• 대한의용생체공학회:의공학회지
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• 제6권2호
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• pp.1-8
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• 1985

The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70$\pm$1.32mmHg/min)compared to CF dialyzers(4.32$\pm$0.55mmHg/min)(p<0.05). However, there was no observable difference in the UFR between the two dialyzers. Neither APD nor UFR showed any significant increase with an increasing number of reuses for up to more than 20reuses. A substantial number of failures observed in APD(larger than 20mmHe/min)on the reused dialyzers(2 out of 40 CP and S out 26 C-DAK) were attributed to the Possible damage on the fibers. The CF 15-11 HFDs which failed APD test did not show changes in the UFR compared to normal dialyzers indicating that APD is a more sensitive test than UFR test to evaluate the integrity of the fibers. 30527 T00401030527 ^x For quantitative measurement of reflected light from a clinical diagnostic strip, a prototype old reflectance photometer was designed. The strip loader and cassette were made to obtain more accurate reflectance parameters. The strip was illuminated at 45˚c through optical fiber and the intensity of reflected light was determined at rectanguLat angle using a photodiode. The kubelka-munk coefficient and reflection optical density were determined ar four different wavelengths(500, 550, 570 and 610nm) for blood glucose strip. For higher concentration than 300mg/41 about glucose, a saturation state of abforbance was observed at 500, 550 and 570nm. The correlation between glucose concentration and parameters was the best at 610nm. 30535 T00401030535 ^x Radiation-induced fibrosarcoma tumors were grown on the flanks of C3H mice. The mice were divided into two groups. One group was injected with Photofrin II, intravenously (2.5mg/kg body weight). The other group received no Photofrin II. Mice from both groups were irradialed for approximately 15 minutes at 100, 300, or 500 mW/cm2 with the argon (488nm/514.5 nm), dye(628nm) and gold vapor (pulsed 628 nm) laser light. A photosensitizer behaved as an added absorber. Under our experimental conditions, the presence of Photolfrin II increased surface temperature by at least 40% and the temperature rise due to 300 mW/cm2 irradiation exceeded values for hyperthermia. Light and temperature distributions with depth were estimated by a computer model. The model demonstrated the influence of wavelength on the thermal process and proved to be a valuable tool to investigate internal temperature rise. 30536 T00401030536 ^x We investigated the structural geometry of thirty-eight Korean femurs. The purpose of this study is to identify major geometrical differences between Korean femurs 3nd others that we believe belong to Caucasians so that we would be able to get insights into the femoral component design that fits Asians including Koreans. We utilized computerized tomography (CT) images of femurs extracted from cadavers. The CT images were transformed into bitmap data by using a film scanner, and then analyzed by using a commercially available software called Image v.1.0 and a Macintosh IIci computer.The resulting data were compared with already published data. The major results show that the geometry of the Korean femurs is significantly different from that of Caucasians: (1) the anteversion angle and the canal flare index are greater by the amount of approximately 8˚ and 0.5, respectively, (2) the shape of the isthmus cross section is more round, and (3) the distance between the teaser trochanter and the proximal border of the isthmus is shelter by about 15 mm. The results suggested that the femoral component suitable for Asians should be different from the currently-used components designed and manufactured mostly by European or American companies. 30537 T00401030537 ^x It is well known that nonlinear propagation characteristics of the wave in the tissue may give very useful information for the medical diagnoisis. In this paper, a new method to detect nonlinear propagation characteristics of the internal vibration in the tissue for the low frequency mechanical vibration by using bispectral analysis is proposed. In the method, low frequency vibration of f0( = 100Hz) is applied on the surface of the object, and the waveform of the internal vibration x (t) is measured from Doppler frequency modulation of silmultaneously transmitted probing ultrasonic waves. Then, the bispectra of the signal x (t) at the frequencies (f0, f0) and (f0, 2f0) are calculated to estimate the nonlinear propagation characteristics as their magnitude ratio, w here since bispectrum is free from the gaussian additive noise we can get the value with high S/N. Basic experimental system is constructed by using 3.0 MHz probing ultrasonic waves and the several experiments are carried out for some phantoms. Results show the superiority of the proposed method to the conventional method using power spectrum and also its usefulness for the tissue characterization. 