• 제목/요약/키워드: blocked practice

검색결과 33건 처리시간 0.018초

영양소의 변천과 식물육종의 추이 (Changes in the Concept of Nutrients and Transition of Plant Breeding)

  • 한창열
    • Journal of Plant Biotechnology
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    • 제30권4호
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    • pp.387-397
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    • 2003
  • During the first half of twentieth century, even though the importance of non-calorie essential micronutrients of 13 vitamins and 17 minerals has been known to alleviate nutritional disorder; the primary objective of agriculture and plant breeding programs has been to increase the productivity and seed yields, and macronutrients of proteins, fats, and carbohydrates made up the bulk of foodstuff which were used primarily as an energy source. In the last decade it has been found that non-essential micronutrients encompass a vast group of phytochemicals including antioxidants that are not strictly required in the diet but when present at sufficient levels work as health-promoting chemicals. Nowadays agricultural crops are grown for health rather than for food or fiber, and modifying the nutritional compositions of plant foods has become an urgent health issue. To ensure an adequate intake of essential vitamins and minerals, and to increase the consumption of health-promoting phytochemicals, the researches on plant secondary metabolism have been made. The attempt to improve nutritional quality of crops has been blocked by a lack of basic knowledge of plant metabolism. The advent of genomics era enabled new approaches to make crossing regardless of species, family, or phylum barriers, and the accumulation in our basic knowledge on plant secondary metabolism during the coming decade would be tremendous. As the major staple crops contain insufficient amount of many micronutrients, fortification strategy will be a necessary practice. Elevated intake of specific vitamins, C, E, and $\beta$-carotene, mineral selenium, antioxidants, and phytochemicals significantly reduces the risk of chronic disease such as cancer, cardiovascular disorder, diabetis, and other degenerative disease associated with aging. As the attempt to improve the nutritional quality of crops requires the basic knowledges on plant metabolism, plant biochemistry, human physiology, and food chemistry, strong interdisplinary collaboration among plant biotechnologists, human nutritionists, and food scientists will be needed. Inhibition of cancer, cardiovascular disease, and other degenerative disorder may be the biggest goal facing nutritional plant breeders. But the assumption that simply increasing dietary level of any compound will necessarily improve human health is a dangerous idea because many plant secondary products and dietary contaminants have paradoxical (hermetic) effects. Before biotechnical manipulation is undertaken to elevate or reduce any individual constituent of crops, the contribution of the micronutrient to human health must first be investigated.

상아질 지각완화제가 치과용 시멘트의 결합강도에 미치는 영향 (THE INFLUENCE OF DENTIN DESENSITIZER TO SHEAR BOND STRENGTH OF DENIAL CEMENTS)

  • 나윤호;오남식;유재흥
    • 대한치과보철학회지
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    • 제45권5호
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    • pp.579-588
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    • 2007
  • Statement of problem: A tenderness of the dentin after tapering of teeth for dental prosthesis is a common phenomenon. In practice, the alternative desensitizer may be used for minor pain after tapering of teeth. Purpose: In this study, the desensitizers were used to investigate the affect decreasing of shear bond strength according to the use of various cement, such as resin, Glass Ionomer, and phosphate cement. Material and method: Three different desensitizers were used on this study Compositions of two dentin desensitizers were HEMA(hydroxyethylmethacrylate) and glutaraldehyde. The other one is oxalic acid. Three dentin desensitizers applied on 12 degrees taper teeth. Then, Ni-Cr crowns were bonded with Resin cement, Zinc Phosphate (ZPC) cement and Glass Ionomer (GIC) cement. 120 human premolar teeth were used for specimens. The specimens were divided into four group as the reference and the empirical each with thirty specimens, then further divided into 12 group according to type of desensitizers and cement types. The shear bond strength were measured by Instron multi task instrument. Results: According to the result, the measured shear bond strength in order from the weakest to the strongest in general was ZPC, Resin, and GIC. And it is found that the application of desensitizers on dentin surface does not affect the shear bond strength. Conclusion: Dentin desensitizers that alleviate or prevent a dentin tenderness, usually contains HEMA and glutaraldehyde compounds. Such desensitizers are widely used in clinical studies. By applying the dentin desensitizer on the exposed dentin surface, the dentin capillary are blocked and periodontal membrane and cementum can not be drawn in pulp cavity. Since HEMA and glutaraldehyde may cause harm to the pulp cavity, an alternative desensitizer was developed.

