• Title/Summary/Keyword: Half Life

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Parent-Child Difference in Attitudes, Resources, and Constraints, and the Impacts of these Factors on Generational Proximity in the United States and Japan (노인 부모와 자녀 사이의 지리적 근접성에 대한 연구 : 미국과 일본의 사례를 중심으로)

  • 박경숙
    • Korea journal of population studies
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    • v.20 no.2
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    • pp.67-98
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    • 1997
  • This study examines multi-level factors geographic proximities between elderly parents and their children in the United States and Japan. Despite their similar economies, the United States and Japan show a significant difference in their patterns of generational proximity. In 1993, half of US non-Hisapnic white parents aged 70 or over lived separately but within 10 miles of their nearest children and a majority of them lived far from their non-nearest children. The family geographic network for Japanese elderly parents is more hierarchial. In 1989, 74 percent of Japanese parents aged 70 and over lived with their nearest children but most of them lived far from their non-nearest children. To explain this distinctive pattern of inter- and intra-family differences in generational proximities in the two societies, this study employs a multi-level analysis which compares the relative importance of life course conditions of elderly parents and their children and economic and ecological characteristics of elderly parent's places of residence in influencing generational proximities.

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Pharmacokinetics of Paclitaxel in Rabbits with Renal Failure Induced by Folic Acid (신장장애 가토에서 파크리탁셀의 약물동태)

  • Jung, Eun Jung;Gwak, Hye Sun;Choi, Jun Shik;Lee, Jin Hwan;Li, Xiuguo
    • Korean Journal of Clinical Pharmacy
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    • v.12 no.2
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    • pp.91-95
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    • 2002
  • The pharmacokinetics of intravenous paclitaxel (1 mg/kg) were investigated in rabbits with renal failure induced by folic acid. The area under the plasma concentration-time curve from time zero to time infinity (AUC) of paclitaxel was significantly (p<0.05) greater in rabbits with severe renal failure induced by folic acid $(1030\pm382)$ compared to that in rabbits with in moderate renal failure induced by folic acid $(780\pm209\;ng/ml{\cdot}hr)$. The apparent volume of distribution (Vd) $(0.008\pm0.002\;L/kg)$ and the elimination rate constant $(\beta)\;(0.09\pm0.025\;hr^{-1})$ of paclitaxel in rabbits with severe renal failure were significantly (p<0.05) smaller and slower respectively than those of control rabbits $(0.016\pm0.004\;L/kg,\;0.12\pm0.03\;hr^{-1})$, but not significantly different compared with that in rabbits with moderate renal failure $(0.010\pm0.003\;L/kg,\;0.10\pm0.026\;hr^{-1})$. total body clearance (CL) of paclitaxel in rabbits with severe renal failure $(0.97\pm0.183\;L/hr/kg)$ was significantly (p<0.05) slower than that in control rabbits $(1.68\pm0.440\;L/hr/kg)$, but not significantly different compared with that in rabbits with in moderate renal failure $(1.28\pm0.311\;L/hr/kg)$. The terminal half-life ($t_{1/2}$) of paclitaxel in rabbits with severe renal failure $(7.46\pm2.16\;hr)$ was significantly (p<0.05) longer than that in control rabbits $(5.75\pm1.44\;hr)$, but not significantly different compared to that in rabbits with moderate renal failure rabbits $(6.67\pm1.76\;hr)$. The above data could be at least partly decrease in due to paclitaxel excretion in rabbits with renal failure, since $7-15\%$ of interavenous paclitaxel was excreted via kidney as unchanged forms plus its metablites.

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Bioequivalence of Cefaclor (250 mg) Capsule (세파클러 250 mg 캅셀의 생물학적 동등성)

