• Title/Summary/Keyword: pressure injection

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Pine Needle Extracts Inhibit Contractile Responses of the Isolated Rat Aortic Strips

  • Cheong, Hyeon-Sook;Lim, Dong-Yoon
    • Natural Product Sciences
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    • v.16 no.2
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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.

General Pharmacological Properties of Recombinant Human Parathyroid Hormone (재조합 부갑상선 흘몬의 일반약리작용)

  • 이은방;장혜옥;이향주;천선아
    • Biomolecules & Therapeutics
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    • v.6 no.2
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    • pp.159-164
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    • 1998
  • General pharmacological properties of recombinant human parathyroid hormone (hPTH) were examined. The administration of hPTH (7, 35 and 175 lU/kg sc) in mice had no effects in general behavior and central nervous system, and no influences on normal body temperature, writhing syndromes induced by 0.7% acetic acid solution and chemoshock produced by strychnine and pentetrazol solution. hPTH (9 and 44 lU/kg, sc) given to anesthetized rabbits showed no effect on blood pressure of carotid artery and respiration, and it did not influence the responses produced by injection of acetylcholine or epinephrine. It showed no direct effect at 4.4$\times$10$_{-2}$IU/ml in isolated stomach fundus and uterus of rats and ileum of guinea-pig, and it also showed no inhibition of contraction produced by acetylcholine, oxytocin, serotonin and histamine in the above-mentioned preparations. It did not influence intestinal propulsion at the doses of 7,35 and 175 lU/kg sc in mice. This drug exhibited no effect on urinary excretion at the doses of 7 and 35 lU/kg sc in rats. However, at a dose of 175 lU/kg sc, it showed a decreased urination along with decreased excretion of potassium, sodium and chloride ion. These results indicate that hPTH does not exert any of serious pharmacological effects except the inhibition of urination at a highest dose used.

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General Pharmacology of Recombinant Erythropoietin (LB-00014) (유전자 재조합 Erythropoietin (LB-00014)의 일반약리작용)

  • 이은방;이향주;천선아;조성익;손지영
    • Biomolecules & Therapeutics
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    • v.4 no.2
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    • pp.154-161
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    • 1996
  • General pharmacological properties of LB-00014, an erythropoietin which was produced by recombinant DNA technique in Biotech Research Institute, LG Chemical Ltd. were examined. The administration of LB-00014 (60, 600, 6000 IU/kg, iv) in mice had no effect in general behavior and central nervous system, and no influences on normal body temperature, writhing syndromes induced by 0.7% acetic acid solution and chemoshock produced by strychnine and pentetrazole solution. LB-00014 (60, 600, 6000 IU/kg, iv) given to anesthetized rabbits showed no effect on blood pressure of carotid artery and respiration rates, and it did not influence the responses produced by injection of acetylcholine or epinephme. The administration of LB-00014 (601, 600, 6000 IU/kg, iv) in rats had no effect on the plasma prothrombin time, activated partial thromboplastin time and hemolytic action. The platelet aggregation induced by collagen in human plasma was not influenced by LB-00014 (10, 100, 1000 lU/kg, iv). It showed no direct effect at 100 and 1000IU/m1 in isolated stomach fundus and uterus of rats and ileum of guinea-pig, and it also had no inhibition of contraction produced by acetylcholine, oxytocin, serotonin and histamine in the above-mentioned preparations. It did not influence gastric secretion, pH and acid output at 6000 IU/kg, iv in rats, but showed a significant increase in intestinal propulsion of mice at 6000 IU/kg, iv. Its administration (60, 600, 6000 lU/kg, iv) caused no effect on urine and electrolyte excretion in rats. These results indicate that LB-00014 does not exsert any of serious pharmacological effects.

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An Optimum Design of Replication Process to Improve Birefringence, Radial-Tilt and Land-Groove Structure in DVD-RAM Substrates (DVD-RAM 기판의 복굴절, Radial-Tilt 및 전사성 향상을 위한 사출압축성형공정 최적화)

  • Gang, Sin-Il;Seong, Gi-Byeong;Lee, Nam-Seok
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.4
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    • pp.637-643
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    • 2002
  • The objective of this study is to provide a simple methodology to find optimum processing conditions to fabricate sub-micron structured DVD-RAM substrates with superb optical and geometrical properties. It was fecund that the birefringence, which is regarded as one of the most important optical properties for an optical disk, was very sensitive to the mold wall temperature history. Also, the integrity of the replication, represented by the land-groove structure and the radial tilt were influenced by the mold temperature and the compression pressure. A set of optimum conditions were obtained by applying Design of Experiment and the objective functions composed of three different objectives.

The Effect of Velocity Control Method on the Part Characteristic in Semi-Solid Die Casting (반용융 다이캐스팅 공정에 있어서 속도제어방법이 제품의 특성에 미치는 영향)

  • Seo, Pan-Ki;Kang, Chung-Gil;Son, Young-Ik
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.10
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    • pp.2034-2043
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    • 2002
  • The process design to produce a near net shape home-appliance compressor component using semi-solid die casting process is performed. In order to obtain a good component without defects such as liquid segregation and porosity, the relationship between pressure and time, and plunger tip displacement and injection velocity are proposed with repeated trial and error. The effect of the velocity variation in the process parameters on liquid segregation and extraction is investigated to produce the aluminum frame part(a kind of compressor part) with good mechanical properties. The mechanical characteristic of semi-solid die casting formed parts for AlSi7Mg0.65r(A357) and AlSi17Cu4Mg(A390) are investigated with a view to minimizing the occurrence of defects. To investigate of application possibility at industry field, A380 aluminum alloy with 8∼9% silicon contents used for the squeeze casting process. The obtained mechanical properties is compared with semi-solid die casting.

