• Title/Summary/Keyword: Protective effect.

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Measurement and Verification of Thermal Conductivity of Multilayer Thin Dielectric Film via Differential 3$\omega$ Method (차등 3$\omega$ 기법을 이용한 다층 유전체 박막의 열전도도 측정 및 검증)

  • Shin Sang-Woo;Cho Han-Na;Cho Hyung-Hee
    • 정보저장시스템학회:학술대회논문집
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    • 2005.10a
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    • pp.254-259
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    • 2005
  • In this study, measurement of thermal conductivity of multilayer thin dielectric film has been conducted via differential 3$\omega$ method. Also, verification of differential 3$\omega$ method has been accomplished with various proposed criteria. The target film for measurement is 300 nm silicon dioxide and this thin film is covered with various thicknesses of upper protective layer. The upper protective layer is inserted between the target film and the heater line for purpose of electrical insulator or anti-oxidation barrier since the target film may be a good electrical conductor or a well-oxidizing material. However, the verification of differential 3$\omega$ method has not been conducted. Thus we have shown that the measurement of thermal conductivity of thin films with upper protective layer via differential 3$\omega$ method is verified to be reliable as long as the proposed preconditions are satisfied. Experimental results show that the experimental errors tend to increase with aspect ratio between upper protective layer thickness and width of the heater line due to heat spreading effect.

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Measurement and Verification of Thermal Conductivity of Multilayer Thin Dielectric Film via Differential $3\omega$ Method (차등 $3\omega$ 기법을 이용한 다층 유전체 박막의 열전도도 측정 및 검증)

  • Shin, Sang-Woo;Cho, Han-Na;Cho, Hyung-Hee
    • Transactions of the Society of Information Storage Systems
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    • v.2 no.1
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    • pp.85-90
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    • 2006
  • In this study, measurement of thermal conductivity of multilayer thin dielectric film has been conducted via differential $3\omega$ method. Also, verification of differential $3\omega$ method has been accomplished with various proposed criteria. The target film for the measurement is 300 nm thick silicon dioxide which is covered with upper protective layer of various thicknesses. The upper protective layer is inserted between the target film and the heater line for purpose of electrical insulator or anti-oxidation barrier since the target film may be a good electrical conductor or a well-oxidizing material. Since the verification of differential $3\omega$ method has not been conducted yet, we have shown that the measurement of thermal conductivity of thin films with upper protective layer via differential $3\omega$ method is verified to be reliable as long as the proposed preconditions of the samples are satisfied. Experimental results show that the experimental errors tend to increase with aspect ratio between thickness of the upper protective layer and width of the heater line due to heat spreading effect.

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The Protective Effect of Paeoniae Radix Extract against 1-methyl-4-Phenylpyridium-induced Apoptosis on SK-N-MC Neuroblastoma Cells

  • Chae, Ki-Heon;Song, Yun-Kyung;Lim, Hyung-Ho
    • The Journal of Korean Medicine
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    • v.26 no.4
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    • pp.74-86
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    • 2005
  • Background: There are increasing neuro-degenerative disorders with aging. Paeoniae Radix(PR) possesses various pharmacological effects such as sedative, analgesic, anti-inflammatory, anti-stress and neuro-protective actions. Also antiaging and anti-cancer effects of PR were reported. Our purpose was to investigate whether PR is useful on the treatment of Parkinson's disease, one of the neuro-degenerative disorders. Objective: We investigated whether Paeonia Radix possesses a protective effect against 1-methyl-4 phenylpyridine(MPP+)-induced cytotoxicity in neuronal cells. Methods: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay, flow cytometry, DNA fragmentation assay, reverse transcription-polymerase chain reaction(RT-PCR), and Western blotting were performed on SK-N-MC neuroblastoma cells. Results: Cells treated with MPP+ exhibited several apoptotic features, while cells pre-treated with Paeonia Radix prior to MPP+ exposure showed s decrease in the occurrence of apoptotic features. Conclusions: These results suggest that Paeonia Radix may exert a protective effect against MPP+-induced apoptosis in SK-N-MC neuroblastoma cells.

