• 제목/요약/키워드: stress resistance

검색결과 2,288건 처리시간 0.027초

Resistance of SOD2-transgenic petunia line to oxidative stress

  • Lee, Su-Young;Han, Bong-Hee;Kim, Yeong-Tae;Kim, Jin-Seog
    • Journal of Plant Biotechnology
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    • 제37권4호
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    • pp.562-566
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    • 2010
  • SOD2-transgenic $T_3$ petunia line (A2-36-2-1-1-35) was treated with different levels of methyl viologen (MV) to determine its resistance to oxidative stress. Four (4) levels of MV (0, 100, 200, and $400\;{\mu}M$) were applied. The SOD2-transgenic $T_3$ petunia line exhibited a very significant oxidative stress resistance at the highest MV concentration ($400\;{\mu}M$) treatment compared to non-transgenic plant. RNA and protein expression of SOD2 transgene and higher parenchyma cell density in the transgenic petunias exhibiting resistance to oxidative stress proves its contribution to the expression of its resistance to oxidative stress.

응력이력이 사질토의 CPT-DMT 상관관계에 미치는 영향 (Effect of Stress History on CPT-DMT Correlations in Granular Soil)

  • 이문주;최성근;김민태;이주형;이우진
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 춘계 학술발표회
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    • pp.730-739
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    • 2010
  • Stress history increases in penetration resistance due to the increase in residual horizontal stress of granular soil. This study analyzes the effect of stress history on the results of CPT and DMT from calibration chamber specimen in OC as well as NC state. Test results show that the normalized cone resistance by mean effective stress correlates well with the relative density and the state parameter, whereas the normalized cone resistance with regard to vertical effective stress is a little affected by stress history. The horizontal stress index($K_D$) in DMT more reflects the influence of stress history on granular soil than the dilatometer modulus($E_D$) and cone resistance($q_c$). The $K_D/K_0$, in which the effect of stress history on $K_D$ is compensated by the at-rest coefficient of earth pressure, $K_0$, is related to relative density, state parameter and the normalized cone resistance by mean effective stress. It is also observed that the normalized dilatometer modulus by mean effective stress($E_D/{\sigma_m}'$) is unique correlated with the state parameter, regardless of stress history.

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Can antioxidants be effective therapeutics for type 2 diabetes?

  • Park, Soyoung;Park, So-Young
    • Journal of Yeungnam Medical Science
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    • 제38권2호
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    • pp.83-94
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    • 2021
  • The global obesity epidemic and the growing elderly population largely contribute to the increasing incidence of type 2 diabetes. Insulin resistance acts as a critical link between the present obesity pandemic and type 2 diabetes. Naturally occurring reactive oxygen species (ROS) regulate intracellular signaling and are kept in balance by the antioxidant system. However, the imbalance between ROS production and antioxidant capacity causes ROS accumulation and induces oxidative stress. Oxidative stress interrupts insulin-mediated intracellular signaling pathways, as supported by studies involving genetic modification of antioxidant enzymes in experimental rodents. In addition, a close association between oxidative stress and insulin resistance has been reported in numerous human studies. However, the controversial results with the use of antioxidants in type 2 diabetes raise the question of whether oxidative stress plays a critical role in insulin resistance. In this review article, we discuss the relevance of oxidative stress to insulin resistance based on genetically modified animal models and human trials.

변화수용성과 번영 간 관계에서 변화저항과 직무스트레스의 이중 매개효과 (A Double Mediating Effect of Resistance and Job Stress between Acceptance and Flourishing in Organizational Change)

  • 이현주;정승철
    • 벤처혁신연구
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    • 제4권3호
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    • pp.89-108
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    • 2021
  • 본 연구는 조직의 변화과정 이후 개인의 변화에 대한 인식과 태도가 변화수용성, 직무스트레스, 번영에 미치는 이중 매개효과를 검증하고자 하였다. 이를 위해 직장인 300명을 대상으로 설문을 실시하였으며, 변화수용성은 번영감에 정(+)의 영향을, 조직변화저항과 직무스트레스에 부(-)의 영향을, 조직변화저항은 직무스트레스에 정(+)의 영향을, 번영에 부(-)의 영향을, 직무스트레스는 번영에 부(-)의 영향을 미치는 것을 확인하였다. 또한, 변화수용성과 번영 간에 조직변화저항과 직무스트레스의 매개효과를, 변화수용성과 번영 간 및 변화수용성과 직무스트레스 간에 조직변화저항의 완전매개효과를, 조직변화저항과 번영 간 및 변화수용성과 번영 간에 직무스트레스의 부분매개 효과를 확인하였다. 마지막으로 변화수용성과 번영 간 조직변화저항과 직무스트레스는 이중 매개효과가 나타났다. 본 연구의 시사점과 제한점, 후속연구 방향성을 제시하였다.

