• 제목/요약/키워드: $K_{1c}$

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핵산 모델로서 Phosphate Diester들의 가수분해 반응 (Hydrolysis of Phosphate Diesters as Nucleic Acid Model)

  • 성낙도
    • Applied Biological Chemistry
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    • 제37권6호
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    • pp.447-450
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    • 1994
  • RNA의 가수분해시에 생성되는 cyclic phosphate 중간체의 모델 화합물인 ethylene phosphate의 P-O결합 분해속도 상수는 $100^{\circ}C$ 에서 $k=3{\times}10^{-7}s^{-1}({\Delta}H{\neq}=24\;kcal,\;{\Delta}S{\neq}=25.5\;eu)$이었으며 DNA모델 화합물인 dimethylphosphate는 $150^{\circ}C$에서 $1{\times}10^{-11}s^{-1}({\Delta}H{\neq}=36\;kcal,\;{\Delta}S{\neq}=25.5\;eu)$이었다. RNA모델 화합물인 hydroxyethylmethylphosphate의 가수분해는 dimethylphosphate의 C-O결합이 가수분해되는 반응속도와 비교될 만한 정도의 반응속도가 관측되었다.

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13C NMR-Study of 1,1-Dipotassio-2,3,4,5-Tetraphenyl-1-Silacyclopentadienide Dianion [SiC4Ph4] 2-·2[K+ ] and 1,1-Dipotassio-2,3,4,5-Tetraphenyl-1- Germacyclopentadienide Dianion [GeC4Ph4] 2-·2[K+ ]

  • Hong, Jang-Hwan
    • 통합자연과학논문집
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    • 제10권3호
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    • pp.131-136
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    • 2017
  • The chemical shifts in the $^{13}C$ NMR spectra of 2,3,4,5-tetraphenyl-1-silacyclopentdienide dianion $[SiC_4Ph_4]^{2-}{\cdot}2[K^+]$ (3) and 2,3,4,5-tetraphenyl-1-germacyclopentdienide dianion $[GeC_4Ph_4]^{2-}{\cdot}2[K^+]$ (4) were compared to those of $[SiC_4Ph_4]^{2-}{\cdot}2[Li^+]$ (5), $[SiC_4Ph_4]^{2-}{\cdot}2[Na^+]$ (6), and $[GeC_4Ph_4]^{2-}{\cdot}2[Li^+]$ (7). The average polarizations in two phenyl groups of two potassium salts are decreased over 15% to 20% comparing to those of the lithium salts and sodium salt {$[EC_4Ph_4]^{2-}{\cdot}2[M^+]$ (E=Si, Ge, M=Li, Na) due to the effect of the counter potassium cation.

2-Chloromethyl-1-Dihydroxyphosphinylpyrrolidine (2C-1DPP)에 의한 백혈병 세포주 HL-60의 분화유도 효과 (Effect of 2-Chloromethyl-1-Dihydroxyphosphinylpyrrolidine(2C-1DPP) on Differentiation Induction of Human Leukemia HL-60 Cells)

  • 김영미;주성민;박준호;오정미;이채호;김은철;전병훈;김원신;김원신
    • 동의생리병리학회지
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    • 제21권4호
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    • pp.940-945
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    • 2007
  • We have examined the induction of HL-60 cell differentiation by treatment of 2-chloromethyl-1-dihydroxyphosphinyl pyrrolidine(2C-1DPP), which is derivative of piperidine and pyrrolidine by ${\alpha}-phosphoramidoakylation$ reaction. It was observed that HL-60 cell proliferation was dose- and time-dependently inhibited by treatment with 2C-1DPP. 2C-1DPP treatment caused a significant change in NBT reduction and enhanced ATRA-induced NBT reduction. Treatment of 2C-1DPP to HL-60 cells increased only CD11b expression in the cells, and also increased markedly G0/G1 stage arrest of HL-60 cells. These results can suggest that 2C-1DPP induced the differentiation of HL-60 cells to granulocytes lineage and enhanced ATRA-induced differentiation. Moreover, DNA expression levels of p27 were up-regulated during 2C-1DPP-dependent HL-60 cell differentiation. Our results suggest that 2C-1DPP have potential as a therapeutic agent in human leukemia.

