• 제목/요약/키워드: {\alpha}$

검색결과 24,684건 처리시간 0.044초

벤조-[f]-인돌-4, 9-디온 유도체의 합성 (Synthesis of -4,9-Dione Derivatives)

  • 이지영;서명은
    • 약학회지
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    • 제34권1호
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    • pp.15-21
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    • 1990
  • -4,9-dione derivatives were prepared from $2-chloro-3-({\alpha}-accetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ and 2-chloro-3-N-phenylamino-1,4-naphthoquinone. $2-Chloro-3-({\alpha}-acetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ was reacted with amines to give $2-amino-3-({\alpha}-acetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ derivatives. Subsequent treatment of $2-amino-3-({\alpha}-acetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ with sodium ethoxide gave -4,9-dione derivatives. When 2-chloro-3-N-phenylamino-1,4-naphthoquinone reacted with sodium ${\alpha}-cyano$ ethyl acetate, 2-amino-3-ethoxycarbonyl-N-phenyl--4,9-dione was obtained. However, with sodium diethyl malonate, not -4,9-dione but 2-chloro-3-bis-(methoxycarbonyl)-methyl-2H-3-N-phenylamino-1,4-naphthoquinone was obtained.

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우우 유청으로부터 분리한 $\alpha$-락트알부민의 기능적 특성 (Functional Properties of $\alpha$-Lactalbumin Separated from Bovine Whey)

  • 홍윤호
    • 한국축산식품학회지
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    • 제18권1호
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    • pp.9-18
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    • 1998
  • This study was performed to obtain a large quantity of $\alpha$-lactalbumin ($\alpha$-LA) from milk by an improved separation and purification method. Functional properties-solubility viscosity, emulsifying activity, foamability surface hydrophobicity and gelation-of the purified $\alpha$-LA were investigated, $\alpha$-LA was purified in a large quantity by DEAE-Sephacel chromatography using 0.15M NaCl in 20mM Tris-HCl buffer(pH 7.2), as an eluent. The yield and purity of the purified $\alpha$-LA were 23.6%, 92.5%, respect-ively. The solubility viscosity and emulsifying activity of the purified $\alpha$-LA were 92.2$\pm$2% 3.46$\pm$0.19 cP and 345$\pm$5.0m^2$-/g respecively. The foamability of $\alpha$ -LA was 762 after 5min whipping which was lower than that of WPC and showed decreasing tendency with whipping time. The relative surface hydrophobicity of the $\alpha$-LA was formed when a 10% $\alpha$-LA solution containing 100mM NaCl and 20 mM $CaCl_2$ was heated at 92$^{\circ}C$for 40min. The $\alpha$-LA gel showed 31.5 as hardness and showed low springiness and cohesiveness.

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The Origins of the Warm Ionized Medium/Diffuse Ionized Gas

  • 선광일
    • 천문학회보
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    • 제38권1호
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    • pp.48.1-48.1
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    • 2013
  • It is known that the diffuse $H{\alpha}$ emission outside of bright H II regions not only are very extended, but also can occur in distinct patches or filaments far from H II regions, and the line ratios of [S II] ${\lambda}6716/H{\alpha}$ and [N II] ${\lambda}6583/H{\alpha}$ observed far from bright H II regions are generally higher than those in the H II regions. These observations have been regarded as evidence against the dust-scattering origin of the diffuse $H{\alpha}$ emission (including other optical lines), and the effect of dust scattering has been neglected in studies on the diffuse $H{\alpha}$ emission. However, as opposed to the previous contention, the expected dust-scattered $H{\alpha}$ halos surrounding H II regions are, in fact, in good agreement with the observed $H{\alpha}$ morphology. We find that the observed line ratios of [S II]/$H{\alpha}$, [N II]/$H{\alpha}$, and He I ${\lambda}5876/H{\alpha}$ in the diffuse ISM accord well with the dust-scattered halos around H II regions, which are photoionized by late O- and/or early B-type stars. We also demonstrate that the $H{\alpha}$ absorption feature in the underlying continuum from the dust-scattered starlight ("diffuse galactic light") and unresolved stars is able to substantially increase the [S II]/$H{\alpha}$ and [N II]/$H{\alpha}$ line ratios in the diffuse ISM.

