• Title/Summary/Keyword: Prolongation

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Effects of Gamma-Irradiated Korean Ginseng on Fertility and General Reproductive Toxicity in Rats (방사선 조사 인삼이 랫드의 수태능 및 일반 생식독성에 미치는 영향에 관한 연구)

  • 박귀례;한순영;김판기;이유미;신재호;장성재
    • Toxicological Research
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    • v.17 no.2
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    • pp.97-106
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    • 2001
  • Korean ginseng products have been fumigated with ethylene oxide (EO) for sterilization and prolongation of storage periods. However, there had been controversies indicating that the consumption of food treated with EO might cause harmful effects in human. Since, in Korea the use of EO gas for food treatment was banned in 1991. Since then, irradiation technique has been developed as an alternative. This study was carried out to investigate the effects of irradiated ginseng on fertility, and reproductive and developmental toxicity. Either EO gas fumigated or gamma-irradiated ginseng was administered to male rats by oral gavage for 63 days during the premating period. Female rats were administered from 14 days before mating to day 20 of gestation or to day 21 of lactation. The exposure amount of irradiation used was 5, 10 and 30 kGy, respectively. There were no treatment related changes of darns in clinical signs, and parturition. No treatment related changes in food consumption, body/organ weights, male/female reproductive and fertility performances were observed. F1 fetuses showed no external abnormality. Reflex/sensory junctions, physical/behavioral development, and reproductive performance of F1 rats were not adversary affected. The results of this study show that gamma-irradiated ginseng, up to 30 kGy, has no adverse effects on the fertility, reproduction and development in Wistar rats.

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A Study on the Estimation of the Optimum Lifetime of Elevator Components for Elevator Accident Prevention (엘리베이터 사고예방을 위한 승강기 부품의 최적 수명 추정에 관한 연구)

  • Kim, Han-jin;Hwang, Min-soo;Choi, Og-man;Lee, An-ki;Kim, Jae-chul
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.8
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    • pp.1278-1284
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    • 2017
  • As of December 2016, there are 608,828 elevators in operation in Korea and 179,790 elevators in more than 15 years. 30.4% of all elevator are aging. Improved maintenance of the elevator and proactive replacement of the parts of the elevator can extend the lifetime of the elevator and ensure safety. An unclean environment reduces the lifetime of elevator parts. If you do not clean the environment and prevent preventive parts replacement, eventually shortening the lifetime of the parts connected to the failed part or causing more damage will result in greater economic loss. Also, the risk of elevator safety accidents due to failures of elevator parts will be increased accordingly. The study of optimum replacement time of elevator parts will contribute to prevention of safety accident of elevator and prolongation of lifetime of elevator through preventive replacement of elevator parts.

Studies on Efficacy of Combined Preparation of Crude Drugs(XXIII) -Analgesic, Anticonvulsive, Sedative, Antipyretic Actions of Yangkyuksanwhatang and its Effects on Isolated Ileum and Blood Vessel- (생약복합제제(生藥複合製劑)의 약효연구(藥效硏究) (제13보)(第13報) -양격산화탕(凉膈散火湯)의 진통(鎭痛) 항경련(抗痙攣) 진정(鎭靜) 해열(解熱) 작용(作用) 및 적출(摘出) 장관(腸管) 및 혈관(血管)에 미치는 영향(影響)-)

  • Hong, Nam-Doo;Kim, Jong-Woo;Song, Il-Byung;Won, Do-Hee;Kim, Nam-Jae;Kim, Jin-Sung
    • Journal of Pharmaceutical Investigation
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    • v.15 no.2
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    • pp.63-72
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    • 1985
  • Analgesic, anticonvulsive, sedative and antipyretic actions of Yangkyuksanwhatang which is composed of nine crude drugs including Rehmanniae Radix, and its effects on isolated ileum and blood vessel were investigated. The results of the studies were summerized as follows; 1. Analgesic and antipyretic effects were observed. 2. Suppressive actions were not shown on the convulsion induced by strychnine, but significant effects were noted on the convulsion induced by picrotoxin. 3. A prolongation of anesthetic time induced by pentobarbital sodium was significantly observed. 4. Relaxing actions were noted on the ileum of mice, and also, same effects were recognized on the contraction of the ileum due to acetylcholine chloride and barium chloride. 5. The expansion of blood vessels by relaxation of smooth muscle and hypotensive effects were noted.

