• Journal of environmental and Sanitary engineering
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• v.7 no.2
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• pp.95-110
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• 1992

Much progress has been made in understanding the subcellular events of the human lung injuries after acute exposure to environmental air pollutants. Host of those events represent oxidative damages mediated by reactive oxygen species such as superoxide, hydrogen peroxide, and the hydroxy, free radical. Recently, nitric oxide (NO) was found to be endogenously produced by endothelial cells and cells of the reticulo-endothelial system as endothelialderived relaxation factor (EDRF) which is a vasoactive and neurotransmitter substance. Together with superoxide, NO can form another strong oxidant, peroxonitrite. The relative importance of exogenous sources of $N0/N0_2$ and endogenous production of NO by the EDRF producing enzymes in the oxidative stresses to the heman lung has to be elucidated. The exact events leading to chronic irreversible damage are still yet to be known. From chronic exposure to oxidant gases, progressive epithelial and interstitial damages develop. Type I epithelial cells become thicker and cover a smaller average alveolar surface area while thee II cells proliferate instead. Under acute damages, the extent of loss of the alveolar epithelial cell lining, especially type II cells appears to be a good predictor of the ensuing irreversible damage to alveolar compartment. Interstitial matrix undergo remodeling during chronic exposure with increased collagen fibers and interstitial fibroblasts. However, Inany of these changes can be reversed after cessation of exposure. Among chronic lung injuries, genetic damages and repair responses received particular attention in view of the known increased lung cancer risks from exposure to several air pollutants. Heavy metals from foundry emission, automobile traffics, and total suspended particulate, especially polycystic aromatic hydrocarbons have been positively linked with the development of lung cancer. Asbestos in another air pollutant with known risk of lung cancer and mesothelioma, but asbestos fibers are nonauthentic in most bioassays. Studies using the electron spin resonance spin trapping method show that the presence of iron in asbestos accelerates the production of the hydroxy, radical in vitro. Interactions of these reactive oxygen species with particular cellular components and disruption of cell defense mechanisms still await further studies to elucidate the carcinogenic potential of asbestos fibers of different size and chemical composition. The distribution of inhaled pollutants and the magnitude of their eventual effects on the respiratory tract are determined by pollutant-independent physical factors such as anatomy of the respiratory tract and level and pattern of breathing, as well as by pollutant-specific phyco-chemical factors such as the reactivity, solubility, and diffusivity of the foreign gas in mucus, blood and tissue. Many of these individual factors determining dose can be quantified in vitro. However, mathematical models based on these factors should be validated for its integrity by using data from intact human lungs.

• Journal of Sericultural and Entomological Science
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• no.11
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• pp.63-68
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• 1970

The induction of polyhedroses in the silkworm, Bambyx mari L., was investigated treating the 5th instar larvae just after eodysis with high temperature (hot water bath at 40$^{\circ}C$ for 5 minutes or dry heat shock at 40$^{\circ}C$ for 30 minutes) and low temperature (5$^{\circ}C$ for 24 hours). The results obtained were as follows; 1. Comparing between the frequency of nuclear and cytoplasmic polyhedroses induced by cold and heat treatments (hot water bath at 40$^{\circ}C$ for 5 minutes), the induction ratio of the former is clearly less than that of the latter. But if the larvae tested with cold were left at room temperature (25$^{\circ}C$) for 30-120 minutes till the next hot water bath (40$^{\circ}C$) for 5 minutes and water bath (20$^{\circ}C$) for 5 minutes, treatments, the frequency of induced cytoplasmic polyhedrosis was more than that in the case of cold or hot water bath treatment alone. 2. The frequency of nuclear and cytoplasmic polyhedrosis induced by cold and successive heat (dry heat shock at 40$^{\circ}C$ for 30 minutes), left at room temperature (25$^{\circ}C$) ti11 the second treatment, the frequency of nuclear polyhedrosis was less than that of cytoplasmic polyhedrosis. 3. The reaction of nuclear polyhedra to stains also differs sharply from that of the cytoplasmic type. In a smear of nuclear polyhedra on a slide staining with Giemsa solution remains unstained against a stained back ground, in contrast to this, the cytoplasmic polyhedra take up stain readly.