30541 T00401030541 ^x This paper describes the implementation of a computerized radial pulse diagnosis by aids of a clinical expert. On this base, we composed of the radial pulse diagnosis system in korean traditional medicine. The system composed of a radial pulse wave detection system and a radial pulse diagnosis system. With a detection system, we detected Inyoung and Cheongu radial pulse wave and processed it. Then, we have got the characteristic parameters of radial pulse wave and also quantified that according to the method of Inyoung-Cheongu Comparison Radial Pulse Diagnosis. We defined the jugement standard of radial pulse diagnosis system and then we confirmed the possibility for realization of automatic radial pulse diagnosis in korean traditional medicine. 30545 T00401030545 ^x Microspheres are expected to be applied to biomedical areas such as solid-phase immunoassays, drug delivery systems, immunomagnetic cell separation. To synthesize microspheres for biomedical application, "two stage shot growth method" was developed. The uniformity ratio of synthesized microspheres was always smaller than 1.05. And the surface charge density (or the number of ionizable functional groups) of the microspheres synthesized by "two stage shot growth method" was 6~13 times higher than that of the microspheres synthesized by conventional seeded batch copolymerization. As a previous step for biomedical application, adsorption experiments of bovine albumin on microspheres were carried out under various conditions. The maximum adsorbed amount was obtained in the neighborhood of pH 4.5. Isoelectric point of bovine albumin is pH 5.0, so experimental result shows that it shifted to acid area. The adsorption isotherm was obtained, the plateau region was always reached at 2.Og/L (bulk concentration of bovine albumin).The effect of the kind and the amount of surface functional group was also examined. 30575 T00401030575 ^x A medical image workstation was developed using multimedia technique. The system based on PC-486DX was designed to acquire medical images produced by medical imaging instruments and related audio information, that is, doctors' reporting results. Input information was processed and analyzed, then the results were presented in the form of graph and animation. All the informations of the system were hierarchically related with the image as the apex. Processing and analysis algorithms were implemented so that the diagnostic accuracy could be improved. The diagnosed information can be transferred for patient diagnosis through LAN(local area network). 30592 T00401030592 ^x In the conventional infrared imaging system, complex infrared lens systems are usually used for directing collimated narrow infrared beams into the high speed 2-dimensional optic scanner. In this paper, a simple reflective infrared optic system with a 2-dimensional optic scanner is proposed for the realization of medical infrared thermography system. It has been experimentally proven that the intfrared thermography system composed of the proposed optic system has the temperature resolution of 0.1˚c under the spatial resolution of lmrad, the image matrix size of 256 X 240, and tile imaging time of 4 seconds. 30593 T00401030593 ^x In this paper, MIIS (Medical Image Information System) has been designed and implemented using INGRES RDBMS, which is based on a client/server architecture. The implemented system allows users to register and retrieve patient information, medical images and diagnostic reports. It also provides the function to display these information on workstation windows simultaneously by using the designed menu-driven graphic user interface. The medical image compression/decompression techniques are implemented and integrated into the medical image database system for the efficient data storage and the fast access through the network. 