관상동맥혈관용 스텐트의 구조해석과 재료설계 (Material Design and Analysis of Coronary Artery Stents)

  • 박중권;강태원;이기성;김태우
    • 한국세라믹학회지
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    • 제44권7호
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    • pp.362-367
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    • 2007
  • Stent is a tiny structure made with either ceramic coating and/or bare metal. Being approximately $1{\sim}2 mm$ in diameter, it consists of holes, slots, or void space and is designed to cover entire medical lesions. Stent implantation into patients' arteries has been practiced for a little more than a decade in order to widen the blocked artery. The adoption of the stent has significantly improved the efficacy when compared with the previous medical practice by balloon angioplasty alone. Yet better biomedical performance of the stent is being demanded in order to eliminate the still existing problem of artery restenosis, which means the artery becomes narrowed again. Recent literature survey shows researches on ceramic coatings onto the stent surface, or material design to improve the mechanical response of the stent. This study focuses more on the material design and mechanical analysis. The results showed that the void configuration within the stent affects the mechanical response significantly. The rectangular shape was found to yield expansion at a relatively lower pressure than the elliptical slot for a slotted tube stent. The present results, when combined with research on coating at the stent surface, may provide stents with improved bio-medical performance.

Ethanol extract of Allium fistulosum inhibits development of non-alcoholic fatty liver disease

  • Hwang, Jin-Taek;Shin, Eun Ju;Chung, Min-Yu;Park, Jae Ho;Chung, Sangwon;Choi, Hyo-Kyoung
    • Nutrition Research and Practice
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    • 제12권2호
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    • pp.110-117
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    • 2018
  • BACKGROUND/OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is a leading cause of chronic liver disease and is closely associated with metabolic syndrome. In the present study, we observed the effect of ethanol extract of Allium fistulosum (EAF) on NAFLD and have suggested the possibility of using EAF as a natural product for application in the development of a treatment for NAFLD. MATERIALS/METHODS: The preventive effect on hepatic lipid accumulation was estimated by using an oleic acid (OA)-induced NAFLD model in vitro and a Western diet (high-fat high-sucrose; WD)-induced obese mouse model. Animals were divided into three groups (n = 7): normal diet group (ND), WD group, and WD plus 1% EAF group. RESULTS: EAF reduced OA-stimulated lipid accumulation in HepG2 cells in the absence of cellular cytotoxicity and significantly blocked transcriptional activation of sterol regulatory element-binding protein 1 and fatty acid synthase genes. Subsequently, we investigated these effects in vivo in mice fed either ND or WD in the presence or absence of EAF supplementation. In comparison to the ND controls, the WD-fed mice exhibited increases in body weight, liver weight, epididymal fat weight, and accumulation of fat in hepatocytes, and these effects were significantly attenuated by EAF supplementation. CONCLUSIONS: Allium fistulosum attenuates the development of NAFLD, and EAF elicits anti-lipogenic activity in liver. Therefore, EAF represents a promising candidate for use in the development of novel therapeutic drugs or drug combinations for the prevention and treatment of NAFLD.

Beneficial effects of natural Jeju groundwaters on lipid metabolism in high-fat diet-induced hyperlipidemic rats

