• Journal of Chest Surgery
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• 제16권3호
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• pp.272-280
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• 1983

With respect to controversial opinions concerning the nitroglycerin effects on cardiac muscle the direct nitroglycerin actions were thoroughly studied in isolated papillary muscles, atrial preparations and coronary strips of rabbits. Isometric active tension of papillary muscles developed at $35^{\circ}C$ upon electric stimulation at a rate of 60/min, was not affected by nitroglycerin up to a concentration of 10mg/L Higher concentrations of nitroglycerin, however, reduced action tension progressively. This depression of mechanical activity is accompanied by a decrease in oxygen consumption as measured by means of a flow respirometer. Resting oxygen uptake, on the other hand, remained unchanged. Similarly active tension of spontaneously beating atrial preparations also declined at a nitroglycerin concentration of more than 10 mg/L, whereas the sinus frequency did not change up to 40 mg/L. In contrast, rabbit coronary strips are much more sensitive to nitroglycerin and relax in a range of 10-100 ug/L of nitroglycerin concentration. The results indicate that the pharmacologic effects of nitroglycerin in coronary disease are due to vascular actions, because the plasma levels of nitroglycerin attainable in human therapy are not sufficiently high to directly influence the myocardium.

• Annals of Clinical Neurophysiology
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• 제3권2호
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• pp.168-171
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• 2001

It has been said that variable anatomical structures and neural circuits are related to the generation of tremor. There are cerebral cortex, thalamus, basal ganglia, inferior olivary nucleus, midbrain tegmentum, stretch reflex, and musculoskeletal structures. The stretch reflex is related with the physiologic tremor and various peripherally originated tremors. We experienced a case with the post-stroke resting tremor which was induced and aggravated by mechanical stretching stimulation. In the present case, stretch reflex has a major role in the generation and exacerbation of tremor. It is presumed that the development of tremor is attributed to the increased rhythmicity of ventral intermedius nucleus of thalamus. The enhancement of thalamic rhythmicity may be due to the increasement of long latency reflex by post-stroke rigidity. This case suggests that stretch reflex may have a major role in the pathophysiologic mechanisms of a certain centrally originated tremor.

• 한국의류산업학회지
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• 제24권6호
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• pp.812-824
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• 2022

This study proposes to develop a 3D printed re-entrant(RE) strip by shape memory thermoplastic polyurethane that can be deformed and recovered by thermal stimulation. The most suitable 3D printing infill density condition and temperature condition during shape recovery for mechanical behavior were confirmed. As the poisson's ratio indicated, the higher the recovery temperature, the closer the poisson's ratio to zero and the better the auxetic properties. After recovery testing for five minutes, it appeared that the shape recovery ratio was the highest at 70℃. The temperature range when the shape recovery ratio appeared to be more than 90% was a recovery temperature of more than 50℃ and 60℃ when deformed under a constant load of 100 gf and 300 gf, respectively. This indicated that further deformation occurred after maximum recovery when recovered at a temperature of 80℃, which is above the glass transition temperature range. As for REstrip by infill density, a shape recovery properties of 100% was superior than 50%. Additionally, as the re-entrant structure exhibited a shape recovery ratio of more than 90%, and exhibited auxetic properties. It was confirmed that the infill density condition of 100% and the temperature condition of 70℃ are suitable for REstrips for applying the actuator.

• 한국군사과학기술학회지
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• 제27권2호
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• pp.213-221
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• 2024

Aircraft's operational effectiveness is reduced due to threats from enemy anti-aircraft weapons, which is a weak point. In particular, guided missiles, which pose a threat to aircraft, are rapidly developing due to technological advancements in seekers, and are classified as one of the important technologies in weapon systems. Missile approach warning equipment installed to ensure aircraft survivability detects guided missiles and provides relevant information to respond. Tests were conducted domestically to verify the detection level of missile approach warning equipment, and test results were presented under various test conditions.

