• 한국결정성장학회지
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• 제8권1호
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• pp.138-144
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• 1998

에탄올을 용매로 사용한 철질산염(Fe$(MO_3)_3{\cdot}9H_2O$) 용액의 가용매분해 및 중합반응을 거친후 $350^{\circ}C$의 온도로 열처리를 하여 0.5$\alpha$m이하의 크기를 갖는 $\alpha$-$Fe_2O_3$ 미분말을 합성하였다. 반응시간에 따른 pH 변화와 적외선 분광 분석을 통해 용액내의 반응을 규명하였으며, 열분석(DSC), X-선 회절분석 및 적외선 분광(FT-IR) 분석을 통해 $\alpha$-$Fe_2O_3$가 형성되는 분해과정에 대해 분석하였다. 또한 반응온도와 철질산염의 농도를 변화시켜 각각 $\alpha$-$Fe_2O_3$분말의 입자크기에 미치는 영향을 조사하였다.

• 한국식품영양학회지
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• 제10권3호
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• pp.360-364
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• 1997

멥쌀식혜에 Saccharomyces cerevisae를 가해 28$^{\circ}C$에서 10일간 발효시켜서 식혜주를 제조하였다. TLC 및 HPLC 분석 결과 발효에 따라 글루코오스는 하루, 말토오스는 4일, 말토트리오스는 6일까지만 존재하였다. 그러나, 분자량이 큰 말토올리고당과 한계덱스트린은 발효되지 않았다. 에탄올은 6.5%를 나타냈다. 식혜주의 아미노산 함량은 2.9$\mu$mol/ml, 단백질 함량은 457$\mu\textrm{g}$/ml를 나타냈다. pH는 3.67, 산도는 3.1ml를 나타냈다. 한계덱스트린은 1H-NMR로 분석 결과 식혜에 존재하는 것과 구조상 변화가 없었다. $\alpha$-1,4-결합에 대한 $\alpha$-1,6-결합의 비율도 5.6:1을 나타냈다. 관능검사 결과, 맛은 와인과 비슷하였다.

• 미생물학회지
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• 제36권2호
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• pp.112-118
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• 2000

Bacillus circulans KCT3004 유래의 호산성 $\alpha$-amylase 유전자가 pUC19을 vector로 하여 대장균 내에서 클로닝 되었다. 클로닝된 5.8kb Pst I DNA절편은 pUC19내에서의 삽입방향과는 무관하게 $\alpha$-amylans보다 약40배 정도의 높은 효소활성을 나타내었다. 본 연구에서 클로닝 및 발현된 효소의 최적 pH와 온도는 각각 pH 3.6 $45^{\circ}C$였으며, $40^{\circ}C$에서 1시간 동안의 사전 열처리에도 활성의 감소를 일으키지 않았다. 이 효소는 SDS-PAG와 zymogram을 통해 분석해 본 결과 분자량은 약 55,000으로 추정되었으며 기질로 starch만을 가수분해하여 maltoriose 이상의 올리고당 분자들을 주로 생산할수 있었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권4호
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• pp.292-296
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• 2004

The recombinant soluble human tumor necrosis factor-alpha (hTNF-$\alpha$) was expressed in a yeast Saccharomyces cerevisiae and its cytotoxicity was evaluated. A cDNA encoding hTNF-$\alpha$ was placed under the control of two different promoters: a glyceraldehyde-3-phosphate dehydrogenase (GPD) promoter and a yeast hybrid ADH2-GPD promoter, consisting of alcohol dehydrogenase II (ADH2) and the GPD promoter. A Northern blot analysis revealed that, although variation in the expression level of hTNF-$\alpha$ existed among transformants, the higher expression was obtained with the GPD promoter. Expressed hTNF-$\alpha$ protein (rhTNF-$\alpha$) was successfully secreted into the culture medium, producing 2.5 mg per liter of culture filtrate, with no changes in cell growth. The bioassay for observing the cytotoxicity to the murine L929 fibroblast cell line, with serial dilution of rhTNF-$\alpha$, indicated that the secreted rhTNF-$\alpha$ was bioactive and its dose-response was improved eight to ten times over that of the E. coli-derived rhTNF-$\alpha$.