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Effect of Allopurinol on the Ethanol-induced Oxidative Stress : Mechanism of Allopurinol Action

  • Park, Min-Kyung
    • Preventive Nutrition and Food Science
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    • 제3권1호
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    • pp.48-55
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    • 1998
  • An acute ethanol load(50mmol/kg , i.p) resulted in an increase in peroxidation and a decrease in the levels of $\alpha$-tocopherol and ascorbate in rat cerebellum. Pretreatement with allopurinol(146$\mu$mol/kg, i.p) prevented the ethnol-induced increment in lipid peroxidation and decrease in $\alpha$-tocopherol content. However, the decrease of ascorbate was of greater magnitude when allopurinol was associated with ethanol. These results suggested that allopurinol. besides its action as a radical scavenger and xanthine oxidase inhibitor, might favor the regeneration of $\alpha$-tocopherol antioxidant acitviity was studied using ${\gamma}$-radiolysis in aerated ethanolic solutions. Even though allopurinol did not react by itself with $\alpha$-hydroxyethyl-peroxyl radicals [H3C-CH(OH)OO] , it enhance the $\alpha$-hydroxyethyl-peroxyl radical scavenging properties of $\alpha$tocopherol. The regeneration of $\alpha$-tocopherol from the $\alpha$-hydroxyethyl-peroxyl radical scavenging properties of $\alpha$-tocophero. The regeneration of $\alpha$-tocopherol from the $\alpha$-tocopherol radical by ascorbate remained as efficient in the presence of allopurinol as in its absence. The effects of allopurinol on the Vitamin E oxidation-reduction mechanism could be involoved in the beneficial effectof allopurinol on the biological cellular damages linked to free radical reactions.

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α형 반수석고를 치환한 모르타르의 응결 및 압축강도, 건조수축 특성 (Setting Time, Compressive Strength and Drying Shrinkage of Mortar with Alpha-Calcium Sulfate Hemihydrate)

  • 이계혁;김규용;이보경;신경수;남정수
    • 한국구조물진단유지관리공학회 논문집
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    • 제21권5호
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    • pp.117-124
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    • 2017
  • ${\alpha}$형 반수석고는 생산방법이 복잡하고, 대량 연속 생산이 곤란하며, 재료 단가가 높기 때문에 건설재료로써 활용범위가 크지 않았으나, 최근 화력발전소의 배연탈황석고를 활용하여 경제적으로 ${\alpha}$형 반수석고를 제조하는 기술이 실용화되고 있다. 이에 본 연구에서는 응결 시작 시간이 빠르고 재령 초기 팽창변형이 발생하는 ${\alpha}$형 반수석고의 특징에 주목하여, ${\alpha}$형 반수석고를 10, 20, 30 wt.% 치환한 보통포틀랜드시멘트 및 고로슬래그시멘트 모르타르를 제조한 후 응결 및 압축강도 특성, 건조수축을 검토하였다. 실험 결과, ${\alpha}$형 반수석고의 치환율이 증가할수록 보통포틀랜드시멘트 모르타르 및 고로슬래그시멘트 모르타르의 초결시간이 빨라지는 경향을 확인할 수 있었다. 또한, 보통포틀랜드시멘트 모르타르와 고로슬래그시멘트 모르타르 모두 ${\alpha}$형 반수석고의 치환율이 증가할수록 압축강도가 저하되는 경향을 보였으며, 보통포틀랜드 시멘트보다 고로슬래그시멘트에서 ${\alpha}$형 반수석고의 압축강도 발현이 유리한 것으로 나타났다. 한편, ${\alpha}$형 반수석고를 치환한 모르타르의 경우 ${\alpha}$형 반수석고의 혼입에 의해 생성된 에트링가이트 침상결정의 성장압에 의해 초기재령에서 수축변형이 저감되는 것을 확인할 수 있었으며, 초기 재령에서 수축변형의 억제 효과는 분명하지만, 재령이 지남에 따라 ${\alpha}$형 반수석고를 치환하지 않은 조건과 변형의 차이는 다시 감소하는 경향을 보였다. 따라서 ${\alpha}$형 반수석고를 모르타르에 적용할 경우 강도는 다소 저하하지만, 응결 촉진 및 수축변형 억제에 큰 효과가 있기 때문에 건설재료로써 활용 가치가 높을 것으로 판단된다.