30594 T00401030594 ^x In this paper, computerized BEAM was implemented for the space domain analysis of EEG. Trans-formation from temporal summation to two-dimensional mappings is formed by 4 nearest point inter-polaton method. Methods of representation of BEAM are two. One is dot density method which classify brain electrical potential 9 levels by dot density of gray levels and the other is colour method which classify brain electrical 12 levels by red-green colours. In this BEAM, instantaneous change and average energy distribution over any arbitrary time interval of brain electrical activity could be observed and analyzed easily. In the frequency domain, the distribution of energy spectrum of a special band can easily be distinguished normality and abnormality. 30608 T00401030608 ^x Laboratory information system (LIS) is a key tool to manage laboratory data in clinical pathology. Our department has developed an information system for routine hematology using down-sized computer system. We have used an IBM 486 compatible PC with 16MB main memory, 210 MB hard disk drive, 9 RS-232C port and 24 pin dot printer. The operating system and database management system were SCO UNIX and SCO foxbase, respectively. For program development, we used Xbase language provided by SCO foxbase. The C language was used for interface purpose. To make the system use friendly, pull-down menu was used. The system connected to our hospital information system via application program interface (API), so the information related to patient and request details is automatically transmitted to our computer. Our system interfaced with fwd complete blood count analyzers(Sysmex NE-8000 and Coulter STKS) for unidirectional data tansmission from analyzer to computer. The authors suggests that this system based on down-sized computer could provide a progressive approach to total LIS based on local area network, and the implemented system could serve as a model for other hospital's LIS for routine hematology. 30609 T00401030609 ^x To develop an artificial bone substitute that is gradually degraded and replaced by the regenerated natural bone, the authors designed a composite that is consisted of calcium phosphate and collagen. To use as the structural matrix of the composite, collagen was purified from human umbilical cord. The obtained collagen was treated by pepsin to remove telopeptides, and finally, the immune-free atelocollagen was produced: The cross linked atelocollagen was highly resistant to the collagenase induced collagenolysis. The cross linked collagen demonstrated an improved tensile strength. 30618 T00401030618 ^x This paper is a study on the design of adptive filter for QRS complex detection. We propose a simple adaptive algorithm to increase capability of noise cancelation in QRS complex detection with two stage adaptive filter. At the first stage, background noise is removed and at the next stage, only spectrum of QRS complex components is passed. Two adaptive filters can afford to keep track of the changes of both noise and QRS complex. Each adaptive filter consists of prediction error filter and FIR filter The impulse response of FIR filter uses coefficients of prediction error filter. The detection rates for 105 and 108 of MIT/BIH data base were 99.3% and 97.4% respectively. 30619 T00401030619 ^x To develop an artificial bone substitute that is gradually degraded and replaced by the regenerated natural bone, the authors designed and produced a composite that is consisted of calcium phosphate and collagen. Human umbilical cord origin pepsin treated type I atelocollagen was used as the structural matrix, by which sintered or non-sintered carbonate apatite was encapsulated to form an inorganic-organic composite. With cross linking atelocollagen by UV ray irradiation, the resistance to both compressive and tensile strength was increased. Collagen degradation by the collagenase induced collagenolysis was also decreased. 