• The Korean Journal of Physiology and Pharmacology
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• 제7권1호
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• pp.1-3
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• 2003

To investigate the receptors mediating the regulation of norepinephrine (NE) release in human cerebral cortex slices, we examined the effects of opioid agonists for ${\mu}$-, ${\delta}$-, and ${\kappa}$-receptors on the high potassium (15 mM)-evoked release of [$^3H$]NE. [$^3H$]NE release induced by high potassium was calcium-dependent and tetrodotoxin-sensitive. [$D-Pen^2$, $D-Pen^5$]enkephalin (DPDPE) and deltorphin II (Delt II) inhibited the stimulated release of norepinephrine in a dose-dependent manner. However, Tyr-D-Ala-Gly-(Me)Phe-Gly-ol and U69,593 did not influence the NE release. Inhibitory effect of DPDPE and Delt-II was antagonized by naloxone, naltrindole, 7-benzylidenaltrexone and naltriben. These results suggest that both ${\delta}_1$ and ${\delta}_2$ receptors are involved in regulation of NE release in human cerebral cortex.

• Preventive Nutrition and Food Science
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• 제7권1호
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• pp.12-17
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• 2002

Simultaneous determination of nine water-soluble vitamins contained in multi-nutrient tablets was carried out by reversed phase high-performance liquid chromatography (RP-HPLC) equipped with analytical $C_{18}$ column and UV (270 nm) detector. Those standard vitamins were successfully separated within 23 minutes by gradient elution with solvent A (0.5 M potassium phosphate monobasic) and solvent B (0.25 M potassium phosphate monobasic-methanol, 1:1). Calibration curves showed good linealities with correlation coefficients (> 0.92) in tested ranged respectively. The detection limits were considered to be 2.1 ng for ascorbic acids 60 ng for Vit B$_{6}$ 3 ng for p-aminobenzoic acid, 9 ng for niacinamide, 9 ng for thiamin, 5.0 ng for folic acid and 1.5 ng for riboflavin at 0.05 a.u.f.s. Solid phase extraction through Sep-Pak (C$_{18}$ ) cartridge was successfully applied for purification of water soluble vitamins in commercial multi-nutrient tablets.ts.

• Natural Product Sciences
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• 제16권2호
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• pp.123-132
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• 2010

The aim of the present study was to investigate whether self-fermented pine extract for 2 years (SFPE2) and ethyl acetate (EtOAc) fraction from self-fermented pine needle extract may affect the contractility of the isolated aortic strips and blood pressure of normotensive rats. SFPE2 ($360-1440\;{\mu}g/mL$) significantly depressed both phenylephrine ($10\;{\mu}M$)- and high potassium (56 mM)-induced contractile responses of the isolated rat aortic strips in dose-dependent fashion. The EtOAc-fraction ($400\;{\mu}g/mL$) also inhibited both phenylephrine ($10\;{\mu}M$)- and high potassium (56 mM)-induced contractile responses. Also, in anesthetized normotensive rats, intravenous injection of the EtOAc fraction (1.0~10.0 mg/kg) dose-dependently elicited hypotensive responses. The EtOAc fractions (1.0 and 3.0 mg/kg/30 min) inhibited norepinehrine-induced pressor responses. Intravenous infusion of SFPE2 fraction (3.0 and 10.0 mg/kg/30 min) also inhibited norepinehrine-induced pressor responses in both anesthetized spontaneously hypertensive rats (SHRs) and normotensive rats. In conclusion, these results suggest that both SFPE2 and the EtOAc fraction cause vascular relaxation in the aortic strips isolated from normotensive rats and SHRs as well as vasodepressor responses. Based on these experimental data, it seems that SFPE2 or the EtOAc fraction possesses active antihypertensive components, which are available to prevent or treat hypertension in future.

• 대한금속재료학회지
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• 제48권8호
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• pp.724-729
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• 2010

The effect of potassium permanganate ($KMnO_4$) in an electrolyte on the corrosion performance of magnesium alloy coated by micro-arc oxidation (MAO) has been investigated in this study. For this purpose, MAO coating was carried out on the present sample under AC condition in an alkaline silicate electrolyte with and without $KMnO_4$. Irrespective of the addition of $KMnO_4$, it was found from structural observation that the ceramic coating layers consisted of inner and outer layers. In the sample processed in the electrolyte with $KMnO_4$, the outer layer became dense and even contained a number of $Mn_2O_3$ atoms, resulting in high corrosion resistance. Based on the results of a potentiodynamic polarization test, it was confirmed that the coating layer formed in the electrolyte with $KMnO_4$exhibited better corrosion resistance than that without $KMnO_4$. The high corrosion resistance of the MAO-treated magnesium alloy was explained in relation to the equivalent circuit model.

