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        검색결과 201

        61.
        2008.12 구독 인증기관 무료, 개인회원 유료
        Bicuculline is one of the most commonly used GABAд eceptor antagonists in electrophysiological research. Because of its poor water solubility, bicuculline quaternary ammonium salts such as bicuculline methiodide (BMI) and bicuculline methbromide are preferred. However, a number of studies have shown that BMI has non-GABAд eceptor-mediated effects. The substantia gelatinosa (SG) of the trigeminal subnucleus caudalis (Vc) is implicated in the processing of nociceptive signaling. In this study, we investigated whether BMI has non-GABA receptor-mediated activity in Vc SG neurons using a whole cell patch clamp technique. SG neurons were depolarized by application of BMI (20M) using a high Cℓ⁻ipette solution. GABA ( 30-100μM) also induced membrane depolarization of SG neuron. Although BMI is known to be a GABAд receptor antagonist, GABA-induced membrane depolarization was enhanced by co-application with BMI. However, free base bicuculline (fBIC) and picrotoxin (PTX), a GABAд and GABAс receptor antagonist, blocked the GABA-induced response. Furthermore, BMI-induced membrane depolarization persisted in the presence of PTX or an antagonist cocktail consisting of tetrodotoxin (Nα+ nnel blocker),AP-5 (NMDA receptor antagonist), CNQX (non-NMDA receptor antagonist), and strychnine (glycine receptor antagonist). Thus BMI induces membrane depolarization by directly acting on postsynaptic Vc SG neurons in a manner which is independent of GABAд receptors. These results suggest that other unknown mechanisms may be involved in BMI-induced membrane depolarization.
        4,000원
        62.
        2008.10 구독 인증기관·개인회원 무료
        The 15,338-bp long complete mitochondrial genome (mitogenome) of the Japanese oak silkmoth, Antheraeayamamai (Lepidoptera: Saturniidae) was determined. This genome has a gene arrangement identical to those of all other sequenced lepidopteran insects, but differs from the most common type, as the result of the movement of tRNAMet to a position 5’-upstream of tRNAIle. No typical start codon of the A. yamamai COI gene is available. Instead, a tetranucleotide, TTAG, which is found at the beginning context of all sequenced lepidopteran insects was tentatively designated as the start codon for A. yamamai COI gene. Three of the 13 protein-coding genes (PCGs) harbor the incomplete termination codon, T or TA. All tRNAs formed stable stem-and-loop structures, with the exception of tRNASer(AGN), the DHU arm of which formed a simple loop as has been observed in many other metazoan mt tRNASer(AGN). The 334-bp long A+T-rich region is noteworthy in that it harbors tRNA-likestructures, as has also been seen in the A+T-rich regions of other insect mitogenomes. Phylogenetic analyses of the available species of Bombycoidea, Pyraloidea, and Tortricidea bolstered the current morphology-based hypothesis that Bombycoidea and Pyraloidea are monophyletic (Obtectomera). As has been previously suggested, Bombycidae (Bombyxmori and B.mandarina) and Saturniidae (A.yamamai and Caligula boisduvalii) formed a reciprocal monophyletic group.
        64.
        2007.12 구독 인증기관 무료, 개인회원 유료
        This study was conducted to examine the mRNA expression of apoptosis-related and imprinted genes and methylation pattern of the differentially methylated region (DMR) of H19 gene in day 35 of SCNT pig fetuses. The day 35 of natural mating (control) or cloned (clone) pig fetuses were recovered from uterus. Endometrium from dam and liver from fetus were obtained, respectively. mRNA expression was evaluated by real-time PCR and methylation pattern was analyzed by bisulfite sequencing method. The Bcl-2 mRNA expression in clone was significantly lower than that of control (p<0.05). The mRNA expression of H19 gene in both endometrium and liver was significantly higher in clone than that of control, respectively (p<0.05). The level of IGF-2 mRNA in liver of clone was significantly lower than that of control (p<0.05), whereas the mRNA expression of IGF2-R gene in liver of clone was significantly higher than that of control (p<0.05). The DMR of H19 was lower methylation pattern in clone than that of control. These results suggest that the aberrant mRNA expression of apoptosis-related and imprinted genes and the lower DMR methylation pattern of imprinted gene may be closely related to the inadequate fetal development of cloned fetus.
        4,000원
        66.
