• 제목/요약/키워드: 17B

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SAR 측정 및 교정기술에 관한 한국-일본 공동 연구

  • 김기회;오학태
    • 한국전자파학회지:전자파기술
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    • 제17권4호
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    • pp.3-10
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    • 2006
  • 한국의 전파연구소와 일본의 정보통신연구기구는 휴대전화와 같은 이동통신기기로부터 방사되는 전자파가 인체에 흡수되는 에너지 정도를 측정하는 전자파 흡수율(SAR) 평가에 대한 오차 연구를 공동으로 수행하고 있다. 본 논문에서는 동종의 SAR 시스템에서 프로브, 교정용 도파관 및 기준 다이폴 안테나를 상호 교체하여 교정하여 프로브의 교정인자를 구하고 유효성 검사를 통하여 교정 오차를 검증하였다. 프로브 교정에 대한 상호 오차는 0.2 dB 이하의 결과를 얻었으며, 유효성 오차는 최대 0.28 dB를 얻었다. 그러나 SAR 외삽 알고리즘이 다를 경우는 최대 0.48 dB의 상대 오차를 보였다.

A SURVEY OF BLOCH CONSTANTS

  • An, Jong-Su
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제2권1호
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    • pp.17-24
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    • 1995
  • We begin with a brief survey of some of the known results dealing with Bloch constants. Bloch's theorem asserts that there is a constant B$\_$1.C/(1, 0) such that if f is holomorphic in the open unit disk D and normalized by │f'(0)│$\geq$1, then the Riemann surface of f contains an unramified disk of radius at least B$\_$1.C/(1, 0) (see[7,p.14]).(omitted)

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ON A HYPERSURFACE OF THE FIRST APPROXIMATE MATSUMOTO SPACE

  • Lee, Il-Yong;Jun, Dong-Gum
    • East Asian mathematical journal
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    • 제17권2호
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    • pp.325-337
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    • 2001
  • We consider the special hypersurface of the first approximate Matsumoto metric with $b_i(x)={\partial}_ib$ being the gradient of a scalar function b(x). In this paper, we consider the hypersurface of the first approximate Matsumoto space with the same equation b(x)=constant. We are devoted to finding the condition for this hypersurface to be a hyperplane of the first or second kind. We show that this hypersurface is not a hyper-plane of third kind.

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Novel Synthesis of Imidazo[1,2-b]Pyrazoles and Their Fused Derivatives

  • Sherif, Sherif-M.;Hussein, Abdel-HaLeem-M.;El-kholy, Yehya-M.
    • Archives of Pharmacal Research
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    • 제17권5호
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    • pp.298-303
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    • 1994
  • 4-Arylazo-1H-pyrazol-3, 5-idimines 1a-c reacted with bromomalononitrile (2) to yield the corresponding imidazo[1, 2-b]pyrazoles 3a-c. The latter reacted with some active methylene compounds and with .alpha.-cinnamonitriles to afford the corresponding pyrazoloimidazopyridines 6, 8, 9 and 15, respectively. Compounds 3 reacted with each of formic acid, formamide, trichlo-roacetonitrile and with guanidine to yield the corresponding pyrazoloimidazopyrimidines 16-19 respectively.

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Cancer Activation and Polymorphisms of Human Cytochrome P450 1B1

  • Chun, Young-Jin;Kim, Donghak
    • Toxicological Research
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    • 제32권2호
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    • pp.89-93
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    • 2016
  • Human cytochrome P450 enzymes (P450s, CYPs) are major oxidative catalysts that metabolize various xenobiotic and endogenous compounds. Many carcinogens induce cancer only after metabolic activation and P450 enzymes play an important role in this phenomenon. P450 1B1 mediates bioactivation of many procarcinogenic chemicals and carcinogenic estrogen. It catalyzes the oxidation reaction of polycyclic aromatic carbons, heterocyclic and aromatic amines, and the 4-hydroxylation reaction of $17{\beta}$-estradiol. Enhanced expression of P450 1B1 promotes cancer cell proliferation and metastasis. There are at least 25 polymorphic variants of P450 1B1 and some of these have been reported to be associated with eye diseases. In addition, P450 1B1 polymorphisms can greatly affect the metabolic activation of many procarcinogenic compounds. It is necessary to understand the relationship between metabolic activation of such substances and P450 1B1 polymorphisms in order to develop rational strategies for the prevention of its toxic effect on human health.

Cyclooxygenase-2 as a Molecular Target for Cancer Chemopreventive Agents

  • Surh, Young-Joon
    • Toxicological Research
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    • 제17권
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    • pp.89-96
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    • 2001
  • Recently, considerable attention has been focused on the role of cyclooxygenase-2 (COX-2) in the carcinogenesis as well as in inflammation. Improperly overexpressed COX-2 has been observed in many types of human cancers and transformed cells in culture. Thus, it is conceivable that targeted inhibition of abnormally or improperly up-regulated COX-2 provides one of the most effective and promising strategies for cancer prevention. A ubiquitous eukaryotic transcription factor, NF-kB is considered to be involved in regulation of COX-2 expression. Furthermore, extracellular-regulated protein kinase and p38 mitogen-activated protein (MAP) kinase appear to be key elements of the intracellular signaling cascades involved in NF-kB activation in response to a wide array of external stimuli. Certain chemopreventive phytochemicals suppress activation of NF-kB by blocking one or more of the MAP kinases, which may contribute to their inhibitory effects on COX-2 induction. One of the plausible mechanisms by which chemopreventive phytochemicals inhibit NF-kB activation involves suppression of degradation of the inhibitory unit I kB, which hampers subsequent translocation of p65, the functionally active subunit of NF-kB.