• 한국콘텐츠학회논문지
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• 제19권10호
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• pp.198-205
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• 2019

본 연구의 목적은 목 디스크 환자에게 기계적 자극을 적용하여 피부 감각의 변화를 유도하고 동일한 척수분절의 통증 역치와 근 긴장도 전-후 변화를 확인하고자 하였다. 이에 목 디스크 질환을 가지고 있는 남성 10명, 여성 20명으로 구성된 대상자를 총 30명 선정하고 실험을 진행하였다. 기계적 자극 그룹은 Graston 장비를 이용하여 5분간 피부 감각 변화를 유도하였고, 대조군은 아무런 조치를 받지 않았다. 피부 감각 변화는 Von Frey filament를 통해 검사를 진행하였고, 압통 역치의 변화는 압통 역치 측정기를 통해 측정하였고, 근 긴장도의 변화는 Myotone pro를 사용하여 측정하였다. 기계적 자극 적용 시 피부 감각의 역치는 통계적으로 유의하게 증가하였다(p<0.05). 동일한 척수 분절의 신경 지배를 받는 오른쪽 가시아래근의 압통 역치와 근 긴장도는 통계적으로 유의하게 증가하였고(p<0.05), 오른쪽 등세모근의 압통 역치는 통계적으로 유의하게 감소하였다(p<0.05). 하지만 다른 근육들의 압통 역치와 근 긴장도는 통계적으로 유의한 변화가 나타나지 않았다. 또한, 대조군에서는 피부 감각, 압통 역치, 근 긴장도의 변화가 통계적으로 유의하게 나타나지 않았다. 결과적으로 기계적 자극에 의해 유도된 피부 감각 변화는 동일 척수 분절의 압통 역치와 근 긴장도의 변화시켰다. 따라서 동일 척수 분절에 대한 기계적 자극의 적용을 통해 목 디스크 환자의 압통 역치, 근 긴장도의 증가와 통증 조절을 위한 새로운 재활 방법으로 임상적 의의가 있다고 판단된다.

• Journal of Pharmaceutical Investigation
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• 제36권3호
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• pp.185-192
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• 2006

The purpose of this study was to determine the effects of iontophoresis on transdermal delivery of procaine hydrochloride in healthy volunteers, as well as to the synergic effect of high voltage current or ultrasound on the efficacy of transdermal delivery of iontophoresis. Forty healthy volunteers were randomly assigned to four groups topical application group (TA), iontophoresis group (IT), pre-treatment of high voltage current stimulation with iontophoresis (HVS + IT), and pre-treatment of ultrasound application with iontophoresis (US + IT). All subjects received procaine iontophoresis on the forearm using direct current with 4 mA f3r 15 minutes. All subject was measured the duration of local anesthesia, pressure pain threshold, pain perception threshold using rectangular wave at 0.2 ms, 1 ms, 50 ms of rectangular current stimulation after procaine iontophoresis. For comparisons of the sensory characteristics and efficacy of iontophoresis between the groups, an one-way ANOVA and Kruskal-Wallis were used. The significant difference the duration of local anesthesia were found between the groups (p<0.001). The local anesthetic duration of IT, HVS+IT were significantly longer than TA. Meanwhile, the local anesthetic duration of US+IT was significantly longer than HVS+IT, IT and TA group (p<0.05). Also, the pressure pain threshold, pain perception threshold at 0.2 ms, 1 ms, 50 ms were significant difference between the groups (p<0.001). All sensory characteristics including pressure pain threshold, pain perception threshold of IT, HVS+IT was significantly increased than TA, whereas, US+1T was significantly increased HVS+1T, IT and TA (p<0.05). This study showed that the procaine iontophoresis have increase the duration of local anesthesia concomitantly pressure pain threshold and pain perception threshold of sensory nerve fibers such as $A-{\beta}$, $A-{\delta}$ and C fiber. This findings suggest that the iontophoresis enhanced the transdermal delivery of drug ions in vivo. The combination of ultrasound application and iontophoresis synergized the transdermal delivery of drug ions. It is suggests that an electric field, mechanical and heating property of ultrasound may contribute to synergic effect due to temporary changes of structure in the stratum corneum.