30620 T00401030620 ^x We have developed a monoleaflet polymer valve as an inexpensive and viable alternative, especially for short-term use in the ventricular assist device or total artificial heart. The frame and leaflet of the polymer valve were made from polyurethane, To evaluate the hemodynamic performance of the polymer valve a comparative study of flow dynamics past a polymer valve and a St. Jude Medical prosthetic valve under physiological pulsatile flow conditions in vitro was made. Comparisons between the valves were made on the transvalvular pressure drop, regurgitation volume and maximum valve opening area. The polymer valve showed smaller regurgitation volume and transvalvular pressure drop compared to the mechanical valve at higher heart rate. The results showed that the functional characteristics of the polymer valve compared favorably with those of the mechanical valve at higher heart rate. 30621 T00401030621 ^x Explosive evaporative removal process of biological tissue by absorption of a CW laser has been simulated by using gelatin and a multimode Nd:YAG laser. Because the point of maximun temperature of laser-irradiated gelatin exists below the surface due to surface cooling, evaporation at the boiling temperature is made explosively from below the surface. The important parameters of this process are the conduction loss to laser power absorption (defined as the conduction-to-laser power parameter, Nk), the convection heat transfer at the surface to conduction loss (defined as Bi), dimensionless extinction coefficient (defined as Br.), and dimensionless irradiation time (defined as Fo). Dependence of Fo on Nk and Bi has been observed by experiment, and the results have been compared with the numerical results obtained by solving a 2-dimensional conduction equation. Fo and explosion depth (from the surface to the point of maximun temperature) are increased when Nk and Bi are increased.To find out the minimum laser power for explosive evaporative removal process, steady state analysis has been also made. The limit of Nk to induce evaporative removal, which is proportional to the inverse of the laser power, has been obtained. 30622 T00401030622 ^x N1 and N2 gross neural action potentials were measured from the round window of the guinea pig cochlea at the onset of the acoustic stimuli. N1-N2 audiograms were made by means of regulating stimulant intensities in order to produce constant N1-N2 potentials as criteria for different input tone pip frequencies. The lowest threshold was measured with an input tone pip I5 dB SPL in intensity and 12 KHz in frequency when the animal was in normal physiological condition. The procedure of experimental measurements is explained in detail. This experimental approach is very useful for the investigation of the Cochlear function. Both noN1inear and active functions of the Cochlea can be monitored by N1-N2 audiograms. 30623 T00401030623 ^x In electrical impedance tomography(EIT), we use boundary current and voltage measurements toprovide the information about the cross-sectional distribution of electrical impedance or resistivity. One of the major problems in EIT has been the inaccessibility of internal voltage or current data in finding the internal impedance values. We propose a new image reconstruction method using internal current density data measured by NMR. We obtained a two-dimensional current density distribution within a phantom by processing the real and imaginary MR images from a 4.77 NMR machine. We implemented a resistivity mage reconstruction algorithm using the finite element method and sensitivity matrix. We presented computer simulation results of the mage reconstruction algorithm and furture direction of the research. 30624 T00401030624 ^x A new method of digital image analysis technique for discrimination of cancer cell was presented in this paper. The object image was the Thyroid eland cells image that was diagnosed as normal and abnormal (two types of abnormal: follicular neoplastic cell, and papillary neoplastic cell), respectively. By using the proposed region segmentation algorithm, the cells were segmented into nucleus. The 16 feature parameters were used to calculate the features of each nucleus. A9 a consequence of using dominant feature parameters method proposed in this paper, discrimination rate of 91.11% was obtained for Thyroid Gland cells. 