The Interaction for the pit formation on ABS with laser beam (레이저에 의한 ABS의 홈 형성에 동반되는 상호작용)

  • Kim Youngseop;Park Sohee;Shin Yongjin
    • Proceedings of the Korean Society of Laser Processing Conference
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    • 2004.10a
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    • pp.22-28
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    • 2004
  • Pit and rim formation on the Acrylonitrile Butadiene Styrene(ABS) plastic surface was evaluated after it was irradiated by $CO_2$ and Nd:YAG laser beams. Our results show that thermal effect floor was well observed at the outer wall of pit with $CO_2$ laser irradiated while it was not the case with Nd:YAG laser irradiated. Also the volume and depth of pit formation increase proportionally with the energy intensities of two laser irradiations, but there are significant differences in the slope, width, and FWHM of the Pit formation with two types of laser irradiations. This result shows that $CO_2$ laser irradiation leads to better cooling contraction effect while Nd:YAG laser irradiation induces better recoil pressure effect during the interaction between ABS plastic and laser beam irradiation. The shape of the laser marking could vary significantly depending on the traveling path of molten plastic during injection molding of ABS plastic. Therefore, the selection of material and molding process can have a great impact on the performance of optical storage media.

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Study on the Silicon Pump and Control System for TFT-LCD Manufacturing Process (TFT-LCD 생산공정을 위한 실리콘 펌프 및 제어시스템에 관한 연구)

  • Park, Hyoung-Keun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.8
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    • pp.3618-3622
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    • 2012
  • In this study, the yield of the modules in LCD production lines, improving current TFT-LCD production process is essential for high-pressure silicone injection equipment, and precision control system was developed. This full-scale production of the future through the development of next-generation display production line is being prepared, being transferred to China in LCD production facilities can make the most of efficient equipment. Therefore, minimize the cost of new investment and help create the maximum effect to control the detailed behavior of the sequence H/W and S/W system was installed on the production line. In addition, Fast-evacuating the structure proposed for the Vacuum pump, Pump control circuit design and experimental results has been completed.

Experimental Study for Removing Artificial Patinas of Bronze Sculpture by Nd:YAG Laser Cleaning System (청동 조형물의 인공 파티나 제거를 위한 Nd:YAG 레이저 적용 실험 연구)

  • Park, Chang-Su;Cho, Nam-Chul
    • Journal of the Korean institute of surface engineering
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    • v.46 no.5
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    • pp.197-207
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    • 2013
  • In the midst of increasing importance of modern cultural assets, especially, most modern bronze objects are exposed to outdoor environment, and as the objects are corroded steadily due to environmental factors the objects lost their original colors on the surface. We performed artificial patinas on the bronze sample per each color of red, black and green and checked cuprite and tenorite which are detected from actual bronze corrosion by analyzing the components. In addition, we applied the existing corrosion removal methods of grinder and sand blaster on a similar sample of bronze mirror per injection pressure and performed comparative analysis on the result with Nd:YAG laser. As a result of Nd:YAG laser cleaning artificial patina from bronze samples, all of the patinas were removed by laser wavelength 1064 nm better than 532 nm. Upon applying to a similar sample of bronze mirror, the artificial patina could be selectively removed from substrates without surface damage when Nd:YAG laser was conducted other than the existing removal method, and so it showed the possibility of application.

Effects of Fuel-Injection Pressure on the Spray Breakup Characteristics in Small LRE Injector (소형 액체로켓엔진 인젝터의 분무 분열특성에 대한 연료분사압력의 영향)

  • Jung, Hun;Kim, Sung-Cho;Park, Jeong;Kim, Jeong-Soo
    • Journal of the Korean Society of Propulsion Engineers
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    • v.11 no.3
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    • pp.50-57
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    • 2007
  • Spray characteristics of an injector in a small liquid rocket engine (LRE) is characterized by Particle Image Velocimetry (PIV) and Dual-mode Phase Doppler Anemometry (DPDA). Instantaneous plane images captured by PIV are examined for the qualitative prediction of spray breakup with the setup of evaluation technique for effect of spray angles on injector performance. DPDA is also applied in order to quantify the average velocity, turbulent intensity, SMD, and number density of spray droplets along the spray stream distance leading to precise observation of spray atomization behavior. An objective of the study is the derivation of design parameters of new injectors and the establishment of performance criteria through the clear understanding of spray characteristics.

Disintegration and Spreading Behavior of the Spray emanating from a Liquid-thruster Injector (액체추력기 인젝터로부터 발생하는 분무의 분열 및 확산 거동)

  • Kim, Jin-Seok;Jung, Hun;Kim, Jeong-Soo;Kim, Sung-Cho;Park, Jeong
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2008.11a
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    • pp.113-116
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    • 2008
  • Pseudo-3D Spatial distribution of spray droplets is investigated by using Dual-mode Phase Doppler Anemometry (DPDA) in order to examine the disintegration and spreading behavior of spray exiting from liquid-thruster injector. Spray injected from nozzle orifice with length-to-diameter ratio $(L/d_o)$ of 1.67 and at the injection pressure of 27.6 bar is aligned to the vertical. Vertical and horizontal mean velocities of droplets, Arithmetic Mean Diameter (AMD), Sauter Mean Diameter (SMD), and volumetric flux decrease as droplets travel from center/upstream toward outer region/downstream of spray.

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