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        검색결과 71

        41.
        2009.12 구독 인증기관 무료, 개인회원 유료
        The purpose of this study is to evaluate the effects of alcohol or cigarette smoking on seminal parameters in a large group of mice model. Nine groups (n=20/group) of mice were treated intensive noxious materials that abdominal injection of 21% (v/v) of ethanol, cigarette smoke (10, 20, 30 minutes/day), and combination of ethanol and 30 minutes of smoking. In addition, vitamin C and selenium were also treated to mice exposed to combination of alcohol and smoking to identify the recovering effect. Sperm viability and motility were significantly decreased in either alcohol consumption or smoking exposed group, and combination of both materials have additive detrimental effects on seminal parameters. Mice groups that exposed to alcohol and smoking showed statistically significant decrease in motility and increase of static spermatozoa. Moreover, combination of both treatments showed cumulative effect in increase of static spermatozoa. Treatments of either vitamin C or selenium dramatically recovered detrimental effects of alcohol and smoking on seminal quality, although combination of both antioxidant molecules did not show any additive effect. In conclusion, detrimental effects of alcohol and cigarette consumption on sperm quality and motility were identified in mice model, and these detrimental effects can be compensated to uptake of anti‐oxidant molecules.
        4,000원
        42.
        2008.09 구독 인증기관 무료, 개인회원 유료
        Thrombospondins (TSP-1, TSP-2) are secretory extracellular glycoproteins that are involved in a variety of physiological processes such as tumor cell adhesion, invasion, and metastasis. The present study was undertaken to elucidate the involvement of thrombospondins in the adhesion of osteoblast-like cells using the TSP-1 or TSP-2 antisense MG63 and MC3T3-E1 cell lines. For downregulation of TSPs expression, we prepared antisense constructs for TSP-1 and TSP-2 using the pREP4 an episomal mammalian expression vector, which be able to produce the specific antisense oligonucleotides around chromosome. MG63 and MC3T3-E1 osteoblast-like cells were transfected with the antisense constructs and nonliposomal Fugene 6, and then selected under hygromycin B (50 μM/mℓ) treatment for 2 weeks. Western blot analysis revealed that expression of the TSP proteins was downregulated in the antisense cell lines. The cell adhesion assay showed that adhesive properties of TSP-1 and TSP-2 antisense MG63 cells on the polystyrene culture plate were reduced to 17% and 21% of the control cells, respectively, and those of the TSP-1 and TSP-2 antisense MC3T3-E1 cells also decreased to 19% and 27% of control, respectively. Adhesion of TSP-1 and TSP-2 antisense MC3T3-E1 cells on Type I collagen-coated culture plate decreased to 27% and 76%, respectively. These results indicate that TSP-1 and TSP-2 proteins may have an important role in adhesion of osteoblast-like cells to extracellular matrix.
        4,000원
        43.
        2007.03 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        고연소도 경수로사용후핵연료를 이용하여 voloxidation 및 소결 열처리 공정으로부터 세슘의 시간에 따른 방출 거동을 실험적으로 평가하였다. 사용후핵연료 voloxidation 공정에서는 fragment 형태의 시편을 사용하여 최대 의 산화 및 환원 분위기에 따른 세슘 방출 거동을 상호 비교하였으며, 소결 공정에서는 압분체를 이용하여 4% H2/Ar 환원분위기 에서 열처리 온도 변화에 따른 세슘방출 특성 변화를 분석하였다. 산화 분위기에서 fragment 형태의 사용후핵연료로부터 세슘 방출 온도 구간은 였으며, 환원 분위기에서 압분체로부터 방출 온도 구간은 로서, 산화에 의한 사용후핵 연료의 분말화가 세슘 방출 거동에 영향을 미치는 것으로 나타났다. 아울러 사용후핵 연료로부터 세슘 방출 거동에 영향을 미치는 주요 인자는 사용후핵 연료내 세슘 화합물의 화학적 형태뿐만 아니라 결정립 및 핵연료 표면으로의 확산 속도에 지배를 받음을 알 수 있었다.
        4,300원
        44.
