• Food Science and Biotechnology
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• 제16권6호
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• pp.988-993
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• 2007

The protective effect of the water extract of Fraxinus rhynchophylla leaves (FLE) was determined using an animal model of acetaminophen (AAP)-induced nephrotoxicity. The BALB/c male mice used in this study were divided into 3 groups; the normal, AAP-administered, and FLE-pretreated AAP groups. A single dose of AAP induced necrosis of renal tubules and congestion along with edema to a remarkable degree as observed by hematoxylin and eosin stain, and also increased the numbers of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL)-positive renal tubular epithelial cells. Blood urea nitrogen and plasma creatinine levels were determined to be significantly higher in the AAP group than in the normal group. However, FLE pretreatment resulted in an attenuation of renal tubule necrosis. Regeneration and dilatation of renal tubules were noted, and the numbers of TUNEL-positive cells were reduced in the FLE-pretreated groups. In an effort to detect the bioactive compounds exerting protective effects in FLE, the analysis of phenolic compounds via gas chromatography/mass spectrometry (GC/MS) were performed, and identified esculetin and esculin. The present study indicates that these compounds may exert a protective effect against AAP-induced nephrotoxicity.

• 한국통신학회논문지
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• 제28권10A호
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• pp.830-837
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• 2003

위성망 이용의 증가로 정지궤도의 이용밀도가 높아짐에 따라 비정지궤도로서 고타원형궤도에 대한 관심이 증가되고 있다. 현재 ITU-R에서는, 고타원형궤도를 이용하는 고정통신위성시스템과 지상고정통신시스템이 주파수를 공유하는 4GHz 및 11GHz 대역에서 지상고정통신시스템을 효과적으로 보호하면서 고타원형궤도 위성시스템을 원활하게 운용할 수 있는 고타원형궤도 위성의 전력속밀도 제한에 관한 연구가 수행되고 있다. 본 연구는 현재 ITU-R에서 논의되고 있는 고타원형궤도 위성시스템의 전력속밀도 마스크들에 대해서 실제 지상고정통신시스템으로의 간섭량을 계산하여 우리나라가 위치하는 중위도 지역에서 지상고정통신시스템을 효과적으로 보호할 수 있는 전력속밀도 마스크를 제안하고자 하였다.

• Radiation Oncology Journal
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• 제7권2호
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• pp.157-169
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• 1989

Radiological and clinical evidences indicate that hyperthermia combined with irradiation produce a significant improvement in therapeutic effect of cancer The experiences obtained from 90 rats' kidney A single dose of irradiation ranged from 6Gy, 8Gy and 10Gy was delivered on the rat's kidney. The combined therapy group had the same irradiation after hyperthermia at $42\~44^{\circ}C$ for 30 minutes. Microscopic examination and calculation of thermal enhancement ratio were carried out, and the results were as follows: 1. In the group of hyperthermia alone, there were moderate glomerular congestion and mild tubular degeneration on light microscopic examination. 2. In the group of irradiation alone, tubular degeneration was noted in 6Gy irradiation and its severity was increased along with radiation dose. 3. In the group of hyperthermia combined with irradiation, tubular degeneration and necrosis were appeared in 6Gy and 10Gy irradiation, respectively. 4. On electron microscopic examination, proximal convoluted tubular and glomerular changes in irradiation group were similar to that of combined with hyperthermia, and its severity was increased along with observation periods. 5. Thermal enhancement ratio (TER) was 1.0 after evaluation of histipathologic changes in rat's kidney, with combination therapy.

• 대한의용생체공학회:의공학회지
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• 제40권4호
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• pp.125-131
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• 2019

As a non-invasive method for alleviating allergic rhinitis, there has been a recent ongoing research in the treatment of light from light emitting diodes (LEDs) and lasers. A total of 15 subjects diagnosed with allergic rhinitis were selected for this study. Red and near infrared light emitted from LEDs with wavelengths of 660nm and 940nm were illuminated three times daily (three minutes per cycle) for a total of two weeks. The degree of nasal congestion, runny nose, sneezing and nasal itching was evaluated by questionnaires before and after the test. Also, the serum IgE (Immunoglobulin E) was measured and compared before and after the test. As a result, the total score of symptoms of allergic rhinitis was decreased by 67% after the test (P<0.01). The level of IgE was decreased by 17% after the test (P<0.05). In conclusion, the non-invasive LED phototherapy method using red and near-infrared LED light was effective in alleviating symptoms of allergic rhinitis. There were no adverse effects or complications reported during and after the test.