저항운동 프로그램이 제 2형 당뇨병 노인의 자가간호, 스트레스 및 당화혈색소에 미치는 효과 (The Effects of Resistance Exercise Program for Elders with Type 2 Diabetes on the Self Care, Stress and HbA1c)

  • 이선우;신성례
    • 성인간호학회지
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    • 제20권3호
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    • pp.431-442
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    • 2008
  • Purpose: The purpose of this study was to examine the effects of resistance exercise program for elders with type 2 Diabetes on the self care, stress and HbA1c. Methods: Thirty three elders with type 2 Diabetes(18 experimental and 15 control subjects) were selected conveniently among the aged who had been enrolled in a community senior center. The subjects in experimental group participated in a resistance exercise program for 8 weeks. Data were analyzed using the SPSS/Win 12.0. Results: The resistance exercise program showed a statistical difference in self care(t=-4.39, p=.000) and stress(t=2.22, p=.034). However, there was not a statistical difference in HbA1c (F=.556, p=.557), but experimental group had decreased continuously in HbA1c after the program. Conclusion: The resistance exercise program improved self care and reduced the stress in the elders with type 2 Diabetes. Therefore, resistance exercise program can be applied as an effective nursing intervention to promote self care, decrease the stress and to prevent complication for the elders with type 2 Diabetes.

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반복단순전단 시험에 의한 패각질 모래의 동적 거동 (Dynamic Behaviors of Shelly Sand in Cyclic Simple Shear Test)

  • 윤여원;윤길림;최재권;김재권;김승현
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2006년도 춘계 학술발표회 논문집
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    • pp.1358-1366
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    • 2006
  • In order to study the effects of shell contents on the liquefaction resistance of the shelly sand, NGI cyclic simple shear tests were performed for the shelly sands with shell contents of 0%, 5%, 10%, 20% and 30% under the effective vertical stress of 50kPa, 100kPa and 150kPa for 40% and 55% of relative density, respectively. Cyclic simple shear test results showed that for the low effective vertical stress, liquefaction resistance increased rapidly with the increase of shell contents in both 40% and 55% relative density. On the other hand, for the high effective vertical stress, the liquefaction resistance increased slightly in 40% relative density whereas the resistance was almost same in 55% relative density. Liquefaction resistance decreased with increasing effective vertical stress for both 40% and 55% relative density. In the same effective vertical stress and shell contents, liquefaction resistance increased with the increase of relative density of sands.

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Arctigenin Inhibits Etoposide Resistance in HT-29 Colon Cancer Cells during Microenvironmental Stress

  • Yoon, Sae-Bom;Park, Hae-Ryong
    • Journal of Microbiology and Biotechnology
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    • 제29권4호
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    • pp.571-576
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    • 2019
  • Microenvironmental stress, which is naturally observed in solid tumors, has been implicated in anticancer drug resistance. This tumor-specific stress causes the degradation of topoisomerase $II{\alpha}$, rendering cells resistant to topoisomerase $II{\alpha}$-targeted anticancer agents. In addition, microenvironmental stress can induce the overexpression of 78kDa glucose regulated protein (GRP78), which can subsequently block the activation of apoptosis induced by treatment with anticancer agents. Therefore, inhibition of topoisomerase $II{\alpha}$ degradation and reduction in GRP78 expression may be effective strategies for inhibiting anticancer drug resistance. In this study, we investigated the active compound arctigenin, which inhibited microenvironmental stress-induced etoposide resistance in HT-29 cells. Arctigenin was also highly toxic to etoposide-resistant HT-29 cells, with an $IC_{50}$ value of $10{\mu}M$ for colony formation. We further showed that arctigenin inhibited the degradation of topoisomerase $II{\alpha}$ and reduced the expression of GRP78. Thus, these results suggest that arctigenin is a novel therapeutic agent that inhibits resistance to etoposide associated with microenvironmental stress conditions.