30625 T00401030625 ^x An electrical stimulator was designed to induce locomotion for paraplegic patients caused by central nervous system injury. Optimal stimulus parameters, which can minimize muscle fatigue and can achieve effective muscle contraction were determined in slow and fast muscles in Sprague-Dawley rats. Stimulus patterns of our stimulator were designed to simulate electromyographic activity monitored during locomotion of normal subjects. Muscle types of the lower extremity were classified according to their mechanical property of contraction, which are slow muscle (msoleus m.) and fast muscle (medial gastrocneminus m., rectus femoris m., vastus lateralis m.). Optimal parameters of electrical stimulation for slow muscles were 20 Hz, 0.2 ms square pulse. For fast muscle, 40 Hz, 0.3 ms square pulse was optimal to produce repeated contraction. Higher stimulus intensity was required when synergistic muscles were stimulated simultaneously than when they were stimulated individually. Electrical stimulation for each muscle was designed to generate bipedal locomotion, so that individual muscles alternate contraction and relaxation to simulate stance and swing phases. Portable electrical stimulator with 16 channels built in microprocessor was constructed and applied to paraplegic patients due to lumbar cord injury. The electrical stimulator restored partially gait function in paraplegic patients. 30626 T00401030626 ^x Two-Dimensional modelling of the Cochlear biomechanics is presented in this paper. The Laplace partial differential equation which represents the fluid mechanics of the Cochlea has been transformed into two-dimensional electrical transmission line. The procedure of this transformation is explained in detail. The comparison between one and two dimensional models is also presented. This electrical modelling of the basilar membrane (BM) is clearly useful for the next approach to the further. Development of active elements which are essential in the producing of the sharp tuning of the BM. This paper shows that two-dimension model is qualitatively better than one-dimensional model both in amplitude and phase responses of the BM displacement. The present model is only for frequency response. However because the model is electrical, the two-dimensional transmission line model can be extended to time response without any difficult. 30627 T00401030627 ^x A method has been proposed for the fully automatic detection of left ventricular endocardial boundary in 2D short axis echocardiogram using geometric model. The procedure has the following three distinct stages. First, the initial center is estimated by the initial center estimation algorithm which is applied to decimated image. Second, the center estimation algorithm is applied to original image and then best-fit elliptic model estimation is processed. Third, best-fit boundary is detected by the cost function which is based on the best-fit elliptic model. The proposed method shows effective result without manual intervention by a human operator. 30628 T00401030628 ^x The intelligent trajectory control method that controls moving direction and average velocity for a prosthetic arm is proposed by pattern recognition and force estimations using EMG signals. Also, we propose the real time trajectory planning method which generates continuous accelleration paths using 3 stage linear filters to minimize the impact to human body induced by arm motions and to reduce the muscle fatigue. We use combination of MLP and fuzzy filter for pattern recognition to estimate the direction of a muscle and Hogan's method for the force estimation. EMG signals are acquired by using a amputation simulator and 2 dimensional joystick motion. The simulation results of proposed prosthetic arm control system using the EMf signals show that the arm is effectively followed the desired trajectory depended on estimated force and direction of muscle movements. 30638 T00401030638 ^x A new neural network architecture for the recognition of patterns from images is proposed, which is partially based on the results of physiological studies. The proposed network is composed of multi-layers and the nerve cells in each layer are connected by spatial filters which approximate receptive fields in optic nerve fields. In the proposed method, patterns recognition for complicated images is carried out using global features as well as local features such as lines and end-points. A new generating method of matched filers representing global features is proposed in this network. 30659 T00401030659 ^x An implementation scheme of the magnetic nerve stimulator using a switching mode power supply is proposed. By using a switching mode power supply rather than a conventional linear power supply for charging high voltage capacitors, the weight and size of the magnetic nerve stimulator can be considerably reduced. Maximum output voltage of the developed magnetic nerve stimulator using the switching mode power supply is 3, 000 volts and switching time is about 100 msec. Experimental results or human nerve stimulations using the developed stimulator are presented. 