말채나무 추출물의 ${\alpha}-amylase$ 저해 활성 (The Inhibitory Effect of Cornus walteri Extract Against ${\alpha}-amylase$)

  • 임채성;이춘영;김용무;이위영;이해익
    • Applied Biological Chemistry
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    • 제48권1호
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    • pp.103-108
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    • 2005
  • ${\alpha}-Amylase$ 저해제는 소장에서 전분의 소화를 저해하여 포도당의 흡수를 지연시킴으로써 혈당 조절 목적으로 이용된다. 따라서 본 연구에서는 ${\alpha}-amylase$ 저해제를 탐색할 목적으로 국내 자생 목본류 약 1400여종의 70% ethanol 추출액을 대상으로 ${\alpha}-amylase$ 저해제 분포를 검색하였다. 수종의 목본류에서 ${\alpha}-amylase$ 저해제가 분포하고 있음이 확인되었으며, 그 중 활성이 비교적 높은 말채나무 기원의 저해제를 대상으로 연구를 진행하였다. 기원별 효소에 따른 저해 활성도를 살펴보면 salivary와 pancreatic ${\alpha}-amylase$, 미생물 기원의 ${\alpha}-glucosidase$에는 탁월한 저해 활성을 보인 반면 돼지 기원의 ${\alpha}-glucosidase$ 저해제에 대해서는 매우 낮은 저해 활성을 보였다. ${\alpha}-Amylase$${\alpha}-glucosidase$의 kinetic을 분석하면 salivary와 pancreatic 두 효소에 모두 경쟁적 저해제로, 효모의 ${\alpha}-glucosidase$에는 비경쟁적과 반경쟁적의 혼합형 저해제로 나타났다. 또한 열과 산성에 대한 안정성을 확인한 결과 비교적 안정적인 것으로 나타났다. 본 추출물의 식이 섭취에 따른 혈당 강하 효과와 체중에 미치는 영향에서는 혈당과 체중 상승을 억제하는 효과가 확인되었고, mRNA수준에서 대퇴근 세포에 있어서 GLUT4의 발현이 증가됨을 확인하였다.

Electrophoretic Behaviors of α-Lactalbumin and β-Lactoglobulin Mixtures Caused by Heat Treatment

  • Lee, You-Ra;Hong, Youn-Ho
    • Asian-Australasian Journal of Animal Sciences
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    • 제16권7호
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    • pp.1041-1045
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    • 2003
  • In order to study the reaction behaviors of bovine $\alpha$-lactalbumin ($\alpha$-La), $\beta$-lactoglobulin ($\beta$-Lg), and their mixtures during heat treatment, samples were analyzed using native-polyacrylamide gel electrophoresis (Native-PAGE), sodium dodecylsulfate (SDS)-PAGE, and two-dimensional (2-D)-PAGE. The electrophoresis demonstrated that the loss of native-$\alpha$-La increased as temperature increased, and that the loss of apo-$\alpha$-La was slightly higher than that of holo-$\alpha$-La. The tests also showed that during heat treatment, a mixture of $\alpha$-La and $\beta$-Lg was less stable than $\alpha$-La alone. As such, it was assumed that $\beta$-Lg induced holo-$\alpha$-La to be less stable than apo-$\alpha$-La during heat treatment. The reaction behavior of $\alpha$-La (holo-, apo-form) during heat treatment showed similar patterns in the 2-D-PAGE electropherogram, but the mixture of $\alpha$-La and $\beta$-Lg created new bands. In particular, the results showed a greater loss of native $\alpha$-La in the holo-$\alpha$-La and $\beta$-Lg mixture than in the apo-$\alpha$-La and $\beta$-Lg mixture. Thus, it can be concluded that the holo-$\alpha$-La and $\beta$-Lg mixture was more intensively affected by heat treatment than other samples, and that free sulphydryl groups took part in the heat-induced denaturation.

폐암 환자에서의 폐엽절제술 전후의 혈청 Alpha 1-Proteinase Inhibitor의 변화 (Pre- and Postoperative Changes of Serum Levels of Slpha 1-proteinase Inhibitor in Patients with Bronchogenic Cancer)

