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        검색결과 38

        21.
        2008.06 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        As a continuation of a previous work by Park et al. (2006), we have developed a two-element radio interferometer that can measure both the phase and amplitude of a visibility function. Two small radio telescopes with diameters of 2.3 m are used as before, but this time an external reference oscillator is shared by the two telescopes so that the local oscillator frequencies are identical. We do not use a hardware correlator; instead we record signals from the two telescopes onto a PC and then perform software correlation. Complex visibilities are obtained toward the sun at λ=21cm for 24 baselines with the use of the earth rotation and positional changes of one element, where the maximum baseline length projected onto UV plane is ~90λ As expected, the visibility amplitude decreases with the baseline length, while the phase is almost constant. The image obtained by the Fourier transformation of the visibility function nicely delineates the sun, which is barely resolved due to the limited baseline length. The experiment demonstrates that this system can be used as a "toy" interferometer at least for the education of (under)graduate students.
        4,000원
        22.
        2008.02 구독 인증기관 무료, 개인회원 유료
        This paper describes the traditional Ondol medical care, the specific combination of ancient and contemporary examples to be articulated. As a traditional Korean culture, to be extracted from the historical perspective, it described the relationship and origins between them, From a health perspective, in accordance with the logic and pharmacologyit introduced Ondol as the important principle of health care equipment. The modern architecture of some common harmful to the body, from the perspective of Ondol, it should be improved and based on scientific proof to the theory.
        4,000원
        23.
        2020.06 KCI 등재 서비스 종료(열람 제한)
        Alcoholic fatty liver disorder has become a frequent health concern worldwide. To investigate the effects of Brassica oleracea (B. oleracea) sprout extract (BOE), the present study was designed with alcoholic fatty liver in the rat. Initially, the effects of BOE on liver parameters were examined. Male rats were divided into five groups. The normal control group was fed the normal diet, and the BOE group was fed the high fat diet and ethanol with/without BOE for 4 weeks. After 4 weeks feeding period, rats were sacrificed and their livers and blood were used for fatty liver-related biomarkers analyses. As a result, BOE ameliorated fatty liver-related enzymes profiles in liver tissues and also reduced blood alcohol concentration in rat model. We demonstrated that BOE protected the high fat diet and alcohol-induced fatty liver in rat model. Furthermore, BOE increased detoxificative abilities against alcohol.
        24.
        2018.06 KCI 등재 서비스 종료(열람 제한)
        In this study, we investigated the effect of the extracts from Vaccinium oldhamii on cell proliferation and the regulatory mechanisms of cyclin D1 protein level in human cancer cells. The branch extracts from Vaccinium oldhamii (VOB) showed higher inhibitor effect against the cell growth than leave extracts (VOL) and fruit extracts (VOF) in human colorectal cancer, breast cancer, prostate cancer, non-small lung cancer, pancreatic cancer and liver cancer cells. In addition, VOB decreased cyclin D1 level at both protein and mRNA level. MG132 treatment attenuated VOB-mediated cyclin D1 downregulation. A point mutation of threonine-286 to alanine attenuated cyclin D1 degradation by VOB. In addition, the inhibition of nuclear export by leptomycin B (LMB) attenuated cyclin D1 degradation by VOB. But, the treatment of PD98059 (ERK1/2 inhibitor), SB203580 (p38 inhibitor), SP600125 (JNK inhibitor), LiCl (GSK3β inhibitor), LY294002 (PI3K inhibitor) or BAY 11-7082 (IκK inhibitor) did not affect VOB-induced cyclin D1 degradation. In conclusion, VOB induced cyclin D1 degradation through redistribution of cyclin D1 from the nucleus to cytoplasm via T286 phosphorylation of cyclin D1, which resulted in the inhibition of cancer cell proliferation.
        25.
