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Another Evidence for Nitric Oxide as Mediator of Relaxation of Isolated Rabbit and Human Corpus Cavernosum

  • Chang, Ki-Churl
    • Biomolecules & Therapeutics
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    • v.2 no.2
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    • pp.136-140
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    • 1994
  • To prove the hypothesis that NO- and N $O_2$-carrying molecules potentiate photorelaxation by generating NO, investigation was carried out using isolated rabbit and human corpus cavernosum. Corporal smooth muscle, in the presence or absence of endothelium, relaxed only slightly upon ultraviolet light (366 nm) irradiation. But, NO-and/or N $O_2$-containing compounds such as streptozotocin and $N^{G}$-nitro-L-arginine methyl ester significantly (p<0.01) enhanced photorelaxation in this tissue. In addition, $N^{G}$-nitro-D-arginine methyl ester, known to lack inhibitory action on NO synthase, showed concentration-dependent potentiation of the photorelaxation. Oxygen radical generating system via copper+ascorbic acid and guanylate cyclase inhibitor, methylene blue, significantly (p<0.05) inhibited the streptozotocin-potentiated photorelaxation. Nitrite was accumulated by photolysis of streptozotocin, $N^{G}$-nitro-L-arginine methyl ester and $N^{G}$-nitro-D-arginine methyl ester, in a concentration and exposure time dependent manner. These observations indicate that NO is a potent relaxant of rabbit and human corpus cavernosum and further support the hypothesis that NO is released by photolysis from NO- and N $O_2$-carrying molecules.lecules.

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THE FINITE DIMENSIONAL PRIME RINGS

  • Koh, Kwangil
    • Bulletin of the Korean Mathematical Society
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    • v.20 no.1
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    • pp.45-49
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    • 1983
  • If R is ring and M is a right (or left) R-module, then M is called a faithful R-module if, for some a in R, x.a=0 for all x.mem.M then a=0. In [4], R.E. Johnson defines that M is a prime module if every non-zero submodule of M is faithful. Let us define that M is of prime type provided that M is faithful if and only if every non-zero submodule is faithful. We call a right (left) ideal I of R is of prime type if R/I is of prime type as a R-module. This is equivalent to the condition that if xRy.subeq.I then either x.mem.I ro y.mem.I (see [5:3:1]). It is easy to see that in case R is a commutative ring then a right or left ideal of a prime type is just a prime ideal. We have defined in [5], that a chain of right ideals of prime type in a ring R is a finite strictly increasing sequence I$_{0}$.contnd.I$_{1}$.contnd....contnd.I$_{n}$; the length of the chain is n. By the right dimension of a ring R, which is denoted by dim, R, we mean the supremum of the length of all chains of right ideals of prime type in R. It is an integer .geq.0 or .inf.. The left dimension of R, which is denoted by dim$_{l}$ R is similarly defined. It was shown in [5], that dim$_{r}$R=0 if and only if dim$_{l}$ R=0 if and only if R modulo the prime radical is a strongly regular ring. By "a strongly regular ring", we mean that for every a in R there is x in R such that axa=a=a$^{2}$x. It was also shown that R is a simple ring if and only if every right ideal is of prime type if and only if every left ideal is of prime type. In case, R is a (right or left) primitive ring then dim$_{r}$R=n if and only if dim$_{l}$ R=n if and only if R.iden.D$_{n+1}$ , n+1 by n+1 matrix ring on a division ring D. in this paper, we establish the following results: (1) If R is prime ring and dim$_{r}$R=n then either R is a righe Ore domain such that every non-zero right ideal of a prime type contains a non-zero minimal prime ideal or the classical ring of ritght quotients is isomorphic to m*m matrix ring over a division ring where m.leq.n+1. (b) If R is prime ring and dim$_{r}$R=n then dim$_{l}$ R=n if dim$_{l}$ R=n if dim$_{l}$ R<.inf. (c) Let R be a principal right and left ideal domain. If dim$_{r}$R=1 then R is an unique factorization domain.TEX>R=1 then R is an unique factorization domain.

