• The Korean Journal of Physiology
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• v.9 no.2
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• pp.33-39
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• 1975

Changes of urinary aldosterone excretion, concurrent sodium and potassium excretion following furosemide administration were studied in normotensive young Korean with high sodium intake, moderate sodium restriction and marked sodium depletion. After intravenous injection of furosemd 40mg, plasma and urine samples were collected at every thirty minutes for two hours. Plasma-and urinary aldosterone, electrolyte concentration and urine flow rate were measured by means of radioimmunoassay or flamephotometry. Relations of urinary aldosterone to concurrent sodium or potassium/sodium ratio, and of urinary aldosterone to concurrent plasma aldosterone activity were studied. Following were the results: 1. Furosemide administration resulted in a increased urinary aldosterone concentration and unchanged or somewhat decreased sodium concentration in course of time after the injection. 2. Urinary potassium concentration showed initial decrease and subsequent increase in course of time after furosemide administration and it resulted in a gradual increase in urinary potassium/sodium ratio. 3. Studying the relations between urinary aldosterone excretion and potassium/sodium excretion ratio, or sodium excretion were meaningless because of the urinary flow rate after the injection was decreased with time course. 4. Furosemide administration showed a good relationship of urinary aldosterone concentration to concurrent potassium/sodium ratio rather than concurrent sodium concentration in subjects with sodium restriction, but no meaningful relationship was detected in subjects with high sodium intake because increasing rate of the ratio was not so wide. 5. Furosemide also resulted a reasonable relation of plasma aldosterone concentration to concurrent urinary aldosterone concentration especially during low sodium intake. 6. Above results suggested that relation of urinary aldosterone concentration to K/Na ratio following furosemide administration during sodium restriction is significant and has a benefit to reduce the variation induced by kalemic change showing in the diragram for daily aldosterone to sodium excretion.

• The Korean Journal of Pharmacology
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• v.8 no.1
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• pp.31-40
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• 1972

The author studied the actions of ouabain and diphenylhydantoin sodium on the ATPase activity in mitochondrial fraction isolated from rabbit heart and compared with that of quinidine. The results obtained are as follows: 1) In studying the $(Na^++K^+)-activated$ ATPase activity, the rabbit heart isolated was immediately frozen for 7-9 days (ageing of preparation) and thereafter the mitochondria1 fraction obtained by differential centrifugation technic was treated with solution A containing 0.15% deoxycholate for 24-48 hours at $-10^{\circ}C$ before using in experiment. These methods increased the activity ratio to 0.87-0.98. 2) The $(Na^++K^+)-activated$ ATPase activity in mitochondrial fraction of rabbit heart was not completely but markedly inhibited by ouabain. This inhibitory action of ouabain was moderately antagonised by $K^+$ concentration at constant Na concentration. 3) Diphenylhydantoin sodium in concentration of $5{\times}10^{-4}{\sim}10^{-3}M$ stimulated markedly not only $Mg^{++}-dependent$ ATPase activity but also $(Na^++K^+)$-activated ATPase activity and in concentration lower than $10^{-6}M$ had little effect. However, this effect of diphenylhydantoin was markedly increased in the presence of $Na^+$ alone rather than $K^+$ alone, but lesser than that effect in the presence of both $Na^+$ and $K^+$, together. The stimulating effect of diphenylhydantoin was specifically antagonized by ouabaion. 4) When the rabbits were intravenously injected with ouabain and diphenylhydantion respectively, $(Na^++K^+)-activated$ ATPase activity of rabbit heart of ouabain-treated group was much decreased and both $(Na^++K^+)-activated$ ATPase and $Mg^{++}-activated$ ATPase activity were moderately increased in diphenylhydantoin-treated rabbit group. 5) The $(Na^++K^+)-activated$ ATPase activity in mitochondrial fraction of rabbit heart was slightly inhibited by quinidine in high concentration of $10^{-4}M$, but nearly little effect was observed below the concentration of $5{\times}10^{-5}M$. 6) It might be possible to conclude that diphenylhydantoin specifically antagonised the action of ouabain on the membrane ATPase, which is different from the action of quinidine.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.5
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• pp.540-546
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• 2010

We investigated variations in alkaline phosphatase (APase) activity and alkaline phosphatase hydrolyzable phosphorus (APHP) in northern Gamak Bay from September to December 2009. Dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus (DIP) decreased gradually, and the DIN/DIP ratio was higher than the Redfield ratio (16) based on molecular concentrations during most of the observation period. The total APase (T-APase) activity increased with decreasing DIP concentration; i.e., the Relationship between T-APase and DIP showed a high negative correlation (r=-0.80, P<0.001), with APase activity being a good indicator of DIP limiting the Redfield ratio. The T-APase was positively correlated with the concentration of chlorophyll a (r=0.73, P<0.001). This suggests that a major portion of APase activity in northen Gamak Bay seawater is attributed to phytoplankton. The proportion of APHP among dissolved organic phosphorus (DOP) was low in September and high in November. Thus, APase-producing phytoplankton may be able to grow by utilizing APHP as a phosphorus source in autumn when DIP is limiting. Thus, APase activity and the use of DOP by phytoplankton may play an important role in the growth of phytoplankton under DIP limiting conditions such as those of northern Gamak Bay.