        2007.03 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        사용후핵연료의 건식 재가공을 위한 핵연료 원격 제조공정중 분말제조를 위한 산화 및 OREOX(산화 환원공정)열처리 공정으로부터 및 핵분열기체의 방출거동을 정량적으로 평가하였다. 특히 사용후핵연료의 평균 연소도가 범위내에서 연소도 변화에 따른 핵분열기체의 방출 분율은 측정한 실험결과와 ORIGEN 코드로부터 계산된 초기 inventory를 상호 비교하여 구하였다. 1차 산화공정(voloxidation)에서 및 의 시간에 따른 방출거동은 핵연료의 으로의 분말화 정도와 밀접한 관련이 있는 것으로 보이며, 입계(grain-boundary)에 분포된 핵분열기체가 대부분 방출되는 것으로 여겨진다. 산화분말을 이용한 OREOX 공정으로부터 핵분열기체의 높은 방출율은 의 환원공정에서 온도 증가에 의한 기체 확산 및 으로의 환원에 의한 U 원자 이동성 증가에 의존하며 주로 inter-grain 및 intra-grain에 분포된 핵분열기체가 방출된 것으로 판단된다. 일차 산화공정시 및 핵분열기체의 방출 분율은 핵 연료 연소도가 증가함에 따라 높게 나타났고 방출 분율 범위는 총 inventory의 정도며, 산화분말의 OREOX 공정처리시 잔류 핵분열기체 대부분이 방출되는 것으로 보인다. 아울러 사용후핵 연료로부터 핵분열기체의 제거를 위해서는 고온 환원분위기보다는 산화에 의한 분말화가 더 효과적인 것으로 여겨진다.
        4,600원
        46.
        2004.09 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        In order to vitrify the combustible dry active waste (DAW) generated from Korean Nuclear Power Plants, a glass formulation development based on waste composition was performed. A borosilicate glass, DG-2, was formulated to vitrify the DAW in an induction cold crucible melter (CCM). The processability, product performance, and volume reduction effect of the candidate glass were evaluated using a computer code and were measured experimentally in the laboratory and CCM. The glass viscosity and electrical conductivity as the process parameters were in the desired ranges. Start-up and maintaining glass melt of the candidate glass were favorable in the CCM. The product of the glass product such as chemical durability, phase stability, and density was satisfactory. The vitrification process using the candidate glass was also evaluated assuming that it was operated as economically as possible.
        4,000원
        49.
        2019.11 KCI 등재 서비스 종료(열람 제한)
        This study was conducted to compare the community structure and biodiversity of epigeic spiders between pear fields cultivated by integrated pest management (IPM) and organic methods. This is the first study of this kind to be conducted in Korea. Eighty-four spider species from 22 families were identified among the collected 2,489 arthropods, with 754 individuals being sampled from IPM fields and 1,735 individuals from organic fields. Generally, Theridiidae, Linyphiidae, Lycosidae, Agelenidae, Gnaphosidae, and Salticidae were the dominant spider families in the pear orchard regardless of the farming methods, and species richness and abundance were higher in organic fields than in IPM fields. The dominant species were the wolf spiders (Lycosidae) and stone spiders (Gnaphosidae), and their cumulative abundance was 70.7% in IPM fields and 72.7% in organic fields. The community structure between organic and IPM fields was heterogeneous, with a 45% similarity level. Biodiversity, species richness, abundance, and species diversity index were higher in organic fields than in IPM fields, and significantly different between the farming methods. Seasonal fluctuations in biodiversity were similar in both IPM and organic fields. The species richness and species diversity index increased and the abundance decreased in the second half of the cultivation period. This study on the community structure and biodiversity of epigeic spiders, which form one of the most important predator groups, will provide principal ecological and faunistic information required to maintain the biodiversity of useful arthropods in agricultural ecosystems and help implement sustainable agriculture based on the active use of natural enemies.
        50.