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The serum level of 25-hydroxyvitamin D for maximal suppression of parathyroid hormone in children: the relationship between 25-hydroxyvitamin D and parathyroid hormone

  • Kang, Jung In;Lee, Yoon Suk;Han, Ye Jin;Kong, Kyoung Ae;Kim, Hae Soon
    • Clinical and Experimental Pediatrics
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    • v.60 no.2
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    • pp.45-49
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    • 2017
  • Purpose: Serum level of 25-hydroxyvitamin D (25-OHD) is considered as the most appropriate marker of vitamin D status. However, only a few studies have investigated the relationship between 25-OHD and parathyroid hormone (PTH) in children. To this end, this study was aimed at evaluating the lowest 25-OHD level that suppresses the production of parathyroid hormone in children. Methods: A retrospective record review was performed for children aged 0.2 to 18 years (n=193; 106 boys and 87 girls) who underwent simultaneous measurements of serum 25-OHD and PTH levels between January 2010 and June 2014. Results: The inflection point of serum 25-OHD level for maximal suppression of PTH was at 18.0 ng/mL (95% confidence interval, 14.3-21.7 ng/mL). The median PTH level of the children with 25-OHD levels of <18.0 ng/mL was higher than that of children with 25-OHD levels ${\geq}$ 18.0 ng/mL (P<0.0001). The median calcium level of children with 25-OHD levels<18.0 ng/mL was lower than that of children with 25-OHD levels${\geq}18.0ng/mL$ (P=0.0001). The frequency of hyperparathyroidism was higher in the children with 25-OHD levels<18.0 ng/mL than in the children with 25-OHD levels${\geq}18.0ng/mL$ (P<0.0001). Hypocalcemia was more prevalent in the children with 25-OHD levels<18.0 ng/mL than in the children with 25-OHD levels${\geq}18.0ng/mL$ (P<0.0001). Conclusion: These data suggest that a vitamin D level of 18.0 ng/mL could be the criterion for 25-OHD deficiency in children at the inflection point of the maximal suppression of PTH.

Synthesis and Characterization of Molybdenum(Ⅲ) and (Ⅳ) Complexes with N, P, O-Donating Ligands(Ⅲ) (질소, 산소, 인 주개 리간드를 갖는 몰리브덴 (Ⅲ) 및 (Ⅳ) 착물의 합성과 특성 (제 3 보))

  • Kim, Eun Gi;Yu, Eun Yeong;Park, Yu Cheol
    • Journal of the Korean Chemical Society
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    • v.38 no.2
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    • pp.101-107
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    • 1994
  • Some molybdenum(III) and (IV) complexes have been prepared from the reaction of $MoCl_4$·2MeCN with N, P, O-donating ligands and characterized by elemental analysis, infrared and UV-Visible spectroscopy. 3,5-Lutidine, 1,2-phenylenediamine, 8-hydroxyquinoline, 9,10-phenanthrenequinone, triphenylphosphine and 1,2-bis(diphenylphosphino)ethane were chosen as coordinating ligands. Stretching frequencies $\upsilon$ (Mo-Cl) of Mo(IV) appear at higher frequencies than those of Mo(III) complexes due to the increasing oxidation number of metal. $MoCl_4(L)_2$ exhibit one Mo-Cl stretching frequency, whereas Mo$Cl_4$(L^L) exhibit four Mo-Cl stretching frequencies. The number of Mo-Cl stretching frequency suggestes the former complexes have trans($D_{4h}$) and the latter complexes have cis($C_{2v}$) symmetry. Stretching frequency ${\nu}g(C{\equiv}N)$ of acetonitrile in Mo(III) complexes are shifted to about 30 $cm^{-1}$ higher frequency compared with that of a free ligand (2260 $cm^{-1}$). These spectral data indicates that Mo(III) complexes are in the octahedral geometries with the coordinated acetonitrile. Finally each molybdenum(III) and (IV) complexes showed the following formulation; $[MoCl_4(L)_2]$,[Mo$Cl_4$(L^L)], $[MoCl_3(L)_2MeCN]$ and [Mo$Cl_3$(L^L)MeCN].

