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        검색결과 101

        41.
        2018.11 구독 인증기관·개인회원 무료
        In general, the shape of cumulus-oocyte-complexes (COCs) at germinal vesicle (GV) stage is important roles on meiotic maturation of porcine oocyte during in vitro maturation (IVM). Then, mitochondria produce reactive oxygen species (ROS) such as superoxide from electron transport system during oocyte maturation. ROS levels on oocytes are regulated by various antioxidant enzymes in cumulus cells (CCs). However, the effect of mitochondria derived superoxide production from CCs during IVM of porcine oocyte has not been reported. Firstly, we divided groups according to large number of CCs (Grade 1: G1) and small number of CCs (Grade 2: G2). Then, we counted cumulus cells of G1 and G2 oocyte by using haemocytometer. The oocyte maturation rate was significant decreased (p < 0.05) in G2 oocytes than that of G1 oocytes. We measured mitochondria derived superoxide in G1 and G2 COCs by using Mito-SOX staining. Mitochondrial superoxide was higher in G2 COCs than G1 COCs. Then, the mRNA expression levels of antioxidant enzymes (SOD1, SOD2 and PRDX3) in G2 COCs were decreased compared to G1 COCs. To reduce mitochondria derived superoxide, we used Mito-TEMPO as mitochondrial superoxide scavenger. Oocyte maturation rates in both G1 and G2 groups treated with Mito-TEMPO were increased than that of non-treated groups. Mitochondrial superoxide was lower in G1 and G2 groups treated with Mito-TEMPO than that of non-treatment groups. The mRNA expression levels of antioxidant enzymes in G1 and G2 COCs treated with Mito-TEMPO were increased compared to non-treated groups. Based on these findings, we suggest that reduction of mitochondria derived superoxide by Mito-TEMPO assists maturation competence in porcine oocytes.
        42.
        2018.10 구독 인증기관·개인회원 무료
        The mandible character of the Lucanidae is vary by considering of developmental difference in male individual specimen. Especially, species of Genus Cyclommatus Parry, 1862 presents strong mandibular allometry. In this research, The species group which related to Cyclommatus montanellus Möllenkamp, 1904 has been evaluated for the first time in this research with inner teeth composition and positioning to establish clear taxonomic key to each species.
        44.
        2017.05 구독 인증기관·개인회원 무료
        An intensive analysis was conducted of the maternal lineages of the Jeju native pigs (JNPs). A total of 100 mtDNA sequences from Asian wild boars (AWB), European wild boars (EWB), Asian domestic pigs (ADP), European domestic pigs (EDP), and JNPs were used for the phylogeny and network analyses. Two distinct JNP groups were found JNPA and JNPE in the Asian and European cluster. The maternal lineage of JNPE was the closest to that of EWB and a clear haplogroup sharing an identical haplotype (hap16) among 15 individuals of JNPE and 2 individuals of EWB was identified. However, except for hap18, no EDP shared any identical haplotypes with JNPE, suggesting that no obvious maternal contribution of EDP has occurred in JNPE in recent years. The possible existence of an additional and unknown path of maternal lineage from EDP into JNPE could therefore be postulated, in addition to those from AWB and ADP into the JNPA groups. Thus, JNPE appeared to have a pure maternal lineage that had no recent contact with EDP, and both the JNPA groups and JNPE are pure Jeju native pigs.
        47.
        2016.09 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        This paper adopts a multi-factorial analysis and investigates English dative alternations in Korean EFL learners’ writings, by directly comparing dative alternations of native speakers and those of Korean EFL learners’ writings. Two corpora were chosen for the comparison: the Switchboard corpus (written sections) and the Korean component of the TOEFL11 corpus. After all the sentences with dative alternations were extracted from these two corpora, and seventeen linguistic factors were manually encoded, the data were statistically analyzed in R. This paper was theoretically based on the concept of interlanguage in the Second Language Acquisition and Competition Model of Bates and MacWhinney (1982, 1989). Through the analysis, the following facts were observed: (i) the Korean EFL learners used ditransitive constructions more frequently than prepositional constructions, (ii) eight main factors and four interactions with the L1 were statistically significant, and (iii) the ditransitive constructions which the Korean EFL learners used were closer to the prepositional constructions rather than the ditransitive constructions in Korean.
