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        검색결과 216

        101.
        2009.10 구독 인증기관·개인회원 무료
        We cloned and characterized two peroxiredoxins (Prxs), BiPrx1 (a 1-Cys Prx) and BiTPx1 (a 2-Cys Prx) from the bumblebee Bombus ignitus. The BiPrx1 gene consists of 5 exons, encoding 220 amino acid residues with one conserved cysteine residue. The BiTPx1 gene consists of three exons, encoding 195 amino acid residues with 2 conserved cysteine residues. Recombinant BiPrx1 (27 kDa) and BiTPx1 (25 kDa), expressed in baculovirus-infected insect Sf9 cells, reduced H2O2 in the presence of electrons donated by dithiothreitol. Unlike BiTPx1, however, BiPrx1 did not show reduction activity when thioredoxin was used as the electron donor. Both BiPrx1 and BiTPx1 protected super-coiled DNA from damage by metal-catalyzed oxidation (MCO) in vitro. Tissue distribution analyses showed the presence of BiPrx1 and BiTPx1 in the fat body, midgut, muscle and epidermis, but not in the hemolymph, suggesting that BiPrx1 and BiTPx1 are not secretable. When H2O2 was injected into B. ignitus bees, BiPrx1 and BiTPx1 transcripts were acutely up-regulated in the fat body tissues. We also demonstrated regulation of BiPrx1 and BiTPx1 expression via reduction of transcript levels in the fat body with RNA interference (RNAi). Under H2O2 overload, the RNAi-induced BiPrx1 knock-down B. ignitus worker bees showed up-regulated expression of BiTPx1. Reciprocally, BiTPx1 RNAi knockdowns showed up-regulated BiPrx1 expression in the fat body. These results indicate that loss of expression of BiPrx1 or BiTPx1 is compensated by up-regulation of expression of the other peroxidase in response to H2O2 overload.
        103.
        2009.08 구독 인증기관·개인회원 무료
        The objective of this experiment was to evaluate growth performance in dairy goats (Saanen) fed total mixed ration (TMR) of different nutrition levels. Twenty four growing female goats of 8 months of age were randomly assigned to one of four TMRs; low energy-low crude protein (CP) TMR (control), high energy-low CP TMR (T1), low energy-high CP TMR (T3) and high energy-high CP TMR (T4). The content of total digestible nutrients (TDN) and CP in the control diet were 64% and 12%. The TDN content of the high energy TMR was 72% and the CP content of the high CP TMR was 14%. Feed intakes were 1,194g, 1,060g and 1,124g for T1, T2 and T3, respectively, being higher than control (1,039g). Average daily gain was also numerically higher for T1 (170.2g), T2 (114.5g) and T3 (154.9g) than for control (109.0g). The difference of average daily gain between T1 and control was statistically significant (P<0.05). Although there were no significant differences in feed intake (% of body weight) between treatments, feed conversion ratios showed different responses; T1 (7.01) and T3 (7.26) being higher than T2 (9.26) and control (9.53). The increases of heart girth were 11.8㎝, 10.0㎝ and 11.4㎝ for T1, T2 and T3, respectively, being higher than control (8.1㎝).
        104.
        2009.08 구독 인증기관·개인회원 무료
        We measured cobalt content in sorghum (Sorghum bicolor (L.) Moench.) by atomic absorption spectrophotometry: their absorbance and back ground values. These analyses were with AA-680 of Shimadzu. The mode was BGC; wave length, 240.8 ㎚, 240.7 ㎚, 240.6 ㎚, respectively. The recommended wave length is 240.7 ㎚ for Co analysis. It was done through several ratios among 4 factors; mean of absorbance(AM), standard deviation of absorbance (AS), mean of background(BM), standard deviation of background.(BS). The result was t㏊t 240.6 ㎚ was the favourable. And t㏊t of 240.8 ㎚ was better t㏊n t㏊t of 240.7 ㎚ for the Co analysis.
        107.
        2008.10 구독 인증기관·개인회원 무료
        Metamorphosis is a development process involving the programmed cell death of obsolete larval organs. Aspartic proteinase cathepsin D (BmCatD) is involved in the silkworm Bombyx mori metamorphosis. Here we show a novel functional role of cysteine proteinase cathepsin B during B. mori metamorphosis. The B. mori cathepsin B (BmCatB) was expressed in the fat body, epidermis, ovary, testis, and hemocyte of the larval and pupal stages. The BmCatB was ecdysoneinduced, expressed in the fat body of the molting, the final larval instar and pupal stages, and its expression led to programmed cell death. RNA interference (RNAi)-mediated BmCatB knock-down inhibited the programmed cell death of larval and pupal fat body, resulting in the arrest of larval-pupal transformation. BmCatB RNAi is up-regulated the expression of BmCatD. Based on these results we concluded that BmCatB is critically involved in the histolysis of the larval and pupal fat body, indicating that BmCatB and BmCatD are mutally regulated during silkworm metamorphosis.