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Protective Effect of Water Extract of Fraxinus Rhynchophylla Leaves on Acetaminophen-induced Nephrotoxicity in Mice and Its Phenolic Compounds

  • Jeon, Jeong-Ryae;Choi, Joon-Hyuk
    • Food Science and Biotechnology
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    • v.16 no.6
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    • pp.988-993
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    • 2007
  • The protective effect of the water extract of Fraxinus rhynchophylla leaves (FLE) was determined using an animal model of acetaminophen (AAP)-induced nephrotoxicity. The BALB/c male mice used in this study were divided into 3 groups; the normal, AAP-administered, and FLE-pretreated AAP groups. A single dose of AAP induced necrosis of renal tubules and congestion along with edema to a remarkable degree as observed by hematoxylin and eosin stain, and also increased the numbers of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL)-positive renal tubular epithelial cells. Blood urea nitrogen and plasma creatinine levels were determined to be significantly higher in the AAP group than in the normal group. However, FLE pretreatment resulted in an attenuation of renal tubule necrosis. Regeneration and dilatation of renal tubules were noted, and the numbers of TUNEL-positive cells were reduced in the FLE-pretreated groups. In an effort to detect the bioactive compounds exerting protective effects in FLE, the analysis of phenolic compounds via gas chromatography/mass spectrometry (GC/MS) were performed, and identified esculetin and esculin. The present study indicates that these compounds may exert a protective effect against AAP-induced nephrotoxicity.

Antioxidant and Neuronal Cell Protective Effects of Eugenia caryophyllata Thunb. by Extraction Solvent (용매별 정향 추출물의 항산화 및 신경세포 보호 효과)

  • Oh, Hee-Kyung
    • Journal of the Korean Society of Food Culture
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    • v.32 no.6
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    • pp.583-588
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    • 2017
  • This study examined the antioxidant and neuronal cell protective effects of the water and methanol extracts of Eugenia caryophyllata Thunb. The total polyphenol content was significantly higher in the methanol extract than in the water extract. The DPPH radical scavenging activity in the water extract was similar to Vit. C at a concentration of $100{\sim}200{\mu}g/mL$. The ABTS radical scavenging activity in the water and methanol extract was similar to Vit. C at a concentration of $800{\sim}1,000{\mu}g/mL$. The superoxide dismutase (SOD)-like activity in the methanol extract was similar to Vit. C at a concentration of $800{\sim}1,000{\mu}g/mL$. The DPPH, ABTS radical scavenging and (SOD)-like activity increased with increasing extract concentration. In a cell viability using MTT, the water extract (50 and 100 ppm) and methanol extract (100 ppm) had a protective effect against $H_2O_2$-induced neurotoxicity.The result ssuggest that the extract of E. caryophyllata Thunb. has antioxidant activities and may be useful for treating neurodegenerative disorders.

The Possible Protective Role of Korean Ginseng on Ochratoxicosis: with Special References on Chromosomal Aberrations in Rats.

  • Nada, Spomaia A.;Arbid, Mahmoud S.;Ramadan, A.I.
    • Proceedings of the Ginseng society Conference
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    • 1998.06a
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    • pp.253-262
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    • 1998
  • Ochratoxin A (OA) is a potent mycotoxin causing considerable health hazard and economic loss- e,i. OA is of concern as it is hepato-nephrotoxic, mutagenic, and carcinogenic to a great variety of animals. LDso of crude OA was 8.5 mgf kg.b.w., i.p. The clinical symptoms, mortalities and necropsy were recorded in rats injected with OA (LD5o, i.p.) during 10 days of daily treatment. Ginseng treatments (20 mg 1 kg. b.w., i.p.) : before, mixed with, or after OA dose, completely prevented the mortality in rats. OA-treated animals showed microcytic normochromic anaemia, lucocytosis, hypoproteinaemia and elevation of serum ALT, AST, AP, urea, and creatinine values. These findings were declined near the normal levels when ginseng injected with OA. OA (115 LDso) induced chromosomal aberrations (65.66%) compared to the control. When ginseng given 10 min before OA injection, chromosomal aberrations were reduced to be 31.66% compared to OA-treated animals. In conclusion: ginseng has a protective effect against ochratoxicosis, it has anti-genotoxic activity and it can repair the chromosomal damage induced by ochratoxin A. Key words Ochratoxicosis, Chromosomal aberrations, Mycotoxins, Ochratoxin A, Korean gin sting, Protective effect of Panax ginseng, Rat