  • Yun, MH;Kim, HS;Choi, YP;Kwon, KI
    • Korean Journal of Clinical Pharmacy
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    • v.12 no.2
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    • pp.71-75
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    • 2002
  • This study was carried out to compare the bioavailability of $Ceclex^{(R)}$ (test drug, cefaclor 250 mg/capsule) with that of $Ceclor^{(R)}$ (reference drug) and to estimate the pharmacokinetic parameters of cefaclor in healthy Korean adult. The bioavailability was examined on 20 healthy volunteers who received a single dose (250 mg) of each drug in the fasting state in a randomized balanced 2-way crossover design. After dosing, blood samples were collected for a period of 6hours. Plasma concentrations of cefaclor were determined using HPLC with UV detection. The pharmacokinetic parameters $(AUC_{0-6hr},\;C_{max},\;T_{max},\;AUC_{int},\;K_e,\;t_{1/2},\;Vd)$ F, and CL/F) were calculated with non-compartmental pharmacokinetic analysis. The ANOVA test was utilized for the statistical analysis of the $T_{max},\;log-transformed\;AUC_{0-6hr}\;log-transformed\;C_{max},\;t_{l/2},\;V_d/F$, and CL/F. The ratios of geometric means of AUC0-6hr and $C_{max}$ between test drug and reference drug were $103.2\%\;(6.74\;{\mu}g{\cdot}hr/ml\;vs\;6.53{\pm}g{\cdot}hr/ml)\;and\;100.4\%\;(4.85\;{\mu}g\ml\;vs\;4.82\;{\mu}g/ml)$, respectively. The $T_{max}$ of test drug and reference drug were $0.9\pm0.38\;hr\;and\;0.83\pm0.34$ hrs, respectively. The $90\%$ confidence intervals of mean difference of logarithmic transformed $AUC_{0-6h},\;and\;C_{max}$ were log $0.98{\sim}log$ 1.08 and log $0.88{\sim}log1.15$, respectively. It shows that the bioavailability of test drug is equivalent with that of reference drug. The estimated half-life of this study was longer $(1.21\pm0.27\;hrs\;vs\;0.5-1\;hr)$, the Vd/F was larger $(68.89\pm25.72L$ vs 24.9L), and the CL/F was higher $(38.62\pm7.09\;L/hr$ vs 24.9 L/hr) than the previously reported values.

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Cloning and Expression of Thermostable $\beta$-Glycosidase Gene from Thermus filiformis Wai33 A1 in Escherichia coli and Enzyme Characterization

  • Kang, Sang-Kee;Cho, Kwang-Keun;Ahn, Jong-Kun;Kang, Seung-Ha;Han, Kyung-Ho;Lee, Hong-Gu;Choi, Yun-Jaie
    • Journal of Microbiology and Biotechnology
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    • v.14 no.3
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    • pp.584-592
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    • 2004
  • A thermostable $\beta$-glycosidase gene, tfi $\beta$-gly, was cloned from the genomic library of Thermus filiformis Wai33 A1. ifi $\beta$-gly consists of 1,296 bp nucleotide sequence and encodes a polypeptide of 431 amino acids. It shares a strong amino acid sequence similarity with the $\beta$-glycosidases from other Thermus spp. belonging to the glycosyl hydrolase family 1. In the present study, the enzyme was overexpressed in Escherichia coli BL21 (DE3) using the pET21b(+) vector system. The recombinant enzyme was purified to homogeneity by heat treatment and a $Ni^{2+}$-affinity chromatography. Polyacrylamide gel electrophoresis (PAGE) showed that the recombinant Tfi $\beta$-glycosidase was a monomeric form with molecular mass of 49 kDa. The temperature and pH range for optimal activity of the purified enzyme were 80- $90^{\circ}C$ and 5.0-6.0, respectively. Ninety-three percent of the enzyme activity was remained at $70^{\circ}C$ after 12 h, and its half-life at $80^{\circ}C$ was 6 h, indicating that Tfi $\beta$-glycosidase is highly thermostable. Based on its K_m$, or $K_{cat}K_m$, ratio, Tfi $\beta$-glycosidase appeared to have higher affinity for $\beta$-D-glucoside than for $\beta$-D-galactoside, however, $K_{cat} for \beta$-D-galactoside was much higher than that for $\beta$-D-glucoside. The activity for lactose hydrolysis was proportionally increased at $70^{\circ}C$ and pH 7.0 without substrate inhibition until reaching 250 mM lactose concentration. The specific activity of Tfi TEX>$\beta$-glycosidase on 138 mM lactose at $70{^\circ}C$ and pH 7.0 was 134.9 U/mg. Consequently, this newly cloned enzyme appears to have a valuable advantage of conducting biotechnological processes at elevated temperature during milk pasteurization in the production of low-lactose milk.

An Analysis of the Factors that Change the Science Academic Emotion of Elementary Students in Storytelling Classes Using Fairy Tales Connected to Exhibits in Science Museum (과학관 전시물 연계 동화 활용 스토리텔링 수업이 초등학생의 과학학습정서에 변화를 가져온 요인 분석)

  • Choi, So-Young;Shin, Youngjoon
    • Journal of Science Education
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    • v.43 no.3
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    • pp.300-317
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    • 2019
  • This study aims to find how storytelling classes using fairy tales related to science museum exhibits have an effect on positive experience about science. For this study, the theoretical background and preceding studies on the relevance of science education and literature were collected and based on the characteristics of assimilation and the educational value of assimilation, naturally connected to the exhibits in relation to their own life, so that individuals could explore science even out-of-school. Four types of activities were developed by linking four fairy tales mentioned in elementary school textbooks to the G science museum exhibits. Seven elementary school teachers verified the validity of the activity materials. Classes through the developed activity materials were conducted four times in a row, one and a half hours at every turn for 10 students. A positive experience about science test was conducted on the students in a study to confirm that this activity has caused significant changes in science academic emotion among sub-domains of positive experience about science. In order to find the factors that affected the science academic emotion, we interviewed the students in the study and their parents. The results of this study show that the use of fairy tales related to science museum exhibits has led to a significant change in science academic emotion by reducing the burden of learning through the exhibition experience at the science museum, which creates scientific curiosity and recognizes them as a playground.

