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        검색결과 186

        81.
        2011.10 구독 인증기관·개인회원 무료
        The objective of this study was to evaluate in vitro production of bovine embryos in Hanwoo. Oocytes were collected by ovum pick up (OPU) from ovaries of genetically high-value Hanwoo or by needle puncture from ovaries of slaughtered cattle. OPU was done every 3 4 days duing experimental period and collected oocytes were fertilized in vitro in both OPU and needle puncture groups. First, We compared the in vitro maturation rate in two groups (Experiment 1). 545 oocytes were recoverd from 4 females by 32 trials of OPU and then 433 oocytes were shown MⅡ stage after in vitro maturation (79.4%). In case of needle puncture group, 1905 oocytes were collected and then 1420 oocytes were matured to MⅡ stage during in vitro culture(74.5%). Second, we compared the developmental rate to blastocyst in two groups (Experiment 2). 1420 oocyte by needle puncture were fertilized with frozen-thawing semen; the cleavage rate 24 48 h after in vitro fertilization (IVF) was 88.6% and blastocyst development rate was 20.5% in needle puncture group. Even though there is lower cleavage rate after IVF in OPU group (84.8%), blastocyst development rate was higher compared with needle puncture group (26.4%). In conclusion, Blastocyst developmental rate could be increased by OPU than classical method of needle puncture. Improvement of bio-technique in collecting oocytes could be applied to understand the reproductive physiology in cattle, expecially Hanwoo. Therefore, further investigation should be done to clarify the efficiency and advantage of OPU involved in reproduction in animals and human being. This research was suppoted by Imsil-gun agricultural technology service center.
        82.
        2011.09 구독 인증기관 무료, 개인회원 유료
        This study was undertaken to evaluate the relationship between in vitro maturation and plasminogen activators (PAs) activity on porcine cumulus-oocytes complexes (COCs) exposed to oxidative stress. When COCs were cultured in maturation medium with hydrogen peroxide (H2O2), the proportion of the germinal vesicle breakdown (GVBD) and oocytes maturation were decreased with addition of H2O2, and were significantly (p<0.05) lower in medium with 0.1 mM H2O2 than control group. Also, the rate of degenerated oocytes was increased in as H2O2 concentration increased. When COCs were cultured for 48 h, three plasminogen-dependent lytic bands were observed: tissue-type PA (tPA); urokinase-type PA (uPA); and tPA-PA inhibitor (tPA-PAI). PA activity was quantified using SDS-PAGE and zymography. When H2O2 concentration was increased, tPA and tPA-PAI activities also increased in porcine oocytes cultured for 48 h, but not uPA. In other experiment, embryos were divided into three groups and cultured in (1) control medium, (2) control medium with 1.0 mM H2O2 and (3) control medium with 1.0 mM H2O2 along with catalase in concentrations of 0.01, 0.1, and 1.0 mg/ml, respectively. H2O2 decreased the rate of GVBD and maturation in porcine COCs but catalase revealed protective activity against oxidative stress caused by H2O2. In this experiment, tPA and tPA-PAI activities were higher in media with 1.0 mM H2O2 alone. Increasing concentration of catalase decreased tPA and tPA-PAI activities in porcine oocytes. These results indicate that the exposure of porcine follicular oocytes to ROS inhibits oocytes maturation to metaphase-II stage and increase the oocytes degeneration. Also, we speculated that increased ROS level may trigger tPA and tPA-PAI activities in porcine oocytes matured in vitro.
        4,000원
        83.