        2004.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 준 회분식 교반조를 사용하여 polybutene (PB)와 polyisobutylene (PIB)고분자를 용해한 벤젠 용액을 연속상, 물을 불연속상으로 구성한 w/o 에멀션액막에 CO2을 흡수시켜 흡수속도를 측정하였다. 점탄성을 나타내는 Deborah 수를 사용하여 점탄성 비뉴튼액체에서 구한 부피물질전달계수 (kLa)를 고찰하고, 수용액에 첨가한 2-amino-2-methyl-1-propanol(AMP)와 CO2의 반응 메카니즘을 해석하였다.
        4,600원
        68.
        2003.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Presbyope has not clear vision with elderly changes. To introduce the essential preliminary examination for presbyope, we performed preliminary tests in 190 elderly patients with case history, slitlamp examination, pinhole test, Hirschberg test, pursuit, stereopsis, pupil reaction, Worth-4 dot test, Amsler grid test, dominant eye test. To perform an examination, the case history is clitical as it guides the whole examination. Chief complaints were epiphora, decreased visual acuity, floaters, hyperemia, eye pain, etc. From the information gained in the case history, we deduced a list of tentative diagnosis. Throughout the examination we decided whether additional tests. The 18.9% of patients didn't have improve visual acuity in pinhole test. Cause of reduced visual acuity in pinhole test was opaque of refractive media such as cataract or pterygium. In 44.7% of patients, stereoauity falls below 40s of arc. The 6.8% of patients have suppression of right or left eye. The 28.9% of patients have metamorphopsia or scotomas in Amsler chart test. Therefore, pinhole visual acuity helps to differentiate ocular pathology from lack of refractive media clarity. Amsler chart is also useful for monitoring age related maculopathy. We suggest that Jones dye test for tear drainage, pinhole test, Amsler grid test and Worth-4 dot test are essential for presbyope.
        4,000원
        71.
        2019.01 KCI 등재 서비스 종료(열람 제한)
        본 연구에서는 비슬산 이중편파 Radar 자료와, GPM 위성자료 및 21개 (Korea Meteorological Administration, KMA) 지상강우자료를 활용하여 분포형 강우-유출 모형(KIneMatic wave STOrm Runoff Model2, KIMSTORM2)을 이용해 남강댐 유역(2,293 km2)을 대상으로 유출해석을 수행 하였다. 모형의 유출 해석은 2016년 10월 5일 02:00∼09:00 총 8시간 동안 최대강우강도 33 mm/hr, 유역평균 총 강우량 82 mm이 발생한 태풍 차 바(CHABA)를 대상으로 하였으며, Radar 및 GPM 자료와 조건부합성(Conditional Merging, CM) 기법을 적용한 Radar (CM-corrected Radar) 및 GPM (CM-corrected GPM) 자료를 각각 활용하여 결과를 비교하였다. 이 때, 공간 강우자료에 유출 검보정은 남강댐 유역 내 3개의 수위관측 지점(산청, 창촌, 남강댐)을 대상으로 실시하였으며, 모형의 매개변수 초기토양수분함량, 지표와 하천의 Manning 조도계수를 이용하여 검보정하였다. 유출 결과는 결정계수(Determination coefficient, R2), Nash-Sutcliffe의 모형효율계수(NSE) 및 유출용적지수(Volume Conservation Index, VCI)를 산정하였다. 그 결과 CM-corrected Radar, GPM 자료가 평균 R2는 0.96, NSE의 경우 0.96, 유출용적지수(VCI)는 1.03으로 가장 우수한 결과를 나타내었다. 최종적으로 CM 기법을 이용한 보정된 공간분포자료는 기존의 자료에 비해 시공간적으로 정확한 홍수 예측에 사용 될 것으로 판단된다.
        72.
        2018.09 KCI 등재 서비스 종료(열람 제한)
        본 연구는 다목적함수를 고려한 입자군집최적화(Particle Swarm Optimization, PSO) 알고리즘을 Python으로 개발하고, Soil and Water Assessment Tool (SWAT) 모형에 적용하여 자동보정 알고리즘의 적용 가능성을 평가하였다. SWAT 모형의 유출 해석은 안성천의 공도 수위 관측소 상류유역(364.8 km2)을 대상으로 하였으며, 공도 지점의 2000년부터 2015년까지의 일 유량 자료를 이용하였다. PSO 자동보정은 결정계수 (coefficient of determination, R2), 평균제곱근오차(RMSE), NSE 모형효율계수(Nash-Sutcliffe Efficiency, NSEQ), 특히 중간유출과 기저유출의 보정을 위해 NSEINQ (Inverse Q)를 활용하여 SWAT을 보정하였다. PSO을 통한 SWAT 모형의 자동보정과 수동보정의 유출해석 결과, 각각 R2 는 0.64, 0.55, RMSE는 0.59, 0.58, NSEQ는 0.78, 0.75, NSEINQ는 0.45, 0.09의 상관성 분석결과를 보였다. PSO 자동보정 알고리즘은 수동보정에 비하여 높은 향상을 보였는데 특히 유출의 감수곡선을 개선시켰으며 적절한 매개변수 추가(RCHRG_DP)와 매개변수 범위의 설정으로 수동 보정의 한계를 보완하였다.