        2018.04 서비스 종료(열람 제한)
        Extravasation is the accidental injection or leakage of fluid into the subcutaneous or perivascular tissues. Some drugs can cause serious injury such as severe tissue injury, necrosis, and etc. Here we report a case of chemical burn by sodium bicarbonate extravasation due to accidental venous puncture during arterial cannulation. A 42-years-old woman has taken emergency laparotomy surgery due to a stab wound to the abdomen. Massive blood loss has developed, and consequently vital signs were unstable and metabolic acidosis has developed. Sodium bicarbonate has administered via a peripheral intravenous line on the dorsal vein of a right hand that runs to the cephalic vein. However, the cephalic vein that runs by the side of the radial artery has punctured accidentally during the attempt of right radial artery cannulation. Second degree superficial and deep chemical burn by sodium bicarbonate extravasation has developed. Skin lesion about 3 × 4 cm2 with erythema and bullae formation has developed. There were no necrotic changes and the digital sensation was intact. Wet dressing and silicon foam dressing were prescribed. After two weeks, she was discharged. Until then, dermis exposure about 1 × 1 cm2 remained although the skin lesions became getting well.
        51.
        2017.05 서비스 종료(열람 제한)
        Background : This study was carried out to provide the basic data for selection of excellent resources and true seeds of southern medicinal plant (Camellia japonica). Methods and Results : Camellia japonica seedlings (measure in October, seeding in May) were 7.4 leaves, 1.0 g leaf dry weight, 6.7 ㎝ stem length, 2.9 ㎜ stem diameter, 0.3 g stem dry weight, 17.3 ㎝ root length, 1.0 g root dry weight, 2.0 g plant dry weight and 1.4. T/R ratio. Leaf number, leaf dry weight, stem diameter and root dry weight were higher than average after 1.21 g of seed weight. Stem length was higher than average after 1.01 g of seed weight, plant dry weight was higher than average after 0.81 g of seed weight, and stem dry weight was higher than average after 0.61 g of seed weight. Seedling growth was good when the seeds were heavy, and T/R ratio tended to decrease when the seeds were heavy. Conclusions : In order to mass-produce of seedlings using Camellia japonica seeds, it was necessary to specify the weight and size of the seeds.
        52.
        2017.05 서비스 종료(열람 제한)
        Background : This study was carried out to provide the basic data for selection of excellent resources and true seeds of southern medicinal plant (Camellia japonica). Methods and Results : The germination rate at room temperature and 4℃ dry storage did not show a tendency according to seed weight. The germination rate of 4℃ wet sand storage increased with seed weight but showed very low germination rate at 120 days of storage. The germination rate at 4℃ wet filter paper storage was higher than 80% in 60 days, 90 days and 120 days storage, and there was no difference in germination rate with seed weight. The mean number of germination days was about 30 days in average at room temperature and 4℃ dry storage, but wet storage (sand, filter paper) was short as about 13 days. Conclusions : The seeding of Camellia japonica seeds (last autumn harvest) in the spring of the next year was evaluated as the most efficient way to 4℃ wet filter paper storage
        53.
        2016.05 서비스 종료(열람 제한)
        Background : Curcuma longa L., in the family Zingiberaceae, is distributed in tropical and/or sub-tropical regions mainly in India and China. This species is commonly called turmeric, powder is used as medicinal herbs and/or flavor enhancer. It has been cultivated in southern region mainly Jindo. However, it might be possible to extend cultivation regions due to rise in average temperature. In order to select superior lines based on agronomic characteristics, we analyzed multivariate and estimated selection effects from C. longa germplasm. Methods and Results : The C. longa germplasm were cultivated in an experimental field located in Eumseong, NIHHS, RDA. The harvested roots were investigated in agronomic characteristics included in yield and then considered its relationship among the 9 germplasm by multivariate analysis method. Results from principal component analysis (PCoA) showed that it represented 70.00% and 80.44% accumulated explanation from four and five principal compounds (PC). PCoA was conducted from 9 agronomic characteristics and then correlation coefficient has been showed by analysis between each main component value and agronomic characteristics. Value of the first PC was 2.25, 24.96% explanation of total dispersion, plant height, number of rootlet and weight of rootlet were correlated with a somewhat higher level as 0.41, 0.43 and 0.52. Value of the fifth PC was 0.94, 10.43% explanation of total dispersion, the number of shoots was correlated with a higher level as 0.87. Selection effects with outstanding candidate lines including higher lines were estimated at 126.13% in yield. Conclusion : These data on multivariate based on agronomic characteristics will be give us invaluable breeding information by selection of superior lines.