• Journal of Nutrition and Health
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• v.32 no.6
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• pp.713-725
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• 1999

Women have a greater incidence of coronary heart disease(CHD) after menopause. It relates to hormone imbalance-induced changes in known CHD risk factors, especially hyperlipidemia. Accordingly, once women are diagnosed, the rate of morbidity and mortality is greater than for men. Thus, preventive strategies are critical to improve the quality oflife in the later years for women. The purpose of ths study was to explore the difference of anthropometric, environmental factors and food behaviors between normocholesterolemia and hypercholesterolemia within postmenopausal women. The subjects were classified as normocholesterolemia and hypercholesterolemia based on the Guideline for Korean Hyperlipidemia. The results obtained are summarized as follows. The distributions of general characteristics such as age, family income, occupation status, age at menarche, and menopausal period were not significantly different between the normocholesterolemia group and hypercholesterolemia group. The anthropometric factors such as body mass index(BMI) and waist hip ratio(WHR) were not significantly different between the normocholesteroemia group and the hypercholesterolemia group but odds ratio of hypercholesterolemia group was higher than that of normocholesterolemia but not significant. Aerobic activity more than 1hours/day was significantly related to low serum cholesterol concentration. Eating behaviors related to regular meal time, regular breakfast habit, and slow meal speed were related to low serum cholesterol concentration. Eating the chicken without skin was significantly related to low serum cholesterol concentration. Our data indicate that desirable eating habit, aerobic activity more than 1hr/day are important factors of serum cholesterol concentrations in postmenopausal women. The result of this study provide information that is important in designing appropriate dietary guidelines for hypercholesterolemia in postmenopausal women.

• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.94-97
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• 1993

This study was to predict water activity of gelatinized model foods containing moisture, protein and starch with different concentration of humectants such as sodium chlorife and sucrose. The water activity of each samples were determinded by electrical hygrometry. The degree of lowering water activity in model foods with humectant solutions was following order as NaCl>sucrose. Model food $P_2S_1$ was predominant in depression of water activity by humectants than other model foods. The multiple regression equations between water activity and different humectants concentration, compositions and solution ratio of model foods were obtained and $R^2$ values were higher than 0.91.

• Journal of dental hygiene science
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• v.7 no.1
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• pp.9-12
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• 2007

Streptococcus mutans is the major causative factor in dental caries and has been known to induce dental caries by the process of initial attachment proliferation and acid production. The pH of Streptococcus mutans(S. mutans) media and glucosyltransferase(GTase) activity were determined to evaluate the anticariogenic activity of Dioscorea batatas and Prunella vulgaris hexane fraction. In the experiment of hexane fraction of Dioscorea batatas, the relative growth ratio(RGR) against Streptococcus mutans (S. mutans) was determined as 93% in concentration of 0.125 mg/ml, 100% in 0.25 mg/ml. The hexane fraction of Prunella vulgaris revealed relative growth ratio(RGR) against Streptococcus mutans (S. mutans) as 86% in concentration of 0.25 mg/ml, 100% in 0.5 mg/ml. The relative growth ratio(RGR) against of hexane fraction were determined as 92% in concentration of 0.25 mg/ml, 100% in 0.5 mg/ml. The acidities were pH 7.2 on Dioscorea batatas and 7.0 on Prunella vulgaris in 2.0 mg/ml in contrast to pH 5.6 on Dioscorea batatas and 5.2 on Prunella vulgaris in control. The inhibitory effect to activity revealed 35% on Dioscorea batatas and 25% on Prunella vulgaris in 2.0 mg/ml. The inhibitory effect of Dioscorea batatas was more potent than Prunella vulgaris.

• Journal of Nutrition and Health
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• v.27 no.9
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• pp.940-948
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• 1994

The present study was designed to determine if prenatal and postnatal Se nutriture affects Se concentration, glutathione peroxidase(GSHPx) activity and phospholipid distribution of the neonatal rat lung. Female SD rats were bred and fed a semipurified Se-deficient(0.04ppm, Se-) or a Se-adequate(0.5ppm, Se+) diet through pregnancy and lactation. On d 2 of lactation, maternal dietary Se had no significant effect on pulmonary Se concentration of pups. On d 16 of lactation, mean milk Se concentration in Se- dams was significantly lower than that in Se+ dams. Milk Se concentration was reflected on lung Se concentration and GSHPx activity of d 16 pups, which were dramatically decreased in Se- pups. In addition, pulmonary disaturated phosphatidyl choline/total phosphatidyl choline ratio was also significantly decreased in Se- pups, implying impaired function of pulmonary surfactant. These data indicate that adequate Se nutrition is important in the maturation of neonatal rat lungs.

