서 1.960배 높아졌고 혈소판이 1Thous/uL 증가할 때 0.997배 낮아졌다. 후기 나이관련 황반변성에 대한 교차비는 남자 에서 나이가 1세 증가할 때 1.083배 높아졌고 B형간염표면항원 양성인 대상에서 3.436배 높아졌으며 여자 에서는 나이가 1세 증가할 때 1.126배 높아졌고 교육수준에서 저학력자보다 고학력자에서 2.480배 높았으며 혈소판이 1Thous/uL 증가할 때 0.991배 낮아졌다. 결론: 나이를 제외한 성별에 따른 초기 및 후기 나이관련 황반변성의 위험요인은 남자에서 초기는 AST와 HDL, 비타민 D였고 Creatinine의 증가는 교차비를 감소시켰고 후기는 B형간염표면항원 양성자에서 교차비 가 높게 나타났다. 여자에서 초기의 위험요인은 B형간염표면항원 양성이었고 후기는 교육수준이었으며 초기 와 후기 모두에서 혈소판 수치가 높아지면 교차비가 낮아지는 것으로 나타났다.
        4,000원
        477.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Porcine spermatogonial stem cells (SSCs) prefer three-dimensional (3D) culture systems to 2D ones for the maintenance of self-renewal. Of the many 3D culture systems, agar-based hydrogels are candidates for supporting porcine SSC self-renewal, and there are various types of agar powder that can be used. In this study, we sought to identify an agar-based 3D hydrogel system that exhibited strong efficacy in the maintenance of porcine SSC self-renewal. First, 3D hydrogels with different mechanics were prepared with various concentrations of Bacto agar, lysogeny broth (LB) agar, and agarose powder, and the 3D hydrogel with the strongest alkaline phosphatase (AP) activity and greatest increase in colony size was identified for the different types of agar powder. Second, among the porcine SSCs cultured in the different 3D hydrogels, we analyzed the colony formation, morphology, and size; AP activity; and transcription and translation of porcine SSC-related genes, and these were compared to determine the optimal 3D hydrogel system for the maintenance of porcine SSC self-renewal. We found that 0.6% (w/v) Bacto agar-, 1% (w/v) LB agar-, and 0.2% (w/v) agarose-based 3D hydrogels showed the strongest maintenance of AP activity and the most pronounced increase in colony size in the culture of porcine SSCs. Moreover, among these hydrogels, the strongest transcription and translation of porcine SSC-related genes and largest colony size were detected in porcine SSCs cultured in the 0.2% (w/v) agarose-based 3D hydrogel, whereas there were no significant differences in colony formation and morphology. These results demonstrate that the 0.2% (w/v) agarose-based 3D hydrogel can be effectively used for the maintenance of porcine SSC self-renewal.
        4,000원
        478.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Colorectal cancer (CRC) is the third most prevalent cancer in the world, and heme iron is known to promote the CRC in an animal model. This study was conducted to investigate the effects of ascorbic acid in the presence of hemin on the formation of pre-neoplastic lesions induced by azoxymethane (AOM)/disodium sulfate (DSS) in mice. After acclimation for 1 week, five-week old mice received three s.c. injections (0-2 weeks of the experiment) of AOM [10 mg/kg body weight (BW)] weekly and were treated with 2% DSS in drinking water for the next week to induce aberrant crypt foci (ACF). All animals were fed the AIN-76A purified rodent diet for experimental period of 6 weeks. Experimental groups were then divided into three groups: carboxymethylcellulose (CMC) alone (control), CMC + Hemin, CMC + Hemin + ascorbic acid (AA). The CMC was used as a solvent for hemin. The daily doses were 534 mg/kg BW hemin and 246 mg/kg BW ascorbic acid administered orally. After the colonic mucosa were stained with methylene blue, aberrant crypt foci (ACF), aberrant crypt (AC) and polyps were counted. Lipid peroxidation in liver was evaluated by the thiobarbituric acid-reactive substances (TBARS) assay. The numbers of ACF, AC and large ACF (≥4 AC/ACF) per colon increased in the hemin group compared to the control group, while they decreased significantly in the hemin + ascorbic acid group compared to the control group or hemin group (p<0.01). The number of polyps/colon in the hemin + AA group was significantly decreased compared to the hemin group (p<0.05). In the liver, the TBARS value of the hemin group was significantly higher than that of the control group (p<0.01). Additionally, the TBARS value of the hemin + AA group decreased slightly compared to that of the hemin group. Taken together, these results suggest that hemin can promote colon carcinogenesis in a mouse model and that ascorbic acid has a protective effect against hemin-promoted colon carcinogenesis.
        4,000원
        479.
        2017.12 KCI 등재후보 구독 인증기관 무료, 개인회원 유료
        Excessive iron can promote the production of free radicals, thereby leading to harmful effects on cancer and aging. Ascorbic acid is not only an antioxidant but also a co-factor of iron absorption. The effect of iron-overload with ascorbic acid on experimental colon carcinogenesis was investigated in male ICR mice. Animals were treated weekly with azoxymethane (AOM, 10 mg/kg b.w.) at 0, 1, and 2 week and then drunk 2% dextran sodium sulfate (DSS)-containing water for the next 1 week. There were four experimental groups: carboxymethylcellulose (CMC) alone (control), CMC + ascorbic acid (AA), CMC + Fe, CMC + Fe + AA. The animals fed on AIN-76A purified rodent diet for six weeks. AA or Fe2O3 at the dose of 450 mg/kg b.w. were daily and orally treated for 6 weeks. The colonic mucosa was stained with methylene blue and then aberrant crypt foci (ACF) and polyps were counted. Thiobarbituric acid-reactive substances (TBARS) in serum and liver were determined. Iron concentration in liver was measured by inductively coupled plasma spectrophotometer. Fe-overload with AA strongly increased liver iron contents compared to control or Fe group (p<0.05). There were no significant differences in the number of ACF or polyps among all groups, although ironoverloaded groups had slightly higher numbers compared with the control or AA group. TBARS values in the liver were increased in the iron-overloaded groups compared to control and AA only group (p<0.05), but serum TBARS values were not changed. These results indicate that the excessive iron treatment did not affect the experimental colon carcinogenesis regardless of presence of AA in mice.
        4,000원
        480.
        2017.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        ZnMgBeGaO/Ag/ZnMgBeGaO multilayer structures were sputter grown and characterized in detail. Results indicated that the electrical properties of the ZnMgBeGaO films were significantly improved by inserting an Ag layer with proper thickness (~ 10 nm). Structures with thicker Ag films showed much lower optical transmission, although the electrical conductivity was further improved. It was also observed that the electrical properties of the multilayer structure were sizably improved by annealing in vacuum (~35% at 300 oC). The optimum ZnMgBeGaO(20nm)/Ag(10nm)/ZnMgBeGaO(20nm) structure exhibited an electrical resistivity of ~2.6 × 10−5 Ωcm (after annealing), energy bandgap of ~3.75 eV, and optical transmittance of 65%~ 95 % over the visible wavelength range, representing a significant improvement in characteristics versus previously reported transparent conductive materials.
        3,000원