        2017.12 KCI 등재 서비스 종료(열람 제한)
        In this study, we elucidated anti-cancer activity and potential molecular mechanism of 70% ethanol extracts from Taxilli Ramulus (Taxillus chinensis (DC.) Danser) (TR-E70) against human colorectal cancer cells. Anti-cell proliferative effect of TR-E70 was evaluated by MTT assay. The effect of TR-E70 on the expression of cyclin D1 in the protein and mRNA level was evaluated by Western blot and RT-PCR, respectively. TR-E70 suppressed the proliferation of human colorectal cancer cell lines, HCT116 and SW480. Although TR-E70 decreased cyclin D1 expression in protein and mRNA level, decreased level of cyclin D1 protein by TR-E70 more dramatically occurred than that of cyclin D1 mRNA. Cyclin D1 downregulation by TR-E70 was attenuated in presence of MG132. In addition, TR-E70 phosphorylated threonine-286 (T286) of cyclin D1. TR-E70-mediated cyclin D1 degradation was blocked in presence of LiCl as an inhibitor GSK3β but not PD98059 as an ERK1/2 inhibitor and SB203580 as a p38 inhibitor. Our results suggest that TR-E70 may downregulate cyclin D1 as one of the potential anti-cancer targets through GSK3β-dependent cyclin D1 degradation. From these findings, TR-E70 has potential to be a candidate for the development of chemoprevention or therapeutic agents for human colorectal cancer.
        26.
        2017.05 서비스 종료(열람 제한)
        Background : Although ginseng has various bioactive compounds in it, there is lack of study on the variations of bioactive compounds in ginseng according to the cultivation soil and the applied fertilizer types (or amount). Therefore, this study aims to examine the variations of 37 fatty acids (FA) and 8 vitamin E (Vit-E) vitamers in 6-year-old ginseng root cultivated in different soil types with different fertilizers regimes. Methods and Results : The profiling of 37 FAs and 8 Vit-E vitamers in 6-year-old ginseng roots was measured by gas chromatography coupled with a flame ionization detector, and then these results were statistically analyzed with chemometrics. The FA and Vit-E content in ginseng roots varied significantly with respect to soil cultivation conditions due to organic fertilizer types and amounts used. Unsaturated FA in ginseng is approximately 2.7 fold higher than the saturated FA. Linoleic, palmitic, and oleic acids were the most abundant FAs found in the ginseng roots. Also, the major Vit-E vitamer found in ginseng root is α-tocopherol. In particular, the application of rice straw compost or food waste fertilizer was increased to create nutritionally desirable FAs and bioactive Vit-E in ginseng root. In addition, phytonutrient profiling coupled with chemometrics can be used to discriminate the cultivation conditions of ginseng. Conclusion : This study extends our understanding about the variations of FA and Vit-E in ginseng root depending on cultivation conditions. Hence, these results can be useful as basic information for reliable ginseng production containing high amounts of phytonutrients in a paddy-converted field.
        27.
        2017.05 서비스 종료(열람 제한)
        Background : The geographical origin of Panax ginseng Meyer, a valuable medicinal plant, is important to both ginseng producers and consumers in the context of economic profit and human health benefits. We therefore aimed to discriminate between the cultivation regions of ginseng using the stable isotope ratios of C, N, O, and S, which are abundant bio-elements in living organisms. Methods and Results : The C, N, O, and S stable isotope ratios were measured by isotope ratio mass spectrometer, and then these isotope ratios profiling was statistically analyzed with chemometrics. The various isotope ratios found in Panax ginseng roots were significantly influenced by region, cultivar, and the interactions between these two factors (P ≤ 0.0002). In particular, δ18O was lower in ginseng roots grown at high altitudes (r = −0.47), while δ34S was higher in ginseng roots grown close to coastal areas (r = −0.48). Chemometric results provided discrimination between the majorities of different cultivation regions. Conclusion : Our case study extends the understanding about the variation of C, N, O, and S stable isotope ratios in ginseng root depending on cultivation region. Hence, the analysis of stable isotope ratios is a suitable tool for discrimination between the regional origins of ginseng samples from Korea, with potential application to other countries.
        28.