  • 이재성
    • Journal of Chest Surgery
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    • 제28권3호
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    • pp.221-227
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    • 1995
  • Malignancy is one of the several exogenous and endogenous factors that increase serum alpha 1-PI. In fact, serum levels of alpha 1-PI were significantly elevated in the patients with the nonresectable bronchogenic cancer. the purpose of this work was to determine if the immediate postoperative change of serum alpha 1-PI level following tumor resection relates to the patient`s postoperative course. Clinical experimental study was carried out to investigate the postoperative changes of serum alpha 1-PI level following operation for 20 cases of bronchogenic cancer and 10 cases of control, nephrectomy patients Alpha 1-PI concentrations in serum was quantitated by use of radial immunodiffusion technique.The results were as follows ; Preoperative serum level of alpha 1-PI was significantly elevated in patients with bronchogenic cancers [p < 0.001 , when compared to normal control levels. Immediate postoperative serum alpha 1-PI level was significantly increased in patients with bronchogenic cancer [p < 0.05 , but slightly decreased at control groups. The peak serum level of alpha 1-PI was the postoperative three days, and then gradually decreased at the 5, 9, 14 days, but slightly elevated comparing to preoperative alpha 1-PI levels. Serum alpha 1-PI level in patients with adenocarcinoma was elevated, when compared to squamous cell carcinoma, but not significantly. According to the stages of the bronchogenic cancer, each levels of the serum alpha 1-PI were slightly different, but the whole postoperative changes were the general similarity. There were no significant difference in changes of the serum alpha 1-PI level, according to the operative procedures. As the alpha 1-PI is acute reactant, that it was required at the reoperative state of the bronchogenic cancer and rapid response, consumption or requirement were occurred, postoperatively. Therefore, alpha 1-PI can be perioperative indicator for the evaluation of the bronchogenic cancer.

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$\alpha$-tocopherol의 항산화작용에 미치는 인삼사포닌분획의 영향 (The Effect of Ginseng Saponin Fraction on Antioxidant Activity of $\alpha$-Tocopherol)

  • 주충노;곽한식
    • Journal of Ginseng Research
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    • 제12권2호
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    • pp.128-134
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    • 1988
  • 인삼 사포닌 분획이 $\alpha$-tocopherol의 항산화작용에 미치는 영향을 시헌관내 실험과 동물실험으로 관찰하였다. 흰쥐 (Wister, 수컷, 180~200g)의 간 미크로좀 분획을 $Fe^{3+}$, NADPH, ADP, $\alpha$-tocopherol($50{\mu}M}$), 인삼 사포닌 분획(최종농도 $10^{-4}$%, 대조군은 사포닌 분획 대신 같은 부피의 물)을 함유한 혼합물에서 반응을 진행시키고 생성된 malondialdehyde를 분석한 결과, 사포닌은 $\alpha$-tocopherol의 항산화작용을 상승적으로 증가시켰다. 인삼 saponin 분획이 함유된 $\alpha$-tocopherol의 alcohol용액을 쥐에게 경구투여한 후 적당 시간 후에 간에서의 과산화수소량을 분석하여 대조군과 비교한 결과, 인삼 saponin 은 $\alpha$-tocopherol의 흡수를 촉진하므로서 $\alpha$-tocopherol의 항산화활성이 더욱 효율적으로 일어나게 하는 것으로 해석된다.

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홉프의 재배환경과 개화후 일수에 따른 $\alpha$-acid 함량 변화 (Influence of Days after Flowering and Cultural Environments on Changes of Alpha-Acid Content in Hops (Humulus lupulus L.))

  • 박경열;이동우;민인기
    • 한국작물학회지
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    • 제32권1호
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    • pp.97-102
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    • 1987
  • 홉프의 개화후 경과일수와 재배지 표고 및 연차간 기상 변화에 따른 $\alpha$-acid 함량의 변이를 구명하고 진행한 시험 결과를 요약하면 다음과 같다. 1. 홉프 $\alpha$-acid 함량은 개화후 50일경부터 70일경까지 최대에 달하였으며, 개화후 61일에 6.895%로써 최대치를 나타내었다. 2. 수확기에 따른 $\alpha$-acid 함량양은 표고가 낮은 130m이하에서는 수확기간에 미미한 변화를 나타내냈으나 그 이상의 표고에서는 8월 11일부터 15일경까지 수확한 것에서 타 수확기 보다 높았다. 3. $\alpha$-acid 함량이 가장 높은 표고는 190-260m이었고, 이보다 표고가 높거나 낮을수록 $\alpha$-acid 함량은 감소되었으며 표고 130m이하에서 가장 낮았다. 4. $\alpha$-acid 함량은 매년 정규분포를 나타내었으며, 동일 연도의 표고별 차이보다 동일 표고별 연차간 차이가 컸으며, 동일 연도내 표본간 CㆍV는 7.30~7.83%에 비하여 연차간 CㆍV는 19.26%로서 연차각 변이가 심하였다. 5. $\alpha$-acid 함량은 7월 하순의 최고기온과는 고도의 정상관, 평균기온과 일조시수와는 정상관, 강수양과는 부의 상관이 있었다. 6. 홉프의 생종화 수량과 $\alpha$-acid 함량은 유의한 정상관이 있었다.

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