        6,100원
        48.
        2016.06 구독 인증기관 무료, 개인회원 유료
        In the present study, we evaluated the effect of CGM on osteogenic differentiation of cultured osteoblasts, and determined whether combination treatment with LLLT had synergistic effects on osteogenic differentiation. The results indicated that CGM promoted proliferation, differentiation, and mineralization of osteoblasts at the threshold concentration of 10 μg/ml; whereas, CGM showed cytotoxic properties at concentrations above 100 μg/ml. ALP activity and mineralization were increased at concentrations above 10 μg/ml . CGM in concentrations up to 10 μg/ml also increased the expression of osteoblast-activated factors including type I collagen, BMP-2, RUNX2, and Osterix. The CGM (50 μg/ml) and LLLT (80 mW for 15 sec) combination treatment group showed the highest proliferation levels, ALP activity, and mineralization ratios. The combination treatment also increased the levels of phosphorylated forms of p38, ATF2, PKD, ERK, and JNK. In addition, the osteoblast differentiation factors including type I collagen, BMP-2, RUNX2, and Osterix protein levels were clearly increased in the combination treatment group. These results suggested that the combination treatment of CGM and LLLT has synergistic effects on the differentiation and mineralization of osteoblastic cells.
        4,000원
        49.
        2016.03 구독 인증기관 무료, 개인회원 유료
        OSCC is currently the most common malignancy of the head and neck, affecting tens of thousands of patients per year worldwide. Natural flavonoids from plants are potential sources for novel anti-cancer drugs. Icariin is the active ingredient of flavonol glycoside, which is derived from the medical plant Herba Epimedii. A metabolite of icariin, icariside II exhibits a variety of pharmacological actions, including anti-rheumatic, anti-depressant, cardiovascular protective, and immunomodulatory functions. However, the exact mechanism causing the apoptosis-inducing effect of icariside II in OSCC is still not fully understood. In the present study, we assessed the anti-cancer effect of icariside II in OSCC cell lines by measuring its effect on cell viability, cell proliferation, and mitochondria membrane potential (MMP). Icariside II treatment of OSCC cells resulted in a dose- and time-dependent decrease in cell viability. Hoechst staining indicated apoptosis in icariside II-treated HSC cells. Icariside II inhibited cell proliferation and induced apoptosis in HSC cells, with significant increases in all present parameters in HSC-4 cells. The results clearly suggested that icariside II induced apoptosis via activation of intrinsic pathways and caspase cascades in HSC-4 cell lines. The collective findings of the study suggested that Icariside II is a potential treatment for OSCC; in addition, the data could provide a basis for the development of a novel anti-cancer strategy.
        4,000원
        50.
        2015.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The English dative alternation, which involves an alternation between the double object construction (DC) and the adpositional construction (AC), has been known to be one of the most problematic areas for L2 learners. This paper investigates the factors influencing the Korean English as a foreign language learners’ choices between the two constructions. The Korean section of the TOEFL11 corpus was used and sentences with dative constructions were extracted from the corpus. Nine factors were then encoded and analyzed with a generalized linear mixed-effect model. From the analysis, the following facts were observed: (1) Korean EFL learners’ choice between the DC and the AC was influenced by five factors: animacy of theme, definiteness of theme, pronominality of recipient, length difference between theme and recipient, and individual verbs; (2) despite some similarities in choice of alternation between Korean EFL learners and ENL speakers, the two groups also exhibited differences, and (3) these differences originated from the different effects of these factors.
        5,700원
        52.