• 미생물학회지
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• 제36권2호
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• pp.136-141
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• 2000

소양호에서 수온, 엽록소$\alpha$, pH 그리고 DOC의 농도가 세균군집에 미치는 영향을 파악하였다. 이 연구에서는 fluorescent in situ hybridization(FISH) 방법을 사용하기 1998년 4월부터 5월까지 세균군집구조를 조사하였고 이 시기 환경요인과 세균군집간의 상관성 분석을 실시하기 위해 수온, 엽록체$\alpha$, pH, DOC의 측정도 함께 수행하였다. 또한 환경요인과 세균군집간의 상관성 분석을 실시하기 위해 통계프로그램(SPSS)을 이용하였다. 그 결과 소양호에서 DOC, 엽록체$\alpha$, pH와 온도가 다중선형희귀직선상 설명가능정도가 약 43~58%정도로 나타났으며, 세균군집변화의 약 50%정도가 본 조사 이외의 환경요인에 영향을 받은 것으로 나타났다. $\alpha$-group은 DOC가 증가할수록 감소하여 DOC와 음의 상관관계를 보였고 , ${\gamma}$-group은 엽록소 $\alpha$농도와 음의 상관관계를 나타내었다. $\beta$-Cytophaga-Flavobacterium group 의 경우 수온과 뚜렷한 양의 상관성이 있는 것으로 나타났다. 또한 $\alpha$-group과 Cytophaga-Flavobacterium group은 pH와 양의 상관관계를 보였다. 이처럼 소양호의 세균군집은 계절에 따른 여러 가지 수 환경요인의 변화에 의해 다양하게 변화하였다.

• Tuberculosis and Respiratory Diseases
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• 제80권1호
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• pp.60-68
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• 2017

Background: Mucus hypersecretion from airway epithelium is a characteristic feature of airway inflammatory diseases. Tumor necrosis factor ${\alpha}$ (TNF-${\alpha}$) regulates mucin synthesis. Glucocorticoids including mometasone fuorate (MF) have been used to attenuate airway inflammation. However, effects of MF on mucin production have not been reported. Methods: Effects of MF and budesonide (BUD) on the phorbol-12-myristate-13-acetate (PMA)-induction of mucin and TNF-${\alpha}$ in human airway epithelial cells (NCI-H292) were investigated in the present study. Confluent NCI-H292 cells were pretreated with PMA (200 nM) for 2 hours. Subsequently, the cells were stimulated with MF (1-500 ng/mL) or BUD (21.5 ng/mL) for 8 hours. Dexamethasone ($1{\mu}g/mL$) was used as the positive control. Real-time polymerase chain reaction was used to determine MUC2 and MUC5AC mRNA levels. The level of total mucin, MUC2, MUC5AC, and TNF-${\alpha}$ in culture supernatants were measured using enzyme-linked immunosorbent assay. Results: MF and BUD significantly suppressed MUC2 and MUC5AC gene expression in PMA-stimulated NCI-H292 cells. The inhibitory effects of the two steroid drugs were also observed in the production of total mucin, MUC2 and MUC5AC proteins, and TNF-${\alpha}$. Conclusion: Our findings demonstrated that MF and BUD attenuated mucin and TNF-${\alpha}$ production in PMA-induced human airway epithelial cells.

• 한국식품과학회지
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• 제20권1호
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• pp.79-84
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• 1988

대두(大豆)중에 존제하는 장내(腸內) 가스 발생인자인 raffinose와 stachyose의 제거에 이용될 수 있는 Aspergillus niger의 ${\alpha}$-galactosidase는 Czapeck-Dox 액체배지와 밀기울 배지에서 5일간 배양하였을 때 효소생성이 제일 높았다. Czapeck-Dox 액체배양에서 raffinose와 $NaNO_3$가 효소생산에 가장 효과적인 탄소원과 질소원으로 나타났으며 밀기울 배양에서는 질소원 또는 탄소원의 첨가효과가 없었다. 생성된 조효소(組酵素)용액의 작용 최적 pH는 4.0-5.0, 안정도 최적 pH는 3.5-6.5, 최적온도는 $40-50^{\circ}C$ 였다. 합성기질인 p-nitrophenyl-${\alpha}$-D-galactoside에 대한 Michaelis상수는 0.42mM, 최대반응속도는 152${\mu}moles$ substrate/min/kg (고체배지)이었다. $HgCl_2$는 강력한 비경쟁 저해제로 작용하였고 p-chloromercuribenzoate는 낮은 농도에서 경쟁 저해제로 작용하였다. 조효소 용액은 raffinose와 stachyose를 완전 분해하여 단당류 만을 생성하였다.