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 2003년도 제8차 학술대회 초록집
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• pp.103-105
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• 2003

After fifteen years of development, Magnetic Resonance (MR) technology for human imaging and spectroscopy is reaching a refined state with FDA approved 3T clinical products from Siemens, GE, and Philips. Broker has cleared CE approval with a 4T system. Varian supports a 4T system platform as well. Shielded magnets are standard at 3T from GE, Oxford, Magnex, and IGC. A shielded 4T whole body magnet is available from Oxford. Stronger switched gradients and dynamic shim coils, desired at any field, areespecially useful at higher static magnetic fields B0. In addition to the higher currents required for higher resolution slice or volume selection afforded by higher SNR, whole body gradient coils will be driven at increasing slew rates to meet the needs of new cardiac applications and other requirements. For example 3T and 4T systems are now being equipped with 2kV, 500A gradient coils and amplifiers capable of generating 4G/cm in 200msec, over a 67+/-cm bore diameter. High field EPI applications require oscillation rates at 1 kHz and higher. To achieve a benchmark 0.2 ppm shim over a 30cm sphere in a high field magnet, at least four stages of shimming need to be considered. 1) A good high field magnet will be built to a homogeneity spec. falling in the range of 100 to 150 ppm over this 30cm spherical "sweet spot" 2) Most modern high field magnets will also have superconducting shim coils capable of finding 1.5 ppm by their adjustment during system installation. 3) Passive ferro-magnetic shimming combined with 4) active, high order room temperature shim coils (as many as five orders are now being recommended) will accomplish 0.2 ppm over the 30cm sphere, and 0.1 ppm over a human brain in even the highest field magnets for human studies. Safety concerns for strong, fast gradients at any B0 field include acoustic noise and peripheral nerve stimulation. One or more of the mechanical decoupling methods may lead to quieter gradients. Patient positioning relative to asymmetric or short gradient coils may limit peripheral nerve stimulation at higher slew rates. Gradient designs combining a short coil for local speed and strength with a longer coil for coverage are being developed for 3T systems. Local gradients give another approach to maximizing performance over a limited region while keeping within the physiologically imposed dB0/dt performance limits.

• Journal of Periodontal and Implant Science
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• 제32권2호
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• pp.371-378
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• 2002

이번 연구에서는 19명 환자의 40개 상아질 지각과민 치아를 조사하였다. 지각과민증을 평가하기 위하여 기계, 온도 및 전기적 자극을 사용하였다. 상아질 지각과민증의 치료제로는 Gluma(R) Desensitizer (Heraeus Kulzer GmbH & Co., Germany)를 사용 하였다. 연구 방법은 다음과 같다: 지각과민증의 치료 전에 협면의 치관 $\frac{1}{3}$ 부위에서 전기치수검사를 시행하여 치수 생활력을 조사하였고, 그 측정치를 기록하였다. 그리고 기계 및 온도 자극을 이용한 검사를 시행하여 지각과민증의 유무를 확인하였다. 지각과민증이 존재함을 확인한 후에 지각과민증의 마모부에서 전기치수검사를 실시하였다. 치약을 전해질로 사용하였고 반응시의 숫자를 기록하였다. 이후 Gluma(R) Desensitizer를 이용하여 지각과민증을 치료하였다. 치료 후 마모 부위에서 기계, 온도 및 전기 검사를 다시 실시하고 그 결과를 기록하였다. 기계 및 온도 자극에 대해 40개 치아 모두에서 지각과민증 치료 전에는 반응을 보였으며 치료 후에는 반응을 보이지 않았다. 치관 $\frac{1}{3}$ 부위에서 전기치수검사를 실시하였을 때 모든 치아는 31에서 65 (48.9${\pm}$7.2)의 범위에서 반응하였다. 상아질 지각과민증의 치료 전에 전기치수검사를 실시하였을 때 34개의 치아는 2에서 반응하였고 나머지 6개의 치아는 17에서 25 범위에서 반응하였다. 치료 후에는 40개 치아 모두가 12에서 27 (19.6${\pm}$3.5)의 범위에서 반응하였다. 치료 전에 2보다 큰 숫자에서 반응을 보인 여섯개의 치아는 18에서 23의 범위에서 반응하였다. 이번 연구의 범위 내에서 다음과 같은 결론을 도출할 수 있다. 상아질 지각과민증을 보이는 치아가 기계 및 온도 자극에 반응을 보인다면 그 치아는 마모된 면에서 낮은 전기저항을 보인다. 반면 상아질 지각과민증을 치료하여 기계 및 온도 자극에 반응하지 않는다면 그 치아는 마모면에서 증가된 전기저항을 보인다. 전기치수검사는 상아질 지각과민의 진단에 활용될 수 있다. 나아가 전기치수검사는 상아질 지각과민증의 치료 결과를 평가하는 데 유용할 것이다. 하지만 전기치수검사는 상아질 지각과민을 측정하는 데에는 적절하지 못하다.