        54.
        2015.09 서비스 종료(열람 제한)
        Harmonized actions of ovarian estrogen (E2) and progesterone (P4) regulate cell proliferation and differentiation in the uterus with a spatiotemporal manner. Imbalance between the actions and levels of two major regulators often lead to infertility and gynecological diseases, such as endometriosis and endometrial cancer. While numerous works have shown that reduced expression and/or deletion of uterine factors associated with P4 signaling could disturb uterine physiology, local factor(s) to mediate E2 actions has not been extensively studied yet. Here we demonstrate that early growth response 1 (Egr1), a transcription factor which is rapidly induced in the uterus by E2, is required to maintain coordinated actions of E2 and P4 for uterine receptivity for embryo implantation. Given exogenous gonadotrophins to overcome LHβ deficiency in the pituitary of Egr1(-/-) mice, ovulation, fertilization and embryo development normally occurred in these mice. However, they showed complete failure of embryo implantation with reduced uterine responses to artificial decidualization stimuli. While serum levels of E2 and P4 in Egr1(-/-) mice were comparable, genes regulated by E2 and/or P4 in uterine epithelial cells (ECs) were aberrantly expressed on day 4 of pregnancy. Impaired P4 signaling along with absence of PR in ECs caused hypersensitive E2 responses shown as enhanced expression of E2-responsive genes such Muc1 and Ltf as well as reduced levels of P4-dependent genes, such as Ihh and Areg, in ECs of Egr1(-/-) mice. This is consistent with persistent proliferation in ECs and severely impaired proliferation in stromal cells (SCs) in Egr1(-/-) mice treated with E2+P4. Furthermore, primary co-culture of Egr1(-/-) ECs with Egr1(+/+) SCs and vice versa supported a notion that Egr1 itself is required for proper responses to two major regulators, E2 and P4, in both uterine cell compartments. Collectively, our results show that E2-induced Egr1 participates in P4-dependent modulation on E2 activities in the uterus by regulating a spectrum of genes essential for uterine receptivity and embryo implantation.
        55.
        2014.09 서비스 종료(열람 제한)
        The transcription factor, early growth response protein 1 (EGR1), act as immediate early response genes to control various cellular and reproductive events. Egr1-deficient female mice show infertility by anovulation resulting from luteinizing hormone-β (LH-β) subunit deficiency. While ovulation, fertilization and embryo development normally occur in Egr1-deficient mice treated with a superovulation regime to rescue LH deficiency, embryo implantation was completely failed. The morphology and ultrastructure of uterine tissues were observed by light and transmission electron microscopy during the peri-implantation period in Egr1-deficient mice. To examine alterations in cellular organelles, the uterine horns were fixed with 2.5% glutaraldehyde and postfixed with 1% osmium tetroxide in PBS. After dehydration and infiltration, the samples were embedded in Epon 812. Semi-thin sections 0.5 μm thick were cut with an ultramicrotome and stained with toluidine blue for light microscopy. Thin sections were cut with a diamond knife of the ultramicrotome and placed on copper grids. The sections were double stained and examined under a transmission electron microscope. The height of luminal epithelial cells was decreased and the polarity was poorly differentiated in the Egr1-deficient comparing to the wild mice. The abundant mucinous materials were observed in the surface of luminal epithelial cells of the Egr1-deficient. It was confirmed the microarray and real time qPCR data. The luminal epithelial cells of wild mice had many dense lipophilic granules and healthy mitochondria, but not in the Egr1-deficient. It may related to production and secretion of steroid hormones and prostaglandins in the luminal epithelial cells for successful implantation. These results show that Egr1 is a critical transcription factor to fine-tune subcellular morphological and functional changes for the receptive phase of peri-implantation period of uterine tissue in mice.
        56.
