• Title/Summary/Keyword: ${\beta}$-phase

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Chiral separation of $\beta$-blockers after derivatizalion wilh a new chiral derivalizalion agen1.GATC and Comparison wilh GITC on derivalizing conditions and chromalographic paramelers

  • Ko, Mi-Young;Shin, Dae-Hong;Seo, Sang-Hun;Kim, Kyeong-Ho
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.398.1-398.1
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    • 2002
  • A new chiral derivatization agent with sugar moiety. 2, 3.4, 6-tetra-O-acetyl-D-galactopyranosyl isothiocyanate (GATC) was synthesized. Several $\beta$-blockers were investigated for the possible separation of the enantiomers by reversed-phase HPLC after derivatization with this new chiral derivatization agent (GATC). GATC was reacted readily with $\beta$-blockers at room temperature and the reaction mixture could directly be injected into the HPLC system. (omitted)

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Crystal structures and magnetic properties of Mn-Al-M (M=Cu, Fe) alloys (Mn-Al-M(M=Cu, Fe) 합금계의 결정구조 및 자기적 성질)

  • Choe, Won-Gyu;Go, Gwan-Yeong;Yun, Seok-Gil
    • Korean Journal of Materials Research
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    • v.5 no.1
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    • pp.22-35
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    • 1995
  • In this study, crystal structures and magnetic properties of as-ast, annealed and rapidly solidified Mn-A1-M( M=Cu, Fe) alloys have been investigated. In $Mn_{0.56}Al_{0.44}$ alloys, the largest fraction of $\tau$ phase and values of magnetic properties was obtained in Mnl, i6Alo or alloy. And this alloy was used as the basic composition. In $Mn_{0.56-X}M_{X}Al_{0.44}$ alloys, when annealed, $\tau$- and $\beta$-Mn phase appeared at x< 0.08, $\tau$- and $\kappa$ phase at 0.10 $\leq x \leq$ 0.12 and $\kappa$- phase only at 0.15 $\leq x \leq$0.20 . When rapidly solidified, specimens showed similar phases as when annealed except that $\varepsilon$ phase appeared at x=0.04. In Mnu FexAlo 44 alloys, asyast specimens showed $\tau$-, $\beta$-Mn and $\gamma_2$- phase at x<0.08 and K and $\beta$-Mn phase at x>0.10. When rapidly solidified, Mn-Fe-Al specimens showed $\varepsilon$-, $\gamma_2$- and small amount of $\tau$- and $\kappa$ phase at x<0.08 and $\kappa$- phase only at 0.$\leq x \leq$0.20. All the alloys investigated were ferromagnetic. The Curie temperature of annealed specimens and rapidly solidified of Mno 5sAlu 44 alloy were -650K and -644K. Spontaneous magnetization( UII of annealed and rapidly solidified specimens were 40-45 (emu/g) and 50-52(emu/g), respectively. Remanent (M,) to saturation magnetization( Ms) ratio was -0.7. M, of rapidly solidified specimen was about 48(emu/g). Magnetic properties of $Mn_{0.56}Al_{0.44}$ alloys were found to be determined by the relative fraction of ferromagnetic r- and K- phase. When M= Cu and x=0.15, maximum as($\sigma_{0.0}$) was obtained by about 64.3 emu/g), and when M=Fe and x=0.15, 66.4( emu/g). The Curie temperature decreased as x increased.

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Factors Influencing Health-related Quality of Life of Patients with Chronic Obstructive Pulmonary Disease (만성폐쇄성폐질환자의 건강 관련 삶의 질에 영향을 미치는 요인)

  • Kim, Na Hyoun;Park, Jin-Hee
    • Journal of muscle and joint health
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    • v.23 no.3
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    • pp.159-168
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    • 2016
  • Purpose: The purpose of this study was to identify the factors influencing health-related quality of life (HRQOL) of patients with chronic obstructive pulmonary disease (COPD). Methods: A sample of 108 Patients diagnosed with COPD was recruited from outpatients, at a university hospital. Data were collected from February to April in 2016 using the St. George's Respiratory Questionnaire, the Hospital Anxiety-Depression Scale, and the COPD Self-efficacy scale. Results: The average score of HRQOL was 47.56 in patients with COPD. Results of the regression analysis showed that dyspnea phase (${\beta}$=.34, p<.001) and presence or absence of oxygen (${\beta}$=.20, p=.009), anxiety (${\beta}$=.29, p<.001), $FEV_1$ % predicted (${\beta}$=-.15, p=.014) were statistically significant in patients' HRQOL. Conclusion: The research findings show that dyspnea phase and anxiety among psychological factors were the most powerful factors that explain the HRQOL of COPD patients when the demographic and disease characteristics were controlled. Identification of quality of life-related factors should be used to inform targeted interventions, in order to improve HRQOL and help patients' cope.

