• 제목/요약/키워드: 22

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A Steroselective Synthesis of (22R, 23R)-Methylenecholesterol

  • Kim, Deuk-Joon
    • Archives of Pharmacal Research
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    • 제15권4호
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    • pp.374-375
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    • 1992
  • The marine sterol (22R, 23R)-methylenecholesterol 1 has been synthesized from readily available C-22 steroidal ester 2 utilizing an intermolecular acyclic ester enolate alkylation as the key step.

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F-22 Raptor 개발 현황(3)

  • 임종춘
    • 국방과기술
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    • 10호통권224호
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    • pp.68-75
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    • 1997
  • F-22기는 지난 4월 9일 출고되어 전세계의 시선을 받은바 있으며 5월 최초의 시험비행을 하였다. 미 공군은 2010년까지 438대의 F-22 전투기를 구매하여 F-15기를 대체할 계획이었으나, 국방예산의 제약때문에 국방현대화 계획의 조정이 불가피할 것으로 보여 F-22기도 350대 이하로 감소될 가능성이 크다.

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A 24 kDa Excretory-Secretory Protein of Anisakis simplex Larvae Could Elicit Allergic Airway Inflammation in Mice

  • Park, Hye-Kyung;Cho, Min-Kyoung;Park, Mi-Kyung;Kang, Shin-Ae;Kim, Yun-Seong;Kim, Ki-Uk;Lee, Min-Ki;Ock, Mee-Sun;Cha, Hee-Jae;Yu, Hak-Sun
    • Parasites, Hosts and Diseases
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    • 제49권4호
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    • pp.373-380
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    • 2011
  • We have reported that a 24 kDa protein (22U homologous; As22U) of Anisakis simplex larvae could elicit several Th2-related chemokine gene expressions in the intestinal epithelial cell line which means that As22U may play a role as an allergen. In order to determine the contribution of As22U to allergic reactions, we treated mice with 6 times intra-nasal application of recombinant As22U (rAs22U). In the group challenged with rAs22U and ovalbumin (OVA), the number of eosinophils in the bronchial alveolar lavage fluid (BALF) was significantly increased, as compared to the group receiving only OVA. In addition, mice treated with rAs22U and OVA showed significantly increased airway hyperresponsiveness. Thus, severe inflammation around the airway and immune cell recruitment was observed in mice treated with rAs22U plus OVA. The levels of IL-4, IL-5, and IL-13 cytokines in the BALF increased significantly after treatment with rAs22U and OVA. Similarly, the levels of anti-OVA specific lgE and lgG1 increased in mice treated with rAs22U and OVA, compared to those treated only with OVA. The Gro-${\alpha}$ (CXCL1) gene expression in mouse lung epithelial cells increased instantly after treatment with rAs22U, and allergy-specific chemokines eotaxin (CCL11) and thymus-and-activation-regulated-chemokine (CCL17) gene expressions significantly increased at 6 hr after treatment. In conclusion, rAs22U may induce airway allergic inflammation, as the result of enhanced Th2 and Th17 responses.

R22의 대체냉매를 사용한 공기조화기의 성능 시뮬레이션 (Cycle Simulation of the Air-Conditioner Using Alternatives to R22)

  • 장세동;노승탁
    • 설비공학논문집
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    • 제6권1호
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    • pp.47-53
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    • 1994
  • Cycle simulation of the air-conditioner was carried out using a number of candidate alternatives to R22;R32/R125/R134a(30/10/60, by mass percent), R32/R125/R134a(10/70/20), R32/R134a(25/75), R32/R134a(30/70), R32/R125(60/40), R290(propane) and R134a. In this study, we considered only the basic parts of the air-conditioner such as the compressor, the evaporator, the condenser and the capillary tube, for the purpose of analysis. The performance characteristics of alternatives considered here were examined by comparing with the case using R22 at the constant volumetric flow rate condition. The results of our analysis revealed that the use of refrigerant mixtures, R32/R134a(30/70) and R32/R125/R134a(30/10/60), was appropriate for the alternatives to R22 in view of the cooling capacity and the COP. For the case of using R134a and R290, the COP was observed to increase under the same volumetric flow rate condition, but the cooling capacity was substantially decreased. Therefore the use of R134a and R290 should be accompanied with increasing considerably the size of compressor in order to maintain the same cooling capacity of R22.