        2017.05 서비스 종료(열람 제한)
        Background : Corrosion is one of the most devastating problems faced by most industries. Mild steel has played a vital role in various fields due to the excellent mechanical properties of mild steel such as low density, high strength-to-weight ratios, good environmental stability, high thermal conductivity, and corrosion resistance. Methods and Results : The total phenolic contents (TPC) and total flavonoid contents (TFC) of the methanolic extract of C. grandiflora and R. verniciflua leaf have been examined, and its corrosion inhibition performance was investigated by weight loss and electrochemical impedance spectroscopy (EIS) and polarization measurements. The surface morphology of mild steel was analyzed by scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDX) and by atomic force microscopy (AFM). The percentage composition of polyphenolic compounds was found to be higher in C. grandiflora and R. verniciflua plant extracts, and it was proved to be a superior, eco-friendly, and anti-corrosive inhibitor for mild steel in 1M of H2SO4. The Tafel polarization studies indicate that the plant extract is a mixed-type inhibitor. Scanning electron microscopy/energy -dispersive X-ray spectroscopy (SEM-EDS), and atomic force microscopy (AFM) studies confirmed the formation of a protective film on the metal surface. The corrosion inhibition of the C. grandiflora and R. verniciflua plant extracts was characterized by Fourier transform infrared (FT-IR), UV-visible spectra, and wide-angle X-ray diffraction (XRD) studies; these show the strong interaction between the metal surface and the inhibitor. Conclusion : The methanolic extract was prepared the two different plants like C. grandiflora, and R. verniciflua was studied the corrosion inhibition on the mild steel specimen in acidic medium through various methods involving weight loss measurements, EIS, and potentiodynamic polarization. The results shows that the C. grandiflora, and R. verniciflua plant extracts illustrate an effective corrosion inhibitor for mild steel with good anticorrosion properties in acidic environmen
        29.
        2016.05 서비스 종료(열람 제한)
        Background : Cordyceps militaris has been an wonder drug to anti-aging efficacy and called the three main drugs with ginseng and deer antler from the past. Cordycepin, cordycepic acid (d-mannitol) and adenosine are known as functional ingredients in Cordyceps militaris. Among them, cordycepin, the representative component, has been reported as antimicrobial substance containing immune enhancement, anti-cancer and anti-inflammatory effects. Methods and Results : After Cordyceps militaris produced from different types of medium mixed with 10-fold volume of purified water, the mixture were extracted at 70±5℃ for a hour and that extracts re-extracted using ultrasonics wave for 30 minutes. Qualitative analysis of the index component was determined by using the Q-TOF (A quadrupole time-of-flight mass spectrometer), and quantitative analysis was performed by using HPLC (high-performance liquid chromatography) with Xselect HSS T3 column (2.1 X 100 mm, 2.5㎛, Waters, USA) and ultrapure water and acetonitrile as mobile phase A and B. Detection column temperature, injection volume and the flow rate were 35℃, 2 μL and 0.3 mL / minute respectively. The cordycepin content of Cordyceps militaris produced from medium mixed with vegetable and animal ingredients higher than single ingredient. Moreover, through a variety of analyzes by varying the type and content of the medium additives, the cordycepin in Cordyceps militaris produced from medium mixed with animal ingredients highest. Furthermore, the cordycepin content of a fruit body was higher than those of the a mycelium. Conclusion : These results provide a method for producing an high cordycepin content of Cordyceps militaris as functional food ingredient.
        30.
        2016.03 KCI 등재 서비스 종료(열람 제한)
        This study was conducted to develop a fast and efficient screening method to determine the quantity of fatty acid in peanut oil for high oleate breeding program. A total of 329 peanut samples were used in this study, 227 of which were considered in the calibration equation development and 102 were utilized for validation, using near infrared reflectance spectroscopy (NIRS). The NIRS equations for all the seven fatty acids had low standard error of calibration (SEC) values, while high R2 values of 0.983 and 0.991 were obtained for oleic and linoleic acids, respectively in the calibration equation. Furthermore, the predicted means of the two main fatty acids in the calibration equation were very similar to the means based on gas chromatography (GC) analysis, ranging from 36.7 to 77.1% for oleic acid and 7.1 to 42.7% for linoleic acid. Based on the standard error of prediction (SEP), bias values, and R 2 statistics, the NIRS fatty acid equations were accurately predicted the concentrations of oleic and linoleic acids of the validation sample set. These results suggest that NIRS equations of oleic and linoleic acid can be used as a rapid mass screening method for fatty acid content analysis in peanut breeding program.