30768 T00401030768 ^x In this paper, we describe the design methodology and specifications of the developed module-based bedside monitors for patient monitoring. The bedside monitor consists of a main unit and module cases with various parameter modules. The main unit includes a 12.1" TFT color LCD, a main CPU board, and peripherals such as a module controller, Ethernet LAN card, video card, rotate/push button controller, etc. The main unit can connect at maximum three module cases each of which can accommodate up to 7 parameter modules. They include the modules for electrocardiograph, respiration, invasive blood pressure, noninvasive blood pressure, temperature, and SpO2 with Plethysmograph.SpO2 with Plethysmograph.

• Journal of Yeungnam Medical Science
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• 제10권2호
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• pp.451-474
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• 1993

전신마취, 부위 또는 국소 마취시, 그리고 향부정맥제로 술중 및 중환자실에서 흔히 쓰이는 lidocaine의 용량과, 국소 마취제로 인한 중추 신경계의 독성을 예방 또는 중단시키기 위해 사용되는 diazepam의 전투여시 이로 인한 심혈관계 변화 및 lidocaine의 혈중농도를 관찰, 측정하여 환자의 관리 및 치료에 도움을 얻고자 본 실험을 하였다. Nitrous oxide, halothane으로 마취된 개에서 근육이완제 사용 후 조절호흡하에서 혈중 이산화탄소를 35-45mmHg로 유지하면서 국소 마취체인 lidocaine의 용량을 100 mcg/kg/min, 200 mcg/kg/min, 300 mcg/kg/min로 각각 30분간 지속적 침제하면서, diazepam 전투여 유무에 따른 심혈 역학치의 변화 및 lidocaine의 혈중농도를 측정하고, 억제된 심혈관계에 $CaCl_2$를 투여하여 회복 정도를 관찰하였던 바 아래와 같은 결과를 얻었다. Lidocaine의 지속적 침제량이 증가됨에 따라 심혈관계의 억제가 심하게 나타났으며 평균 동맥압, 심장지수, 일회 박출지수, 좌심실 박출 작업지수, 우심실 박출 작업지수 등은 감소하였고 (p<0.05), 폐동맥 쐐기압, 중심 정맥압, 전신혈관 저항지수 등은 증가하였으나 (p<0.05), 심박동수, 평균 폐동맥압, 폐혈관 저항지수의 변화는 거의 없었다. Lidocaine 100 mcg/kg/min 지속적 침제시는 diazepam을 투여한 II군에서만 평균 동맥압의 의의있는 감소를 보였으며 (p<0.05), lidocaine의 혈중농도는 diazepam투여하지 않은 I군에서는 $3.97{\pm}0.22$에서 $4.48{\pm}0.36$ mcg/ml 범위였고 II 군에서는 $3.70{\pm}0.32$에서 $4.10{\pm}0.22$ mcg/ml범위였다. Lidocaine 200 mcg/kg/min의 지속적 침제시는 I군에서는 평균 동맥압의 감소, 중심정액압의 증가를 나타내었고 (p<0.05), II 군에서는 심장지수의 감소, 폐동백 쐐기압의 증가를 나타내었으며 (p<0.05), lidocaine의 혈중농도는 I군은 $7.50{\pm}0.66$에서 $7.91{\pm}0.77$ mcg/ml, II군에서는 $7.64{\pm}0.79$에서 $8.23{\pm}1.18$ mcg/ml범위로 증가하였다. Lidocaine 300 mcg/kg/min의 지속적 침제시는 I군에서는 평균동맥압, 일회 박출지수, 좌심실 박출 작업지수의 감소가 있었고 (p<0.05), 폐동맥 쐐기압, 중심 정맥압, 전신혈관 저항지수의 증가를 나타내었다 (p<0.05). II군에서는 심장지수, 일회 박출지수, 좌심실 박출 작업지수의 감소가 있었으며 (p<0.05), 폐동맥 쐐기압, 중심 정맥압, 전신혈관 저항지수의 증가를 나타내었다 (p<0.05). 그러나 심박동수, 폐동맥압의 변화는 거의 관찰할 수 없었다. 또한 이때의 혈중 lidocaine의 농도는 I군에서는 $11.30{\pm}2.11$에서 $11.83{\pm}0.59$ mcg/ml범위 로, II군에서는 $12.95{\pm}0.71$에서 $13.79{\pm}0.82$mcg/ml의 범위로 나타내었다. $CaCl_2$ 투여 후는 억제된 심장지수, 일회 박출지수, 전신혈관 저항지수, 폐혈관 저항지수, 좌심실 박출작업지수 및 우심실 박출 작업지수는 회복시켰으나 (p<0.05), 폐동맥 쐐기압, 중심정맥압 등은 오히려 억제시켰다 (p<0.05). 이상에서 자율신경계에 손상이 없으며 산혈증 및 과탄산증이 없는 개에서는 lidocaine의 높은 혈중 농도치에서도 혈역학에 내성이 있었으며, ljdocaine의 중추신경계 독성의 예방 및 치료 목적으로 사용되는 diazepam의 전투여 시에도 추가적인 심혈관계의 억제가 없음을 알 수 있었다. 그러나 자율신경계 이상이 있거나 자율신경계를 억압할 수 있는 약을 사용할 때 또는 산혈증, 과탄산증 및 저산소증이 동반된 환자에 사용할 때에는 세심한 주의가 요할 것으로 생각된다.

• Clinical and Experimental Pediatrics
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• 제50권9호
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• pp.891-895
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• 2007

목 적 : ADEM은 급성 중추 신경계의 탈수초성 질환으로 병태 생리학적 기전은 확실히 밝혀지지 않았으나 대부분 바이러스 감염 또는 예방 접종 후 수일에서 수주일 경과 한 후에 발병하며, 면역학적 기전이 관여 하는 것으로 알려져 있다. 임상 양상과 예후에 있어서도 다양하게 나타나며, 대부분은 단상성의 경과를 보이는 양성 질환으로 알려져 있다. 뇌 자기공명영상 병변은 전형적인 경우 주로 백질에서만 관찰되나 심부 회백질을 침범하는 경우도 드물지 않게 보고 되고 있다. 이에 다양한 임상 증상과 예후가 뇌 병변의 위치에 의한 것이라 생각되어, 후향적으로 자기공명영상 소견과 의무기록지를 통하여 조사하였다. 방 법 : 1995년 1월부터 2003년 8월까지 경희대학교 소아과에 ADEM으로 입원한 환자 21명을 의무 기록을 토대로 조사하였다. 자기공명영상 소견에 따라 1군은 백질에 국한된 다중 또는 단일 병변, 뇌실 주위 및 소뇌의 병변도 포함된 경우로 분류하였으며, 2군은 심부 회백질 또는 피질 병변으로 백질을 침범하는 경우로 분류하였다. 두 군간에 선행 증상이나, 발병 시 신경학적 증상, 뇌 척수액 소견, 신경학적 후유증을 비교분석 하였다. 결 과 : 두 군에 있어 선행 증상의 빈도를 보면 아무런 선행 증상 없이 발병한 경우가 38.1%로 가장 많았으며 상부 호흡기 감염 증상이 28.6%였고, 두 군간에 선행 증상에 대한 통계학적 차이는 없었다. 발병 당시 증상을 보면 경련이 76.2%, 두통과 구토 증상이 47.6%, 의식의 변화가 38.1%로 관찰되었으며 두 군간에 통계학적 차이가 없었다. 검사 결과 백혈구 증다증이 38.1%, 뇌척수액 소견상 세포 증다증이 76.2%에서 보였으며, 뇌척수액 내 단백질 증가가 28.6%에서 관찰되었으며 두 군간에 통계학적 차이는 없었다. 예후에 있어서도 15명인 71.4%가 정상화 되었으며 지속된 경련은 19%, 운동 장애는 19%에서 보였으며 두 군간에 통계학적 차이가 없었다. 결 론 : 이번 연구에서 병변의 차이에 따른 임상 양상과 예후에 있어 차이가 없는 것으로 관찰되나, 다양한 증상과 다양한 병변 및 예후를 보이고 있어 수많은 다른 면역학적 기전을 가진 이종성 질환이 아닌지 의심된다. 아직까지 ADEM의 진단 기준은 임상 증상과 자기공명영상 소견에 의존하여 다소 불분명하다. 이에 ADEM에 대한 연구가 더 필요할 것이라 생각되며, 아울러 초기 자기공명영상 검사와 추적 관찰에 있어 좀더 세심한 주의와 연구가 필요하겠다.