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Block of hERG $K^+$ Channel by Classic Histamine $H_1$ Receptor Antagonist Chlorpheniramine

  • Hong, Hee-Kyung;Jo, Su-Hyun
    • The Korean Journal of Physiology and Pharmacology
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    • v.13 no.3
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    • pp.215-220
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    • 2009
  • Chlorpheniramine is a potent first-generation histamine $H_1$ receptor antagonist that can increase action potential duration and induce QT prolongation in several animal models. Since block of cardiac human ether-a-go-go-related gene (hERG) channels is one of leading causes of acquired long QT syndrome, we investigated the acute effects of chlorpheniramine on hERG channels to determine the electrophysiological basis for its proarrhythmic potential. We examined the effects of chlorpheniramine on the hERG channels expressed in Xenopus oocytes using two-microelectrode voltage-clamp techniques. Chlorpheniramine induced a concentration-dependent decrease of the current amplitude at the end of the voltage steps and hERG tail currents. The $IC_{50}$ of chlorpheniramine-dependent hERG block in Xenopus oocytes decreased progressively relative to the degree of depolarization. Chlorpheniramine affected the channels in the activated and inactivated states but not in the closed states. The S6 domain mutations Y652A and F656A partially attenuated (Y652A) or abolished (F656A) the hERG current block. These results suggest that the $H_1$ antihistamine, chlorpheniramine is a blocker of the hERG channels, providing a molecular mechanism for the drug-induced arrhythmogenic side effects.

Effects of Nitrogen and Potassium Sources on the Growth and Quality of Zoysia japonica Steud. (질소 및 가리 급원이 들잔디(Zoysia japonica Steud.)의 생육 및 품질에 미치는 영향)

  • 황규성;이용범;한동욱
    • Asian Journal of Turfgrass Science
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    • v.5 no.1
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    • pp.1-10
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    • 1991
  • The purpose of the experiment was to determine the effect of nitrogen sources (urea, ammonium sulphate, ammonium nitrate) and potassium sources (potassium chloride, potassium sulphate) on the growth and quality of Zoysia japonica Steud. This experiment was conducted at Seoul City University turf field from 1988 to 1989. The results of this experiment were summarized as follows; 1. Urea and Ammonium sulphate resulted in superior clipping yield compared to ammonium nitrate. The growth of rhizome and stolon increased significantly with urea forms, but ammonium sulphate treated plots exhibited the highest the growth rate of root. 2. Ammonium sulphate showed best turf color rating while ammonium nitrate resulted in the poorest. Prolongation of the green period showed longer in ammonium sulphate and urea treated plots than ammoium nitrate. 3. Urea and ammonium sulphate exhibited superior visible quality and shoot density compared to ammonium nitrate. 4. The uptake of mineral nutrient showed the highest concentration with urea plots. Surface soil pH was allowed to become slightly acid with the ammonium sulphate and potassium sulphate treatments, while the application of N and K sources did not cause significant differences in mineral element content in soil.

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Influences of Detention Time, Particle Size Distribution, and Filter Medium on Waterworks Sludges Dewatering (체류시간, 입도분포 및 여재가 정수 슬러지의 탈수에 미치는 영향)

  • Kim, Kwang-Soo;Lee, Jae-Bok
    • Journal of Korean Society of Water and Wastewater
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    • v.23 no.1
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    • pp.121-128
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    • 2009
  • Objectives of this study were to investigate influencing factors of detention time, particle size distribution, and filter medium characteristics for waterworks sludge dewatering. The stepped pressure filtration was carried out with lab scale apparatus and the filter press pilot test for dewatering was conducted at the water treatment plant. Effects of filter medium and polymer dose were examined through observing water content and dewatering velocity and cyclic dewatering rate with filter press pilot test. Relationships among detention time, particle size distribution and filtration resistance were analyzed. Prolongation of sludge detention time was found to cause blinding phenomenon in cake and filter medium and to decrease dewatering process efficiency. The average specific resistance increased according to detention time. In pilot test of dewatering for thickened sludge with Nylon Multi-NY840D and Nylon Mono-100% filter media, dewatering velocities were 0.92 and $0.93kg\;DS/m^2{\cdot}hr$ according to 0.1% polymer dose of dried solids weight base. And cyclic dewatering rates were 2.45 and $2.50kg\;DS/m^2{\cdot}cycle$ cycle for the Nylon Multi-NY840D and Nylon Mono-100% media. Dewatering velocity of polymer dosed sludge was observed to be higher than that of non-polymer sludge.