        2011.05 구독 인증기관·개인회원 무료
        The Samia cynthia ricini (Lepidoptera: Saturniidae) is a commercial silk-producing insect belonging to an insect family Saturniidae in Bombycoidea. The species that has presumably been originated in India, is distributed in India, China, and Japan. Unlikely domestic silkworm the prime host plant for the species is a castor-oil plant (Ricinus communis in Euphorbiaceae). Recently, the eri-silkworm also is reared in Korea and is expected to be utilized for a diverse purpose. In this report, we present the complete mitochondrial genome of the species with the emphasis of a few major characteristics. The 15,384-bp long S. cynthia ricini (Lepidoptera: Saturniidae) mitochondrial genome was amplified into three long overlapping fragments (from COI ~ ND4, ND5 ~ lrRNA, and lrRNA ~ COI) and subsequent several short fragments using the long fragments as temperate. The primers for both long and short fragments were designed solely for lepidopteran genomes, without any species-specific primers. As a usual the genome is composed of 37 genes: 13 protein-coding genes (PCGs), two rRNA genes, and 22 tRNA genes, and one large non-coding region termed the A+T-rich region. Arrangement of the genome is identical to those of other lepidopteran mitochondrial genome, but this differs from the common arrangement found in a diverse insect order, by the movement of tRNAMet to a position 5’- up stream of tRNAIle. Unlikely previous report on the start codon for COI gene in Lepidoptera S. cynthia ricini COI gene starts with typical ATT codon located between tRNATyr and the beginning region of COI gene. The 22 tRNAs that are interspersed throughout the mitogenome ranged in length from 62 to 71 bp. All tRNAs but tRNASer(AGN) were shown to be folded into the expected cloverleaf secondary structures. More detailed structural and phylogenetic analyses among Bombycidae and Saturniidae in connection with other families in the Bombycoidea will be performed soon
        84.
        2010.12 구독 인증기관 무료, 개인회원 유료
        Influenza virus infection is a zoonosis that results in high mortality in animals and humans. Several recent avian influenza outbreaks have posed a significant public health threat to humans because there have been many cases of direct interspecies transmission from birds to humans. Influenza virus infection causes acute respiratory failure, which is the main cause of death, while chronic influenza virus infection in the central nervous system results in neural dysfunction. Of particular interest, according to one report, a group of patients who recovered from influenza virus infection during pandemics showed neuropsychiatric disorders, including depression, schizophrenia, and Parkinsonism. Thus, study of the etiology of neuropsychiatric disorders caused by influenza virus infection is needed. In order to conduct necessary experiments, it is essential to reproduce neurological phenomena that are manifested by human patients who have recovered from influenza virus infection using laboratory animals. In this review, we will discuss some of the facts that should be considered when establishing an animal model for study of central nervous system responses to influenza virus infection using mice.
        4,000원
        86.
        2010.05 구독 인증기관·개인회원 무료
        The phylogenetic relationships among true butterfly families (superfamily Papilionoidea) have been a matter of substantial controversy, and that debate has led to several competing hypotheses. Two of the most compelling of those hypotheses involve the relationships of (Nymphalidae + Lycaenidae) + (Pieridae + Papilionidae) and (((Nymphalidae + Lycaenidae) + Pieridae) + Papilionidae). In this study, approximately 3,500 nucleotide sequences from cytochrome oxidase subunit I (COI), 16S ribosomal RNA (16S rRNA), and elongation factor-1 alpha (EF-1α) were sequenced from 83 species belonging to four true butterfly families, along with those of eight outgroup species belonging to the skipper family (superfamily Hesperioidea). These sequences were subjected to phylogenetic reconstruction via Bayesian Inference (BI), Maximum Likelihood (ML), and Maximum Parsimony (MP) algorithms. All phylogenetic analyses among the four true butterfly families strongly indicated a sister relationship between the Nymphalidae and Lycaenidae on one hand, and relatively strongly indicated a sister relationship between the Pieridae and Papilionidae on another hand, thus supporting the hypothesis: (Nymphalidae + Lycaenidae) + (Pieridae + Papilionidae).
        87.
