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High Resolution HC$_3$N Observations toward the Central Region of Sagittarius B2

  • H.S-Ching;Oh, M.ishi;M.Morimoto
    • Bulletin of the Korean Space Science Society
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    • 1993.10a
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    • pp.17-17
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    • 1993
  • 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.

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Responsiveness of Muscarinic and Alpha Adrenergic Activation on Endothelial Cell in Isolated Canine Renal Arteries (개 신동맥 내피세포의 무스카린성 및 알파 아드레날린성 수용체에 대한 작용)

  • Chung, Soo-Youn;Chang, Ki-Churl;Lim, Jung-Kyoo
    • The Korean Journal of Pharmacology
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    • v.25 no.1
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    • pp.43-51
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    • 1989
  • Responsiveness of muscarinic and alpha adrenoceptor activation on endothelial cells was studied in isolated canine renal artery rings. Ach (10-100 nM), dose dependently, relaxes endothelial intact rings precontracted with phenylephrine ($IC_{50}$ of Ach was 34.5 nM). Selective mechanical destruction of the endothelium transformed the activity of this substance from vasodilatation to vasoconstriction. Acetylcholine induced relaxations could be selectively inhibited competitively by atropine, but could not be inhibited by cyclooxygenase inhibitor. Methylene blue, however, an inhibitor of soluble guanylate cyclase activity, inhibited Ach as well as sodium nitroprusside (SNP) induced relaxation. Relaxation produced by prostacyclin was not modified by methylene blue. On the other hand, alpha adrenoceptor agonist did not relax but contract canine renal artery rings possessing an intact intima precontracted with U-46619. Clonidine, however, selective alpha-2 adrenergic agonist, is more susceptible than phenylepherine, selective alpha-1 adrenergic agonist, to the inhibitory effect of contraction. These results suggest that in canine renal artery rings, 1) muscarinic receptor is responsible for releasing endothelium dependent relaxation factor (EDRF). 2) alpha-1 and alpha-2 adrenergic receptors are present in canine renal artery. 3) relaxation via EDRF is antagonized by methylene blue, providing further evidence that EDRF acts through a cGMP mechanism.

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Effects of Cyclobuxine E on Two Distinct Types of Potassium-Activated Calcium Channels in an Intestinal Smooth Muscle (흰쥐 장관에 있어 칼륨에 의해 활성화되는 칼슘 채널에 대한 Cyclobuxine E의 영향)

  • Lee, Jong-Hwoa;Kwon, Jun-Tack;Cho, Byung-Heon;Choi, Kyu-Hong;Kim, Yu-Jae;Kim, Jong-Bae;Kim, Chun-Sook;Cha, Young-Deog;Kim, Young-Suk
    • The Korean Journal of Pharmacology
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    • v.25 no.1
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    • pp.53-58
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    • 1989
  • For several years, we investigated the pharmacological action of several substances isolated from Buxus microphylla var koreana Nakai, which had been used as folk remedies of malaria and venereal disease. Cyclobuxine $D(C_{25}H_{42}ON_2)$, a steroidal alkaloid, exerted an antiinflammatory action, hypotensive and bradycardic effects in rats. In the present study, we isolated alkaloid from the acetone-insoluble fraction of the strong bases of this plants. This alkaloid $(C_{25}H_{38}ON_2)$ was identified as a steroidal alkaloid contained a cyclopropane ring by physical and chemical methods. It is a derivative of cyclobuxine D and named cyclobuxine E. We examined the effect of cyclobuxine E on the contractile response induced by acetylcholine and two distinct types of potassium-activated calcium channels in an intestinal smooth muscle of the rat. Cyclobuxine E inhibited significantly the Ach-induced contraction. The isolated longitudinal muscle from the rat duodenum was immersed calcium-depleted potassium depolarizing solution. Ten minutes after, 1.8 mM $CaCl_2$ was added to muscle bath and elicited a biphasic increase in muscle tension. Cyclobuxine E produced an appreciable inhibition of both components of the mechanical response. In addition, Cyclobuxine E introduced at a point when the tonic response had reached its maximum level, caused the muscle to exhibit a rapid loss of tension. Based on these experimental results, we proposed the possibility that the inhibitory action of cyclobuxine E on the isolated rat duodenum may be due to inhibiting the transmembrane fluxes of calcium ion in potassium-activated calcium channels.