        73.
        2018.02 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        In this study, we evaluated the antioxidant activity and anti-inflammatory effects of Abeliophyllum distichum (A. distichum) leaves that were prepared via air-drying. Fresh and air-dried A. distichum leaves were examined via 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging assay and measurements of the reducing power. The suppression effects on inflammation of the leaves were analyzed by a western blot and RT-PCR on LPS-induced RAW 264.7 cells. As a result, the antioxidant activity of the fresh leaves was found to be more effective than that of the air-dried leaves. Also, the fresh leaves were more effective in suppressing the protein and mRNA levels of iNOS and COX-2 than the air-dried leaves, thereby indicating the better anti-inflammatory effects. In addition, the contents of phenolic compounds and acteoside were analyzed by high-performance liquid chromatography (HPLC). The results showed that the acteoside content decreased with the use of the air-drying method, while there was no change in the content of phenolic compounds. Therefore, this study indicated that fresh A. distichum leaves potential antioxidant and suppression activities of various factors that are involved in the production of NO, which were found to be better than those of air-dried A. distichum leaves. These biological activities were also found to be independent of the content of phonolic compounds and were assumed to be directly or indirectly related to the content of acteoside.
        74.
        2017.12 KCI 등재 서비스 종료(열람 제한)
        This study was conducted to investigate egg development and larvae morphological development of catfish and to provide basic data to clarify the genetic relationship with Siluriformes fish. The mother fish that was used in this study was caught in the stream of Nakdong River in Uiseong-gun, Gyeongbuk. The temperature range of the breeding was 23.0- 25.0℃ (mean 24.0±1.0℃) and egg size was 1.62-1.70 mm (mean 1.66±0.05, n=30). Eggs of catfish began hatching at 54 hours and 40 minutes after fertilization. Immediately after hatching, the total length of larvae was 3.60-3.65 mm (mean 3.62±0.03, n=5) and had an egg yolk without swimming ability. On the third day after hatching, the larvae at the medium stage was 8.00-8.65 mm (mean 8.32±0.45) in total length, and two pairs of whiskers formed around the mouth were elongated. On the 12th day after hatching, the larvae at the juvenile stage was 16.5-17.0 mm (mean 16.7±0.35) in total length, and the stem of each fin was in the range, and the juvenile at this period was morphologically similar to the mother fish.
        75.
        2017.05 서비스 종료(열람 제한)
        Background : Recently, hair loss, which has been regarded as a mere means of middle-aged men due to stress and environmental pollution. The market for hair loss in Korea is about four trillion won and it is growing continuously. It is mainly made by mixing natural extracts such as medicinal plant. The purpose of this study was to investigate the effects of ethanol extracts of Houttuynia cordata Thunb. whole plant and Calendula officinalis L. flower extracts on the growth of fibroblasts, dermal papilla cells and lipid precursors, I want to try to make a materialization. Methods and Results : The cytotoxicity of each sample extracts treated with 50%, 100%, and 500 μg to fibroblasts, cell-viability were 107.3%, 109.6%, and 128.2%, respectively. The cytotoxicity of each sample to the dermal papilla cells was not observed. And the lipid differentiation of the lipogenic precursor cells which regulates the hairegeneration by secretion of the platelet derived growth factor. The 70% ethanol extracts of H. cordata whole plant and C. officinalis flower were showed promotes the hair growth activity. The lipolysis rate was significantly increased with increasing treatment concentration Conclusion : As a result of this study, in-vitro hair growth activity of herbal medicines for hair treatment material development was not shown to be toxic to each cell. And 70% ethanol extract of H. cordata whole plant stimulated lipid precursor cells inducing differentiation. As a result, the 70% ethanol extracts of H. cordata whole plant and C. officinalis flower have potential to developing hair-related product.
        76.