        2010.05 구독 인증기관·개인회원 무료
        The bumblebee, Bombus ignitus (Hymenoptera: Apidae), is a valuable natural resource that is one of the most notably utilized for greenhouse pollination in Korea. In order to understand the nature of genetic relationships, gene flow, and population structure of the species we sequenced a partial COI gene of mitochondrial DNA (mtDNA) corresponding to “animal barcode” region and the complete internal transcribed spacer 2 (ITS2) of the nuclear ribosomal DNA (nrDNA) collected from Korean localities. Although the 658-bp long mtDNA sequence provided only six haplotypes with the maximum sequence divergence of 0.61% (4 bp), the ITS sequences provided 84 sequence types with the maximum sequence divergence of 1.02% (21 sites), confirming better applicability of the ITS sequences to the study of intraspecific variation. The complete ITS2 sequences of B. ignitus were shown to be longest among known insects, ranging in size from 2,034 bp ~ 2,052 bp, harboring two duplicated repeats. Overall, a very high per generation migration ratio, a very low level of genetic fixation, and no discernable hierarchical population/ population group were noted to exist among populations of B. ignitus on the basis of both molecules, thus suggesting that the B. ignitus populations on the Korean peninsula are panmictic, which is consistent with our understanding of the dispersal capability of the species
        88.
        2010.05 구독 인증기관·개인회원 무료
        In an effort to gain a better understanding of the nature of the population genetic structure of the pest insect, Spodoptera litura (Lepidoptera: Noctuidae), tobacco cutworms were collected from six Korean and five Chinese localities and their mitochondrial A+T-rich region and nuclear internal transcribed spacer 2 (ITS2) regions were cloned and sequenced. A total of 106 A+T-rich region haplotypes and 92 ITS2 sequence types were obtained from 158 individuals. Compared to the preliminary mitochondrial COI gene sequence data that provided all identical sequence types in all samples, the A+T-rich region and nuclear ITS2 are highly variable. Overall, a low level of genetic fixation in the A+T-rich region (FST = 0 ~ 0.02965) and nuclear ITS2 (FST = 0 ~ 0.34491), and no discernable isolated population was noted to exist among most S. litura populations. The presence of a majority of within-population variations, rather than variations among populations or between China and Korea, indicates that the S. litura populations are composed of heterogeneous individuals. The fixation index at hierarchical level of among regions shows no significance, suggesting that the S. litura populations in both Korea and China are profoundly interrelated with one another. This finding is in accord with the current knowledge that S. litura has sufficient flight capacity for dispersal.
        89.
        2010.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The transcription factor nuclear factor-kB (NF-kB) plays an important role in regulating cell growth, apoptosis, and metastatic functions. Constitutive activation of NF-KB has been observed in various cancers; however, molecular mechanisms resulting in such activation remain elusive. Numerous evidences showed that over expression of TGase 2 might be linked with constitutive activation of NF-KB. To understand the pathways responsible for constitutive activation of NF-kB is important for rational design of NF-kB inhibitors for cancer therapy. Human salivary gland adenocarcinoma has been most aggressive solid tumors. Current therapy does not significantly improve survival rates. Thus, to investigate new therapeutic modalities against this adenocarcinoma is necessary. The purpose of this study was to study a constitutive activation of NF-kB with the expression of TG2 in SGT cell line origianted from human salivary gland adenocarcinoma by TGase 2 activity, RT-PCR and immunoslot blotting method. SGT cell line showed the highest TGase 2 activity and NF-kB activation than any other cell line. All the cell lines showed increased NF-kB mRNA activation after A231027 treatment than that of control. In immunoslot blotting, SGT cell line showed NF-kB activation correlated with TGase 2 expression after A231027 and BSA. It suggested that there might be a direct correlation between TGase 2 expression and NF-kB activation in SGT cell line.
        4,000원
        90.
        2009.05 구독 인증기관·개인회원 무료
        Root knot nematode species, such as Meloidogyne hapla, M. incognita, M. arenaria and M. javanica are economically most notorious nematode pests, causing serious damage to the various crops throughout world. In this study, DNA sequence analyses of the D1-D3 expansion segments of the 28S gene in the ribosomal DNA were conducted to characterize genetic variation of the four Meloidogyne species obtained from Korea and United States. PCR-RFLP (Polymerase Chain Reaction-Restriction Fragment Length Polymorphism), SCAR (Sequence Characterized Amplified Region) marker and RAPD (Random Amplification of Polymorphic DNA) also were used to develop the methods for exact and rapid species identification. In the sequence analysis of the D1-D3 expansion segments, only a few nucleotide sequence variation were detected among M. incognita, M. arenaria, and M. javanica, except for M. hapla. The PCR-RFLP analysis that involves amplification of the mitochondrial COII and lrRNA region yielded one distinct amplicon for M. hapla at 500 bp, enabling us to distinguish M. hapla from M. incognita, M. arenaria, M. javanica reproduced by obligate mitotic parthenogenesis. SCAR markers successfully identified the four root knot nematode species tested. We are under development of RAPD primers specific to the three root knot nematodes found in Korea.