        31.
        2015.07 서비스 종료(열람 제한)
        Seed color is an important factor affecting physiological and developmental process in wheat. One of the plant pigments, anthocyanins are a group of flavonoid compounds well known as pigments responsible for blue, purple, red, or yellow coloration of plant tissues. In this study, we investigated the pigmentation of purple and yellow color seed according to wheat grain developmental stages. The contents of anthocyanin and chlorophyll in the purple and yellow seeds were measured. Chlorophyll contents were changed similarly in both purple and yellow color seed, and no significant difference was observed between them. In purple color seed, the content of anthocyanin was significantly induced compared with yellow color seed. The individual anthocyanin components were investigated by ultra performance liquid chromatography (UPLC). Cyanidine-3-glucoside (C3G) and peonidine-3-glucoside (P3G) were detected as predominant anthocyanin in purple color wheat. To investigate whether structural genes in anthocyanin biosynthesis were involved in the trait differences between purple and yellow color seed, we examined the expression of anthocyanin biosynthesis-related genes (CHS, CHI, F3H, DFR, ANS, UFGT) and MYB transcription factor in developing wheat grains by using qRT-PCR. This study indicates that the expression of anthocyanin biosynthesis-related genes and MYB transcription factors correlate with anthocyanin levels of grain.
        32.
        2015.06 KCI 등재 서비스 종료(열람 제한)
        The flower buds of Sophora japonica L (SF), as a well-known traditional Chinese medicinal herb, have been used to treat bleeding-related disorders such as hematochezia, hemorrhoidal bleeding, dysfunctional uterine bleeding, and diarrhea. However, no specific anti-cancer effect and its molecular mechanism of SF have been described. Thus, we performed in vitro study to investigate if treatment of SF affects activating transcription factor 3 (ATF3) expression and ATF3-mediated apoptosis in human colorectal cancer cells. The effects of SF on cell viability and apoptosis were measured by MTT assay and Western blot analysis against cleaved poly (ADP-ribose) polymerase (PARP). ATF3 activation induced by SF was evaluated using Western blot analysis, RT-PCR and ATF3 promoter assay. SF treatment caused decrease of cell viability and increase of apoptosis in a dose-dependent manner in HCT116 and SW480 cells. Exposure of SF activated the levels of ATF3 protein and mRNA via transcriptional regulation in HCT116 and SW480 cells. Inhibition of extracellular signal-regulated kinases (ERK) 1/2 by PD98059 and p38 by SB203580 attenuated SF-induced ATF3 expression and transcriptional activation. Ectopic ATF3 overexpression accelerated SF-induced cleavage of PARP. These findings suggest that SF-mediated apoptosis may be the result of ATF3 expression through ERK1/2 and p38-mediated transcriptional activation.
        33.
        2014.07 서비스 종료(열람 제한)
        Gamma irradiation has been used as a tool for plant mutation breeding to select new cultivar with improved characteristics. Generally, the irradiation of seeds with high doses of gamma rays disturbs the synthesis of protein, hormone balance, and enzyme activity. And also, high dose of gamma rays to reduce plant height, number of tiller, and root length, although the effect of gamma-irradiated plants may depend on the species and cultivar or stress conditions. Biological effects of radiations can be divided into two types according to dose range and periods of exposure. Acute irradiation represents exposure to high-dose of irradiation over short period time, whereas the chronic irradiation is comprised of exposure to low doses of radiation over extended period of time. To compare the effects of acute and chronic exposure to ionizing radiation on two wheat cultivars (K4191 and Geumgangmil), we measured their germination rate, seedling height, and root length. In order to understand the influence of antioxidant-related genes and DNA repair-related genes, we used qRT-PCR methods to identify their expression levels. To study the behavior of a radiation-induced free radical, gamma-irradiated seeds were used for ESR spectroscopy. Plant growth pattern was showed positive correlation with ESR results. This study indicates that low level chronic radiation exposure is even more serious effects than short doses of high level radiation according to different wheat cultivar.