• Journal of Chest Surgery
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• 제37권4호
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• pp.313-321
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• 2004

폐동맥하 심실중격결손을 동반한 양대혈관 우심실기시증에서 동맥전환술은 심실내 교정의 제한된 적응증과 동맥전환술의 우수한 임상성적으로 인해 최근 이 기형의 선택적 치료법으로 자리잡고 있다. 이 기형에 대한 동맥전환술의 단기 및 중기 성적을 검토하였다. 대상 및 방법 1994년 8월부터 2002년 7월까지 8년 동안 동아대학교 병원에서 심실중격결손증 교정과 동맥전환술을 시행한 폐동맥하 심실중격결손을 동반한 양대혈관 우심실기시증 환자 13명을 대상으로 후향적 조사를 하였다. 양대혈관 우심실기시의 진단은 50% rule을 적용하였다. 중심나이와 평균체증은 각각 27일(범위, 3-120일)과 3.8$\pm$0.7kg (범위, 2.92-5.3kg)이었다. 대동맥궁기형은 6명(46.2%)에서 동반되었고 모두 일차 완전교정(one-stage repair)으로 교정되었다. 양대혈관의 위치관계는 좌우로 위치한 것이 8예(61.5%), 전후로 위치한 것이 5예(38.5%)였다. 관상동맥의 형태는 1LCx-2R과 좌관상동맥이 폐동맥의 뒤로 돌아가는 형태가 각각 6예씩(46.2%)이었으며 1명(7.7%)에서 벽속 좌관상동맥기형이 관찰되었다. 심실중격결손의 확장 및 패치를 이용한 우심실유출로 성형술이 각각 1명(7.7%)에서 시행되었다 좌우 대혈관 위치관계를 갖고 있는 3명(23.1%)을 제외한 모든 환자에서 Lecompte 술식을 시행하였다. 결과: 3예(23.1%)의 수술사망이 발생하였다. 3예 모두 대동맥궁기형을 갖고 있었던 경우였다. 수술 생존자의 평균추적기간 41.3$\pm$30.7개월(범위 1.7-79.1개월) 동안 만기사망은 1예(10%)로 술 후 5개월 뒤 중추신경계 합병증으로 사망하였다. 1예(10.0%)에서 압력차 30mmHg 이상의 폐동맥판 협착이 발견되었고 2예에서 좌폐동맥 협착으로 풍선확장술이 필요하였으며 이 중 1예(10%)에서 술 후 52개월만에 재수술이 필요하였다. 무증상의 중등도 대동맥판 폐쇄부전증이 1예(10%)에서 발견되었다. 수술사망을 포함한 5년 생존율은 68.3%였다. 결론: 대동맥궁기형을 동반한 폐동맥하 심실중격결손의 양대혈관 우심실기시증 환자에서는 높은 수술사망률을 보였으나 동반하지 않은 경우는 낮은 수술사망률과 재수술률을 보여 동맥전환술이 이 심기형에서 유용한 수술방법으로 고려될 수 있을 것이라고 생각한다.