        2015.10 구독 인증기관·개인회원 무료
        Athetis dissimilis (Hampson) (Lepidoptera: Noctuidae) [뒷흰날개담색밤나방] was attracted to pheromone traps for Euzophera batangesis (Lepidoprera Pyrimidae) [밤알락명나방], when occurrence of E. batangesis was monitored in sweet persimmon orchard with its pheromone, (Z)-9-tetradecenol (Z9-14OH), (Z9,E12)-9,12-teradecadienol (Z9,E12-14OH) and their mixture. With the components, we monitored the seasonal occurrence of A. dissimilis, tested response of the moth to single or mixed components, and compared efficacy of three different types of traps. A. dissimilis was trapped on May 14 for the first time. First occurrence peak was observed during June 4-24 and second peak during August 20 – September 10. A. dissimilis was attracted to single component of Z9-14OH and Z9,E12-14OH and to their mixture at Jinju, Sancheong, and Sacheon. In trap efficacy tests, delta traps with white color caught most number of the moths significantly at Sacheon. However, at Sancheong, there was no statistical difference among the traps, although funnel trap caught most number of A. dissimilis. Pest status of A. dissimilis is not known eg. whether it is a pest of persimmon or other fruits. However, with Z9-14OH, E9,E12-14OH and their mixture, it is expected to be monitored and controlled.
        53.
        2015.01 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Carbon aerogel is a porous carbon material possessing high porosity and high specific surface area. Nitrogen doping reduced the specific surface area and micropores, but it furnished basic sites to improve the CO2 selectivity. In this work, N-doped carbon aerogels were prepared with different ratios of resorcinol/melamine by using the sol-gel method. The morphological properties were characterized by scanning electron microscopy (SEM). Nitrogen content was studied by X-ray photoelectron spectroscopy (XPS) and the specific surface area and micropore volume were analyzed by N2 adsorption-desorption isotherms at 77 K. The CO2 adsorption capacity was investigated by CO2 adsorption-desorption isotherms at 298 K and 1 bar. Melamine containing N-doped CAs showed a high nitrogen content (5.54 wt.%). The prepared N-doped CAs exhibited a high CO2 capture capacity of 118.77 mg/g (at resorcinol/melamine = 1:0.3). Therefore, we confirmed that the CO2 adsorption capacity was strongly affected by the nitrogen moieties.
        4,000원
        56.
        2014.04 구독 인증기관·개인회원 무료
        Severe fever with thrombocytopenia syndrome (SFTS) is an emerging disease, causing high fever, thromobocytopenia, leukopenia, gastrointestinal simptoms (vomiting, diarrhea), hemorrhage and multiorgan dysfunction. It was known that Haemaphysalis longicornis (H. longicornis), a major tick in Korea, is the principal vector for severe fever with thrombocytopenia syndrome virus (SFTSV). Firstly, to investigate the existence and prevalence of SFTSV in the country, we collected the ticks in 9 provinces in South Korea and detected SFTSV from H. longicornis ticks from 2011 to 2012. And we also investigated SFTSV infection in ticks collected from healthy humans without SFTS symptom and their residential areas. From the former study, we collected 13,053 ticks, and H. longicornis (90.8%, 11,856/13,053) was the most abundant among them. The minimum infection rate (MIR) of SFTSV in H. longicornis was 0.5% (59 pools). From the later study, totally 422 ticks of 8 species were collected from humans and at their neighborhood throughout the nation from May to October, 2013 and SFTSVs were detected from 12 pools (5.7% MIR) by RT-PCR. Finally, we diagnosed 35 patients by detecting SFTSV gene with their sera, and isolated 26 SFTSVs among them in 2013. These findings indicate that SFTSVs are prevalent and SFTS is probably endemic in Korea.
        57.
        2013.10 구독 인증기관·개인회원 무료
        We are currently developing the smart mosquito counter device (height 1080mm × width 560mm × diameter 320mm, 220V 60Hz 30W), which can attract the blood sucking female mosquitoes by emitting CO2 gas (300ml/min), can count the number of the captured mosquitoes by an infra-red beam area sensor, and can send the captured mosquitoes’ number through the CDMA module at real time. We operated the 8 – 16 devices with mosquito sensor networks and a server at the Youngdeungpo-gu areas in Seoul city of south Korea for three years (2011-2013) and we could efficiently control mosquitoes at the high mosquito density area based on the mosquito sensor’s data. We found that the accuracy of the device was about over 93% compared the real mosquito data and transmitted data by CDMA. We also found the water reservoir areas to control floods in Seoul metro city had relatively higher mosquito density than other normal areas, because those flat water areas were preferred by mosquitoes. Because our pest control office knew the mosquito occurrence peak times and areas from mosquito data transmitted by the mosquito sensor devices, we efficiently controlled mosquito larva and adults at the right time. We could accomplish very systematic mosquito control policy and we had the high credibility with the results. Based on the mosquito occurrence data, we selectively and scientifically controlled mosquitoes. Therefore, we reduced pesticide usage and saved annually pesticide expenses up to 2/3. Conclusively, if there is no mosquito, we don’t have to control mosquitoes.