• Journal of Acupuncture Research
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• 제26권6호
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• pp.67-76
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• 2009

Objectives : The purpose of this study is to examine if Radix Aconiti herbal acupuncture may be effective to the neuropathic pain(mechanical allodynia, cold allodynia) in a rat model of neuropathic pain. Methods : To produce the model of neuropathic pain, under isoflurane 2.5% anesthesia, L5 spinal nerve was ligated by 6-0 silk thread. After neurophathic surgery, the author examined if the animals exhibited the behavioral sign of allodynia. The allodynia was assessed by stimulating the medial malleolus with von frey filament and acetone. Three days after the neuropathic surgery, Radix Aconiti herbal acupuncture was injected at Hwando($GB_{30}$) one time per two days for 2 weeks. After that, the author examined the withdrawal response of neuropathic rats' legs by von frey filament and acetone stimulation. And also the author examined c-Fos in the midbrain central gray of neuropathic rats and the change of WBC, RBC, HGB, HCT count in the blood of neuropathic rats. Results : The Radix Aconiti herbal acupuncture injected Hwando($GB_{30}$) decreased the withdrawal response of mechanical allodynia that assessed with von frey filament in RA1-$GB_{30}$, RA2-$GB_{30}$ group as compared with control group. The Radix Aconiti herbal acupuncture injected Hwando($GB_{30}$) decreased the withdrawal response of chemical allodynia(cold allodynia) that assessed with acetone in RA1-$GB_{30}$, RA2-$GB_{30}$ group as compared with control group. The Radix Aconiti herbal acupuncture injected Hwando($GB_{30}$) showed the significant between control group and RA2-$GB_{30}$ group in the c-Fos expression. The Radix Aconiti herbal acupuncture injected Hwando($GB_{30}$) did not show the significant between control group and RA1-$GB_{30}$ group, RA2-$GB_{30}$ group and RA3-$GB_{30}$ group in the WBC, RBC, HGB, HCT count. Conclusions : We have noticed that Radix Aconiti herbal acupuncture at Hwando($GB_{30}$) decreased mechanical allodynia and cold allodynia in the model of neuropathic pain compared with the control group. C-fos expression in the central gray of that group was also decreased compared with the control group. This study can be used as a basic resource on a study and a treatment of pain.

• Journal of Acupuncture Research
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• 제22권5호
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• pp.67-77
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• 2005

Objectives : The purpose of this study is to examine if Bee Venom Acupuncture may be effective to the neuropathic pain(mechanical allodynia, cold allodynia) in a rat model of neuropathic pain. Methods : To produce the model of neuropathic pain, under isoflurane 2.5% anesthesia, tibial nerve and sural nerve was resected. After the neuropathic surgery, the author examined if the animals exhibited the behavioral signs of alloynia. The allodynia was assessed by stimulating the medial malleolus with von Frey filament and acetone. Three weeks after the neuropathic surgery, Bee Venom Acupuncture was injected at Hwando(GB30) one time a day for one week. After that, the author examined the withdrawl response of neuropathic rats' legs by yon Frey filament and acetone stimulation. And also the author examined c-Fos in the midbrain central gray of neuropathic rats and the change of WBC count in the blood of neuropathic rats. Results : The Bee Venom Acupuncture injected Hwando(GB30) decreased the withdrawl response of mechanical allodynia in BV-2, BV-3 group as compared with control group. The Bee Venom Acupuncture injected Hwando(GB30) decreased the withdrawl response of chemical allodynia(cold allodynia) in BV-2, BV-3 group as compared with control group. The Bee Venom Acupuncture injected Hwando(GB30) showed the significant difference between control group and BV-2 group, control group and BV-3 group in the c-Fos expression and U count. Conclusion : We have noticed that Bee Venom Acupuncture at Hwando(GB30) decreased mechanical allodynia and cold allodynia in the model of neuropathic pain compared with the control group. C-Fos expression in the central gray of that group was also decreased compared with the control group. Psin control using Bee Venom Acupuncture was accumulated as time goes by. This study can be used as a basic resource on a study and a treatment of pain.