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A Survey on Dietary Behaviors and Liquid Consumptions of University Students in Kongju of Chungnam Province in Korea (충남 공주지역 대학생의 식사행동 및 액체섭취실태 조사)

  • Kim, Sun-Hyo
    • Journal of Nutrition and Health
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    • v.42 no.4
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    • pp.327-337
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    • 2009
  • University students tend to have various dietary problems including undesirable dietary behaviors, inadequate intakes of nutrients and biased habits of liquid consumption. This study was conducted to find dietary behaviors (n = 357) by questionnaire survey and to examine dietary nutrient intakes (n = 60) and liquid consumption (n = 853) by food record method for 3-days among university students attended in K University of Chungnam province in Korea. Most subjects lived in the dormitory or self-boarding house, and they skipped breakfast most frequently and took breakfast most irregularly among three meals. Dietary mean intakes of energy, Ca, vitamin B2 and folate were lower than the KDRI (37-85%), and those of males were poorer than those of females. Ratios of energy intake among three meals and snacks were not distributed evenly, so the mean energy intake from snacks was higher and that from breakfast was lower than the ideal ratio, respectively. Daily mean consumption of liquid was 1,526.4 mL/d for males and 1,151.5 mL/d for females, and these intakes were more than the KDRI (1,300 mL/d for males and 1,100 mL/d for females). However, their sources of liquid consumption were not desirable because alcohol, soda, juice of fruit or vegetable and beverage mixed with fruit juice and/or vegetable juice were major sources of liquid as well as drinking water. These findings show that university students have poor dietary behaviors including frequent skipping of breakfast, irregularity of meals, inadequate intakes of nutrients and undesirable pattersirablliquid consumption including high portion of alcohol and soda as alliquid source, and these trends were stronger for males than for females. Therefore, we should endeavor to correct their meal problems id ated to dietary behaviors, nutrient intakes and liquid consumptions through nutrition education.

Plant Regeneration from Embryogenic Callus of Miscanthus spp. (억새(Miscanthus spp.) 배발생 캘러스로부터 식물체 재분화)

  • Kim, Kwang-Soo;Kwon, Da-Eun;Lee, Ji-Eun;Cha, Young-Lok;Moon, Youn-Ho;Kang, Yong-Ku
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.10a
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    • pp.89-89
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    • 2018
  • 우리나라, 중국 및 일본을 포함한 동북아시아가 원산이며 바이오매스량이 많은 억새(Miscanthus spp.)는 바이오에너지 생산을 위한 원료작물로서 가치가 높아, 바이오에탄올 생산용 원료작물로 주목을 받고 있다. 독일 등 유럽과 미국에서는 바이오에탄올 생산용 작물로 주로 종간 교잡 이질 3배체인 불임성 억새(M. x giganteous)를 대상으로 연구하고 있다. 이렇게 단일유전형을 갖는 품종의 재배에는 특정 병과 해충에 약하며 자연재해에도 취약성을 나타내므로 억새가 바이오에너지작물로 자리 잡기 위해서는 다양한 유전형의 억새 품종 개발이 필요하다. 본 연구는 우리나라의 자생 억새 3종을 기내배양하고 탈분화 및 재분화 시스템을 구축하여 억새 품종 육성 시 효율을 높이기 위해서 실시하였다. 억새 종자로부터 캘러스의 유도는 MS배지보다 N6배지 에서 좋았으며, 식물생장조절제로 2,4-Dichlorophenoxyacetic acid (2,4-D)와 6-Benzyl aminopurine (BA)를 조합처리한 처리구보다 2,4-D만을 단독처리하였을 때 캘러스 유도율이 더 높았다. 억새 종에 따른 캘러스 유도율은 물억새가 가장 낮고, 거대억새가 가장 높았으며, 3 ~ 5 mg/L의 2,4-D가 첨가된 N6배지에서 배발생 캘러스(embryogenic callus)가 발생하였다. 억새 신초 및 줄기의 절간에서의 캘러스 유도율은 전반적으로 종자에 비하여 낮았으며, 미성숙화기로부터의 캘러스 유도는 억새 종에 따른 차이가 없었으며, 5mg/L의 2,4-D가 첨가된 배지에서 캘러스 유도율이 가장 높게(90 ~ 95%) 나타났다. 형성된 배발생 캘러스로부터 식물체의 재분화는 N6배지에서는 재분화 식물체가 발생하지 않았고, 1 ~ 3mg/L의 BA와 0.1ml/L의 1-Naphthaleneacetic acid (NAA)가 첨가된 MS배지에서만 식물체가 재분화되였다.