MEROMORPHIC FUNCTIONS SHARING A NONZERO POLYNOMIAL CM

  • Li, Xiao-Min;Gao, Ling
    • 대한수학회보
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    • 제47권2호
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    • pp.319-339
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    • 2010
  • In this paper, we prove that if $f^nf'\;-\;P$ and $g^ng'\;-\;P$ share 0 CM, where f and g are two distinct transcendental meromorphic functions, $n\;{\geq}\;11$ is a positive integer, and P is a nonzero polynomial such that its degree ${\gamma}p\;{\leq}\;11$, then either $f\;=\;c_1e^{cQ}$ and $g\;=\;c_2e^{-cQ}$, where $c_1$, $c_2$ and c are three nonzero complex numbers satisfying $(c_1c_2)^{n+1}c^2\;=\;-1$, Q is a polynomial such that $Q\;=\;\int_o^z\;P(\eta)d{\eta}$, or f = tg for a complex number t such that $t^{n+1}\;=\;1$. The results in this paper improve those given by M. L. Fang and H. L. Qiu, C. C. Yang and X. H. Hua, and other authors.

(感光性 高分子에 關한 硏究 VII) Cinnamoylated Polymers의 光增感 硬化反應機構 ((Photosensitive Polymers VII) Mechanism of Photosensitized Curing Reaction of Cinnamoylated Polymers)

  • 김광섭;심정섭
    • 대한화학회지
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    • 제10권4호
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    • pp.166-174
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    • 1966
  • cinnamoylated photosensitive polymer의 광증감 경화반응기구를 반응속도론적으로 연구했다. Cinnamic acid(C)와 증감제(S)의 first excited singlet and lowest triplet energy level diagram과 증감제의 농도증가에 따른 sensitivity의 포화 등의 사실로부터 이 반응의 주요과정은 C와 S의 광 energy흡수에 의한 $C^{*(1)}$$S^{*(1)}$로의 여기, $S^{*(1)}{\to}S^{*(3)}$ intersystem crossing, S의 excimer 형성, $S^{*(3)}{\to}C^{*(3)}$ energy transfer 그리고 $C^{*(3)}$와 C의 termination 등임을 가정하고 다음 반응속도를 구했다. $-\frac{d[C]}{dt} = \frac{K_1[C]}{K_2 + [C]}[\frac{I^c_{abs}}{K_3 + [S]} + \frac{K_4[C]}{(K_5 + [C])(K_6 + [S])}(I^s_{abs} + \frac{K_7I^c_{abs}[S]}{K_8 + [S]})]$ $I^c_{abs}$$I^s_{abs}$ ;C 및 S의 광흡수율 $K_n$;상수 적외선 흡수스펙트럼 분석의 결과, Cinnamoyl 에스테르화도와 sensitivity의 관계 및 증감제의 농도와 sensitivity의 관계에 대하여 발표된 실험 data는 윗식을 만족시키므로 가정한 반응기구에 대한 뒷받침을 얻었다.

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MONOTONICITY PROPERTIES OF THE GENERALIZED STRUVE FUNCTIONS

  • Ali, Rosihan M.;Mondal, Saiful R.;Nisar, Kottakkaran S.
    • 대한수학회지
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    • 제54권2호
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    • pp.575-598
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    • 2017
  • This paper introduces and studies a generalization of the classical Struve function of order p given by $$_aS_{p,c}(x):=\sum\limits_{k=0}^{\infty}\frac{(-c)^k}{{\Gamma}(ak+p+\frac{3}{2}){\Gamma}(k+\frac{3}{2})}(\frac{x}{2})^{2k+p+1}$$. Representation formulae are derived for $_aS_{p,c}$. Further the function $_aS_{p,c}$ is shown to be a solution of an (a + 1)-order differential equation. Monotonicity and log-convexity properties for the generalized Struve function $_aS_{p,c}$ are investigated, particulary for the case c = -1. As a consequence, $Tur{\acute{a}}n$-type inequalities are established. For a = 2 and c = -1, dominant and subordinant functions are obtained for the Struve function $_2S_{p,-1}$.