• 한국세라믹학회지
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• 제34권11호
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• pp.1187-1197
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• 1997

Dry gel composed of primary particles more homogeneous than starting boehmite powder was prepared by dispersing and gelling the boehmite powder. The transformation temperatures of boehmite powder, dry gel seeded with 0, 1, 3, 5 wt% $\alpha$-Al2O3, and ball milled gel were 1192$^{\circ}C$, 1184$^{\circ}C$, 1141$^{\circ}C$, 1119$^{\circ}C$, 1117$^{\circ}C$, and 1106$^{\circ}C$, respectively. Sintering behavior of dry gel without seed was similar to that of boehmite powder, but the sintered density of dry gel was improved as much as 10%~15% than boehmite powder. In the case of dry gel seeded with 5 wt% $\alpha$-Al2O3, sintering behavior was much improved. The relative density of the gel seeded with 5 wt% $\alpha$-Al2O3 was 96% when sintered at 140$0^{\circ}C$ for 1h. On the other hand, ball milling of the non-seeded sol for 48h resulted in the relative density of 97% when sintered at 130$0^{\circ}C$ for 1h. The size and amount of $\alpha$-Al2O3 particles added by ball milling were 0.107 ${\mu}{\textrm}{m}$ and 0.5 wt%.

• 한국가축번식학회지
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• 제9권1호
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• pp.31-35
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• 1985

This study was carried out with 46 cows to investigate the ovarian response to the administration of PMSG, PGF2$\alpha$ and hCG, and the developmental stage of embryos recovered. Superovulation was induced by the injection of 2,000IU to 3,000IU PMSG on the days of 7-13 of the estrus cycle followed 48 hours later by the injection of 22.5mg PGF2$\alpha$. Of 29 cows treated with 3,000IU PMSG and 22.5mg PGF2$\alpha$ 18 cows were given 2,000IU hCG at the onset and 7 after artificial insemination. The results obtained were summarized as follows; 1. The number of developed follicles per cow after an injection of 2,000, 2,500, 3,000IU of PMSG and 3,000 PMSG-2,000IU hCG in combination with 22.5mg PGF2$\alpha$ were 12.6, 19.6, 21.5 and 29.3, respectively. This result indicated that the no. of developed follicles per cow was increased according to the increase of PMSG dosage and the combination with hCG injection. 2. The highest number of ovulation was 17.1 in cows treated with PMSG-hCG and the number of matured corpus luteum was increase as the dosage of PMSG was higher. 3. Ovulation rate from cows treated with 2,500IU PMSG was 71.0% and this reulst was higher than the average of ovulation rate (59.3%). 4. Average recovery rate was 36.8%(232/631), and the number of ova per cow was 5.0. 5. Of 232 recovered embryos, the number of morulae and blastocysts were 76 (32.8%) and 83 (35.8%), respectively. 6. 28.4% of total recovered embryos was abonormal morphologically.

• The Korean Journal of Physiology and Pharmacology
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• 제21권5호
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• pp.495-507
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• 2017

The effect of clonidine administered intrathecally (i.t.) on the mortality and the blood glucose level induced by sepsis was examined in mice. To produce sepsis, the mixture of D-galactosamine (GaLN; 0.6 g/10 ml)/lipopolysaccharide (LPS; $27{\mu}g/27{\mu}l$) was treated intraperitoneally (i.p.). The i.t. pretreatment with clonidine ($5{\mu}g/5{\mu}l$) increased the blood glucose level and attenuated mortality induced by sepsis in a dose-dependent manner. The i.t. post-treatment with clonidine up to 3 h caused an elevation of the blood glucose level and protected sepsis-induced mortality, whereas clonidine post-treated at 6, 9, or 12 h did not affect. The pre-treatment with oral D-glucose for 30 min prior to i.t. post-treatment (6 h) with clonidine did not rescue sepsis-induced mortality. In addition, i.t. pretreatment with pertussis toxin (PTX) reduced clonidine-induced protection against mortality and clonidine-induced hyperglycemia, suggesting that protective effect against sepsis-induced mortality seems to be mediated via activating PTX-sensitive G-proteins in the spinal cord. Moreover, pretreatment with clonidine attenuated the plasma tumor necrosis factor ${\alpha}$ ($TNF-{\alpha}$) induced by sepsis. Clonidine administered i.t. or i.p. increased $p-AMPK{\alpha}1$ and $p-AMPK{\alpha}2$, but decreased p-Tyk2 and p-mTOR levels in both control and sepsis groups, suggesting that the up-regulations of $p-AMPK{\alpha}1$ and $p-AMPK{\alpha}2$, or down-regulations of p-mTOR and p-Tyk2 may play critical roles for the protective effect of clonidine against sepsis-induced mortality.