        91.
        2009.05 구독 인증기관·개인회원 무료
        The 15,389-bp long complete mitogenome of the endangered red-spotted apollo butterfly, Parnassius bremeri (Lepidoptera: Papilionidae) was determined. This genome has a gene arrangement identical to those of all other sequenced lepidopteran insects, which have the gene order of tRNAMet, tRNAIle, and tRNAGln at the beginning. Due to the uncertainty the start codon for COI gene in insect has been discussed extensively. We propose the CGA sequence as the start codon for COI gene in lepidopteran insects, based on complete mitogenome sequences of lepidopteran insects including our P. bremerii and additional sequences of the COI start region from a diverse taxonomic range of lepidopteran species (a total of 51 species belonging to 15 families). As has been suggested in other sequenced lepidopteran insects the 18 bp-long poly-T stretch and the downstream conserved motif ATAGA that were previously suggested to serve as a structural signal for minor-strand mtDNA replication also was found at the 3’-end region of the P. bremerii A+T-rich region. In an extensive search to find out tRNA-like structure in the A+T-rich region, each one tRNATrp-like sequence and tRNALeu (UUR)-like sequence were found in the P. bremeri A+T-rich region, and most of other sequenced lepidopteran insects were shown to have tRNA-like structure within the A+T-rich region, thereby indicating that such feature is frequent in the lepidopteran A+T-rich region. Phylogenetic analysis using the concatenated 13 amino acid sequences and nucleotide sequences of PCGs of the four macrolepidopteran suferfamilies together with Tortricoidea and Pyraloidea well recovered a monophyly of Papilionoidea and a monophyly of Bombycoidea. However, Geometroidea and Noctuoidea were unexpectedly clustered as one group and placed this group to the sister group to Bombycoidea, instead of Papilionoidea in most analyses.
        92.
        2009.03 구독 인증기관 무료, 개인회원 유료
        This study was carried out to investigate effect of herbal extracts mixtures on hair growth in an alopecia model of C57BL/6 mice. There were 4 experimental groups including distilled water (DW, negative control), 25% ethanol(EtOH, vehicle control) and two herbal extract mixtures (HE-1 and HE-2). HE-1 included Polygonum and Brassica campestris extracts and HE-2 included Mulberry root and Gardenia extracts. The 6 weeks-old C57BL/6 male mice were shaved with an electric clipper and the test compounds were topically treated with 0.2 ml per mouse daily for 3 weeks. The hair re-growth was photographically determined at days 0, 4, 7, 10, 14, 17, and 21. The number of mast cells which is an important modulator of hair growth was counted in 1 cm of dorsal skin section of mice. There were no clinical signs in all experimental groups. As the results of photometric analysis, the topical application of the herbal extracts (HE-1 & 2) for 2 weeks to dorsal skin accelerated hair re-growth remarkably faster than that of DW group (p<0.05). Activity of alkaline phosphatase (ALP) was significantly increased in EtOH group compared to DW group (p<0.05). Both herbal extract mixtures also increased the ALP activity, but it was not significantly different from DW. Treatment of mice with HE-2 significantly increased mast cell population compared to EtOH. Taken together, these results suggest that herbal extract mixtures used in this study may have hair-growth promoting activities and can be useful for treatment for male pattern baldness or alopecia in humans.
        4,000원
        93.