• 한국인쇄학회지
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• 제14권2호
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• pp.37-49
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• 1996

The practical lith developer is a hydroquinone solution of moderate alkalinity and low free-sulfite ion concentration with potassium bromide as the restraining agent. In the study on composition of ilth developer to promote high sensitivity, high contrast and long term preservation or use, a new composition of lith developer, namely PK lith developer, was developed and of was found that PK lith developer was superior to the lith developer which was commercially available in terms of contrast, speed and preservation. This paper also describes studies on the addition of hdydrazine to PK lith developer, which have led to further improvements in the system.

• Asian-Australasian Journal of Animal Sciences
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• 제2권1호
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• pp.7-16
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• 1989

To determine the effect of sodium plus potassium to chloride ratio and lysine level on blood pH, blood acid-base parameters, lysine-arginine antagonism and growth performance, four hundred and thirty two chicks of 3 days age were used in a completely randomized $3{\times}3$ factorial experiment. Variables contained three levels of lysine (0.8, 1.2 and 1.6%) and dietary electrolyte (100, 200 and 300 mEq/kg). Birds fed 200 mEq/kg and electrolyte had the best growth rate and feed efficiency, followed by those fed 300 mEq/kg and 100 mEq/kg electrolyte. It is proposed that high levels of dietary electrolyte may improve the growth of chicks fed diets containing excess lysine by increasing lysine catabolism. High or low levels of lysine and dietary electrolyte resulted in higher mortality than those of optimum level (1.2%) of lysine and 200 mEq/kg of electrolyte balance. When the electrolyte level was increased, the pH, $pCO_2$, base excess, $HCO_3{^-}$ and total $CO_2$ of blood plasma were increased. The utilization of nutrients was changed when the electrolyte and lysine were manipulated. Plasma chloride tended to be greater in chicks receiving high chloride diet and was the highest in chicks fed the high lysine diet. Plasma sodium and potassium were unaffected by dietary lysine. Diet containing high lysine decreased the level of arginine and excess dietary electrolyte increased arginine level in plasma. It may be concluded that cation supplementation tended to alleviate the lysine-arginine antagonism but chloride exacerbated. Tibia bone length and ash contents were significantly affected by electrolyte balance and lysine level.

• The Korean Journal of Physiology
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• 제25권1호
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• pp.69-79
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• 1991

To evaluate the acute and chronic effects of potassium on aldosterone response to different amounts of sodium intake, two series of experiments were conducted. In the first series of experiments, when the plasma K level was increased acutely by KCI infusion $(20\;{\mu}g/kg/min\;for\;20 min)$, plasma aldosterone concentration increased in both low Na and high Na groups. However, the aldosterone response to K infusion was significantly greater in the low Na than in the high Na groups. In the second series of experiments, rats fed a high K diet chronically showed a significantly higher plasma K level than those fed a low K diet. However, plasma Na level was maintained relatively constant independent of the Na intake. Both the plasma renin activity (PRA) and aldosterone levels were inversely related to the Na intake. There was a highly positive correlation between aldosterone level and PRA over a wide range of sodium intakes. However, the slope of the correlation line was distinctly steeper in the K-repleted than in the K-depleted rats. The above results indicate that the adrenotropic action of acute K load was augmented in the presence of high plasma renin levels. However, when plasna K level was elevated chronically by a high-K diet, aldosterone secretion was markedly stimulated, although the plasma lenin levels were suppressed.

• 한국의류학회지
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• 제21권5호
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• pp.911-921
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• 1997

Recently the interest in natural dyeing has been increased because of the color clarity, natural grace and reactionism in fashion. Indigo dyeing, safflower dyeing and Gal-ott in Cheju-Do become generally known, so the study about the natural dyeing is continued with national intrust and support. In this study, 1 used artemisia for various dyeing tests because we can get it easily. 1 tested the dyeability in wool as well as cotton and silk with wormwood in natural dyeing material. I also dyed nylon with the same material for the comparison of the molecular structure. The mercerization and the chitosan treatment were done in cotton to improve the low dyeability in the natural dyeing. The result of this study are as follows; We have to dye repeatedly to get deep color in natural dyeing, and mordant treatment brought good result in color difference and dyeing fastness. 1. Compared with silk, wool and nylon, the dyeability of cotton was the worse. The color difference of cotton was 18.81 without mordants , and 24.05 with mordant. The dyeability of cotton was much increased by mordants such as potassiumdichromate, copper sulfate, iron sulfate and salt water. The color of cotton was turned into yellow-green in potassium dichromate and yellow-green with deep green in copper sulfate. The mercerization and the chitosan treatment of cotton made the improvement in color, dyeability, laundering fastness, abrasion fastness. 2. The color difference of silk was 3 times as high as cotton. It showed the similar degree with the chitosan treated-cotton. That is to say, silk had good dyeability because it contains amino group and carboxyl group. The dyebility of silk was increased by a mordant such as iron sulfate, potassium dichromate and salt water, Drycleaning fastness showed 5 grade, abrasion-fastness was high over 4~5 grade and sunlight fastness showed 1 grade in all case. 3. The color difference of wool was the best among four fabrics because of 18 kinds of amino acids. It is considered that the sulfate of wool has the polarity and help metal- mordants get the better dyeability such as potassium dichromate, iron sulfate, copper sulfate, and aluminum chloride. The color was reddish-green in potassium dichromate, yellow.greenin iron sulfate and copper sulfate, and yellow in the rest mordants. Drycleaning fastness of wool showed over 4~5 grade, abrasion fastness 5 grade. Sunlight-fastness 1 grade. 4. The dyeability of nylon was almost same because of the similar molecular structure with silk. The clarity of color was poor. The color was yellow-green in copper sulfate and yellow in the rest mordants. Laundering fastness and abrasion-fastness of nylon was good. Sunlight- fastness represented 1 grade.