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혈청 농도가 다제내성 억제제 BIBW22의 nucleoside 수송에 미치는 영향 (Effect of Serum Concentration on Inhibition of Nucleoside Transport by Multidrug Resistance Inhibitor BIBW22)

  • 이동권
    • Biomolecules & Therapeutics
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    • 제3권2호
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    • pp.116-121
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    • 1995
  • Some multidrug resistance inhibitors have been known to be influenced by the serum concentration. In this study, effect of serum concentration on inhibition of nucleoside transport by BIBW22, a new multidrug resistance inhibitor derived from dipyridamole (DPM), was studied. When 5% or 100% (v/v) of fetal bovine serum (FBS) was contained in the culture, DPM dose for which nucleoside transport was inhibited by 50% (lD$_{50}$) was 0.42 $\mu$M or 1.17 $\mu$M, respectively. BIBW22 also showed the same trend as DPM did in response to increase of FBS concentration. However, ID$_{50}$ value for DPM in the absence or presence of human plasma was 0.007 $\mu$M or 1.02 $\mu$M respectively showing 145 times increase of ID$_{50}$ value. ID$_{50}$ value for BIBW22 in the presence of human plasma was 0.028 $\mu$M showing only 5 times increase in ID$_{50}$ value. This result suggests that potency of BIBW22 was much less affected by the plasma concentration and BIBW22 could be a good candidate for a clinical use in multidrug resistance treatment.treatment.

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잿빛 곰팡이병의 미생물학적 제어 (Biological Control of Blue Mold by Microorganism)

  • 조정일;조자용;안병렬
    • 한국유기농업학회지
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    • 제8권3호
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    • pp.121-130
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    • 2000
  • 사과 저장중에 발생하는 푸른곰팡이병원균에 대한 길항미생물을 찾기 위하여 자연계로부터 유용미생물을 분리하여 Penicillum expansum에 대한 길항력 검정과 동정하였다. 자연계로부터 얻은 3,000여종의 미생물중에서 푸른곰팡이병원균에 대하여 길항력이 우수한 미생물을 1차적으로 11종 선발하였으며, 이중에서 가장 길항력이 뛰어난 미생물을 치종적으로 KB22를 선발하였다. 길항력이 우수한 KB22의 형태적 성질, 배양적 특성 및 생리 생화학적 성질 등을 조사하여 비교 검토한 결과 Bacillus subtilis와 유사한 균으로 동정되었다. 분리한 길항균 Baillus subtilis KB22는 푸른곰팡이병에 대한 55.9%의 높은 생장억제력을 보였으며, 한천배지에서 Penicillum expansum 접종 후 길항균처리와 열처리한 길항균배양액을 처리하였을 때 각각90%와 15%이상 길항력을 보여주었다.

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3성분 혼합냉매 R-407c의 수평 마이크로핀관내 응축압력강하에 관한 연구 (Study on the pressure drop of ternary refrigerant R-407c during condensation inside horizontal micro-fin tubes)

  • 정재천
    • Journal of Advanced Marine Engineering and Technology
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    • 제22권2호
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    • pp.210-218
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    • 1998
  • Experimental results for forced convection condensationof Refrigerant-22 and ternary Refrigerant-407c(HFC-32/125/134a 23/25/52 wt%) considered as a substitute R-22 inside horizontal micor-fin tubes are presented. The test section was horizontal double-tubed counterflow condenser with a length 4000 mm micro-fin tube having 9.53 mm OD., 0.2 mm fin height and 60 fins. The refrigerants R-22 and R-407c were cooled by a coolant circulated in a surrounding annulus. The range of parameters of mass velocity was varied from 102.1 to 301.0kg/($\textrm{m}^{2}.s$) with inlet quality 1.0. Both refrigerant R-22 and its alternative refrigerant R-407c were tested within the same range of parameters. At the given experimental conditions for R-22 and R-407c the pressure drops for R-407c were considerably higher than those for R-22 at micro-fin tubes. Over the mass velocity range tested the PF(penalty factor)was lower than the increasing ratio of heat transfer area by fins. Based on the data correlation was proposed for predicting the frictional pressure drops for R-22 and R-407c for a duration of condensation inside a horizontal micro-fin tube.

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