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검색결과 254건 처리시간 0.023초

Association Between Gastric Emptying Time and Incidence of Cardiovascular Diseases in Subjects With Diabetes

  • Park, Hyung-Min;Park, Seon-Young;Chung, Jin Ook;Cho, Dong Hyuk;Park, Chang-Hwan;Kim, Hyun-Soo;Chung, Dong Jin;Choi, Sung-Kyu;Rew, Jong-Sun;Chung, Min Young
    • Journal of Neurogastroenterology and Motility
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    • 제25권3호
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    • pp.387-393
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    • 2019
  • Background/Aims Delayed gastric emptying (GE) is associated with high morbidity and mortality in subjects with diabetes. The aim of this study is to investigate associations between GE time and the major cardiovascular events (coronary heart diseases and ischemic stroke) in diabetic subjects with upper gastrointestinal (UGI) symptoms. Methods Among 259 subjects with chronic UGI symptoms who underwent gastric emptying study (GES) over 13 years, 122 diabetic subjects without gastric surgery and/or rapid GE were enrolled in this study. We also gathered data about baseline demographics, clinical characteristics, estimated GE half-time (GE T½) and incidence of cardiovascular events following GES. Results The mean age of subjects was 64.0 ± 17.4 years. There were 86 women and 104 subjects with type 2 diabetes. There were 52 (42.6%) subjects with normal GE, 50 (41.0.%) subjects with mild delayed GE, and 20 (16.4%) subjects with marked delayed GE. During follow-up (median, 207 weeks), cardiovascular events occurred in 7 (13.5%) subjects with normal GE, 4 (8.0%) subjects with mild delayed GE and 7 (35.0%) subjects with marked GE (P = 0.015). Univariate analysis showed that GE T½ was significantly associated with incidence of cardiovascular events (crude OR, 1.74; 95% CI, 1.12-2.69; P = 0.014). In a multivariate model, association between GE T½ and incidence of cardiovascular events remained statistically significant after adjustment for baseline characteristics and comorbidities (adjusted OR, 1.94; 95% CI, 1.21-3.12; P = 0.006). Conclusion A delay of GE was associated with an increased incidence of cardiovascular events in diabetic subjects with chronic UGI symptoms.

Paper Chromatography 에 關한 硏究 (第 1 報) 毛細管 上昇에 關하여 (基一) (Study on the Paper Chromatography. Ⅰ. Capillary Ascending of Liguids)

  • 양재현;최규원
    • 대한화학회지
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    • 제3권1호
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    • pp.23-27
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    • 1954
  • The relation between the height of ascending solvents and its velocity were studied with strips of Toyo No. 50 filter paper. The filter paper strip of 3cm width and cat 30 cm length is hooked down or fixed between two sheets of glass plates inside a cylinder containing the solvent, in which the lower end of the strip is dipped. As the solvents, acetone, hydrochloric acid, water or mixtures of these are used. For short time intervals, Ostwald's folmula $h = Kt^n$ was found to be most suitable to express the relation between the height of the solvent front, h, and time, t. For longer time intervals, results will be discussed in the next paper. The mean values of the constant m in the above formula for pure acetone and pure water were 0.44 and 0.485, respectively, and that of K were 0.05 and 2.4, respectively. The time interval whose the above formula applies, for each solvent was 2 hours for the former, and a half hour for the later, respectively. The movement of solutes, such as $Cu^{++}$ and $Fe^{++}$ showed that the Rf values of solutes become constant values after a long periods; e.g., ca. 6 hours with 10N-HCl-Acetone (1 : 9) solvent.