        2017.05 서비스 종료(열람 제한)
        Background : Polygonum multiflorum Thunb. is a herbaceous perennial belonging to the Polygonaceae family. And is an herbal medicine which can be used as a raw material for food, which is excellent in immunity enhancement, vocalization and blood transfusion. The purpose of this study was to expand the utility of the P. multiflorum. Also, we fermented P. multiflorum by mushroom mycelial, and analyzed for general components and amino acids before and after fermentation Methods and Results : The moisture content of P. multiflorum and fermented P. multiflorum by mushroom mycelial (FPM) were 7.35% and 59%, respectively. The crude protein content did not show a significant difference between the two samples, crude fat, ash and crude fiber content of FPM were lower than P. multiflorum. The content of soluble nitrogen free extract of P. multiflorum (79.78%) was significantly higher than FPM (31.05%). Sixteen kinds of amino acids were detected in P. multiflorum, and the major amino acid was determined the arginine. The content of arginine and glutamic acid were 586.67 ㎎%, and 283.78 ㎎%, respectively. Sixteen kinds of amino acids were detected in FPM, and the major amino acids were determined the arginine (654.68 ㎎%) and threonine (591.18 ㎎%). The total amino acid contents of P. multiflorum and FPM were 3,469.03 ㎎%, and 3,630 ㎎%, respectively. Conclusion : The content of crude fat, ash, crude fiber, and soluble nitrogen free extract of FPM were lower than the P. multiflorum, and the major amino acids were different in two samples. Total amino acid content of FPM was higher than the P. multiflorum. As the mushroom fermentation progresses, it is confirmed that the amino acid content is increased, and it is expected to develop the product using the P. multiflorum fermented with mushroom mycelial.
        77.
        2016.10 서비스 종료(열람 제한)
        Background : Ischemic stroke is a common cause of adult disability and death worldwide. Excessive oxidative stress is an important pathogenic mechanism in ischemic stroke. Major reduction of endogenous antioxidative systems increases production of free radicals inducing peroxidation of lipid, protein, and nucleic acid. 1,3-Dipalmitoyl-2-oleoylglycerol (DPOG) is a triglyceride found in oils from various natural sources such as palm kernels, sunflower seeds and rice bran. We found DPOG as an active constituent of rice bran oil. In the present study, we investigated neuroprotective effect of DPOG derived from rice bran oil on excitotoxicity in cultured neurons and on ischemic brain injury in rats. Methods and Results : Transient focal ischemic brain damage was induced by 2 h middle cerebral artery occlusion followed by 24h reperfusion (MCAO/reperfusion) in rats. After MCAO/reperfusion, the infarct and edema volume of brain tissue was measured by 2,3,5-triphenyltetrazolium chloride (TTC) staining methods. Glutathione concentration and lipid peroxidation rate were measured in brain tissue. The expression levels of phosphorylated mitogen activated proteins kinases (MAPKs), inflammatory factors, and anti-apoptotic and pro-apoptotic proteins in brain tissue were detected by Western blot. Cerebral cortical neuronal cells were cultured in 15-days-old fetus. Cortical neurons were incubated with 1 mM N-methyl-D-aspartate (NMDA) for 14 h to produce excitotoxicity. Cell viability was measured by MTT assay. DPOG (1-5 mg/kg) significantly reduced MCAO/reperfusion-induced infarction and edema formation, neurological deficits, and brain cell death. Depletion of glutathione level and lipid peroxidation induced by MCAO/reperfusion were inhibited by administration of DPOG. The increase of phosphorylated MAPKs, inflammatory factors, and proapoptotic proteins and the decrease of antiapoptotic protein in ischemic brain were significantly inhibited by treatment with DPOG. DPOG (0.1-10 uM) inhibited 1 mM NMDA-induced neuronal cell death in cultured cortical neurons. Conclusion : From the above results, the present study provides an evidence that DPOG derived from rice bran oil might be effectively applied for the treatment of ischemic stroke.
        78.