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Strength Evaluation of Sin91e-Radius Total Knee Replacement (TKR) (인공무릎관절의 단축법위 회전시 근력정가)

  • Wan, Jin-Young;Sub, Kwak-Yi
    • Journal of Life Science
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    • v.14 no.3
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    • pp.484-489
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    • 2004
  • Artificial joint replacement is one of the major surgical advances of the 21th century. The primary purpose of a TKA (Total Knee Arthroplasty) is to restore normal knee Auction. Therefore, ideally, a TKA should: (a) maintain the natural leverage of the knee joint muscles to ensure generating adequate knee muscle moments to accomplish daily tasks such as rising from a chair or climbing stairs;(b) allow the same range of motion as an complete knee; and (c) provide adequate knee joint stability. Four individuals (2 peoples after surgery one year and 2 peoples after surgery three years) participated in this study. All they were prescreened for health and functional status by the same surgeon who performed the operations. Two days of accommodation practice occurred prior to the actual strength testing. The isometric strength (KIN-COM III) of the quadriceps and hamstring were measured at 60$^\circ$ and 30$^\circ$ of knee flexion, respectively. During isokinetic concentric testing, the range of motion was between 10$^\circ$ to 80$^\circ$ of knee flexion (stand-to-sit) and extension (sit-to-stand). for a given test, the trial exhibiting maximum torque was analyzed. A 16-channel MYOPACTM EMG system (Run Technologies, Inc.) was used to collect the differential input surface electromyographic (EMG) signals of the vastus medialis (VM), vastus lateralis(VL), rectus femoris (RF) during sit-to-stand and stand-to-sit tests. Disposable electrodes (Blue SensorTM, Medicotest, Inc.) were used to collect the EMG signals. The results were as follows; 1. Less maximum concentric (16% and 21% less for 1 yew man and 3 years mm, respectively) and isometric (12% and 29%, respectively) quadriceps torque for both participants. 2.14% less maximum hamstrings concentric torque for 1 year man but 16% greater torque for 3 years mm. However, 1 year man had similar hamstring isometric peak torque for both knees. 3. Less quadriceps co-contraction by 1 year man except for the VM at 10$^\circ$-20$^\circ$ and 30$^\circ$-50$^\circ$ range of knee flexion.

The Alleviating Effects of Green Tea on N-Nitrosodimethylamine Toxicity to Mucins in the Rat Lingual Salivary Glands (흰쥐 혀침샘의 점액질에 미치는 N-Nitrosodimethylamine 독성에 대한 녹차의 완화 효과)

  • Cho, Eun-Ju;Jeong, Gil-Nam;Jo, Un-Bock
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.12
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    • pp.1568-1575
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    • 2008
  • This study was performed to determine alleviating effects of green tea (GT) on the N-nitrosodimethylamine (NDMA) toxicity to mucins in the rat lingual salivary glands. Sprague-Dawley rats were divided into five groups: untreated (Control), one week-NDMA administrated (NDMA), one week-GT administrated after NDMA for one week (NDMAGT), one week-NDMA administrated with GT (GTNDMA), and one-week NDMA administrated with GT after GT for one week (GTGTNDMA). The mucin properties were elucidated by periodic acid Schiff (PAS) reaction, alcian blue (AB) pH 2.5, AB pH 2.5-PAS, aldehyde fuchsin (AF) pH 1.7-AB pH 2.5, and high iron diamine (HID)-AB pH 2.5 staining. The lingual von Ebner's glands of NDMA group showed some changes such as contraction and destruction of the serous acini, decrease and disappearance of the cytoplasmic granules, vacuolation of cytoplasm, and the mucigenous duct cells. Also, in the lingual mucous glands, enlarged lumens, fused acini, disappearance of granules, vacuolation of cytoplasm, and mucigenous duct cells were observed. All the GT administrated groups had a tendency to recover. GTGTNDMA group recovered almost up to the state of the control group. The lingual von Ebner's glands of NDMA group showed a decrease of neutral mucin and the lingual mucous glands showed a decrease of both neutral and acidic mucins decreased in comparison with control group, although mucous acini secreting strong sulfomucin decreased while those secreting non-sulfomucin (sialomucin) increased. All the GT administrated groups had a tendency to recover. The degree of recovery in the GTNDMA group was stronger than in NDMAGT group and that of the GTGTNDMA group was almost up to the state of the control group. Plus, lingual von Ebner's glands of GTGTNDMA group contained much more neutral mucin than in the control group. In conclusion, it is suggested that NDMA exhibit the toxicity which affects on the mucin properties and which green tea alleviates.

