• 한국의류산업학회지
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• 제2권5호
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• pp.405-410
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• 2000

The effects of individual sweating rates on thermophysiological responses during the decrease phase of clothing surface temperature (Tcs) with cotton (C) and polyester (P) clothed subjects were examined. Seven women subjects were exposed in a climatic chamber at ambient temperature of $27.2^{\circ}C$, relative humidity of 50%, and their lower-legs were immersed in a water bath at a temperature of $35-41^{\circ}C$ for 70 min. During water immersion, Tcs in C-clothed subject rose immediately after the onset of sweating and then Tcs fell gradually. In C-clothed subjects, Tcs decreased directly (p<0.05) in proportion to total sweating rate (TSR), however no significant correlation was observed in P-clothed subjects. The relationship between TSR and changes in mean skin temperature, and skin blood flow showed negative correlation when wearing C-clothing (p<0.05), however, no significant correlation when wearing P-clothing. Individual TSR was correlated with threshold rectal temperature for sweating onset (p<0.05) with C- and P-clothed subjects. The results showed that individual TSR had significant effects on not only Tcs but also on thermoregulatory responses during the Tcs decrease phase.

• Archives of Reconstructive Microsurgery
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• 제8권2호
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• pp.170-175
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• 1999

Objective : Extracranial-intracranial(EC-IC) microvascular anastomosis was performed in 18 patients with hemodynamic cerebral ischemia and traumatic cerebral aneurysm, the aim of this retrospective study was to assess its value in neurosurgical field. Method : Of 18 cases, 17 case were hemodynamic cerebral ischemia and one was traumatic cerebral aneurysm. There were 14 superficial temporal artery(STA)-to-middle cerebral artery(MCA) anastomosis, 3 saphenous vein graft bypass(2 external carotid artery(ECA)-to-MCA, 1main trunk of the STA-to-MCA) and 1 radial artery bypass(ECA-to-MCA). Results : Bypass patency was confirmed by postoperative angiography in all cases except for two cases, postoperative cerebral blood flow of ischemic brain showed significant increased in all cases with good patency through bypass. Conclusion : Revascularization by EC-IC microvascular anastomosis to the ischemic brain eliminated ischemia and was associated with excellent good outcome and good patency rates.

• 대한한의학회지
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• 제26권1호
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• pp.115-122
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• 2005

Background and objective: Gastrodiae Rhizoma (GR), the rhizoma of Gastrodia elata BL., is one of the popular drugs to treat headache, dizziness, blackout, numbness of limbs, hemiplegia, facial paralysis, dysphrasia, and infantile convulsions. It has been reported that it provides an antihypertensive effect and lowers cerebrovascular resistance in animal experiments. However, there has been no data about these effects with human subjects. In this study, the author examined the effect of Gastrodiae water extracts on blood pressure and cerebrovascular reactivity in human subjects. Methods: We selected 16 normal volunteers, who were divided into 2 groups: Gastrodiae extract administration group and placebo (creamy powder) group. Using transcranial Doppler ultrasound, we monitored changes of mean flow velocity and breath-holding induced CO2 reactivity of middle cerebral artery in both groups. Mean blood pressure, heart rate and PETCO2 were measured using Compact Anesthesia Monitor. In both groups, all evaluation was performed during basal condition, and repeated at 30, 60, and 90 min after administration. Results: Gastrodiae extract decreased CO2 reactivity after administration, reaching the lowest level at 90 minutes $(-29.1\%\;vs.\;basal\;level)$, which showed significant difference compared with the placebo group (p = 0.004). In the placebo group, the pulse rates tended to decrease over time (at 90 minute, $-5.2\%$ vs. basal level) while in the Gastrodiae group the values showed nearly no change, which showed significant difference between both groups (p = 0.036). However, the changes of mean blood pressure and mean flow velocity did not show significant difference between both groups. Conclusion : This study demonstrated that Gastrodiae extract significantly decreased breath-holding induced CO2 reactivity. This result suggests that the clinical effect of Gastrodiae extract might be caused by increasing cerebral blood flow via dilation of cerebral resistant vessels instead of antihypertensive effect.

• 약학회지
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• 제48권6호
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• pp.317-322
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• 2004

The use of nonsteroidal anti-inflammatory drugs (NSAIDs) is limited by their ability to induce gastrointestinal injury. It has been shown that nitric oxide (NO), similar to pro staglandins (PGs), appears to play an important role in gastric mucosal defence. We hypothesized that NSAIDs contained NO group would be less acutely toxic to the gastric mucosa, but would not interfere with their ability to suppress inflammatory process in rats. We have compared the ulcerogenic and anti-inflammatory effect of CW-501029 (NO-NSAIDs), CW-501027 (NSAIDs) and indomethacin. Both did not change mean blood pressure and heart rates, indicating that they had no side effect on cardiovascular system. We found that CW-501029 increased nitrite/nitrate levels without changing of blood pressure and heart rates. We suggest that it may help gastric mucosal blood flow, the which helps reducing the discomfort in astrointestinal system. Carrageenan-induced PGE2 increase was reduced in a similar tendency when compared CW-501027 or CW-501027 with control in back exudate of rats, but CW-501029 less reduced PGE2 than CW-502027 or indomethacin in gastric tissues. CW-501027 or CW-501029 reduced platelet aggregation. From these results we suggest that CW-501029 may improve the side effect by reduction of short-term gastric injury and less inhibition of PGs synthesis.