Continuous Production of Authentic Human Growth Hormone from Methionyl Human Growth Hormone Using the Column Reactor of Immobilized Aminopeptidase M (고정화 Aminopeptidase M 컬럼 반응기를 이용한 메치오닐 인간성장호르몬으로부터 천연형 인간성장호르몬의 연속생산)

  • 이성희;김기태
    • KSBB Journal
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    • v.10 no.3
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    • pp.283-291
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    • 1995
  • The characteristics of aminopeptidase M(ApM) immobilized covalently on Cellufine Formyl and the continuous production of authentic human growth hormone(hGH) from methionyl human growth hormono(met-hGH) using the column reactor packed with immobilized ApM were investigated. Immobilized ApM with the proportion of 2.3mg ApM per 1g Cellufine Formyl gel had the highest met-hGH conversion activity. The optimum pH(7.0) and temperature($55^{\circ}C$) showed no appreciable difference between free and immobilized enzymes and the optimum temperature in continuous operation of the column reactor was also found to be $55^{\circ}C$. Under the conditions at which met-hGH was converted completely to hGH, the yield and productivity were about 77% and 0.8mg hGH/ml$.$h, respectively. In two column reactors of different sizes, met-hGH was converted to hGH with the same conversion rates and hGH yields at the same space velocities. The half-life of the reactor systems at $45^{\circ}C$ and $55^{\circ}C$ were projected from the continuous operations for 90 days to be 225 days and 81 days, respectively.

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Bioequivalence of Efexor® XR capsule to Venfaxine® OR tablet (Venlafaxine 75 mg) (이팩사® XR서방캅셀(벤라팍신, 75 mg)에 대한 벤팍신®OR서방정의 생물학적동등성)

  • Aryal, Dipendra Kumar;Oh, Soo-Yeon;Cho, Jong-Tae;Kim, Hyung-Gun;Kim, Yoon-Gyoon
    • Journal of Pharmaceutical Investigation
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    • v.37 no.6
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    • pp.397-402
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    • 2007
  • To evaluate the bioequivalence of two venlafaxine formulations, a standard 2-way randomized cross-over study was conducted in twenty-four healthy male Korean volunteers. A single oral dose of 75 mg of test formulation Venfaxine $OR^{(R)}$ (tablet) or reference formulation Efexor $XR^{(R)}$ (capsule) was administered with one-week washout period. Plasma concentrations of venlafaxine were assayed for over a period of 72 hours with a well validated method using liquid chromatography coupled to tandem mass spectrometry (LC-MS-MS). The $mean{\pm}S.D$. of maximum concentration $(C_{max})$ and elimination half-life $(t_{1/2})$ were $64.7{\pm}28.5$ ng/mL, $9.2{\pm}3.0$ h, and $67.2{\pm}30.2$ ng/mL, $9.9{\pm}3.5$ h for test and reference formulations, respectively. Time to reach maximum concentration $(T_{max})$ expressed in median value (range), for the test and the reference, were 10 h (6-14) and 8h (4-12), respectively. Similarly, area under the plasma concentration-time curve, from time zero to last sampling time $(AUC_t)$ and from time zero to time infinity $(AUC_{inf})$, for test and reference formulations were $1185{\pm}755$, $1326{\pm}896$ and $1124{\pm}737$, $1185{\pm}755$ $ng{\cdot}h/mL$, respectively. The parametric 90% confidence intervals on the mean of the differences between the two formulations (test-reference) of the log transformed values of $AUC_t$, and $C_{max}$ were 0.9630 to 1.1383 and 0.8650 to 1.0446, respectively. The overall results indicate that the two formulations are bioequivalent and can be prescribe interchangeably.

A Study on Dietary Behavior and Health Condition of Employees at Department Stores (백화점 종사자의 식행동과 건강상태에 관한 조사)

