• 제목/요약/키워드: Retardation of the aging

검색결과 16건 처리시간 0.017초

Retardation of Degradation in Accelerated Aging of Cotton Cellulose Using Borohydride Reduction

  • Kim, Hye-Kyung;Choi, Hyung-Min
    • International Journal of Human Ecology
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    • 제8권1호
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    • pp.1-8
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    • 2007
  • Degradation of cellulose during prolonged exposure in atmospheric conditions has been recognized as one of main problems in preserving cellulose-made products. The purpose of this research was therefore to study effects of borohydride reduction in improving both the color and strength retention of cotton fabrics artificially aged at temperatures ranging from $100^{\circ}C$ to $150^{\circ}C$. Results indicated that the fabrics treated with either sodium or tetramethylammonium borohydrides (TMA) were degraded at rates about one-half that of water-washed cotton. These results were consistent over the temperature range. Calculation of the activation energy (Ea) by different methods showed $Ea\;=\;25.5{\pm}\;1.5\;Kcal$, in keeping with measurements made by others at lower temperatures. The TMA-treatment was effective in minimizing discoloration of the fabrics with pre-baking, but not of the un-prebaked fabrics.

17-4 PH 스텐레스강의 수소취화방지에 관한 연구 (A study on the Reardation Embrittlement in 17-4 PH Stainaless steel)

  • 이헌봉;최상헌;김인배
    • 열처리공학회지
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    • 제6권3호
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    • pp.152-158
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    • 1993
  • Effects of oxide film which is grown by heat treatment on the hydrogen embrittlement (HE) of 17-4 PH stainless steel were investigated. Specimems were tensile tested after cathodic hydrogen charging and the be haviors of HE were evaluated from the elongation change. It was found that specimems solution treated at $1040^{\circ}C$ for 1/2hour showed best retardation ability to HE for both aging conditions i.e. $480^{\circ}C{\times}1hr$ and $620^{\circ}C{\times}4hrs$. X-ray and Auger study revealed that the major composition of oxide films are $Cr_2O_3$ and $CuCr_2O_4$.

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육미지황탕 효능의 동의보감과 실험연구결과의 비교고찰 -한의학과 중의학을 중심으로- (The Comparative Effects of Yugmijihwangtang in Donguibogam and Experiment Research Results -Focusing on the Korean Medicine and Traditional Chinese Medicine-)

  • 한유창;김명동;이선동
    • 대한한의학방제학회지
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    • 제25권2호
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    • pp.223-251
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    • 2017
  • Objectives : A lot of experiment results of Yugmijihwangtang(YM) are reported in various kinds of journals. Many of them report on the new effects that are not recorded in the traditional medical texts. So it is necessary to take it into consideration that newly reported effects could be of help to clinical practice, because this process of comparison of Donguibogam and scientific experiment results will have basis to lead into the evidence based medicine. Methods : We compared the effects of in Donguibogam and the experiment results of YM. Results : The effects of YM in Donguibogam are to replenish essence and marrow, and to treat red wen, fatigue, treat hypouresis, urinary sediment, urinary urgency, hematuria, hydrocephalus, speech and movement retardation, yin-deficiency, diabetes mellitus, nonalcoholic fatty liver, melanoma, disability to see near and far sight, tinnitus, hearing loss, alopecia, angiogenesis, cough, cough at night, trachyphonia, and, infantile convulsion. The experiment results of YM since 2000 in both Korea and China are to inhibit atopic dermatitis, renal interstitial fibrosis, anti-oxidant, emphysema, stress, glomerulosclerosis, diabetic nephropathy, chronic glomerulonephritis, hemorrhage, plantar sweating, dermal aging, kidney aging, bone loss, breast cancer, pathological myocardial cell, primary liver cancer, thrombosis, osteoporosis, intrauterine growth retardation, chronic renal failure, IgA nepropathy, slow cerebral development, and hippocampal tissue lesions on the one hand, and to help bone formation, renin-angiotensin- aldosterone system, cerebral recovery, cognitive function and expression, osteoblast proliferation and differentiation, learning and memory, cold-tolerance and oxygen deficit-tolerance and anti-fatigue, endometrial formation, humoral and cell-mediated immunity, immune regulation effect, Hypothalamus-Pituitary-Ovary Axis, and spermatogenesis, on the other hand. Conclusion : When we compared the effects of YM with the experiment results of YM, there existed a considerable gap between them. So, from now on, it is expected that a great effort and consideration are needed to solve these gaps from an academic and clinical point of view.