  • Wang, Yan-Chao;Lu, Jin-Miao;Jin, Hui-Zi;Ma, Ai-Niu;Zhang, Jin-Yang;Gong, Nian;Xiao, Qi;Zhu, Bin;Lv, Ying-Fang;Yu, Na;Zhang, Wei-Dong;Wang, Yong-Xiang
    • Nutrition Research and Practice
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    • 제8권2호
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    • pp.165-171
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    • 2014
  • BACKGROUND: Groundwater is believed to possess many beneficial effects due to its natural source of various minerals. In this study, we examined the effects of natural Jeju groundwater S1 (Samdasoo$^{TM}$), S2 and S3 pumped up from different locations of Jeju Island, Korea, along with local tap water, on body weight gain, serum lipids and lipoproteins, and liver histopathology in high-fat diet-induced hyperlipidemic rats. MATERIALS/METHODS: Rats were randomly and equally divided into 6 groups. Different water samples were supplied to the hyperlipidemic rats as their daily drinking water and the widely-used anti-hyperlipidemic drug simvastatin was used as a positive control. Body weight, serum lipids and lipoproteins were measured weekly. Liver weight, liver index and liver histopathology were examined after the execution of the rats. RESULTS: After drinking Jeju groundwaters for two months, S2 but not S3 significantly reduced weight growth and serum triglycerides levels and increased high density lipoprotein-C (HDL-C) without affecting total cholesterol or LDL-C. S1 and particularly S2 significantly reduced the severity of liver hypertrophy and steatosis. All Groundwaters had much higher contents of vanadium (S3>S2>S1>>tap water) whereas S1 and S2 but not S3 markedly blocked autoxidation of ferrous ions. CONCLUSION: Jeju Groundwater S1 and particularly S2 exhibit protective effects against hyperlipidemia and fatty liver and hypothesize that the beneficial effect of Jeju Groundwaters may be contributed from blockade of autoxidation of ferrous ions rather than their high contents of vanadium.

Nutrition Practice to Alleviate the Adverse Effects of Stress on Laying Performance, Metabolic Profile, and Egg Quality in Peak Producing Hens: I. The Humate Supplementation

  • Hayirli, Armagan;Esenbuga, N.;Macit, M.;Lacin, E.;Karaoglu, M.;Karaca, H.;Yildiz, L.
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권9호
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    • pp.1310-1319
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    • 2005
  • This experiment was conducted to determine the effects of cage density (CD) and humate supplementation (HS) on laying performance, metabolic profile, and egg quality during the peak production period in hens. Lohman layers (n = 180, 46 wks of age) were blocked according to the location of cages and then allocated randomly to two levels of CD (4 or 6 hens per cage or 540 vs. 360 $cm^2$/hen) and three levels of HS (0, 0.15, and 0.30%). Egg production (EP) and feed consumption (FC) were measured daily; egg weight was measured bi-weekly; and BW was measured before and after the experiment. Blood and additional egg samples were obtained at the end of the experiment for determination of metabolic profile and egg quality. The data were analyzed using two-way ANOVA as repeated measures. Except for FC, CD did not affect laying performance parameters. Hens placed in high-density cages had lower FC than hens placed in normal-density cages. Increasing HS level linearly increased FC, EP, and feed conversion ratio (FCR). There was a CD by HS interaction effect on FC and EP. Hens placed in high-density cages had greater serum glucose, total protein, albumin, globulin, Ca, and P concentrations and tended to have greater serum corticosterone concentration than hens placed in normaldensity cages. Increasing HS level linearly increased serum glucose, total protein, albumin, globulin, creatine, and Ca concentrations and linearly decreased serum triglyceride and very low-density lipoprotein concentrations. There was a CD by HS interaction effect on serum glucose and albumin concentrations. There were no alterations in egg quality parameters in response to increasing CD. Albumen index and Haugh unit decreased linearly and other egg quality parameters did not change as HS level increased. In conclusion, increased caging density adversely affected metabolic profile, despite insignificantly deteriorating laying performance. Moreover, benefits from humate supplementation seem to be more noteworthy for hens housed in stressing conditions than for hens housed in standard conditions.

Corni Fructus attenuates testosterone-induced benign prostatic hyperplasia by suppressing 5α-reductase and androgen receptor expression in rats