        112.
        2007.03 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        국내 경수로원전 1차 냉각재와 중저준위 방사성폐기물 내 핵종방사능비에 대한 유관성을 검토하고자 특수하게 제작된 RCS sampling kit를 이용하여 원전 정상운전기간 동안 핵종을 포집하였다. 시료채취는 경수로형 전 원자력 발전소를 대상으로 2004년과 2005년에 걸쳐 시료를 채취하였고, 방사화학적 방법인 시료 전처리 및 핵종분리를 통하여 핵종 방사능을 분석하였다. RCS sampling kit 내 필터와 수지에서 분석된 핵종 방사능비는 각각 2.32-2와 7.3E-1을 보였으며, 동일주기 내 발생된 중 저준위 방사성폐기물인 농축폐액, 폐수지, 잡고체시료 내 핵종 방사능비는 각각 6.3E-1, 6.7E-1 및 5.7E-2로 시료유형 에 따라 1차 냉각재와 유사성을 갖는 것으로 확인하였다.
        4,000원
        115.
        2006.06 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        4,600원
        116.
        2006.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        It has been reported that light-emitting diodes(LED) can be used in the treatment of oral diseases. Although bio-stimulatory effects of LED irradiation such as promotes stimulation of wound healing have been well known, there are few reports about molecular mechanism associated with cell cycle by LED irradiation. The purpose of present study was to examine the molecular event in cell cycle of LED irradiation on primary human gingival fibroblast(hGF) in vitro. The source of light for irradiation was a continuous-wave LED emitting at a wavelength of 635nm, and manufactured that energy density was 5mW/cm2 on sample surface. The hGF were irradiated for 1 hour at 37℃ in 5% CO2 humidified chamber. Experimental samples were acquired at 0 (right after irradiation), 8 and 24 hour after irradiation. To investigate the molecular mechanisms associated with cell cycle, growth phase was determined by flow cytometry and mRNA expression of cyclin A, cyclin B, cyclin D1, cyclin E, cdc2, PCNA, p18, p27, p21, and p53 were determined by real time RT-PCR. Flow cytometric analysis demonstrated the percentage of cells in the G1 and S phase were decreased, but the G2 phase increased, which showed cells irradiated by LED were transitioned from S to G2 phase. For mRNA expression, cyclin B, cdc2, PCNA and p53 were increased at 0 hour after irradiation, and most of cell cycle molecules were increased at 8 hour after irradiation. At 24 hour after irradiation, cyclin A, cyclin E, PCNA and p18 were increased. Taken together, LED irradiation induced proliferation of hGF cells through transition from S to G2 phase.
        4,000원
        118.
        2005.10 KCI 등재 구독 인증기관·개인회원 무료
        The purpose 01' pl'esent study was to examine the molecular events in apoptosis by CoCl2, mimicking hypoxic cond ition and recovering effects by LED ir l'adiation on Human SH-SY5Y neuroblastoma cells The SOUl'ce 0 1' light for ir l'adiation was a continuous-wave LED emitting at a wavelenl양h of 590 nm, and manufactured that ene rgy density was 5 mW!cm2 on sample surface, After ir l'adiation, cell viabi lity was measured with BrdU , cell morphol ogy was examined with Diff- Quik staining, cell signaling was monitored with various apoptosis-related molecules using RNase Pl'otection Assay(RPA) , W11en treated with CoC12, apoptotic induction was found in the SH-SY5Y cells in a concentration-dependent and time-dependent manner , Diff-Quik s taining was revealed that DNA fragmentation re presented apoptosis was examined in CoC12-tl'eated group, Moreover, RPA assay of SH-SY5Y cclls lIs ing val'iolls apoptosis-related molecllles showed that the apoptotic cell population was mcreased J-loweve. there was sorne signifïcant change in LED irradiatied cells aftel' treatement of CoC12 The main mechanism for Lhese a poptosis appearecl to be mito c hondriεt - m ecliated pathway, such as cytochrome- c‘ caspase-9, caspase-3, pro-apototic protein ßax, anti-apototic protein Bcl-2, and death receptor• mediated pathway, such as Fas, cas pase- 8, a ncl TNFRl These results demonstrate that CoCI2 induce apoptosis in SH-SY5Y via different dual apop tosis pathway through death receptor pathway as well as mitochondria- dependent pathway and LED irradiation can recl llces the CoCl2-induced apoptosis by blocking their internal signaling pathway