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Effect of Clarithromycin on the Pharmacokinetics of Ambroxol in Rats

  • Lee, Chong-Ki;Choi, Jun-Shik
    • Journal of Pharmaceutical Investigation
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    • 제36권3호
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    • pp.157-160
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    • 2006
  • This study investigated the effect of clarithromycin on the pharmacokinetics of ambroxol in rats. The pharmacokinetic parameters of ambroxol in rats were determined after the oral administration of ambroxol (12 mg/kg) in the presence or absence of clarithromycin (5 or 10 mg/kg). Compared with the control (given ambroxol alone), coadministration of clarithromycin significantly (p<0.05 at 5 mg/kg; p<0.01 at 10 mg/kg) increased the area under the plasma concentration-time curve (AUC), peak plasma concentrations $(C_{max})$ and absorption rate constant $(K_a)$ of ambroxol. Clarithromycin increased the AUC of ambroxol in a dose dependent manner within the dose range of 5 to 10 mg/kg. The absolute bioavailability (AB%) of ambroxol in the presence of clarithromycin was significantly higher than that of the control (p<0.05 at 5 mg/kg; p<0.01 at 10 mg/kg), and the relative bioavailability (RB%) of ambroxol with clarithromycin was increased by 1.32-to 1.71-fold. However, there were no significant changes in time to reach peak concentration $(T_{max})$ and terminal half-life $(T_{1/2})$ of ambroxol in the presence of clarithromycin. Coadministration of clarithromycin enhanced the bioavailability of ambroxol, which may be due to the inhibition of intestinal and hepatic metabolism of ambroxol by CYP 3A4. Further studies for the potential drug interaction are necessary since ambroxol is often administrated concomitantly with clarithromycin in humans.

제주 해녀의 어획노력량 분석 (Analysis for Fishing Effort of Diving Women In Cheju-Do)

  • 정상철
    • 한국수산과학회지
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    • 제22권4호
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    • pp.196-200
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    • 1989
  • 최근 몇 년간 제주도의 소라 생산량이 급감하고 있는바, 그 원인 규명을 위한 목적으로 노력당 어획고의 변동 및 최대지속생산량을 추정하기 위하여, 1968년에서 1986년까지의 제주도 소라어획통계자료와 1984년에서 1986년까지의 동귀리(복제주군 애월읍) 어촌계의 작업일지를 분석하였으며, 그 결과는 다음과 같다. 동귀리 어촌계의 경우, 소라 어획량은 제주도 총 소라 어획량의 $1\%$에 지나지 않으며, 실제 조업한 해녀수는 등록된 해녀수의 $53.4\%$인 63명이었다. 그리고 어획노력량으로서는 작업일수 보다 해녀수를 선정함이 양호하다. 제주도의 연간 최대지속생산량은 $2,500\~2,800$톤으로 추정되었으며 1982년에서 '85년까지의 어획량은 $3,100\~3,650$톤으로 과잉의 어획시기였고, 그로 인해 1986년은 매우 감소한 1,400톤이었다. 이전 상태로 어업을 지속할 경우 매우 심각한 상태에 도달할 것으로 예상된다.

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Pharmacokinetic-Pharmacodynamic Modeling for the Relationship between Glucose-Lowering Effect and Plasma Concentration of Metformin in Volunteers

  • Lee, Shin-Hwa;Kwon, Kwang-il
    • Archives of Pharmacal Research
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    • 제27권7호
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    • pp.806-810
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    • 2004
  • Metformin is a biguanide antihyperglycemic agent often used for the treatment of non-insulin dependent diabetics (NIDDM). In this study, the pharmacokinetics and pharmacodynamics of metformin were investigated in Korean healthy volunteers during a fasting state for over 10 h. In order to evaluate the amount of glucose-lowering effect of metformin, the plasma concentrations of glucose were measured for a period of 10 h followed by the administration of metformin (oral 500 mg) or placebo. In addition, the concentration of metformin in blood samples was determined by HPLC assay for the drug. All volunteers were consumed with 12 g of white sugar 10 minutes after drug intake to maintain initial plasma glucose concentration. The time courses of the plasma concentration of metformin and the glucose-lowering effect were analyzed by nonlinear regression analysis. The estimated $C_{max}$, $T_{max}$, $CL_{t}$/F (apparent clearance), V/F(apparent volume of distribution), and half-life of metformin were 1.42$\{pm}$0.07 $\mu\textrm{g}$/mL, 2.59$\{pm}$0.18h, 66.12$\{pm}$4.6 L/h, 26.63 L, and 1.54 h respectively. Since a significant counterclock-wise hysteresis was found for the metformin concentration in the plasma-effect relationship, indirect response model was used to evaluate pharmacodynamic parameters for metformin. The mean concentration at half-maximum inhibition $IC_{50}$, $k_{in}$, $k_{out}$ were 2.26 $\mu\textrm{g}$/mL, 83.26 $H^{-1}$, and 0.68 $H^{-1}$, respectively. Therefore, the pharmacokinetic-pharmacodynamic model may be useful in the description for the relationship between plasma concentration of metformin and its glucose-lowering effect.