Effects on the Gamma Rays Scattered Backward by the Gold Cylinder on the Nuclear Energy Level (실린더 금속판에 의해 뒤쪽산란된 감마선이 핵에너지 준위에 미치는 효과)

  • Jeong, M.T.;Chol, N.G.;Cheoun, M.K.
    • Journal of the Korean Magnetics Society
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    • v.17 no.2
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    • pp.103-107
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    • 2007
  • When the gamma-ray source, $^{133}Cs$, embedded in a solid is placed at the center of a gold cylinder, the width of 81 keV level is shown to become narrower. This result implies a prolongation of the lifetime of that energy level. With a 0.5-mm-thick, 5-cm-long, 2-mm-diameter platinum cylinder, we obtain a width narrower by 6.1 % at 4.2 K.

The Study of Antithrombin III Deficiency in Patients with Recurrent Spontaneous Abortion (반복자연유산 환자에서 Antithrombin III 결핍증에 대한 연구)

  • Nam, Yoon-Sung;Cha, Kwang-Yul;Kim, Nam-Keun;Kang, Myung-Seo;Oh, Do-Yeon
    • Clinical and Experimental Reproductive Medicine
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    • v.28 no.4
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    • pp.301-305
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    • 2001
  • Objective : To analyze the antithrombin II deficiency in patients with recurrent spontaneous abortion. Material and Method: The blood samples were tested by chromogenic assay to evaluate the activity of antithrombin III. Results: There was only one case of antithrombin III deficiency. This patient experienced one neonatal death after delivery and one FDIU (fetal death in utero). And also this patient showed a lupus anticoagulant and the prolongation of PTT. Conclusions: Women with recurrent miscarriage who have no obvious identified cause should consider hematologic screening. Antithrombin III deficiency could be a cause of recurrent spontaneous abortion. But the incidence is very rare in Korean patients.

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Numerical Analysis of a Turbine Rotor Cascade with Unsteady Passing Wakes (비정상 후류를 지나는 터빈 동익 주위의 유동장 수치해석)

  • Lee, Eun-Seok
    • 유체기계공업학회:학술대회논문집
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    • 2006.08a
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    • pp.153-156
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    • 2006
  • A turbine stage consists of a stator and rotor. A stator provides the required inlet flow conditions so that a rotor can produce the necessary power. Passing wakes generated at the trailing edge of a stator make an interaction with a rotor. In the present study, this interaction flow mechanism is investigated using the numerical analysis. In case of the large gap distance between the stator and rotor, the stator and rotor flow analysis can be separated. First, only the stator flow field is solved. Second, the rotor flow field is solved including the passing wake information from the stator analysis. The passing wake experiences the shearing as it approaches to the rotor leading edge. And it is chopped when it strikes the rotor body. After that, the chopped wakes becomes the prolongation as it goes downstream. Also, the aerodynamic characteristics with the variation of the gap distance between a stator and rotor was investigated. Pressure jumps due to the passing wakes result in the pressure and lift loss and it gets stronger with the closer gap distance. This unsteady effect proves to be directly related to the fatigue and noise in turbomachinery and this study would be helpful to investigate such fields.

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An Experimental study on the anticonvulsive effects of Jinkyungondamtang (진경온담탕(鎭驚溫膽湯)의 항경련(抗痙攣) 작용(作用)에 관(關)한 실험적(實驗的) 연구(硏究))

  • Kim Woo-Yeoun;Kim Deog-Kon
    • The Journal of Pediatrics of Korean Medicine
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    • v.9 no.1
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    • pp.221-236
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    • 1995
  • In order to investigate the anticonvulsive effect of Jinkyungondamtang, the experiment were performed in mice. After solid exract of Jinkyungondamtang was orally administered to mice, four types of convulsion were induced in mice by electric shock, strychnine, picrotoxin, and caffeine. Each of the time to elicit the convulsion and to die was observed. Results were as follows: 1. In the case of convulsion induced by electric shock, the lapse of the time to elicit convulsion and the time to die were delayed by oral administration of Jinkyungondam-tang(P<0.05, P<0.025). 2. The solid extracts of Jinkyungondamtang were revealed rem- arkable effect in delaying the time to die induced by stry-chnine (P<0.05). 3. By oral administration of Jinkyungondamtang, the lapse of the time to elicit convulsion and to die were delayed significantly to elicit convulsion inducing by picrotoxin (P<0.05, P<0.05). 4. Considerable prolongation of the lapse of the time to elicit the convulsion was observed in convulsion induced caffeine due to the anticonvulsive effects of Jinkyungondamtang (P<0.05).

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