• 국토계획
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• 제53권6호
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• pp.117-130
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• 2018

Heavy snow is a natural disaster that causes serious economic damage. Since snowfall has been increasing recently, there is a need for measures against heavy snowfall. In order to make a policy decision on heavy snowfall, it is necessary to estimate the precise amount of damage by heavy snowfall. The direct damage of the heavy snow is severe, however the indirect damage caused by the road congestion and the urban dysfunction is also serious. Therefore, it is necessary to estimate indirect damage of snowfall. The purpose of this study is to estimate the effects on the regional economy from the limitation in traffic logistics caused by heavy snow using the transport demand model and inoperability input-output Model. The result shows that the amount of production loss caused by the heavy snow is KRW 2,460 billion per year and if the period of snowfall removal is shortened by one day or two days, it could be reduced to KRW 1,219 or 2,787 billion in production loss.

• 한국항공운항학회지
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• 제29권4호
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• pp.96-104
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• 2021

Technological advances have recently led to the development of Urban Air Mobility (UAM) which is a small airplane being able to take off and land vertically. It is emerging as an alternative to transportation services in the city in the future because of the advantage of providing speed and congestion problem in cities like taxis. This research aim to study the user's acceptance of UAM. Based on the survey conducted abroad, the analysis was carried out based on th Technology Acceptance Model (TAM), by Davis et al. (1989). According to the data analysis results of 292 people, Technology, Reliability and Price effect perceived usefulness, which in turn effects Behavioral intention. UAM cannot be operated independently by a single company. It consists of partnerships with vehicles, transport platforms, batteries and other related company. To improve acceptance of UAM, it is required that collaboration between companies and support from government. And while UAM is being developed, research on acceptance from user's point of view should continue.

• 한방안이비인후피부과학회지
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• 제18권2호
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• pp.36-50
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• 2005

Background and Objectives: Allergic rhinitis is an allergic reaction characterized by sneezingm itchy nose, mouth and throat, congestion and/or nasal discharge. The offending allergenes are usually pollens, molds, dust mites and animal allergen. Recently, the incidence of infectious nasal diseases tend to decrease. However, allergic rhinitis has increased and treatment in most cases has only deat with the symptom. Tongkyu-tang was composed of sixteen crude drugs. The Oriental Medical References mention therapeutic effects of Tongkyu-tang on nasal obstruction, watery nasal discharg. And Tongkyu-tang has clinically been used for the treatment of common cold, headache, sternutation, rhinitis etc. Speacially Tongkyu-tang is one of the most frequently used medical treatment for the allergic rhinitis. Experimental studies were conducted to investigate for the effect of Tongkyu-tang on the changes of neutrophil segment, lymphocyte, total IgE and nassal tissue in allergic rhinitis of ovalbumin-inhalation rat. Meterial and Methods: Fifteen Sprague-Dawley rats were divided into three group: normal group, control group, experimental group. To induce the allergic rhinitis in control group and experimental group, rats were sentitized intraperitoneally with 0.1 % ovalbumin solution 3 times at intervals of I week. Then intranasal sensitization was performed by diffusing 0.1 % ovalbumin solution 3 times at intervals of 2 days. After that time, rat in the experimental group were oral administration treated by Tongkyu-tang for 28 days. We observed changes in nasal tissue; changes in the number of white blood cell, red blood cell and total Ig E; also changes in the segment of neutrophil and lymphocyte in blood. And we observed the changes of AST, ALT of three group. We used anova test statistically. Result: The number of leucocyte remained unchanged between three group. The number of erythrocyte was increased in experimental group and control group when compared with the normal group. The segment of neutrophil, in blood was decreased in experimental group when compared with the control group but, that was not significant statistically(p<0.05). The promotion of lymphocyte in blood was significantly decreased in experimental group when compared with the Control group(p<0.05). Total IgE was decreased in experimental group when compared with the control group but, that was not significant statistically(p<0.05). The cilium be well preserved in experimental group: the nasal tissue in experimental group was similar to in the normal group. Congestion and expantion of grandular cell in nasal submucosa, hypertropy of epithelium in nasal mucosa, acid mucus in epithelium and neutral mucus in subepithelium were decreased in experimental group when compared with the control group. Effect of Tongkyu-tang on the liver function were also studies in rats. Treatment of Tongkyu-lang did not affected on AST and ALT. Conclusion: Considering the above experimental results, it is suggested that oral administration treatment using Tongkyu-lang, without worry about liver function injury, decreased response on an Animal model with Allergic Rhinitis.

• 한국화재소방학회논문지
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• 제30권2호
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• pp.81-86
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• 2016

최근 국내 도심지 도로는 빈번한 교통정체가 발생하고 있다. 도심지 교통정체를 해소하기 위한 방안으로 국내에서는 대심도 복층터널에 대한 계획이 이루어지고 있다. 국내에서 계획되는 대심도 복층터널은 소형차 전용으로 계획되며 네트워크형의 구조를 가지고 있어 차량의 출입이 지하공간에서 이루어지고 있다. 이러한 네트워크형 대심도 복층터널은 터널의 단면 및 높이가 일반도로터널 보다 작고 차량의 출입으로 인한 교통풍의 작용으로 화재연기가 터널 승객의 대피보다 빠르게 전파되어 인명피해 발생이 예상된다. 따라서 본 연구에서는 국내 네트워크형 대심도 복층터널에 화재시 화재연기 확산지연을 방지하고자 화재연기 확산지연 장치 작동시 터널 차단면적에 터널 내 작용하는 유입풍의 저감효과를 분석하였으며, 분석결과 터널 차단면적이 50% 이상일 경우 터널 내 작용하는 풍속을 약 21% 저감시키는 효과가 나타났으며, 면적이 50% 이상일 경우 화재 연기의 확산속도를 약 21% 저감시켜 안전한 대피에 도움이 될 것이라 판단된다.