제초제 quinclorac의 토양컬럼 중 용탈 (Leaching of the herbicide quinclorac in soil columns)

  • 안기창;경기성;이재구
    • 농약과학회지
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    • 제4권4호
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    • pp.19-25
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    • 2000
  • 유리컬럼에 논토양을 인위적으로 충전시킨 후 3가지 방법 [흡착제가 없는 quinclorac (T-1), 활성탄에 흡착된 quinclorac (T-2), 소석회와 활성탄의 혼합물에 흡착된 quinclorac (T-3)]으로 [$^{14}C$]quinclorac을 처리한 다음 벼재배 유무에 따른 용탈시험을 17주 동안 수행하였다. 무재배 경우 토양컬럼을 통하여 용탈된 T-1, T-2, T-3의 $^{14}C$ 방사능의 양은 각각 총처리 방사능의 약 81.1%, 27.8%, 그리고 48.0%였으며, 벼 재배의 경우에는 각각 약 36.8%, 9.6%, 그리고 11.0%였다. 이는 벼 재배와 흡착제의 첨가가 quinclorac의 용탈을 현저히 경감시켰음을 시사하였다. 모든 처리구에서 벼에 의해 흡수이행된 방사능은 각각 총처리 방사능의 13.6%, 11.0%, 그리고 13.9%였다. 용탈시험 종료 후 토양에 잔류한 $^{14}C$ 방사능의 양은 벼를 재배한 토양컬럼에서 각각 36.3%, 73.7%, 그리고 61.8%였으며, 벼를 재배하지 않은 토양컬럼에서는 각각 19.7%, 71.1%, 그리고 52.3%였다. T-1과 T-3에서 벼에 의해 흡수 이행된 $^{14}C$ 방사능은 시험기간중 여러 작용에 의하여 대기중으로 휘발 또는 방출되었다. Leachate의 방사능중 수상에 분포된 양은 모든 시료에서 전체 방사능의 7% 이하이었으나, 벼 재배 경우에서는 용탈 기간이 증가할수록 점차 증가하여 극성분해산물의 형성을 시사하였다.

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Li 도핑된 NiO 합성 및 열전식 수소센서에의 적용 (Synthesis of Li-doped NiO and its application of thermoelectric gas sensor)

  • 한치환;한상도;김병권
    • 한국수소및신에너지학회논문집
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    • 제16권2호
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    • pp.136-141
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    • 2005
  • Li-doped NiO was synthesized by molten salt method. $LiNO_3$-LiOH flux was used as a source for Li doping. $NiCl_2$ was added to the molten Li flux and then processed to make the Li-doped NiO material. Li:Ni ratios were maintained from 5:1 to 30:1 during the synthetic procedure and the Li doping amount of synthesized materials were found between 0.086-0.190 as a Li ion to Ni ion ratio. Li doping did not change the basic cubic structural characteristics of NiO as evidenced by XRD studies, however the lattice parameter decreased from 0.41769nm in pure NiO to 0.41271nm as Li doping amount increased. Hydrogen gas sensors were fabricated using these materials as thick films on alumina substrates. The half surface of each sensor was coated with the Pt catalyst. The sensor when exposed to the hydrogen gas blended in air, heated up the catalytic surface leaving rest half surface (without catalyst) cold. The thermoelectric voltage thus built up along the hot and cold surface of the Li-doped NiO made the basis for detecting hydrogen gas. The linearity of the voltage signal vs $H_2$ concentration was checked up to 4% of $H_2$ in air (as higher concentrations above 4.65% are explosive in air) using Li doped NiO of Li ion/Ni ion=0.111 as the sensor material. The response time T90 and the recovery time RT90 were less than 25 sec. There was minimum interference of other gases and hence $H_2$ gas can easily be detected.