Effects of Photoperiod Manipulation on Gonadal Activity of the Damselfish, Chromis notata

  • Lee, Chi-Hoon;Park, Young-Ju;Lee, Young-Don
    • Development and Reproduction
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    • v.21 no.2
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    • pp.223-228
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    • 2017
  • This study investigated the effect of different photoperiods (14L: 10D, 12L:12D and 10L:14D) on the gonadal development and GtH mRNA expression in the pituitary of damselfish. The results showed that gonadosomatic index (GSI) was significantly lower in shot photoperiod (10L:14D), in comparison with other photoperiodic group during the spawning season. After 60 days treatment, histological analysis of gonad tissue showed that the gonad of 10L:14D and 12L: 12D treatment groups were resting phase with spermatogonia and perinucleolus stage oocytes but the gonad of 14L:10D treatment group was still ripe phase with spermatozoa and mature stage oocyte. The $FSH{\beta}$ and $LH{\beta}$ mRNA expression in pituitary drastically decreased shot photoperiod treatment from July (spawning period). These results suggest that photoperiod is considered to be the most effective environmental factor in controlling the reproductive cycle of damselfish.

Efficient Expression of a Carbon Starvation Promoter Activity Under Nutrient-Limited Chemostat Culture

  • KIM DAE-SUN;PARK YONG-IL;LEE HYANG BURM;KIM YOUNGJUN
    • Journal of Microbiology and Biotechnology
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    • v.15 no.3
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    • pp.678-682
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    • 2005
  • The promoter region of a carbon starvation gene isolated from Pseudomonas putida was cloned and analyzed for its potential use for in situ bioremediation and bioprocessing. We constructed a recombinant plasmid pMKD101 by cloning the 0.65 kb promoter region of the gene into the promoter proving vector, pMK301, which contains the lacZ for ${\beta}$-galactosidase activity as a reporter gene. pMKD101 was transformed into the wild-type P. putida MK1, resulting in P. putida RPD101, and analyzed for ${\beta}$-galactosidase activity under different culture conditions. When RPD101 was grown on the minimal medium plus $0.1\%$ glucose as a sole carbon source in batch cultures, ${\beta}$-galactosidase activity was found to be 3.2-fold higher during the stationary phase than during the exponential phase. In chemostat cultures, ${\beta}$-galactosidase activity was found to be 3.1-fold higher at the minimal growth rate (dilution rate=$0.05\;h^{-1}$) than at the maximal growth rate (dilution rate=$0.173;h^{-1}$). The results suggest that a carbon starvation promoter can be utilized to maximize the expression of a desired gene under nutrient limitation.

Theoretical Studies on Electrophilic Substitution of Five-membered Heteroaromatic Compounds with Isopropyl Cation (5각-이종원자 방향족 고리화합물과 이소프로필 양이온간의 친전자 치환반응에 관한 이론적 연구 (1))

  • Lee, Ik Choon;Kim, Chang Gon;Lee, Bon Su
    • Journal of the Korean Chemical Society
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    • v.34 no.3
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    • pp.248-254
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    • 1990
  • Theoretical studies on the electrophilic substitution reactions of five-membered heteroaromatic compounds, furan, pyrrole and thiophene, with isopropyl cation were carried out using the MNDO method. The results indicated that site selectivities of ${\alpha},{\beta}$ and hetero-atoms are not controlled by electrostatic interactions but are determined mainly by charge trasfer stabilization between the HOMO of heteroaromatics and the LUMO of the electrophile. The reactivity order for ${\alpha}\;and\;{\beta}$ positions was pyrrole > furan > thiophene, in agreement with the solution-phase as well as the gas-phase experimental results.

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Enhancement of Solubility and Disolution Rate of Poorly Water-soluble Naproxen by Coplexation with $2-Hyldroxypropylo-{\beta}-cyclodextrin$

  • Lee, Beom-Jin;Lee, Jeong-Ran
    • Archives of Pharmacal Research
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    • v.18 no.1
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    • pp.22-26
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    • 1995
  • The solubility and dissolution rate of naproxen (NPX) complexed with 2-hydroxypropyl-.betha.-cyc-lodextrin (2-HP.betha.CD) using coprecipitation, evaporation, freeze-drying and kneading method were investigated. Solubility of NPX linearly increased (correlation cefficient, 0.995) as $2-HP\betaCD$ concentraction increased, resutling in $A_l$ type phase solubility curve. Inclusion complexes prepared by four different methods were compared by different methods were compared by dfferential scanning calorimetry(DSC). The NPX showed sharp endothemic peak around $156^{\circ}C$ but inclusion complexes by evaporation, freeze-drying and kneading method showed very broad peak without distinct phase transtion temperature. In contrast, inclusion complex prepared by coprecipitation method resulted in detectable peak around $156^{\circ}C$ which is similar to NPX, suggesting incoplete formation of indusion co plex. Dissolution rate of inclusion complexes prepared by evaporation, frezz-drying and kneding except coprecipitation method was largely enhanced in the simultaed gastric and intestinal fluid when compared to NPX powder and commercial $NA-XEN^\registered$tablet. However, about 65% of NPX in gstric fluid. in case of inclusion complex prepared by coprecipitation method, formation of inclusion complex appeared to be incoplete, resulting in no marked enhancement of dissolution rate. From these findings, inclusion complexes of poorly water-soluble NPX with $2-HP\betaCD$ were useful to increase soubility and dissolution rate, resting in enhancement of bioavailability and minimization of gastrointestinal toxicity of drug upon oral administration of inclusion complex.