Evaluation of Maternal Behavior between Normal Parturition and Expected Cesarean Section in Rats (자연 분만 및 예정된 제왕절개 수술 랫드에 있어서 모성 행동의 차이에 대한 검토)

  • Lee, S.K.;Kang, H.G.;Kim, I.W.;Jeong, J.M.;Hwang, D.Y.;Kim, C.K.;Chae, K.R.;Cho, J.S.
    • Journal of Embryo Transfer
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    • v.22 no.3
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    • pp.161-165
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    • 2007
  • Oxytocin is a neurohypophyseal hormone which has multiple functions in mammals. Mainly, oxytocin regulates milk ejection and has an effect on uterine contraction and is related to maternal behavior. Maternal behavior is believed to be suppressed by stress and facilitated by oxytocin. In the cesarean section, oxytocin may be administrated into uterus to promote uterine involution. The present study aimed to test the effect of oxytocin into uterus on maternal behavior of rats with cesarean section. It was measured the effects on maternal behavior of oxytocin infused into uterus in rats with cesarean section as a stressor. In the first experiment, pup survival rate of between a control group and a group with laparotomy as a stress in natural parturition rats was compared. In the second experiment, survival rate for 2 weeks and maternal pup searching behavior (MPSV) were observed in one cesarean sectioned group without oxytocin and the other cesarean sectioned group with oxytocin. Infanticide was observed in stressed group in the first experiment while a normal maternal behavior was observed in a control one. In the second experiment, MPSV was only observed in a cesarean sectioned group with oxytocin and infanticide was observed in two groups except one rat which is thought to be affected by oxytocin as operated relatively late. This is the first study to show that the administration of oxytocin into uterus in the cesarean section is not involved in the regulation of maternal behavior in rats. In conclusion, this study proves the needs of oxytocin into brain in cesarean section related rats model and further study of maternal behavior list, like MPSV.

Influence of Postmortem Storage Temperatures between $0{\sim}30^{\circ}C$ on the Physico-chemical Changes and Meat Qualities of Korean Native Beef Cattle (사후 저장온도 $0{\sim}30^{\circ}C$가 한우근육의 이화학적 변화와 육질에 미치는 영향)

  • Kim, Cheon-Jei;Park, Soo-Bong;Choi, Do-Young;Choe, Byung-Kyu;Ko, Won-Sik
    • Korean Journal of Food Science and Technology
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    • v.26 no.1
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    • pp.88-92
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    • 1994
  • The influence of the storage temperature between $0^{\circ}C$ and $30^{\circ}C$ on the biochemical, physical changes and meat qualities in the red muscle(M. sternomandibularis and M. mastoideus) of Korean native cattle postmortem were studied. The results obtained were summarized as follows; The pH-value during the first hours post mortem was dropped faster in storage temperature $0^{\circ}C$ than in $10^{\circ}C$, but the final pH-value reached after about 30 hrs. post mortem. The muscle which was stored in $30^{\circ}C$ reached the final pH within 10 hrs. The muscle which was stored in $0^{\circ}C$ showed the increased R-value at fast speed from the beginning. It reached maximum R-value after 20 hrs as it gradually increase showing low R-value by 10 hrs. in $10^{\circ}C$. The muscle which was stored in $0^{\circ}C$ shortened to about 46% after 10 hrs. It was contracted about 17% after 15 hrs in $10{\sim}20^{\circ}C$. The sarcomere length of Korean native cattle had the least contraction in $10^{\circ}C$ and it was contracted $18{\sim}20%\;(1.60{\sim}1.63\;{\mu}m)$ after 5 hrs., $45{\sim}46%$after 24 hrs in $0^{\circ}C$ and $30^{\circ}C$ which was generated cold shortening and rigor shortening. The meat that was stored in $0^{\circ}C$ and $30^{\circ}C$ showed about 2-fold higher shear force than it that was stored in $10^{\circ}C$ at postmortem 24 hrs. The meat that was stored in $10^{\circ}C$ at postmortem 24 hrs. showed drip loss less than 3% during the 9 days ripening period. The meat with cold shortening and rigor shortening showed the high drip loss.

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Establishment of a Radiation-Induced Fibrosis Model in BALB/c Mice (BALB/c 마우스를 이용한 방사선섬유증 모델 확립)

  • Ryu, Seung-Hee;Lee, Sang-Wook;Moon, Soo-Young;Oh, Jeong-Yoon;Yang, Youn-Joo;Park, Jin-Hong
    • Radiation Oncology Journal
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    • v.28 no.1
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    • pp.32-38
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    • 2010
  • Purpose: Although radiation-induced fibrosis is one of the common sequelae occurring after irradiation of skin and soft tissues, the treatment methods are not well standardized. This study aimed to establish the skin fibrosis mouse model by fractionated radiation for the further mechanism studies or testing the efficacy of therapeutic candidates. Materials and Methods: The right hind limbs of BALB/c mice received two fractions of 20 Gy using a therapeutic linear accelerator. Early skin damages were scored and tissue fibrosis was assessed by the measurement of a leg extension. Morphological changes were assessed by H&E staining and by Masson's Trichrome staining. TGF-${\beta}1$ expression from soft tissues was also detected by immunohistochemistry and PCR. Results: Two fractions of 20 Gy irradiation were demonstrated as being enough to induce early skin damage effects such as erythema, mild skin dryness, dry and wet desquamation within several weeks of radiation. After 13 weeks of irradiation, the average radiation-induced leg contraction was $11.1{\pm}6.2mm$. Morphologic changes in irradiated skin biopsies exhibited disorganized collagen and extracellular matrix fibers, as well as the accumulation of myofibroblasts compared to the non-irradiated skin. Moreover, TGF-${\beta}1$ expression in tissue was increased by radiation. Conclusion: These results show that two fractions of 20 Gy irradiation can induce skin fibrosis in BALB/c mice accompanied by other common characteristics of skin damages. This animal model can be a useful tool for studying skin fibrosis induced by radiation.