• Toxicological Research
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• 제24권1호
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• pp.51-58
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• 2008

The present study was designed to explore the immunotoxic effects of orally administered aluminum (AI) on pregnant rats (n = 60) and their growing fetuses and consequently on the animal wealth. The animals were randomly allocated into three equal groups of 20 rats each. The first group has no treatment and kept as a control (G1). The second and third groups of pregnant rats were treated orally with aluminum chloride at 345 mg/Kg b.wt. The second group (G2) received the tested compound from the $6^{th}$ day of gestation to the end of weaning, whereas the third group (G3) received the tested compound from the $15^{th}$h day of gestation to the end of weaning. Control and treated animals (dams and offspring) were immunized ip with (0.5 ml) 20% sheep red blood cell (SRBC) suspension seven days before the end of experiments. At the end of exposure, ten dams and ten offspring from each group were used for assessment of cell-mediated immunity and a similar number of animals were sacrificed for evaluating the humoral immune response and serum protein profile. Aluminum chloride exposure of dams ($G_2&G_3$) caused significant suppression of both cell mediated and humoral immune responses in the obtained offsprings compared to the control group ($G_1$) without any significant effect on the immune responses of these dams. Moreover, the serum total globulins, albumin/ globulin (A/G) ratio and gamma globulin fraction were significantly decreased in the treated dam's offsprings compared to the corresponding controls while the serum total protein and all serum protein fractions showed non significant difference between the control and treated dams and between the two treated dam groups themselves. There were no histopathological changes observed in thymus, spleen and liver of the control and treated dams. Thymus of treated dam's offsprings (G2) showed lymphoid depletion in both cortex and medulla. Their spleens showed lymphoid depletion in the white pulps and congestion with hemosiderosis in the red pulps. Liver of treated dam's offsprings showed dilation and congestion of its central vein with degenerative changes in the hepatocytes. These histopathological changes were more severe in G2 than in G3 offsprings. It can be concluded that gestational and/ or lactation exposure of pregnant dams to AI chloride caused suppression of both cellular and humoral immune responses of their offsprings.

• 대한약리학회지
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• 제2권2호
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• pp.3-22
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• 1966

An experimental study was done on rabbits to observe the effects of several anticlonorchial drugs on the pathology of the liver infested with Clonorchis sinensis. After two months of infestation with Clonorchis sinensis by giving $400{\sim}500$ metacercariae by mouth, hexachlorophene, chloroquine 2,2' methylenebis (3,4,6 trichlorophenoxy acetic acid) and Hetol were administered orally and follow up macro-and microscopic studies of the liver pathology were done in 2 to 3 days, one month, 2 months and 3 months after the completion of medications. The results obtained in this study are as follows: 1. In both groups which were administered hexachlorophene piperazine 20mg/kg for seven days or 8mg/kg for 18 days, the macroscopic findings of the liver after 3 months revealed only minimal changes of the color and consistency The histopathological findings were the reduction of fibrosis, pseudolobulation, proliferation and adenomatous hyperplasia of bile ducts, and regeneration of liver parenchyma. 2. In groups which were administered chloroquine phosphate 20mg/kg for 18 days or 40mg/kg for 5 days, and also in groups which were administered dithiazanine iodide 30mg/kg for 18 days or 60mg/kg for 5 days, no significant findings of recovery were observed either macroscopically or microscopically. 3. In the group which was given 20mg/kg of 2,2' methylenebis(3,4,6 trichlorophenoxy acetic acid) for 5 days, prominent healing of the damaged tissues was observed after 2 months, revealing the decrease of fibrous tissue, caliber of bile ducts and adenomatous hyperplasia of the epitherial cells of the bile ducts, and regenerationof liver parenchyma. 4. In the group which was given Hetol 200mg/kg for 5 days, swelling, congestion and eddish-brown discoloration of the liver were noted macroscopically after 3 days of completion of drug administration. Hemorrhage, congestion, necrosis and degeneration of the parenchyma were observed microscopically After 10 days, liver appeared almost normal macroscopically, but marked fat degeneration was noted microscopically. After 2 months, the liver was almost normal in gross appearence with only slight atrophy and also marked healing was observed microscopically, i. e. decrease of fibrous tissue and reduction of the previously enlarged bile duct and the regeneration of the liver parenchyma.