사질토 지반에서의 정적관입저항과 기준응력과의 관계 (The Relationship Between Static Cone Penetration Resistance and the Reference Stress in Sandy Soils)

  • 백세환;이명환;이원제
    • 한국지반공학회지:지반
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    • 제6권4호
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    • pp.33-42
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    • 1990
  • 정적관입저항 또는 선단지지말뚝의 선단지지력을 해석함에 있어서는 유효수직응력이 기준음력으로 사용되어 왔다. 그러나 정적관입저항은 유효수직응력보다 원위치 유효수평응력에 관계된다는 것이 많은 실험연구결과로부터 보고 되었다. 이와같은 문제점을 규명하기 위하여 기 보고된 실험결과를 다시 분석하였으며 실험실에서의 관입시험이 실시되었다. 연구결과 정적관입저항은 유효수직 응력과 유효수평응력 모두에 영향을 받는 것으로 나타나고 있으며 해석시에는 평균주응력이 기준응력으로 사용되어야 함을 결론 지을 수 있었다.

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일개 사업장 근로자들의 한방건강검진에서 심박동변이도(HRV) 측정을 통한 음주와 흡연여부에 따른 스트레스 결과 분석 (A Study of the Relationship between Drinking, Smoking and Stress of Workers by Analyzing Heart Rate Variability)

  • 박영선;김석중;김종대
    • 대한한의학회지
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    • 제29권1호
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    • pp.134-145
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    • 2008
  • Objectives : This study investigated the relationship between drinking, smoking and stress of workers by analyzing heart rate variability. The subjects were workers in the automobile manufacturing industry. Methods : The subjects consisted of 21,239 and 19,999 industrial workers who had received health examination by Korean oriental medicine and submitted questionnaires about drinking history and smoking history, during 8 months from April to November. The subjects were categorized into drinking history and smoking history. The heart rate variability was measured for five minute at rest using SA-3000P (Medicore) and reported stress severity as stress index, stress resistance and fatigue. We analyzed the relationship between drinking, smoking and stress into frequencies, $x^2$-test using the SPSS Ver. 12.0. Results : Regarding the relationship between drinking and stress index orstress resistance, there was no statistically significant difference, but regarding the relationship between drinking and fatigue, the drinker group had a significantly higher level of fatigue than the non-drinker group. There was a statistically significant difference in stress index, stress resistance and fatigue between the current-smoker group and others. Stress resistance of the current-smoker group had lower levels than the non-smoker group or ex-smokers. On the other hand, stress index and fatigue of the current-smoker group had higher levels than the non-smoker group or ex-smokers. Conclusions : The above results revealed that drinking and smoking could put workers under a lot of stress. Smoking workers were especially apt to be under stress and had difficulty in alleviating stress.

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한방건강검진을 통해 살펴본 운동과 건강관련 요인과의 관계 (A Relationship between Exercise and Health Factors including Stress, Fatigue and Vaso-aging degree)

  • 정현정;김승모
    • 대한한의진단학회지
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    • 제17권2호
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    • pp.122-130
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    • 2013
  • Objectives This study investigated the relationship between exercise and health factors including vaso-aging degree, stress index, stress resistance, fatigue and activity of autonomic nerve system etc. Methods The subjects were 20,509 persons who had received health examination by Korean Medicine and submitted questionnaires about exercise history, for 8 months from March to November in 2011. The vaso-aging degree were measured by APG (Accelerated Photoplethysmograph). The stress index and resistance, fatigue and activity of autonomic nerve system were measured by HRV (Heart Rate Variability). We analyzed the relationship between exercise and various variables by chi-square test with SPSS ver. 19.0. Results Regarding the relationship between exercise and vaso-aging degree, stress index, stress resistance, fatigue and activity of autonomic nerve system, there were significant differences(p<0.05). Conculsions This study suggests that vaso-aging degree, stress index, stress resistance, fatigue and activity of autonomic nerve system are affected by exercise.