Chiral [Iminophosphoranyl]ferrocenes: Synthesis, Coordination Chemistry, and Catalytic Application

  • Co, Thanh Thien;Shim, Sang-Chul;Cho, Chan-Sik;Kim, Dong-Uk;Kim, Tae-Jeong
    • Bulletin of the Korean Chemical Society
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    • 제26권9호
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    • pp.1359-1365
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    • 2005
  • A series of new chiral [iminophosphoranyl]ferrocenes, {${\eta}^5-C_5H_4-(PPh_2=N-2,6-R_2-C_6H_3)$}Fe{${\eta}^5-C_5H_3-1-PPh^2-2-CH(Me)NMe_2$} (1: R = Me, $^iPr$), {${\eta}^5{-C_5H_4-(PPh_2=N-2,6-R_2}^1-C_6H_3)$}Fe{${\eta}^5-C_5H_3-1-(PPh_2=N-2,6-R_2-C_6H_3)-2-CH(Me)R_2$} (2: $R^1\;=\;Me,\;^iPr;\;R^2\;=\;NMe_2$, OMe), and $({\eta}^5-C_5H_5)Fe${${\eta}^5-C_5H_4-1-PR_2-2-CH(Me)N=PPh_3$} (3:R = Ph, $C_6H_{11}$) have been prepared from the reaction of [1,1'-diphenylphosphino-2-(N,N-dimethylamino) ethyl]ferrocene with arylazides (1 & 2) and the reaction of phosphine dichlorides ($R_3PCl_{2}$) with [1,1'-diphenylphosphino-2-aminoethyl]ferrocene (3), respectively. They form palladium complexes of the type $[Pd(C_3H_5)(L)]BF_4$ (4-6: L = 1-3), where the ligand (L) adopts an ${\eta}^2-N,N\;(2)\;or\;{\eta}^2$-P,N (3) as expected. In the case of 1, a potential terdentate, an ${\eta}^2$-P,N mode is realized with the exclusion of the –=NAr group from the coordination sphere. Complexes 4-6 were employed as catalysts for allylic alkylation of 1,3-diphenylallyl acetate leading to an almost stoichiometric product yield with modest enantiomeric excess (up to 74% ee). Rh(I)-complexes incorporating 1-3 were also prepared in situ for allylic alkylation of cinnamyl acetate as a probe for both regio- and enantioselectivities of the reaction. The reaction exhibited high regiocontrol in favor of a linear achiral isomer regardless of the ligand employed.

Rod Migration into the Posterior Fossa after Harms Operation : Case Report and Review of Literatures

  • Chun, Hyoung-Joon;Bak, Koang-Hum;Kang, Tae-Hoon;Yi, Hyeong-Joong
    • Journal of Korean Neurosurgical Society
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    • 제47권3호
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    • pp.221-223
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    • 2010
  • C1 lateral mass and C2 pedicle (C1LM-C2P) fixation is a relatively new technique for atlantoaxial stabilization. Complications from C1LM-C2P fixation have been rarely reported. The authors report unilateral rod migration into the posterior fossa as a rare complication after this posterior C1-C2 stabilization technique. A 23-year-old man suffered severe head trauma and cervical spine injury after vehicle accident. He was unconscious for 2 months and regained consciousness. He underwent C1LM-C2P fixation for stabilization of type II odontoid process fracture described by Harms. The patient recovered without a major complication. Twenty months after operation, brain computed tomogram performed at psychology department for disability evaluation showed rod migration into the right cerebellar hemisphere. The patient had mild occipital headache and dizziness only regarding the misplaced rod. He refused further operation for rod removal. To our knowledge, this complication is the first report regarding rod migration after Harms method. We should be kept in mind the possibility of rod migration, and C1LM-C2P fixation should be performed with meticulous technique and long-term follow-up.