• The Korean Journal of Nuclear Medicine Technology
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• v.22 no.1
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• pp.84-89
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• 2018

Purpose Renin is a proteolytic enzyme synthesized and secreted from epidermal(juxtaglomerular) cells in kidney. Renin acts on the renin substrate angiotensinogen to produce angiotensin I, and then angiotensin II is produced by the action of angiotensin converting enzyme. This causes the adrenal glands to boost blood pressure (vasoconstriction) and promote aldosterone secretion. While Plasma renin activity (PRA) is to test angiotensin I, the active renin concentration (ARC) is a renin test directly. They have different test methods and their own substrates. However, these two methods are sometimes interpreted as the same as a result. The purpose of this study was to evaluate the usefulness of the ARC test by comparing the results between PRA and ARC. Materials and Methods For the diversity of the experiment, 26 samples were requested to test with PRA(TFB company) and ARC(Cisbio company) to other institution. We compared and analyzed PRA(Immunotech company) and ARC(Cisbio company) tests using 28 samples from September $15^{th}$ to October $13^{th}$ in 2017. The statistical analysis method for PRA/ARC evaluated the usefulness using Microsoft Excel program by verifying a correlation analysis of Aldosterone/PRA ratio and a correlation analysis of Aldosterone/ARC ratio and conducting T-test. Results The regression equation of the PRA(Immunotech company)/ARC(Cisbio company), which was tested in the department, was y = 0.0619x + 0.4615 and the correlation coefficient was 0.73. The regression equation of the PRA(TFB company)/ARC(Cisbio company), which was tested in the other institution, was y = 0.0888x + 0.3316 and the correlation coefficient was 0.91. In addition, The regression equation of Aldosterone / PRA ratio and Aldosterone / ARC ratio was y = 0.875x - 11.688 and the correlation coefficient was 0.87. Plus T - test showed no significant difference (P>0.05). Conclusion Both tests showed a strong positive correlation, but this only represents the strength and direction of the relationship between the two tests. Furthermore, the actual results showed somewhat differences. It is presumed that the measured value was influenced by the endogenous renin group mass in the plasma, the condition of the enzyme reaction and the kind of the inhibitor. When the active renin concentration (ARC) test is performed, it is useful to distinguish between the two tests as they are complementary.

• Journal of Technology Innovation
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• v.13 no.3
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• pp.77-100
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• 2005

This paper analyzes the determinants of firm's innovative activity, using Korean Innovation Survey (KIS) dataset. Especially, we focused on the role of external networks by partners(other firms or research institutions) in performing innovative activities. The product innovation, product improvement, and process innovation are used as proxies for innovative activity. The explanatory variables such as market concentration ratio, lagged profitability, foreign ownership, export ratio, firm's age, formal R&D activity, and industrial R&D intensity are also considered. With data from 1,124 firms for the two years (2000-2001), we estimated the logistic regression model. The finding is that the determinants of firm's innovative activities differ by type of innovations. We also found that the innovative behavior of SMEs differs from that of large firms. The result confirms that external networks have a strong positive effect on innovative activity. However, the network effects by partners vary across both firm size and type of innovations.

• Korean Journal of Environmental Agriculture
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• v.28 no.4
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• pp.397-402
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• 2009

In Korea, salt stress is one of the major problems limiting crop production and eco-environmental quality in greenhouse soil. The objective of this study was to evaluate the effectiveness of organic residues (Chinese milk vetch, maize stalk, rice straw, and rye straw) for reducing salt activity in greenhouse soil. Organic residues was incorporated with salt-accumulated soil (EC, 3.0 dS $m^{-1}$) at the rate of 5% (wt $wt^{-1}$) and the changes of electrical conductivity (EC) was determined weekly for 8 weeks under incubation condition at $30^{\circ}C$. The EC, microbial biomass carbon (MBC), and water soluble ions in soil was strongly affected by C/N ratio of organic residues. After 8 weeks incubation, the concentration of water soluble $NO_3{^-},\;Ca^{2+}$, and $Mg^{2+}$ was significantly decreased in organic residues having high C/N ratio (maize stalk, rice straw, and rye straw) incorporated soil compared to organic residues having lower C/N ratio (Chinese milk vetch) incorporated soil. The EC value in Chinese milk vetch incorporated soil was higher than control treatment. In contrast, maize stalk, rice straw, and rye straw amended soil was highly decreased the EC value compared to control and Chinese milk vetch applied soil after 4 weeks incubation. Our results indicated that incorporation of organic residues having high C/N ratio (>30) could reduce salt activity resulting from reducing concentration of water soluble ions.