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Protective Effect of Diallyl disulfide(DADS) from Garlic Extract on Noise Induced Hearing Loss in the Guinea pigs (소음으로 인한 청력소실에 대한 마늘 추출물 diallyl disulfide(DADS)의 효과)

  • Yoon, Min-Young;Cho, Nam-Geun;Hwang, Woo-Jun;Jang, Chul-Ho
    • Journal of Acupuncture Research
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    • v.19 no.2
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    • pp.105-113
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    • 2002
  • Objective : The purpose of this study is to investigate the protective effect of DADS on the noise induced hearing loss Methods : Twenty healthy guinea pigs (DADS pretreated group and control) were exposed to 100dB a collected environmental noise for 9 hours. An auditory evoked brainstem response (ABR) threshold was measured before and after a noise exposure. For morphological study, cochlea was studied by scanning electron microscope (SEM). Results : The DADS pretreated group showed statistically significant less changes in ABR threshold and SEM findings compared the control group. Conclusion : From these results suggest that the DADS from garlic may have a protective effect in noise induced hearing loss.

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An isolation of the active component of Carthamus tinctorius L. Semen and the evaluation of its hepato-protective effect

  • Jeong, Jeong-Suk;Jeong, Choon-Sik;Jung, Ki-Hwa
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1998.11a
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    • pp.179-179
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    • 1998
  • We previously reported the hepato-protective effect of butanol soluble fraction of methanolic extract of Carthamus tinctorius L. Semen on carbon tetrachloride induced hepatotoxicity. In this study, the active component from the butanol soluble fraction was isolated by column chromatographic separation using Silica gel and Sephadex LH -20 and identified by spectroscopic methods such as Mass, $^1$H - NMR and $\^$13/C-NMR. The hepato-protective effect of the isolated active component on the CCl$_4$-induced liver damaged rats has been evaluated by performing blood chemical analysis and biotransformational enzyme analysis.

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Enhanced Protective Effect of Ultrafine Particles of Red-Ginseng against Phenanthrene-induced Cell Damage

  • Seo, Yoo-Na;Lee, Mi-Young
    • Journal of Ginseng Research
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    • v.33 no.4
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    • pp.305-310
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    • 2009
  • Phenanthrene, one of the polycyclic aromatic hydrocarbons, has been known to be toxic to the environment. In this investigation, the protective effect of red ginseng on phenanthrene-induced oxidative DNA damage was evaluated using Comet assay in A549 cells. Red ginseng's cytoprotective effect on phenanthrene-induced hemolysis was also investigated. This study's findings show that oxidative DNA damage and hemolysis were significantly prevented by red ginseng treatment. Notably, it was found that pulverizing red ginseng into ultra-fine particles even enhanced its protective effects against DNA damage and hemolysis. The results suggest that particle size reduction seems to effectively enhance red ginseng's pharmacological efficacies.

Study on protective effect on hepatic damage by alcohol and CCl4 by Korea red ginseng-mixed formula (홍삼복합방(紅蔘複合方)의 보간작용(補肝作用)에 대(對)한 실험적(實驗的) 연구(硏究)(1))

  • Kang, Chang-Hee;Kim, Sung-hoon;Choi, Byong-gyun;Kim, Dong-hee
    • Journal of Haehwa Medicine
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    • v.9 no.1
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    • pp.135-142
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    • 2000
  • For the evaluation of protective effect on hepatic damage by Korean red ginseng mixed formula, we used GR(Korean red ginseng), GRF-A(Korean red ginseng-mixed formula) as a materials. The study was performed on protective effect against hepatic damage induced by $CCl_4$. In vitro assay with 1.1 mM galactosamine, protection(%) was 44%(GR), 58%(GRF-A) at 50ug/ml, while maxium protection(%) was 5%(GR) and 24% (GRF-A) against acute hepatotoxicity by $CCl_4$. GRF-A significantly protected ethanol induced-liver damage by lowering ALT and ALP and fatty degenertion in liver tissue.

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