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Mechanical Splicing Characteristic of the Threaded Bar according to the Contact Conditions of the Transverse Rib (마디접촉조건에 따른 나사철근의 기계식 이음 특성)

  • Kim, J.M.;Choi, S.W.;Kim, B.M.
    • Transactions of Materials Processing
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    • v.28 no.3
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    • pp.145-153
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    • 2019
  • The objective of this study is to analyze the mechanical splicing characteristic of the threaded bar according to the contact conditions of the transverse rib. In order to consider the contact conditions of the rib, selection of the main variables including the gap of the core diameter ($l_c$), rib angle (${\theta}$), and the number of contacts ($C_N$) of transverse rib was done. So as to analyze the splicing characteristic of the D51 threaded bar, a finite element (FE) simulation of the tensile test was conducted using the designed D51 threaded bar and coupler. Through FE simulation results, it was verified that the mechanical slicing characteristics varied based on the main design variables ($l_c$, ${\theta}$, and $C_N$). It was further confirmed that it was important to determine the $C_N$ in consideration of $l_c$. Additionally, the tensile test results of the D25 and D51 threaded bar combined with the couplers were similar to FE simulation results. Furthermore, to quantitatively evaluate FE simulation and test results, the calculation equation for the contacted projection area ratio (R) of the transverse rib was proposed. To secure a mechanical splicing joint of the threaded bar, it was established that the R calculated using the proposed equation had to be greater or equal to 40%.

Overproduction of Escherichia coli D-Xylose Isomerase Using ${\lambda}P_L$ Promoter

  • Park, Heui-Dong;Joo, Gil-Jae;Rhee, In-Koo
    • Journal of Microbiology and Biotechnology
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    • v.7 no.1
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    • pp.8-12
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    • 1997
  • In order to overproduce D-xylose isomerase, the Escherichia coli D-xylose isomerase (D-xylose ketol-isomerase, EC 5.3.1.5) gene (xylA) was fused to ${\lambda}P_{L}$ promoter. The promoterless xylA gene containing the ribosome binding site and coding region for D-xylose isomerase was cloned into a site 0.3 kb downstream from the ${\lambda}P_{L}$ promoter on a high copy number plasmid. An octameric XbaI linker containing TAG amber codon was inserted between 33rd codon of ${\lambda}N$ and the promoterless xylA gene. The resulting recombinant plasmid (designated as pPX152) was transformed into E. coli M5248 carrying a single copy of the temperature sensitive ${\lambda}cI857$ gene on its chromosomal DNA. When temperature-induced, the transformants produced 15 times as much D-xylose isomerase as that of D-xylose-induced parent strain. The amount of overproduced D-xylose isomerase was found to be about 60% of total protein in cell-free extracts.

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L'usage du clip publicitaire dans l'apprentissage de la langue française (광고 영상을 활용한 프랑스어 교육 방안)