  • Kim, Hye-Kyung;Kim, Jin-Hee;Park, Young-Sook
    • Korean Journal of Community Nutrition
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    • v.13 no.3
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    • pp.374-385
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    • 2008
  • A study has been performed to provide the basic information about the current dietary habits, health related behaviors, and body indices and to bring forward the importance of this information to the people's attention based upon the relation between employee's life patterns and health conditions in their daily lives. Three hundred and five department store workers were examined from August 2006 to September 2006. With the average BMI values $23.9{\pm}2.2$ for males and $20.0{\pm}1.9$ for females, both gender groups were in normal, but 62.2% of the males were overweight and 15.4% of the females were under-weight. Regarding dietary and health related factors on how they perceive themselves, as normal were 204 (66.9%) the most and bad and very bad were respectively 43 (14.1%) and 5 (1.6%). Half of the subjects (43.2%) perceived sleeping hours to be insufficient, and 64.4% of them need to exercise regularly. As problems related to eating habits, they reported irregular meal times, overeating, preference of hot and spicy food, skipping meal, unbalanced meals. Regarding weight control they have attempted were the most (73.0%), after weight reduction, 51.2% of the subjects had side effects, such as gastrointestinal troubles, anemia, dizziness, sense of fatigue, constipation, physiological disorder, and diarrhea, etc. In the food habit score, it was shown that overall average score of the subjects was $62.63{\pm}9.86$ which is lower than other studies. Female ($62.76{\pm}10.15$) had better score than male ($61.67{\pm}8.06$). While the item with the highest point was eat all three meals of the day, that was the lowest point, exercise every day. The food habit score of the younger group had lower than older group, and also they preferred sweet foods to other group. The results suggest that nutrition education for workers at specific working fields needs to be more focused on the improvement of dietary habits and health status of workers.

Synthesis of L-threo-3,4-Dihydroxyphenylserine(L-threo-DOPS) with Thermostabilized Low-Specific L-Threonine Aldolase from Streptomyces coelicolor A3(2)

  • Baik, Sang-Ho;Yoshioka, Hideki;Yukawa, Hideaki;Harayama, Shigeaki
    • Journal of Microbiology and Biotechnology
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    • v.17 no.5
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    • pp.721-727
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    • 2007
  • Stability-enhanced mutants, H44, 11-94, 5A2-84, and F8, of L-threonine aldolase(L-TA) from Streptomyces coelicolor A3(2)(SCO1085) were isolated by an error-prone PCR followed by a high-throughput screening. Each of these mutant, had a single amino acid substitution: H177Y in the H44 mutant, A169T in the 11-94 mutant, D104N in the 5A2-84 mutant and F18I in the F8 mutant. The residual L-TA activity of the wild-type L-TA after a heat treatment for 20 min at $60^{\circ}C$ was only 10.6%. However, those in the stability-enhanced mutants were 85.7% for the H44 mutant, 58.6% for the F8 mutant, 62.1% for the 5A2-84 mutant, and 67.6% for the 11-94 mutant. Although the half-life of the wild-type L-TA at $63^{\circ}C$ was 1.3 min, those of the mutant L-TAs were longer: 14.6 min for the H44 mutant, 3.7 min for the 11-94 mutant, 5.8 min for the 5A2-84 mutant, and 5.0 min for the F8 mutant. The specific activity did not change in most of the mutants, but it was decreased by 45% in the case of mutant F8. When the aldol condensation of glycine and 3,4-dihydroxybenzaldehyde was studied by using whole cells of Escherichia coli containing the wild-type L-TA gene, L-threo-3,4-dihydroxyphenylserine(L-threo-DOPS) was successfully synthesized with a yield of 2.0 mg/ml after 20 repeated batch reactions for 100 h. However, the L-threo-DOPS synthesizing activity of the enzyme decreased with increased cycles of the batch reactions. Compared with the wild-type L-TA, H44 L-TA kept its L-threo-DOPS synthesizing activity almost constant during the 20 repeated batch reactions for 100 h, yielding 4.0 mg/ml of L-threo-DOPS. This result showed that H44 L-TA is more effective than the wild-type L-TA for the mass production of L-threo-DOPS.

A Study on Sensibility Approach in Industrial Design Focused on Industrial Design History from the 1960s to the 1980s (산업디자인의 감성적 접근에 관한 연구 - 1960-80년대 디자인사를 중심으로)

  • 김동하
    • Archives of design research
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    • v.17 no.3
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    • pp.293-302
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    • 2004
  • The austere standard for industrial design and the machine aesthetic reinforced modernism and lasted more than a half century. Pop art and Pop design movements, which were opposite of the elite culture, began to appear as anti-modernism in the late 1950s. With the development of technology, the movements helped to establish humanism design style that reflected the life style of young generation and their culture. From the 1960s. it was a try in order to fulfill psychologically users' needs beyond tasks for physical considerations. The efforts appeared as a various appearance in different contexts. It could settle down on industrial design, based on humanism both from the physical and psychological points ol views, through anti-modernism in the 1960s, commercialism, consumerism and hi-tech in the 1970s, and postmodernism in the 1980s. The design, as a specific style in industrial design, delivers both physical and psychological satisfaction to consumers by using a mixture of human emotions with high technology. Accordingly, this study is to find out and to define the design style that was applied by human emotion and sensibility in design history from the 1960s to the 1980s. It will be underpinnings for the next research about how the design style has developed nowadays.

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