        2009.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study investigated the effect of kilning condfition on the diastatic power and activities of protease, α-amylase, and β-amylase in rice malt. Common rice (Oryza sativa) was steeped at 30℃ for 50 h, germinated at 30℃ for 7 days, and kilned at 50℃ for 24 h. The moisture content and enzymatic activities were determined under various kilning times. As a result, the moisture content was reduced from 42.1 % to 3.9% after 24 h of kilning at 50℃. The protease activity of rice malt showed lower value than that of barley malt. All enzymatic activities were decreased during the kilning stage. Results indicated that after prolonged kilning at 50℃, the inactivation of hydrolytic enzymes might be occurred. Even though the amylolytic activity of malted rice showed low value, the rice malt shows the potential characteristics as ingredient for the brewing and cereal industries.
        4,000원
        94.
        2008.12 구독 인증기관 무료, 개인회원 유료
        Recently, increasing interests in local foods have been highlighted along with active efforts and activities from autonomy organizations to develop local cultures and promote local economies by generating value added products and profits through the development of local foods. Subsequently, useful effects might result by making local foods attractive to tourists, such as by using indigenous Gimpo products to makc menu items that incorporate the social, economic, and cultural aspects of the Gimpo area, and contributing to its food culture, the development and use of its indigenous products, and promoting local restaurant businesses, etc. The items of the Survey used to select the local food menu items to be developed were limited to ideas offered by expert groups, and were implemented by a new menu developmεnt process. In order to derive the menu items to develop, the following method was applied: a brainstorming session with experts to generate and draft ideas, a questionnaire to chefs and cooks in special grade hotels is Seoul to select thε menu items to develop from those drafted, and sensory evaluations by experts to evaluate the developed items. Frequency analysis and technical statistical analysis were performed using the SPSS 12.0 program package, where 13 kinds of local foods were ultimately developed using indigenous products of Gimpo. The developed local food menu items werε rice & grape sujaebi, grape sikhae, fried rice embryo bud, grape yanggaeng, rice pancakes, rice spaghetti, grape seed oil dressing, grape sauce, rice pizza, grape pie, rice & grape ice cream, grape chocolate, and rice roll cakes.
        4,000원
        95.
        2008.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The malting process of rice (OM4080 variety from Mekong Delta Rice Research Institute) was studied under pilot condition plan by means of the second-order experimental design. Processing parameters, such as the steeping time (0-60 hrs), steeping temperature (5-45℃), germination time (0-8 days), germination temperature (5-45℃) and gibberellin concentration (0-2 mg/kg) were investigated. As a result, all germination conditions, especially germination time, germination temperature, and gibberellin concentration had a significant effect on the malting loss, amylase activity and starch content. The protein content was not clearly affected by any conditions. The optimum conditions for malting process (with highest amylase activity) were as follows: 30 hrs of steeping time, 30-35℃ of steeping temperature, 5-5.5 days of germination time, 25℃ of germination temperature, and 1.5 mg/kg of giberrellin concentration.
        4,000원
        96.
        2008.05 구독 인증기관·개인회원 무료
        We determined the complete mitochondrial genome (mitogenome) of the jewel beetle, Chrysochroa fulgidissima (Coleoptera: Buprestidae) from two overlapping fragments and subsequent sub fragments. The 15,592-bp long C. fulgidissima mitogenome contains gene arrangement and content identical to the most common arrangement found in insects. Most individual C. fulgidissima mitochondrial (mt) genes were well within the range found in the respective genes of other insects. The 875-bp A+T-rich region is shortest among the coleopteran mitogenomes sequenced in their entirety. The region is interesting in that it contains several stem-and-loop structures and tRNA-like structure found in the A+T-rich regions of other insect mitogenomes. As seen in other insect motogenomes the start codon of C. fulgidissima COI gene also is unusual because no typical start codon is available. Three of the 13 protein-coding genes have incomplete termination codon T or TA. All tRNA formed stable stem-and-loop structure, except for tRNASer(AGN), the DHU arm of which formed a simple loop as seen in many other metazoan mt tRNASer(AGN).
        97.