        58.
        2013.10 구독 인증기관·개인회원 무료
        A surveillance of chigger mites was conducted to clarify the incidence of scrub typhus vectors by new chigger mite collecting traps instead of trapping wild rodents for surveillance from each 4 collection points of 5 regions from September to November 2012 in Korea. During the surveillance period, 2,829 chiggers were collected and 10 species of 4 genera were identified. The first appearance of chigger mite and patients was 39 week (9.19~9.25) and the density of chigger mites had the peak in 43 week (10.17~10.23) and the density of patients had the peak in 44 week (10.24~10.30), respectively. In Goryeong-gun, a total of 1,797 mites representing 4 genera and 6 species were collected and the predominant species were Leptotrombidium scutellare (86.0%), L. pallidum (6.5%) and L. palpale (4.7%) whereas, In Gurye-gun, a total of 89 mites representing 2 genera and 3 species were collected and the predominant species were L. scutellare (46.5%) and L. palpale (36.2%) in similar to the natural environment. The high collecting rates were recorded at rice field (71.8%) and waterway (11.6%). This result shows that the surveillance of scrub typhus vectors by new chigger mite collecting trap is useful as an eco-friendly method.
        59.
        2013.10 구독 인증기관·개인회원 무료
        We investigated the prevalence of severe fever with thrombocytopenia- syndrome virus (SFTSV) and geographical distribution of ixodid ticks from 25 regions of the Korea during 2011-2012. We collected 25,940 ixodid ticks with 3 genera and 7 species using dry ice bait trap and flagging. Among them, Genus Haemaphysalis, Ixodes and Amblyomma counted 25,821 (99.5%), 118 (0.5%) and 1 (<0.0%). Genus Haemaphysalis consisted of 4 species, H. longicornis (90.4%), H. flava (9.2%), H. formosensis and H. hystricis (<0.1%). Genus Ixodes consisted of 2 species, I. nippoenesis (0.4%) and I. persulcatus (0.1%). Only one Amblyomma testudinarium was collected. The highly infested sites were grassland (50.1%) and mixed stand forest (20.3%). Minimum infection rate (MIR) of SFTSV in H. longicornis was 0.5% in Korea and this rate was similar to that in China (0.46%). Our results showed that H. longicornis is a major vector of SFTSV and its surveillance will be needed at high risk area.
        60.
        2013.09 구독 인증기관 무료, 개인회원 유료
        Bile acids and synthetic bile acid derivatives induce apop-tosis in various kinds of cancer cells and thus have anti-cancer properties. Recently, it has been suggested that autop-hagy may play an important role in cancer therapy. How-ever, few data are available regarding the role of autophagy in oral cancers and there have been no reports of autophagic cell death in OSCCs (oral squamous cell carcinoma cells) in-duced by HS-1200, a synthetic bile acid derivative. We thus examine whether HS-1200 modulates autophagy in OSCCs. Our findings indicate that HS-1200 has anticancer effects in OSCCs, and we observed in these cells that autophagic vacuoles were visible by monodansylcadaverine (MDC)and acridine orange staining. When we analyzed HS-1200-treated OSCC cells for the presence of biochemical markers, we observed that this treatment directly affects the conversion of LC-3II, degradation of p62/SQSTM1 and full-length beclin-1, clea-vage of ATG5-12 and the activation of caspase. An autop-hagy inhibitor suppressed HS-1200-induced cell death in OSCCs, confirming that autophagy acts as a pro-death signal in these cells. Furthermore, HS-1200 shows anticancer acti-vity against OSCCs via both autophagy and apoptosis. Our current findings suggest that HS-1200 may potentially cont-ribute to oral cancer treatment and thus provide useful infor-mation for the future development of a new therapeutic agent.
        4,000원
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