  • Hwangbo, Hyun;Kwon, Da He;Choi, Eun Ok;Kim, Min Yeong;Ahn, Kyu Im;Ji, Seon Yeong;Kim, Jong Sik;Kim, Kyung-Il;Park, No-Jin;Kim, Bum Hoi;Kim, Gi-Young;Hong, Su-Hyun;Park, Cheol;Jeong, Ji-Suk;Choi, Yung Hyun
    • Nutrition Research and Practice
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    • 제12권5호
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    • pp.378-386
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    • 2018
  • BACKGROUND/OBJECTIVES: Benign prostatic hypertrophy (BPH) is a major cause of abnormal overgrowth of the prostate mainly in the elderly. Corni Fructus has been reported to be effective in the prevention and treatment of various diseases because of its strong antioxidant effect, but its efficacy against BPH is not yet known. This study was designed to evaluate the therapeutic efficacy of Corni Fructus water extract (CF) in testosterone-induced BPH rats. MATERIALS/METHODS: To induce BPH, rats were intraperitoneal injected with testosterone propionate (TP). Rats in the treatment group were orally administered with CF with TP injection, and finasteride, which is a selective inhibitor of $5{\alpha}$-reductase type 2, was used as a positive control. RESULTS: Our results showed that the increased prostate weight and histopathological changes in BPH model rats were suppressed by CF treatment. CF, similar to the finasteride-treated group, decreased the levels of testosterone and dihydrotestosterone by TP treatment in the serum, and it also reduced $5{\alpha}$-reductase expression and concentration in prostate tissue and serum, respectively. In addition, CF significantly blocked the expression of the androgen receptor (AR), AR co-activators, and proliferating cell nuclear antigen in BPH rats, and this blocking was associated with a decrease in prostate-specific antigen levels in serum and prostate tissue. CONCLUSIONS: These results suggest that CF may weaken the BPH status through the inactivation of at least $5{\alpha}$-reductase and AR activity and may be useful for the clinical treatment of BPH.

Effects of lycopene on number and function of human peripheral blood endothelial progenitor cells cultivated with high glucose

  • Zeng, Yao-Chi;Mu, Gui-Ping;Huang, Shu-Fen;Zeng, Xue-Hui;Cheng, Hong;Li, Zhong-Xin
    • Nutrition Research and Practice
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    • 제8권4호
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    • pp.368-376
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    • 2014
  • BACKGROUND/OBJECTIVES: The objectives of this study were to investigate the effects of lycopene on the migration, adhesion, tube formation capacity, and p38 mitogen-activated protein kinase (p38 MAPK) activity of endothelial progenitor cells (EPCs) cultivated with high glucose (HG) and as well as explore the mechanism behind the protective effects of lycopene on peripheral blood EPCs. MATERIALS/METHODS: Mononuclear cells were isolated from human peripheral blood by Ficoll density gradient centrifugation. EPCs were identified after induction of cellular differentiation. Third generation EPCs were incubated with HG (33 mmol/L) or 10, 30, and $50{\mu}g/mL$ of lycopene plus HG. MTT assay and flow cytometry were performed to assess proliferation and apoptosis of EPCs. EPC migration was assessed by MTT assay with a modified boyden chamber. Adhesion assay was performed by replating EPCs on fibronectin-coated dishes, after which adherent cells were counted. In vitro vasculogenesis activity was assayed by Madrigal network formation assay. Western blotting was performed to analyze protein expression of both phosphorylated and non-phosphorylated p38 MAPK. RESULTS: The proliferation, migration, adhesion, and in vitro vasculogenesis capacity of EPCs treated with 10, 30, and $50{\mu}g/mL$ of lycopene plus HG were all significantly higher comapred to the HG group (P < 0.05). Rates of apoptosis were also significantly lower than that of the HG group. Moreover, lycopene blocked phosphorylation of p38 MAPK in EPCs (P < 0.05). To confirm the causal relationship between MAPK inhibition and the protective effects of lycopene against HG-induced cellular injury, we treated cells with SB203580, a phosphorylation inhibitor. The inhibitor significantly inhibited HG-induced EPC injury. CONCLUSIONS: Lycopene promotes proliferation, migration, adhesion, and in vitro vasculogenesis capacity as well as reduces apoptosis of EPCs. Further, the underlying molecular mechanism of the protective effects of lycopene against HG-induced EPC injury may involve the p38 MAPK signal transduction pathway. Specifically, lycopene was shown to inhibit HG-induced EPC injury by inhibiting p38 MAPKs.