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$T_{b}$-$N_{HI}$ CORRELATION IN THE GALACTIC PLANE

  • Kim, Yong-Gi
    • Journal of Astronomy and Space Sciences
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    • 제17권1호
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    • pp.33-38
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    • 2000
  • Synchrotron emission at 408 MHz and HI column density have been used to find an evidence for the relationship between the Galactic magnetic field and the gas density. The observational data of the brightness temperature and HI column density, $T_b(408)\;and \;N_{HI}$, near the galactic plane between galactic longitudes $l=62^{circ}\;and\;l=250^{\circ}$ show a clear linear correlation of $T_b(408)=A(l,b)+B\;N_{HI}$, where A(l, b)is a background and forground radiation at the galactic coordinate. We found $(1.4{pm}0.3)10^{-21}$ for the slope B, which describes the strength of the syncrotron radiation from the HI cloud, and agrees with the value for the MIlky Way obtained by Beuermann et al. (1985). We conclude therefore that a well defined nonthermal corelates with the HI column density originating from this HI cloud.

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The Effects of Metal Compounds on the Phospholipid Metabolism in Bacillus subtilis;

  • Ma, Hye-Young;Jung, Kyung-Suk;Jang, Jae-Seon;Lee, Chong-Sam
    • 한국환경보건학회지
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    • 제23권2호
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    • pp.1-11
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    • 1997
  • Copper chloride 10 ppm, manganese chloride 100 ppm, nickel chloride 50 ppm을 각각 처리한 Bacillus subtilis를 배양하는 동안에 이들 세포에서 일어나는 인지질 생합성 및 지방산 조성의 변화를 대조구와 비교하여 분석하였다. 세포의 생장과 phosphatidylethanloamine, phosphatidylcholine, phosphatidylglycerol, cardilolpin은 대조구에 비해 금속 화합물 처리구에서 저해되었는데 copper chloride가 가장 큰 억제 효과를 나타내었다. 그러나 phosphatidylinositol은 금속화합물의 영향을 받지 않았다. 인지질 생합성에 이용된 주요 지방산은 대조구에서는 palmitic acid(평균 19.00%)와 stearic acid(평균 9.58%)로 나타났다. 그러나 copper chloride 처리구는 palmitic acid(평균 17.38%)와 oleic acid(평균 15.99%)가 인지질 생합성에 이용된 주요 지방산이었고, manganese chloride 처리구는 palmitic acid(평균 15.00%)와 myristic acid(평균 14.24%), nickel chloride 처리구는 oleic acid(평균 17.87%)와 stearic acid(평균 13.78%)가 인지질 형성에 이용되었다.

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Factors Predicting Fecal Occult Blood Testing among Residents of Bushehr, Iran, Based on the Health Belief Model

  • Dashdebi, Kamel Ghobadi;Noroozi, Azita;Tahmasebi, Rahim
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권sup3호
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    • pp.17-22
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    • 2016
  • Colorectal cancer is a major cause of mortality worldwide. Fecal occult blood testing has proven a very effective screening tool for early detection and mortality reduction. The aim of this study was to determine predictors factors related to fecal occult blood testing using the Health Belief Model method among residents of Bushehr, Iran. A cross sectional study was performed on a sample of 600 men and women more than 50 years of age. The sample was selected by a convenience method from patients referred to public and private laboratories throughout the city. Each subject filled out a questionnaire which was designed and developed based on Health Belief Model constructs. Statistical analysis was conducted using ANOVA, T-test, chi-square test, and logistic regression. Fecal occult blood tests were performed on 179 (29.8%) out of 600 subjects, of which 95 patients (58.1%) did a periodic examination test and 84 patients (46.9%) had a doctor's advice for testing. According to the logistic regression model, the perceived barriers (P=0.0, Exp(B)= 0.3), perceived benefits (P<0.01, Exp(B)= 1.9) and self-efficacy (P<0.01, Exp(B)= 1.6) were predictive factors related to occult blood testing among subjects. The results showed that reducing people's perception of barriers to testing, increasing perceived benefits of screening, and reinforcing self efficacy can have major effect in increasing the rate of fecal occult blood screening for colorectal cancer prevention.

Gastric Carcinoma: Recent Trends in Diagnostic Biomarkers and Molecular Targeted Therapies

  • Majeed, Wafa;Iftikhar, Asra;Khaliq, Tanweer;Aslam, Bilal;Muzaffar, Humaira;Atta, Komal;Mahmood, Aisha;Waris, Shahid
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권7호
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    • pp.3053-3060
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    • 2016
  • Gastric cancer is generally associated with poor survival rates and accounts for a remarkable proportion of global cancer mortality. The prevalence of gastric carcinoma varies in different regions of world and across teh various ethnic groups. On the basis of pathological assessment, gastric cancer can be categorized as intestinal and diffuse carcinomas. The etiology is diverse, including chemical carcinogen exposure, and high salt intake Helicobacter pylori also plays a vital role in the pathogenesis of certain gastric carcinomas. The development of gastric cancer involves various alterations in mRNAs, genes (GOLPH3, MTA2) and proteins (Coronins). miRNAs, Hsa-mir-135b, MiR-21, miR-106b, miR-17, miR-18a, MiR-21, miR-106b, miR-17, miR-18a and MiRNA-375, miRNA-195-5p are the latest diagnostic biomarkers which can facilitate the early diagnosis of gastric carcinomas. Recent development in the treatment strategies for gastric carcinoma include the introduction of monoclonal antibodies, TKI inhibitors, inhibitors of PDGFR ${\beta}$, VEGFR-1, VEGFR-2, Anti-EGFR and anti-HER2 agents which can be applied along with conventional therapies.