  • KIM, Eunne Kyung
    • Cross-Cultural Studies
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    • v.37
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    • pp.211-231
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    • 2014
  • Comment faciliter l'apprentissage du français pour rendre notre enseignement plus efficace? Beaucoup de recherches ont ${\acute{e}}t{\acute{e}}$ $men{\acute{e}}es$ sur cette question; en $r{\grave{e}}gle$ $g{\acute{e}}n{\acute{e}}rale$ l'enseignement de la langue d'une part et l'expression ${\acute{e}}crite$ et la $r{\acute{e}}flexion$ d'autre part ${\acute{e}}taient$ $men{\acute{e}}es$ $ind{\acute{e}}pendamment$. Notre intention dans ce $pr{\acute{e}}sent$ travail a ${\acute{e}}t{\acute{e}}$ d'introduire et $d^{\prime}e xp{\acute{e}}rimenter$ pendant $l^{\prime}ann{\acute{e}}e$ scolaire des cours associant le $d{\acute{e}}bat$ $d^{\prime}id{\acute{e}}e$ et la $r{\acute{e}}flexion$ $th{\acute{e}}matique$ avec l'apprentissage linguistique(grammaire, vocabulaire${\dots}$), afin de susciter $l^{\prime}i nt{\acute{e}}r{\hat{e}}t$ des apprenants, leur $curiosit{\acute{e}}$ et leur $vivacit{\acute{e}}$, au $del{\grave{a}}$ des $d{\acute{e}}fis$ $pos{\acute{e}}s$ par la langue française. Nous avons en particulier $utilis{\acute{e}}$ une $publicit{\acute{e}}$ comme support d'apprentissage des bases linguistiques et comme moteur $d^{\prime}{\acute{e}}veil$ ${\grave{a}}$ la civilisation française pour mobiliser leur attention et stimuler leur $activit{\acute{e}}$ cognitive par $l^{\prime}interdisciplinarit{\acute{e}}$. Nous avons donc $expos{\acute{e}}$ ici les exemples d'argumentation autour les deux $s{\acute{e}}quences$ publicitaires conduites avec les ${\acute{e}}tudiants$ et les arborescences $d{\acute{e}}gag{\acute{e}}es$ de ces analyses. Presque concomittamment ${\grave{a}}$ "voir" et "${\acute{e}}couter$", l'information est $trait{\acute{e}}e$ par $l^{\prime}activit{\acute{e}}$ "$d{\acute{e}}coder$". Nous approfondissons ensemble cette $interpr{\acute{e}}tation$ $s{\acute{e}}miotique$, et l'analyse de la façon dont la $publicit{\acute{e}}$ capte l'attention du spectateur nous $am{\grave{e}}ne$ ${\grave{a}}$ $d{\acute{e}}gager$ des faits de $soci{\acute{e}}t{\acute{e}}$ et ${\grave{a}}$ y $r{\acute{e}}fl{\acute{e}}chir$; comment, avec l'exemple de la $publicit{\acute{e}}$ jouant la musique $d{\acute{e}}licieuse$ de la gourmandise, nous entrevoyons la $r{\acute{e}}alit{\acute{e}}$ obscure de $l^{\prime}ob{\acute{e}}sit{\acute{e}}$ infantile. Ces approches interdisciplinaires ${\grave{a}}$ partir du multi-$m{\acute{e}}dia$ $r{\acute{e}}pondent$ ${\grave{a}}$ la $n{\acute{e}}cessit{\acute{e}}$ de distance critique que requiert la $soci{\acute{e}}t{\acute{e}}$ contemporaine. $L^{\prime}{\acute{e}}tude$ d'une $s{\acute{e}}quence$ publicitaire ne permet certes pas $d^{\prime}appr{\acute{e}}hender$ la $soci{\acute{e}}t{\acute{e}}$ française dans sa $globalit{\acute{e}}$, mais en $consid{\acute{e}}rant$ que notre travail consiste tout autant ${\grave{a}}$ stimuler la $facult{\acute{e}}$ critique $qu^{\prime}{\grave{a}}$ favoriser l'apprentissage linguistitique, notre $strat{\acute{e}}gie$ nous permet de $r{\acute{e}}aliser$ plusieurs objectifs autour d'un $m{\hat{e}}me$ axe d'enseignement.

Efficient Plant Regeneration from Mature Seed-derived Callus of Italian ryegrass (Lolium multiflorum Lam.) (이탈리안 라이그래스의 성숙종자 유래 캘러스로부터 효율적인 식물체 재분화)

  • Woo, Hyun-Sook;Lee, Sang-Hoon;Lee, Dong-Gi;Kim, Jin-Soo;Won, Sung-Hye;Lee, Byung-Hyun
    • Journal of Plant Biotechnology
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    • v.31 no.1
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    • pp.43-48
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    • 2004
  • As an initial step for future genetic manipulations to improve forage characteristics of Italian ryegrass (Lolium multiflorum Lam.), an efficient tissue culture system was established and the factors affecting plant regeneration were evaluated. MS medium containing 5mg/L 2,4-D was optimal for embryogenic callus induction from mature seed and had a strong effect on successive plant regeneration. The plant regeneration frequency was observed at above 70% when embryogenic calli induced were transferred to N6 medium supplemented with 1mg/L 2,4-D and 5mg/L BA. Among several basic media tested, MS and N6 medium were optimal for callus induction and plant regeneration, respectively. Genotype was an important factor in plant regenerability. 'Jeanne' showed the highest regeneration frequency of 73%. A short tissue culture period and high-frequency regeneration system established in this study will be useful for molecular breeding of Italian ryegrass through genetic transformation.