• Journal of Chest Surgery
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• 제38권10호
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• pp.661-668
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• 2005

배경: 체외순환장치 중 막형산화기를 사용하는 인공심폐기나 생명구조장치(Extra-corporeal Life Support System; ECLS)는 혈액이 통과하기 위해 막형산화기 전방에 구동점프가 요구된다. 국내에서 개발된 박동식 생명구조장치(T-PLS)의 경우는 막형산화기가 두 개의 혈액주머니 사이에 위치하여 액츄에이터가 번갈아 까내는 구조로 되어 있다 저자 등은, 만일 저항이 낮은 gravity-flow hollow fiber 막형산화기를 사용한다면 두 개의 혈액주머니와 박동점프를 막형산화기 후방에 설치하는 것이 가능하며, 이러한 구조는 같은 펌프박동 조건에서 2배의 맥박수를 보장하므로 펌프박출량이 증가될 것으로 가정하였다. 본 실험은 한국형 생명구조장치의 회로구성을 최적화하기 위해 계획되었으며, 기존의 막형산화기를 사용한 직렬회로구조와 gravity-flow hollow fiber 막형산화기를 이용한 병렬회로 구조를 박동에너지와 펌프박출량을 이용하여 비교하였다. 대상 및 방법: 실험은 $35\~45kg$의 돼지 12마리에서 심실세동혈 심정지 모델을 만들었으며, T-PLS 회로구성 형태에 따라 두 군으로 나누었다. 직렬군은 두 개의 혈액주머니 중간에 기존 막형산화기를 직렬로 설치하였으며, 병렬군은 gravity-flow hollow fiber막형산화기 후방에 이중구동점프를 병렬로 설치하였다. 펌프박출량은 대동맥 도관에서 직접 혈류를 측정하였고, 등가압력에너지(EEP)는 실시간으로 컴퓨터에 저장된 펌프박출곡선과 하행대동맥 혈압곡선에서 계산하였다. 각 지표는 점프속도 30, 40, 50 BPM에서 매번 측정하였다. 결과: 두 군 모두 박동에너지 측면에서 충분한 박동성을 보여주었다. 점프속도 30, 40, 50 BPM에서 EEP와 평균동맥압의 변화율은 병렬군의 경우 $13.0\pm.7\%,\;12.0\pm1.9\%,\;and\;7.6\pm0.9\%$였으며, 직렬군의 경우 $22.5\pm2.4\%,\;23.2\pm1.9\%,\;and\;21.8\pm1.4\%$였다. 점프박출량의 경우는 점프속도 40, 50 BPM에서 병렬군의 경우 $3.1\pm0.2\;and\;3.7\pm0.2L/min$였으며, 직렬군의 경우 $2.2\pm0.1\;and\;2.5\pm0.1\;L/min$였다(p<0.05). 결론: 혈류 저항이 낮은 gravity-flow 막형산화기를 사용하여 T-PLS 구동점프를 병렬회로로 배치할 경우 효과적인 박동성은 유지하면서, 기존의 막형산화기를 이용한 직렬회로 구조에 비해 점프박출량을 증가시켰다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.165-170
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• 2004

The purpose of this work was to assess and quantify the beneficial effects of long-term gas exchange, at varying frequencies, for the development of a vibrating intravascular lung assistance device (VIVLAD), for patients suffering from acute respiratory distress syndrome (ARDS). The experimental design and procedure have been applied to the construction of a new device for assessing the effectiveness of membrane vibrations. An analytical solution has been developed for the hydrodynamics of flow through a bundle of sinusoidally vibrated hollow fibers, with the intention of gaining insight into how wall vibrations might enhance the performance of the VIVLAD. As a result, the maximum oxygen transfer rate was reached at the maximum amplitude and through the transfer of vibrations to the hollow fiber membranes. The device was excited by a frequency band of 7Hz at various water flow rates, as this frequency was the 2nd mode resonance frequency of the flexible beam. 675 hollow fiber membranes were also bundled, within the blood flow, into the device.

• Journal of Chest Surgery
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• 제19권1호
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• pp.18-24
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• 1986

The mean perfusion pressure produced by 20 different design and size of disposable aortic perfusion cannulas [size range: 18F to 20F] at flow rates of 1 to 5 L/min was compared. A roller pump with perfusion tubing 10mm in inner diameter was used with a mixture of 0.9% normal saline and 100% glycerin [mixing ratio of 6.72:13.28] to make the viscosity as normal blood in 20oC as the test solution. Line pressure in these cannulas at a flow rate of 3L/min ranged from 13.2$\pm$4.47 to 157$\pm$1 34 mmHg in a case of absence of resistance, and from 11.4$\pm$1.14 to 227.2$\pm$4.47 mmHg in a case of presence of resistances 14 cannulas had gradients of less than 100Hg at a flow rate of 3L/min and 9 cannulas less than 100mmHg at 4L/min. The following results were obtained from this experimental study: .1] A wide range of line pressure was observed in disposable aortic perfusion cannulas currently in clinical use; 2] Some cannulas currently used for cardiopulmonary bypass in adults generated excessive line pressure; 3] Both the material and design affect function, with some designs safer than others. Cardiac surgeons should base the choice of aortic perfusion cannula on the best performance and safest design available to avoid cannula-related problems during operation.