• 대한수의학회지
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• 제35권2호
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• pp.245-254
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• 1995

The density of ATP-sensitive potassium($K_{APT}$) channels, that open as intracellular ATP concentration falls below a critical level, is very high in skeletal muscle surface membrane and those high density may imply that $K_{ATP}$ channels have very important physiological roles. To elucidate a role of $K_{ATP}$ in relation to fatigue, the modulating effects of potassium channel openers and blockers on the fatigue velocity(FV) of mouse extensor hallucis longus muscle(EHL) were investigated in vitro. Twitch contraction was induced by an electrical field stimulation (EFS: 24-48V, 20ms, 0.2-4Hz) and resulting contraction force was isometrically recorded. The twitch forces were gradually decreased to 25% of initial contraction force(ICF) in $37.52{\pm}1.55sec$($mean{\pm}s.e.m.$, n=135), indicating the fatigue phenomena. The mean velocity for development of the fatigue was measured during the period that twitch force decreased to half($FV_{0/0.5}$) and during the period from half to 25%($FV_{0.5/0.25}$) of ICF. The fatigue was induced once every one hour and the tissue response was stable for up to 4 hours. In control condition, ICF was $5.8{\pm}0.12g$ (n=144) and decreased to 50% of ICF with the mean fatigue velocity of $0.182{\pm}0.006g/sec$($FV_{0/0.5}$, n=135) and from 50% to 25% of ICF with $0.084{\pm}0.004g/sec$($FV_{0.5/0.25}$, n=135). Cromakalim($50{\mu}M$) significantly increased $FV_{0.5/0.25}$(n=4). Glibenclamide($IC_{50}>50{\mu}M$), $Ba^{2+}$($IC_{50}=10{\mu}M$), 4-aminopyridine($FV_{0/0.5}$, $IC_{50}=0.5mM$; $FV_{0.5/0.25}$, $IC_{50}=2mM$) decreased both $FV_{0/0.5}$ and $FV_{0.5/0.25}$ concentration-dependently up to 75%. $TEA^+$(30mM), E-4031($10{\mu}M$), tolbutamide(1mM) decreased $FV_{0.5/0.25}$, but apamin(300nM) and $TEA^+$(10mM) showed no significant effects. Our results suggest that activation of the $K_{ATP}$ channels may be major cause of $K^+$ outflux during development of the fatigue and the isolated EHL muscle could be an useful experimental preparation in studying the fatigue phenomena in skeletal muscle. In addition, the possibility of activation of delayed rectifier during the fatigue development remains to be studied further.

• Journal of Ginseng Research
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• 제2권1호
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• pp.35-57
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• 1977

4년생 인삼 식물을 재료로하여 계절에 따르는 영양 염류 흡수와 건물 생장량과의 관계를 해석하였다. 인삼포의 토양에 시비한 영양 염류는 계절에 따라 감소되었는데 약토구보다 무기비료 구의 잔존량이 적었다. 당년에 시비한 비료의 시비량에 따른 차이는 건물 생장에는 영향을 미치지 않았다. 단위 건물량당 영양염류의 함량은 속효성 비료인 화학비료를 시비하면 생육 초기(5월 16일)에, 지효설 비료인 약토를 시비하면 생육 후기(8월 21일)에 함량차가 나타났다. 단위 건물량당의 질고, 인산 및 가리 함량의 계절변화는 잎, 줄기, 뿌리가 5월 중순에 많은 양을 함유하였지만 6월 중순에 급감되고 그 이후는 일, 줄기에서는 걸감하고 뿌리에서는 증가되었다. 지상부의 생육기간중에는 뿌리속의 영앙 염류가 지상기관으로 전류되었지만 지상부 생육이 완료되면 흡수된 염류가 뿌리에 저장되었 다. 개체당 영양 염류함량의 계절변화는 생육이 완료된 지상부 기관에서는 그 변화가 없고 뿌리에서는 S자 곡선에 따라 생육이 완료될 때까지 증가되었다. 영양염류의 종류에 따른 흡수비로서 M/P는 높았고 N/K는 낮았다. 수광량이 많을수록 잎의 질소, 인산, 가리 함량은 낮아졌고, 줄기는 염류에 따라 함량 차를 보였다.