에코나졸 나이트레이트의 구조 (The Structure of Econazole Nitrate)

  • 서일환;조성일;박권일
    • 한국결정학회지
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    • 제1권1호
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    • pp.14-18
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    • 1990
  • Econazole nitrate, 1-{2-[(4-chlorophenyl)methoxy]-2-(2,4-dichlorophenyl) ethy1}-1H-imidazole mono-nitrate, C18 H16 CI13 N3 O4의 단위세포 상수는 a=19.337(4) A, b=15.191(5) A c=7.601(3)A, β=91.72(2)μ V=2000.0A3 Do=1.49g/ml Dm=1.47g/ml, M=4.31cm-1 F(000)=912.0, 2T=298K,공간군은 P2₁/C이고 단사 정계이며 Z=4이다. λ=(Mo-Ka)=0.7107 A을 사용한 1330개의 Intensity data에 대해 최종 R값은 0.06이다. Econazole nitrate의 각 세 ring은 각각 평면이며 B,A,C ring순서로 층계를 이루고 있다. 반면에 Econazole의 A와 C ring은 거의 같은 평면에 누워 있으나 B ring 은 거의 같은 평면이며 B,A,C ring순서로 층계를 이루고 있다.반면에 Econazole의 A와 C ring은 거의 같은 평면에 누워있으나 B ring과는 약 60˚의 평면각을 이루고 있다. Nitrate의 O(*3)와 Imidaze의 N(2) 사이의 수소결합은 Econazole slt의 안정화에 기여한다.

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Pleurotus sajo-caju가 생산(生産)하는 효소(酵素)에 관한 연구(硏究)(I) -섬유소(纖維素) 분해(分解) 효소(酵素)의 생산(生産)에 관하여- (Studies on the Enzymes Produced by Pleurotus sajor-caju(I) -The Production of Cellulolytic Enzymes-)

  • 홍재식;엄태붕;정기태;이강배
    • 한국균학회지
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    • 제12권2호
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    • pp.59-64
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    • 1984
  • 볏짚배지(培地)에서 Pleurotus sajor-caju의 배양조건(培養條件)을 달리하여 섬유소분해효소(纖維素分解酵素) 생산(生産)에 미치는 영향(影響)을 검토(檢討)하여 다음과 같은 결과(結果)를 얻었다. 1) 효소생산(酵素生産)의 최적(最適) 수분함양(水分含量), pH 및 온도(溫度)는 $C_1-cellulase$가 60%, 7.0, $35^{\circ}C$ 이었고 $C_x-cellulase$는 60%, 5.0, $25^{\circ}C$이었으며 ${\beta}-glucosidase$는 60%, 7.0, $20^{\circ}C$이었다. 2) 균사배양기간(菌絲培養期間) 중에 광(光)을 조사(照射)하므로서 $C_1-cellulase$${\beta}-glucosidase$생산(生産)은 감소(減少)하였으나 $C_x-cellulase$$500{\sim}1,000\;lux$에서 오히려 증가(增加)되었다. 3) 배양기간(培養期間) 중에 $C_1-cellulase$가 감소(減少)하면 $C_x-cellulase$${\beta}-glucosidase$가 증가(增加)하는 상반관계(相反關係)를 나타내었다. 4) 부원료(副原料) 중에서 $C_1-cellulase$는 미강(米糠), $C_x-cellulase$는 면실박(綿實粕)과 미강(米糠), ${\beta}-glucosidase$는 대두박(大豆粕)과 어분(魚粉)을 첨가(添加)했을 때 가장 양호(良好)했으며 $C_1-cellulase$${\beta}-glucosidase$는 미강(米糠) 20%, $C_x-cellulase$ 10%는 첨가(添加)했을 때 양호(良好)하였다.

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