        2014.03 KCI 등재 서비스 종료(열람 제한)
        Early growth response 1 (Egr1) is a zinc-finger transcription factor to direct second-wave gene expression leading to cell growth, differentiation and/or apoptosis. While it is well-known that Egr1 controls transcription of an array of targets in various cell types, downstream target gene(s) whose transcription is regulated by Egr1 in the uterus has not been identified yet. Thus, we have tried to identify a list of potential target genes of Egr1 in the uterus by performing multi-step in silico promoter analyses. Analyses of mRNA microarray data provided a cohort of genes (102 genes) which were differentially expressed (DEGs) in the uterus between Egr1(+/+) and Egr1(–/–) mice. In mice, the frequency of putative EGR1 binding sites (EBS) in the promoter of DEGs is significantly higher than that of randomly selected non-DEGs, although it is not correlated with expression levels of DEGs. Furthermore, EBS are considerably enriched within –500 bp of DEG’s promoters. Comparative analyses for EBS of DEGs with the promoters of other species provided power to distinguish DEGs with higher probability as EGR1 direct target genes. Eleven EBS in the promoters of 9 genes among analyzed DEGs are conserved between various species including human. In conclusion, this study provides evidence that analyses of mRNA expression profiles followed by two-step in silico analyses could provide a list of putative Egr1 direct target genes in the uterus where any known direct target genes are yet reported for further functional studies.
        57.
        2012.06 KCI 등재 서비스 종료(열람 제한)
        The antioxidant potential and enzyme activities in Salicornia herbacea, Corylopsis coreana, Erythronium japonicum, Phragmites communis, Momordica Charantia, Nelumbo nucifera, Salvia plebeia, Portulaca oleracea, Ficus carica, Citrus junos and Cornus officinalis were determined. Their antioxidant activities were measured using DPPH radical scavenging and nitrite scavenging activity. Enzyme activities in investigated plants were evaluated as superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX). The DPPH scavenging rate from 100 to 2500 mgL-1 was the highest in the flower of Corylopsis coreana. However, it was not detected in most of the samples at concentration below 100 mgL-1. The nitrite scavenging activity according to each kind of resource plants was significantly higher in the stem of Corylopsis coreana and leaf of Nelumbo nucifera. The root extract of Erythronium japonicum had the highest SOD enzyme activity of 94.0% while leaf of Salvia plebeia showed the lowest SOD enzyme activity of 30.4%. The activity of CAT and APX showed higher values in the stem of Corylopsis coreana, root of Erythronium japonicum and root of Phragmites communis in comparison with other plants. The activity of POD showed significantly high values in stem of Corylopsis coreana, Momordica Charantia and pericarp of Citrus junos extracts. The antioxidant enzyme activities differ significantly in different plants. In conclusion, we showed that Corylopsis coreana, Erythronium japonicum Cornus officinalis, and Momordica Charantia had the potent biological activities. Therefore, these plant resources showing antioxidant activity could be good materials for development of source of functional healthy food.
        58.
        2011.09 KCI 등재 서비스 종료(열람 제한)
        Ethanol treatment during the brain growth spurt period has been known to induce the death of Purkinje cells. The underlying molecular mechanisms and the role of reactive oxygen species (ROS) in triggering ethanol-induced Purkinje cell death are, however, largely unresolved. We undertook TUNEL staining, western blotting assay and immunohistochemistry for the cleaved forms of caspase-3 and -9, with calbindin D28K double immunostaining to identify apoptotic Purkinje cells. The possibility of ROS-induced Purkinje cell death was immunohistochemically determined by using anti-8-hydroxy-2'deoxyguanosine (8-OHdG), a specific cellular marker for oxidative damage. The results show that Purkinje cell death of PD 5 rat cerebellum following ethanol administration is mediated by the activation of caspase-3 and -9. However, unexpectedly, TUNEL staining did not reveal any positive Purkinje cells while there were some TUNEL-positive cells in the internal and external granular layer. 8-OHdG was detected in the Purkinje cell layers at 8 h, peaked at 12-24 h, but not at 30 h post-ethanol treatment. No 8-0HdG immunoreactive cells were detected in the internal and external granular layer. The lobule specific 8-OHdG staining patterns following ethanol exposure are consistent with that of ethanol-induced Purkinje cell loss. Thus, we suggest that ethanol-induced Purkinje cell death may not occur by the classical apoptotic pathway and oxidative damage is involved in ethanol-induced Purkinje cell death in the developing cerebellum.
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