2005${\sim}$2006년 모 대학 부속한방병원 학생건강클리닉에 내원한 외래 환자 실태조사 (Research on the Actual Conditions of the Outpatients who Visited the Pediatrics Department in $\bigcirc\;\bigcirc$ University Oriental Medicine Hospital between 2005 and 2006)

  • 윤경희;고덕재;김덕곤
    • 대한한방소아과학회지
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    • 제21권3호
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    • pp.125-143
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    • 2007
  • Objective The purpose of this study was to investigate health and life style of pediatric outpatients who visited the oriental hospital. Methods The study was composed of 363 students from elementary school, middle school and high school who visited the pediatrics department in $\bigcirc\;\bigcirc$ university oriental medicine hospital between 2005 and 2006. Results 1. The group wasconsisted with 56% of male and 44% of female student and for the age distribution, 7.4% were elementary school students, 55.6% were middle school students, and 36.9% were high school students. 2. Usually the eldest child tends to visit hosipital more than the younger ones. 3. More than a half of those students' parent had University education or beyond that. 4. There were more students who had below the level of the height-weight curve than in the higher level. 5. The average study hours of the students were 3.67 hours. An average sleep hours was 6.18 hours. An average exercise hour was 1.16 hours and an average time for watching TV was 1.71 hours. 6. Many students had hard time to concentrate on the studying for a long time. 7. For the question about the reason why they got the poor grade, they answered because of the lower concentration, and they didn't put much effort on the studying. The most they concern about was their grade. 8. Most of the students who visited the clinic said they did not feel refreshed when they woke up in the morning, and, many of them said that they don't feel okay. 9. More than an half of the students wear glasses. 10. More than an half of the students answered that they often catch a cold when the weather changes a lot. 11. A lot of them had some digestive problems. 12. As they getting older, they said they often feel back pain and shoulder pain. 13. Many students felt irritated and got mad easily. Many of them felt bored about their study and stressed out because of their tests and the university entrance exams. 14. Most of the female students answered that they have irregular period or cramps. 15. 21% of them usually skip breakfast. 16. Many students enjoyed snacks. Most of them enjoyed snacks after school. As they go into higher grade, they would like to eat at night especially cookies, bread and fruits. Conclusions Further studies with larger sample size of students will be neededfor accurate results, and it would be better if we can compare the conditions of the students before treatments and after those.

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극저주파 영역에서의 전자파 노출에 관한 조사연구 (Measurement and Personal Exposure Assessment of Extremely Low Frequency(ELF) Electromagnetic Fields(EMF))

  • 김윤신;김수연;박지연;최원욱
    • 한국환경보건학회지
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    • 제23권1호
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    • pp.55-61
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    • 1997
  • This study was executed for the purpose of investigation of the EMFs exposures of personal and electronic environment. This study examines ELF-EMFs of electric appliances, subways and occupational and non-occupational human exposures, using EMDEX II (for 40 - 800Hz, Enertech Consultant, Inc.), from October 1995 to March 1996. Among the electric appliances examined, a massage unit showed the highest mean value of 247.07 $\mu$T, followed by an electric blanket of 5.24 $\mu$T. Indoor levels of EMF in subways exceerlcd 0.2 $\mu$T of the Swedish Guideline. The mean personal exposure levels of occupational group were 0.18 $\mu$T, while the personal EMF level of non-occupational group were 0.07 $\mu$T. Occupational group were exposed more highly while at work. However, the EMF levels during nonwork and sleep exposures between occuptional group and nonoccupational group were about the same. Estimates of time-intergrated exposure indicated that utility-specipic job classifications received about one-half or more of their total exposure on the job. Finally, this study would provide significant data for future research for exposure to magnetic fields, and more detailed study and research are necessary.

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

  • 디펜드라 쿠마 아리얼;오수연;조종태;김형건;김윤균
    • Journal of Pharmaceutical Investigation
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    • 제37권6호
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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.