• 한국재난정보학회 논문집
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• 제11권1호
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• pp.135-147
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• 2015

최근 지하공동구(Underground Common Utility Tunnels)는 도시민이 일상생활을 영위하는데 필요한 전기, 통신, 상수도, 도시 가스, 하수도뿐만 아니라 냉난방시설, 진공 집진관, 정보처리케이블 등의 시설물을 2종 이상 공동으로 수용하기 위한 지하시설물로서 국가의 중추기능을 담당하는 시설이지만, 화재 사고시 신속한 대처가 힘들고 각종 케이블 연소시 발생하는 유독가스 및 연기에 의해 공동구 내에 진입하여 진압하기가 힘들다. 따라서 화재발생시 막대한 재산피해 및 통신두절 등 국가의 중추신경이 마비됨은 물론 시민불편사항을 초래하게 된다. 따라서 본 논문은 지금까지 발생 되어온 국내,외 공동구 화재사례에서 화재발생의 주요원인으로 전기공사로 인한 합선 및 가연성케이블에 의한 열화접촉으로 화재가 발생하는 것이 대다수를 차지하고 있음에 착안하여 실제 공동구 모형을 제작하고 화재를 재현함으로서 과학적으로 화재의 성상을 분석하는데 그 목적이 있다. 화재실험은 지하공동구 내에 정온식 감지선형 감지기(Line type fixed temperature detector), 방화문(Fire door), 연결살수설비(Connection deluge set), 및 환기설비를 설치하고, 송 배전케이블은 일정구간 내화(Fireproof)도료로 도장하며, 난방관은 내화 피복된 상태에서 실험하였다. 그 결과 Type II의 경우 최고온도가 $932^{\circ}C$로 측정되었고, 일정한 온도에서 정온식감지선형감지기가 화재위치를 정확하게 수신반에 표시되었다. 그리고 Type III의 경우인 송 배전케이블은 일정구간 내화도료로 도장한 것은 내화성능이 없는 것으로 나타났고, 내화피복(Fireproof covered)된 난방관은 약 30분 정도의 내화성능이 있는 것으로 나타났다. 또한 화재뮬레이션 결과는 실물화재시험시의 화재하중(Fire load)을 입력하여 실시한 결과로서 최고온도가 $943^{\circ}C$로 실물화재실험시의 $932^{\circ}C$와 거의 일치 하였다. 따라서 공동구 화재하중만으로 화재시뮬레이션을 실시하여 화재성상에 대한 예측이 가능한 것으로 판단되며 시뮬레이션으로 얻은 열방출률(Heat release rate), 연기층의 높이, 산소(O2), 일산화탄소(CO), 이산화탄소(CO2)의 농도 등의 결과 값들은 실제 화재실험시의 값으로 적용시킬 수 있는 것으로 판단된다. 향후 본 연구에서 구축한 국내 지하공동구 화재사고에 대한 실험자료 및 매년 지속적으로 화재사례들을 분석하여 축적하고 법 규정 및 관리 메뉴얼 등을 보완함으로써 국내 지하공동구 화재사고에 대한 보다 신뢰성 있는 정보를 제공해 줄 수 있을 것이며, 효과적이고 체계적으로 지하공동구의 신설 및 유지 관리 보수에 기여할 것으로 기대된다.

• 생명과학회지
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• 제21권6호
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• pp.796-804
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• 2011

본 연구에서는 파의 항염증 효과를 밝히고 그 생화학적 기전 해석을 위해 LPS로 활성화된 BV2 microglia를 이용하여 iNOS, COX-2 및 염증성 cytokine의 발현 및 그 산물에 미치는 파 추출물의 영향을 조사하였다. 그 결과 파 추출물은 LPS 처리에 의한 BV2 세포의 iNOS의 발현을 전사 및 번역 수준에서 처리 농도 의존적으로 억제시켰으며, 특히 파 전체 에탄올 추출물(EEWA)의 효과가 가장 탁월하였다. LPS로 유도한 COX-2의 mRNA 및 단백질 발현 역시 파 추출물 처리에 의하여 감소되었으며 뿌리 에탄올 추출물(EERA) 처리군에서 가장 현저한 억제가 관찰되었다. 아울러 염증 반응의 또 다른 주요인자인 염증성 cytokine들(TNF-${\alpha}$, IL-$1{\beta}$ 및 IL-6)의 mRNA 변화를 조사한 결과 파 추출물이 대체적으로 이들 cytokine의 발현을 억제하는 경향을 보였으며, 최종산물인 TNF-${\alpha}$와 IL-6의 생성량 역시 유의한 수준은 아니었으나 감소하는 경향을 보였다. 본 연구의 결과는 파의 추출물은 iNOS, COX-2 및 염증성 cytokine의 발현을 조절함으로서 신경염증 반응을 효과적으로 억제하며, 향후 지속적인 연구가 필요하지만 신경 보호 작용에 탁월한 효능이 있음을 보여주는 것으로 생각된다.