Hutchison-Gilford 조로증 증후군 환아에서의 뇌 자기공명 혈관조영술 소견: 증례 보고 (Detection of Cerebrovascular Disease in a Child with Hutchinson-Gilford Progeria Syndrome Using MR Angiography: A Case Report)

  • 이재호;이하영;임명관;강영혜
    • 대한영상의학회지
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    • 제83권6호
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    • pp.1360-1365
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    • 2022
  • Hutchinson-Gilford progeria 증후군(syndrome) (이하 HGPS)은 심혈관 및 뇌혈관 질환의 조기 이환율을 갖는 드문 진행성 조기 노화 증후군이다. 임상증상은 매우 다양하여 성장 부진, 경피증, 탈모증, 골다공증과 같은 비특이적 증상 외에도 가속화된 혈관 노화에 의해 유년기 및 청소년기에 발생하는 고혈압과 심뇌혈관 질환을 포함한다. HGPS 환자에게 자기공명 혈관조영술은 무증상 뇌졸중 또는 혈관 변화를 조기에 진단하고 뇌혈관 질환의 위험성 증가를 평가하기 위해 권장된다. 이 증례 보고는 전형적인 임상 특징을 보인 5세 환아에서 유전자분석으로 확진된 국내 두 번째 HGPS이며, 뇌 자기공명 혈관조영술 소견을 제시한 국내 최초 영문 증례 보고이다.

DNA damage to human genetic disorders with neurodevelopmental defects

  • Lee, Youngsoo;Choi, Inseo;Kim, Jusik;Kim, Keeeun
    • Journal of Genetic Medicine
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    • 제13권1호
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    • pp.1-13
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    • 2016
  • Although some mutations are beneficial and are the driving force behind evolution, it is important to maintain DNA integrity and stability because it contains genetic information. However, in the oxygen-rich environment we live in, the DNA molecule is under constant threat from endogenous or exogenous insults. DNA damage could trigger the DNA damage response (DDR), which involves DNA repair, the regulation of cell cycle checkpoints, and the induction of programmed cell death or senescence. Dysregulation of these physiological responses to DNA damage causes developmental defects, neurological defects, premature aging, infertility, immune system defects, and tumors in humans. Some human syndromes are characterized by unique neurological phenotypes including microcephaly, mental retardation, ataxia, neurodegeneration, and neuropathy, suggesting a direct link between genomic instability resulting from defective DDR and neuropathology. In this review, rare human genetic disorders related to abnormal DDR and damage repair with neural defects will be discussed.

후기 노인의 활동을 제한하는 주요 신체적 건강 상태와 장애 분석 (Analysis of Major Physical Health Conditions and Disabilities that Limit Activity in Later Stage Elderly)

  • 이효택;노효련
    • 대한물리의학회지
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    • 제19권2호
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    • pp.99-106
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    • 2024
  • PURPOSE: This study is a data analysis study to determine the physical health problems and reasons for disabilities and activity limitation rates that limit daily life and social activities among the elderly population aged 75 or older in Korea. METHODS: This study data was extracted from the raw data of the 7th National Health and Welfare Survey (2016-2018). The subjects of this study were 1,995 elderly people (823 men, 1,172 women) aged 75 years or older. The collected data were analyzed using frequency analysis and logistic regression analysis. RESULTS: From 2016 to 2018, the activity limitation rate among the elderly population aged 75 or older in Korea was 20.6% for men, 24.6% for women, and 23.1% overall. The three major diseases with the highest frequency of activity limitations were back and neck problems (36.5%), arthritis and rheumatism (28.7%), and knee and leg pain (14.7%). Activity limitation due to old age was found to be 13.1%, making it the fourth most frequent reason. The rate of activity limitations due to mental retardation and obesity was found to be 0%. The three major activity limitation rates were significantly related to gender. CONCLUSION: The main diseases causing activity limitations among the elderly population aged 75 or older in Korea were back and neck problems, arthritis and rheumatism, and musculoskeletal diseases such as knee and leg pain. Therefore, it is believed that it can be used as basis data for reducing the activity limitation rate of the elderly population in the aging era.