뇌졸중 환자가 지각하는 사회적 지지와 희망과의 관계 (The Correlation between Perceived Social Support and Hope of Stroke Survivors)

  • 김경옥;조복희
    • 재활간호학회지
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    • 제4권1호
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    • pp.58-72
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    • 2001
  • A Cerebrovascular accident(CVA), or Stroke is a medical emergency that occurred when the blood supply to the brain is interrupted or blocked. The stroke causes physical function disorder due to hemiparalysis and emotional disorder. Also the stroke patients experience helplessness, powerlessness, sense of alienation and loss of hope. These feelings make the rehabilitation difficult because they lose the will of life. The purpose of this study is to identify the correlation between perceived social support and hope of stroke survivors. The subjects for this study were 100 out-patients with stroke in one general hospital and oriental medicine hospital located in Mokpo. The data were analysed by frequency, t-test, ANOVA. Duncan test, Pearson's correlation, using the SPSS WIN 9.0 program. Data were collected from July 11 to September 9, 2000, using a structured questionnaire. The instruments used for this study : The social support scale developed by Park, Ji-won(1985) and the hope scale developed by Miller(1988). The results were as follows. 1. It was found that the higher the degree of perceived social support, the higher the degree of hope(r=.726, p=.000). Therefore hypothesis was supported. 2. The mean score of perceived social support was 77.8(SD=21.0) with a score range from 27.0 to 104.0. 3. The mean score of perceived hope was 117.0(SD=25.7) with a score range from 57.0 to 160.0. 4. The level of social support depending on general characteristics were significantly different in variables such as marital status(t=3.131, p=.010). degree of income satisfaction(F=16.027, p=.000). 5. The level of hope depending on general characteristics were significantly different in variables such as marital status(t=2.681, p=.040). current job(t=-2.055, p=.043) degree of income, satisfaction(F=11.363, p=.000). For these subjects, there was a significant relationship between social support and hope. The stroke survivors need social support to inspire their hope. Nurses should plan interventions to enhance social support for patients with stroke. The above results may be used as the basic data to seek more efficient way of elevating nursing practice and rehabilitation for the patients with stroke.

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치료 방사선 선속(Flux)에 포함된 산란전자의 분포와 에너지 측정 (The Measurements of Energy and Distribution of Scattered Electrons in Therapeutic X-Ray Beam)

  • Vahc, Young-Woo;Park, Kyung-Ran;Ohyun Kwon;Lee, Yong-Ha;Kim, Tae-Hong;Kim, Sookil
    • 한국의학물리학회지:의학물리
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    • 제13권1호
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    • pp.1-8
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    • 2002
  • 치료방사선 선형가속기에서 출력되는 광자선의 선속 (flux)에는 gantry head로부터 발생되는 오염전자를 포함하고 있으며, 오염전자의 발생은 주로 gantry head의 부속장비 또는 방사선 치료를 위해 gantry head 밑에 설치되는 부속장치 등에서 광자선과 매질의 전자쌍생성, 또는 컴프톤 산란전자 등의 물리적 현상으로 발생된다. 오염전자는 표면영역의 수cm 깊이의 선량 분포에 영향을 주고 있으며, 이것은 방사선 치료 시 skin-sparing 효과를 감소시키는 등 임상적인 측면에 영향을 주고 있다. 그러므로 선형가속기에서 발생되는 오염전자의 특성을 이해 할 필요가 있다. 본 연구는 선형가속기 (Clinac 1800, Varian )에서 출력되는 15MV 광자 선속에서 조사야의 크기가 0.0$\times$10.0 to 30.0$\times$30.0 $\textrm{cm}^2$에서 30.0$\times$30.0 $\textrm{cm}^2$ 대해 구리판(Cu)의 부분적 오염전자 제거 능력과, 조사야의 부분 차폐 방법을 이용하여 물팬톰 내의 선량분포의 변화를 측정하므로써 오염전자의 특성을 분석하였다. 그 결과 오염전자는 조사야의 중심축으로부터 넓게 퍼진 cone 모양의 분포를 하고 있었으며, 또한 오염전자가 갖는 평균 에너지는 약 3.0MeV로 나타났다. 그러므로 오염전자는 표면으로부터 2.5cm 깊이까지 분포하였다. 이러한 결과로써 광자선속에 포함된 오염전자를 제거하고 순수한 광자선을 이용한다면 buildup 영역 및 표면선량이 감소되고, 최대선량지점이 좀더 깊어진다.

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