        34.
        2014.07 서비스 종료(열람 제한)
        Acanthopanax species is known commonly as Siberian ginseng, touch-me-not, devil’s shrub, prickly eleutherococc, eleutherococc and wild pepper. A diverse group of chemical compounds isolated from Acanthopanax species was named ‘eleutherosides’. Among eleutherosides, eleutherosides B and E were widely known in Acanthopanax species. Acanthopanax species are cultivated and grow wild in a various area of Korea and have a variety of pharmacological effects. But, there are a lot of difficulties on producing excellent Acanthopanax species, according to the cultivated method is different pharmacological ingredients. This study, therefore, analyzed eleutherosides B and E in A. divaricatus and A. koreanum by different fertilizer ratio using HPLC. We will be investigated a high content of eleutherosides B and E by different fertilizer ratio and suggest an efficient fertilizer ratio of A. divaticatus and A. koreanum. All samples of A. divaricatus and A. koreanum were collected at Yeongcheon Agricultural Technology & Extension Center, Yeongcheon, Korea. The sample was prepared by upper and lower parts. The fertilizer ratio are N-P-K(10.5-8.5-8.5: 50 kg/10a), 2N-P-K (21-8.5-8.5: 50 kg/10a), N-2P-K (10.5-17-8.5: 50 kg/10a), N-P-2K (10.5-8.5-17: 50 kg/10a), and 2N-2P-2K (21-17-17: 50 kg/10a), respectively. To analyze eleutherosides B and E, 5 g of A. divaricatus and A. koreanum was extracted with 50% MeOH (3 × 100 ml) by reflux and evaporated in vacuo. The residue was dissolved in 1 ml of MeOH. The resulting solution was used for HPLC analysis. HPLC separation of eleutherosides B and E for qualitative and quantitative analysis was performed using a reverse phase system. A Discovery®C18 (4.6 × 250 mm, 5 μm) column was used with a mobile phase that consisted of water and acetonitrile. A gradient solvent system of water and acetonitrile (90:10 to 70:30 for 20 min) was used for the elution program. UV detection was conducted at 350 nm. The injection volume was 10 μl and the flow rate was 1 ml/min. All injections were performed in triplicate. The different fertilizer ratio yielded total eleutherosides B and E contents of 4.417-6.905 and 3.652-7.227 mg/g in the upper and lower parts of A. divaricatus, respectively. In A. koreanum, the total eleutherosides B and E contents were 4.591-10.108 and 3.834-9.079 mg/g in the upper and lower parts, respectively. The best conditions to increase eleutherosides B and E content in A. divaricatus was determined to be with N-2P-K fertilizer ratio, on the other hand, in A. koreanum was 2N-2P-2K fertilizer ratio.
        35.
        2010.04 KCI 등재 서비스 종료(열람 제한)
        UNUSUAL FLORAL ORGAN (UFO), a novel gene, is involved in controlling flowering initiation and development. In Arabidopsis, UFO is required for floral organ identity in the second and third whorls. However, the mode of expression and function of TaUFO have not been studied yet. The cDNA sequence of TaUFO is comprised of 1344 bp open reading frame which encodes 50.82 KDa polypeptide consisting amino acid residues. F-box protein, the components of TaUFO, plays an important regulatory role in a wide diversity of developmental and physiological responses. In almost all F box proteins, the N terminus of the protein contains the F-box motif, and the rest of the protein contains the protein-protein interaction domains required for target protein binding. In order to elucidate the function of the TaUFO, various phytohormones and abiotic stresses were applied on young seedlings (14 day after germination) and its transcripts were evaluated. TaUFO:GFP fusion construct was transformed into onion epidermal cells by particle bombardment to elucidate the subcellular localization of the TaUFO protein. The function of the F-box protein is to interact with target proteins. With the use of a yeast two-hybrid screen to isolate proteins interacting with the TaUFO (F box protein), we identified potential TaUFO interactive protein in wheat spikelet library.
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