        2016.10 서비스 종료(열람 제한)
        Background : Alzheimer’s disease (AD) is a neurodegenerative disease characterized by progressive memory loss, cognitive impairment and personality defects accompanied by diffuse structural abnormalities in the brain. The major pathological hallmarks of AD include beta amyloid (Aß) protein deposition, presence of neurofibrillary tangles and neurodegeneration of cholinergic neurons. Aß, a 39-43 amino acid proteolytic fragment of amyloid precursor protein, is the major constituent of the senile plaques. Rice bran, the major byproduct of the rice milling industry, is the source of a high quality vegetable oil. Rice bran oil (RBO) has attracted much medicinal attention for its strong hypocholesterolemic properties because of its balanced fatty acid composition and high levels of antioxidant phytochemicals such as oryzanols, tocopherols and tocotrienols. The present study aims to investigate the protective effect of RBO against Aß (25-35)-induced neurotoxicity in in vitro and in vivo. Methods and Results : Memory impairment was produced by intracerebroventricular (i.c.v) microinjection of 15 nmol Aß (25-35) and measured by passive avoidance test in ICR mice. Glutathione concentration, lipid peroxidation rate and acetylcholine esterase activity were measured in mice brain. The expression levels of phosphorylated mitogen activated proteins kinases (MAPKs), inflammatory factors, and anti-apoptotic and pro-apoptotic proteins in mice brains were detected by Western blot. Cerebral cortical neuronal cells were cultured from 15-days-old fetus. Cortical neurons were incubated with 10 μM Aß (25-35) for 36 h. Cell viability was measured by MTT assay. Chronic treatments of RBO (0.1-1 ml/kg, 8 days, p.o.) protected against memory impairment induced by Aß (25-35). Depletion of glutathione level, lipid peroxidation and increased acetylcholine esterase activity by the treatment with Aß (25-35) were inhibited by administration of RBO. The increase of phosphorylated MAPKs, inflammatory factors, and proapoptotic proteins and the decrease of antiapoptotic protein in Aß (25-35)-administered mice brain were significantly inhibited by treatment with RBO. RBO (0.1-5ul/ml) inhibited 10μM Aß (25-35)-induced neuronal cell death in cultured cortical neurons. Conclusion : The present study suggests the role of RBO as a promising therapeutic for neurodegenerative diseases like AD and stroke.
        79.
        2016.10 서비스 종료(열람 제한)
        Background : Rice bran is the outer brown layer of the rice grain and produced when rice is milled. The basic components of rice bran are fiber, lipids, amino acids, vitamins, and minerals. The oil extracted from this bran is called rice bran oil. Although whole rice bran in itself does not have anti-cholesterol properties, its oil offers significant benefits. Ischemic stroke is a major cause of morbidity and mortality worldwide. The cessation or critical reduction of blood flow in brain during acute stroke results in deprivation of the oxygen and glucose supplies, which can produce a local brain ischemia and injury. It is well established that excitotoxicity, a type of neurotoxicity evoked by elevated extracellular glutamate level, is a primary contributor to ischemic neuronal death. The present study aims to investigate the neuroprotective effect of Rice bran oil (RBO) on ischemic brain injury in rats and on excitotoxicity in cultured neurons. Methods and Results : Transient focal ischemic brain damage was induced by 2 h middle cerebral artery occlusion followed by 24 h reperfusion (MCAO/reperfusion) in rats. After MCAO/reperfusion, the infarct and edema volumes of brain tissues were measured using 2,3,5-triphenyltetrazolium chloride (TTC) staining methods. The expression levels of phosphorylated mitogen activated proteins kinases (MAPKs), inflammatory factors, and anti-apoptotic and pro-apoptotic proteins in brain tissue were detected by Western blot. Primary cortical neuronal cultures were prepared using SD rat fetuses on embryonic days 15. Cortical neurons were treated with N-methyl-D-aspartate (NMDA) (1 mM) for 14 h to produce neuronal cell death. Cell viability was measured by MTT assay. RBO inhibited the formation of infartion and edema in MCAO/reperfusion–induced ischemic brains. The increase of phosphorylated MAPKs, inflammatory factors, and proapoptotic proteins and the decrease of antiapoptotic protein in ischemic brains were significantly inhibited by treatment with RBO. RBO (0.01-1ul/ml) inhibited 1 mM NMDA-induced neuronal cell death in cultured cortical neurons. Conclusion : These results suggest that RBO might be a promising therapeutic for neurodegenerative disease such as stroke.
        80.
        2016.07 KCI 등재 서비스 종료(열람 제한)
        High-rank coals are limited, while low-rank coals are abundant. However, the low-rank coals needs upgradation so as to improve their quality. If not, the utilization of low-rank coals will lead to many operational difficulties. As this study was made in South Korea, this article discusses the energy and coal scenario of South Korea. The critique discusses the concerns of utilizing low-grade coal and the need for upgrading low-grade coal. The article also briefly discusses the currently practiced low-rank coal upgradation techniques. Also, the review paper suggests some best upgradation techniques.
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