• Archives of Plastic Surgery
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• 제35권4호
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• pp.360-366
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• 2008

Purpose: Botulinum toxin type A(BoTA) can block the release of vasoconstriction cotransmitters as well as acetylcholine in nerve terminal. The authors observed that BoTA increases flap survival by preventing sympathetic collapse of peripheral vessels. Methods: 10 Sprague Dawley rats were divided into control(n=5), and BoTA group(n=5). $3{\times}10cm$ sized random pattern cutaneous flaps were elevated on the dorsal side in both groups. In BoTA group, BoTA was injected into the flap via intradermal to subdermal route, 7 days before the flap elevation. Flap survival rates (survival area/total area) were measured 7 days after the elevation. Cutaneous blood flow was measured in proximal, middle and distal compartments of the flap using laser Doppler flowmetry initially, preoperatively, at immediate postoperation, and 7 days after flap elevation, respectively. Histological examination was performed 7 days after the flap elevation. The number and shape of the vessels were evaluated under microscope. Results: Mean flap survival was $53.18{\pm}6.58%$ in control group and $93.79{\pm}6.06%$ in BoTA group, displaying statistically significant difference(p=0.0008, p<0.05). In the control group, blood flow to the middle and distal compartments of the flap decreased significantly immediately after flap elevation. In the BoTA group, blood flow to the middle compartment did not decrease(p=0.002) and slightly decreased in the distal compartment(p=0.001). Cutaneous blood flow was significantly higher in all compartments of the flap in BoTA group than in control group, 7 days after the flap elevation. In histopathologic examination, greater number of vessels were noted in the BoTA group than in the control group. Conclusion: Botulinum toxin A can increase the survival of the random pattern cutaneous flap in rats by preventing the sympathetic collapse of peripheral vessels.

• 대한의용생체공학회:의공학회지
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• 제24권2호
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• pp.121-126
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• 2003

본 연구는 진동형 장치의 활용을 통해 혈관 내 폐 보조장치의 기체전달 효율을 향상시키고자 시도하였으며, 진동에 따른 혈액의 용혈 문제에 있어서 한계 용혈이 발생하는 영역을 선정하고자 하였다. 가진 주파수가 0 Hz일 때를 기준으로 하여 중공사 수의 변화에 따라 산소전달속도를 측정하였다. 최대의 산소전달속도를 나타내는 중공사 모듈에서 가진 주파수의 변화에 따른 산소전달속도를 측정하고 혈액의 용혈도를 측정하였다. 측정결과 액체 유속의 변화에 따라 최대 산소전달속도를 나타내는 중공사 모듈은 type 6으로 이때의 중공사 개수는 675개이다. 또한, 중공사를 가진하지 않았을 때 최대의 산소전달속도를 보여주는 모듈은 type 6이었다. 모듈 type 6의 가진 주파수의 변화에 따른 산소전달속도는 7 Hz에서 최대산소전달속도를 나타내었으며 최대산소전달속도를 나타내는 7 Hz의 가진 주파수에서의 혈액 용혈도를 측정한 결과 혈액의 용혈도는 낮았다. 그러므로 최대 흔들림이 일어나는 7 Hz를 한계 용혈 주파수로 결정할 수 있었다.

• Journal of Trauma and Injury
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• 제27권2호
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• pp.20-24
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• 2014

Purpose: The temperature of a warm fluid infused into a patient is lowered because the line that allows the fluid to be infused into the patient is exposed to room air. This study evaluated the effects of aluminum foil used as an insulator surrounding the fluid infusion lines when using warm crystalloid fluids to treat traumatic shock patients. Methods: The study measured the differences in fluid temperature between infusion lines with and without the aluminum-foil insulation. We used 1L of normal saline at $40^{\circ}C$ as the infusion fluid, and the fluid infusion line was 200 cm long. The differences in temperature were measured for various fluid flow rates from 12,000 mL/min to 100 mL/min. We performed three experiments at each flow rate. Results: The results showed the differences in temperature between the groups with and without the aluminum insulation were significant for flow rates above 100 mL/min. Conclusion: Hypothermia in trauma patients results in many adverse complications such as peripheral vascular constriction, tissue hypoxia, metabolic acidosis, heart dysfunction and so on. Thus, the use of warm fluids and blood components is essential to reduce the probability of hypothermia. This study showed the aluminum foil wrapped around the infusion line had an insulator effect. As a result, such a wrapping can be used to avoid the adverse effects of hypothermia.