        2007.04 KCI 등재 구독 인증기관·개인회원 무료
        Sulfur is commonly used in Asia as an herbal medicine to treat inflammation and cancer , a nd potent chemo preventi ve effects have been demons tra ted in various in vivo and in vitromodels for s ul fur-containing compounds found in natura l1y occurring product s. Here, we 1'eport the growth inhibitory and apoptosis-related effects of a n ewly developedhigh-puri ty edible sulfur(ES) on immo1'tali zed human o1'al ke1'atinocytes(IHOKs) and on oral cancer cells representing two stages of oral cancer (HN4‘ HN12) based on an 3-(4,5-Dimethylthiazol-2-yl) -2.5- diphe n yltetrazolium bromide(MTI) assay, Western blotting, cell cycle analysis, and nuclear staining. The puri ty of the ES used in thi s study was ve1'ified by high performance liquid chromatog1'aphy (HPLC) , ami no acid analysis and energy dispersive spectroscopy(EDS). ES inhibited the prolife1'ation of imrnortalized and ma lig nant o1'al kerati nocytes in a dose- and time-dependent manne1' FITC-Annex.in V staining, DNA fragmentation t esting. and Hoechst 33258 s taining revealed that ES inhibits cell growth via apoptosis. ES bl ocked cell-cycle prog1'ession at t he sub-Gl phase‘ wi th decreased expression of cyclins Dl, D2‘ and E, and their activating partn ers cdk2‘ cdk4‘ and cdkfì, and a concomitant induction of p53 and p21/WAF1. Furthe1'more, ES treatment in creased the cytosolic level of cytochrome c and resulted in caspase- 3 activation‘ and thi s effect was co1'1'elated with Bax up-regulation and Bcl-2 down-1'egulation Taken together‘ these data suggest that ES is a potential chemopreventive and chemotherapeut ic agent fo r oral ca ncer
        98.
        2004.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Highly ordered pure-silica MCM-41 materials possessing well-defined morphology have been successfully prepared with surfactant used as a template. The fabrication of mesoporous silica has received considerable attention due to the need to develop more efficient materials' for catalysis, separations, and chemical sensing. The surface modified MCM-41 was used as anadsorbent for biomolecules. Silica-supported organic groups and DNA adsorption on surface modified MCM-41 were investigated by FT-IR and UV-Vis spectrometer, respectively. The use of MCM-41 as the modification of electrode surfaces were investigated electrochemical properties of metal mediators with biomolecules. The modified ITO electrodes increased peak currents for a redox process of [Ru(bpy)3]2+ relative to the bare electrode. The electrochemical detection of DNA by cyclic voltammetry when the current is saturated in the presence of the mediator appeared more sensitive due to a higher catalytic current on the MCM-41 supported electrodes modified by carboxylic acid functional groups. The carboxyl or amine groups on the surface of MCM-41 interact and react with the -NH2 groups of guanine and backbone, respectively. Highly ordered mesoporous materials with organic groups could find applications as DNA sensors.
        4,000원
        99.
        2002.10 구독 인증기관 무료, 개인회원 유료
        The main objective of this paper to purpose a evaluating methods of process capability measures for exponential distributed quality characteristics. For correctly evaluating process capability , the first thing , exponential data is applied the Lilliefors test statistic to the null hypothesis of nornality. The next , exponential parameters is estimated in terms of MLE , ME , MME and then evaluated , respectively , process capability index based on exponential curved (Cpe). We consider simultaneously process capability messures based on Pearson system, Johnson system and Burr system.
        4,000원
        100.
        2001.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        We have studied the nonlinear evolution of a magnetized disk of isothermal gas, which is sustained by its self-gravity. Our objective is to investigate how the Jeans, Parker, and convective instabilities compete with each other in structuring/de-structuring large scale condensations in such disk. The Poisson equation for the self-gravity has been solved with a fourth-order accurate Fourier method along with the Green function, and the MHD part has been handled by an isothermal TVD code. When large wavelength perturbations are applied, the combined action of the Jeans and Parker instabilities suppresses the development of the convection and forms a dense core of prolate shape in the mid-plane. Peripheral structures around it are filamentary. The low density filaments connect the dense core to the diffuse upper region. On the other hand, when small wavelength perturbations are applied, the disk develops into an equilibrium state which is reminiscent of the Mouschovias's 2-D non-linear equilibrium of the classical Parker instability under an externally given gravity.
        3,000원
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