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Development of an enzyme immunoassay for determination of steroid hormones to improve the reproductive efficiency of domestic animals (가축(家畜)의 번식효율증진(繁殖效率增進)을 위한 steroid hormones 의 효소면역분석법(酵素免疫分析法) 개발(開發))

  • Choi, Han-sun;Kang, Byong-kyu
    • Korean Journal of Veterinary Research
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    • v.33 no.4
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    • pp.611-615
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    • 1993
  • A rapid, solid-phase microtitre plate enzyme immunoassay(EIA) to determine the concentration of progesterone and testosterone in dairy cow is described. Both steroid hormones were analysed employing antibodies against $11{\alpha}$-hemisuccinate-progesterone bovine serum albumin and 4-androsten-$17{\beta}$-ol-3-one-carboxymethyloxime bovine serum albumin, respectively. as primary antibodies and sheep Ig G as secondary antibody. The conjugated used as labels for progesterone and testosterone was progesterone-$11{\alpha}$-hydroxy-hemisuccinate- horseradish peroxidase and 4 ${\alpha}$-androsten-$17{\beta}$-ol-3-hemisuccinate- horseradish peroxidase, respectively. Detection limit of microtitre plate EIA was 6.7 pg/well for progesteone and 1.0 pg/well for testosterone.

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Steroid modification with aspergillus phoenices (Aspergillus phoenicis를 이용한 steroid의 변형)

  • 김말남;이영종
    • Korean Journal of Microbiology
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    • v.23 no.4
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    • pp.297-301
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    • 1985
  • The dependence of activities of Aspergillus phoenicis on the culture conditions in the progesterone transformation reaction was investigated. In the beginning of the reaction, $6{\beta},\;11{\alpha}-dihydroxyprogesterone$ was not produced even at high concentration of $11{\alpha}-hydroxyprogesterone$. However, large amount of the product was obtained after the complete exhaustion of progesterone. When spores of A.phoenicis replaced mycelia as enzyme source, $11{\alpha}-hydroxyprogesterone$ was produced after a considerably long indyction period, and its maximum production rate followed the exponential growth phase. The $6{\beta}-hydroxylation\;of\;11{\alpha}-hydroxyprogesterone$ continued, even after the stationary growth phase. A. phoenicis showed high enzyme activity for these reactions when the phosphate buffer solutions were used in place of the ordinary culture medium. The buffer solutions of low pH gave more yield of $11{\alpha}-hydroxyprogesterone$ than those of high pH. However, the addition of flucose to the buffer solutions did not activate the transformation reaction. The presence of progesterone seems to be necessary for the induction of enzymes for the $6{\beta}-hydroxylation\;of\;11{\alpha}-hydroxyprogesterone\;since\;6{\beta},\;11{\alpha}-dihydroxyprogesterone$ is not produced in the reaction medium containing only $11{\alpha}-hydroxyprogesterone$ as a substrate.

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Determination of ${\beta}$-sitosterol in Unsaponifiable Fraction of Zea mays and Related Drug Preparations by HPLC (HPLC에 의한 Zea mays 불검화추출물과 그의 함유제제 중 ${\beta}$-시토스테롤의 정량)

  • Kim, Kyeong-Ho;Park, Woo-Sun;Shim, Chang-Gu
    • YAKHAK HOEJI
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    • v.40 no.2
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    • pp.149-154
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    • 1996
  • A high-performance liquid chromatographic method for the determination of ${\beta}$-sitosterol in the unsaponifiable fraction of Zea mays L. and its related drug preparations using a cholesterol as an internal standard was investigated. They were saponified with 20% methanolic KOH solution. Phytosterols in the reaction mixture were extracted with diethyl ether and separated on silica gel TLC plate with n-hexane-diethyl ether(40:60) as the solvent and then were scraped off. They were separated by reversed phase high perfomance liquid chromatography on Inertsil ODS-2 column with detection at 205nm. Cholesterol and ${\beta}$-sitosterol were resolved from interferences by adjusting the acetonitrile content in the MeOH-tetrahydrofuran-$H_2O$ eluent. The detection limit of ${\beta$-sitosterol was 0.43${\mu}$g.

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