Extracellular $K^+$ Effects on the Mouse Aortic Endothelial Cell Contractility (쥐 대동맥 혈관 내피세포에서 세포 외 $K^+$에 의한 혈관 수축선 조절 기전)

  • 안재호;유지영
    • Journal of Chest Surgery
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    • v.36 no.12
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    • pp.887-893
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    • 2003
  • External stimuli increases intracellular (IC) $Ca^{2+}$, which increases extracellular (EC) $K^{+}$. To verify $K^{+}$ effects on the vascular contraction, we performed an experiment using mouse aortic endothelial cell. Meterial and Method: We examined the mouse aortic contractility changes as we measured the IC $Ca^{2+}$ change and ionic current by using the voltage clamp technique under different conditions such as: increasing EC $K^{+}$, removing endothelial cell, giving L-NAME (N-nitro-L-arginine methyl ester) which suppress nitric oxide formation, Ouabain which control N $a^{+}$ - $K^{+}$ pump and N $i^{2+}$ which repress N $a^{+}$-C $a^{2+}$ exchanger Result: When we increased EC $K^{+}$ from 6 to 12 mM, there was no change in aortic contractility. Aorta contracted with more than 12 mM of EC $K^{+}$. Ace-tylcholine (ACh) induced relaxation was inhibited with EC $K^{+}$ from 6 to 12 mM, but was not found after de-endothelialization or L-NAME treatment. ATP or ACh increased IC $Ca^{2+}$ in cultured endothelium. After maximal increase of IC $Ca^{2+}$, increasing EC $K^{+}$ from 6 to 12 mM made IC $Ca^{2+}$ decrease and re-decreasing EC $K^{+}$ to 6 mM made IC $Ca^{2+}$ increase. Ouabain and N $i^{2+}$ masked the inhibitory effect of endothelium dependent relaxation by increased EC $K^{+}$. Conclusion: These data indicate that increase in EC $K^{+}$ relaxes vascular smooth muscle and reduces $Ca^{2+}$ in the endothelial cells which inhibit endothelium dependent relaxation. This inhibitory mechanism may be due to the activation of N $a^{+}$- $K^{+}$ pump and N $a^{+}$-C $a^{2+}$ exchanger. $a^{+}$-C $a^{2+}$ exchanger.r.

$pD_2$ Value of Choline Esters on Motility of Isolated Rabbit Jejunum Segment (토끼의 적출장관 운동에 대한 Choline Esters의 $pD_2$)

  • Park, Joon Hyoung;Kim, Young Whan;Kim, Kil Soo
    • Current Research on Agriculture and Life Sciences
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    • v.7
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    • pp.231-235
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    • 1989
  • The effects of choline and choline esters(acetylcholine, methacholine, carbachol, bethanechol) on motility of isolated rabbit jejunum segment were examined and $pD_2$ values of each drugs were compared. The results were as follows. In choline, there were revealed that maximum effective concentration was $10^{-2}M$, $ED_{50}$ was $2.4{\times}10^{-3}M$, and $pD_2$ value was 2.619. In acetylcholine, there were revealed that maximum effective concentration was $10^{-4}M$, effect was hardly showin in $10^{-9}M$ concentration, $ED_{50}$ was $0.5{\times}10^{-5}M$, and $pD_2$ value was 5.154. In methacholine, there were revealed that maximum effective concentration was $10^{-5}M$, effect was hardly shown in $10^{-9}M$ concentration, $ED_{50}$ was $9{\times}10^{-7}M$, and $pD_2$ value was 6.045. In carbachol, there were revealed that maximum effective concentration was $10^{-5}M$, effect was hardly shown in $10^{-11}M$ concentration, $ED_{50}$ was $5.7{\times}10^{-7}M$, and $pD_2$ value was 6.244. In bethanechol, there were revealed that maximum effective concentration was $10^{-4}M$, effect was hardly shown in $10^{-8}M$ concentration, $ED_{50}$ was $3.3{\times}10^{-6}M$, and $pD_2$ value was 5.480. Choline and choline esters caused contraction on motility of isolated rabbit jejunum segment. The order of $pD_2$ values of drugs was carbachol, methacholine, bethanechol, acetylcholine and choline (in the descending order of potency).

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