• The Korean Journal of Nuclear Medicine
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• v.24 no.2
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• pp.237-243
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• 1990

Pulmonary embolism demands rapid and accurate diagnosis. And ventilation imaging has greatly improved the diagnostic accuracy of pulmonary embolism in addition to perfusion imaging. Agents currently used include xenon-133, krypton-81m and technetium-99m radioaerosols. However radioactive gases are compromised by availability and cost for krypton-81m, radiation dose, gamma energy and non?physiologic behaviour for xenon-133. Radioaerosols of technetium-99m componds are rapidly cleared from the lung after inhalation, and their relative low effeciency (specific radioactivity) and wide distribution of particle sizes make them also suboptimum. A new ventilation agent, Technegas is a suspension of structured graphite ellipsoids with diameter below 20nm, labelled with $^{99m}Tc$ in a carrier gas of Argon. This report describes the authors' clinical experience with Technegas. This is the first reported clinical study of this agent in Korea. A comparison of Technegas and $^{99m}Tc-DTPA$ aerosol was performed in 12 patients with various pulmonary diseases such as COPD, pulmonary tuberculosis and pleural effusion. All patients were studied with $^{99m}Tc-DTPA$ aerosol inhalation and Technegas ventilation. In both studies image quality was assessed (1) semiquantitatively by scoring bronchial and gastric activity, (2) subjectively by direct visual comparison of peripheral lung images and (3) quantitatively by computing the peripheral penetration index(PI) for each lungs. The bronchial activites were seen in 7 out of 12 cases with $^{99m}Tc-DTPA$ aerosol and in 5/12 with Technegas. The gastric activities were seen in 5/12 and 1/12 cases respectively. The average values of PI were 61.26% with $^{99m}Tc-DTPA$ aerosol and 69.20% with Technegas (p>0.05). Using $^{99m}Tc-DTPA$ aerosol, COPD patients showed deposition in the central airways with poor visualization of the peripheral areas of the lungs. In Technegas studies these phenomena were less prominent, and the examination is well tolerated by pateients and requires only a minimum of patient cooperation. With superiority of easy availability and handling, better physical characteristics and favorable Image quality, Technegas is a Promising agent for lung ventilation scanning.

• Science of Emotion and Sensibility
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• v.14 no.1
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• pp.117-126
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• 2011

This study investigates the physical properties and manufacturing method of shape memory fabric for emotional garment made by polypropylene. For this purpose, polypropylene(PP) POY and SDY were texturized using low temperature and constant length heat treatment texturing technologies, respectively. The shape memory fabrics made using these texturized PP yarns were woven with two kinds of PET and PTT shape memory yarns on the air-jet loom and the various physical properties of four kinds of shape memory fabrics were measured and discussed. The tenacity and breaking strain of PP texturized yarns treated by low temperature and constant length heat treatment showed high weaving efficiency and the wet thermal shrinkage of PP textured yarns was shown less than 1.5%, dry thermal shrinkage was ranged between 3% and 5%, which means thermal stability compared to the PTT textured yarn with high thermal shrinkage, 5~8%. The shape memory characteristics of PP shape memory fabrics measured by Toray method showed five grade as same value as PTT shape memory fabric. The heat keeping property of the PP shape memory fabric showed 56% higher value than that of PTT shape memory fabric. The water repellency of PP shape memory fabric measured by spray method showed five grade as same value as PTT shape memory fabric treated with water repellent agent. Especially, shape memory properties of PP shape memory fabric measured by 3-D image and camera measurement methods showed similar characteristics to the PTT shape memory fabric.

• Tuberculosis and Respiratory Diseases
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• v.43 no.5
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• pp.805-811
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• 1996

Congenital cystic adenomatoid malformation of the Lung(CCAM) is characterized by anomalous fetal development of terminal respiratory structures, resulting in an adenomatoid proliferation of bronchiolar elements and cystic formation. CCAM was first described and differentiated from other cystic lung disease in the English literature by Ch'in and Tang in 1949. CCAN is a rare, potentially lethal form of congenital pulmonary cystic disease and the salient features of lesion are an irregular network of terminal respiratory bronchiole-like structures and macrocysts variably lined by pseudostratified ciliated columnar epithelium and simple cuboidal epithelium. Adult presentation of CCAM of the lung is so rare that only 9 cases have been reported in the literature of date. The pathogenesis of CCAM remains disputed and reseachers have variously proposed that the lesion represents a developmental anomaly, hamartoma, or a fonn of pulmonary dysplasia. Van Dijk and Wagenvoort divided CCAM into three subtypes : cystic, intermediated, and solid. These correspond to types I, II, and III of Stocker. In adults, the evaluation of cystic or multi cystic lung disease requires consideration of a differential diagnosis including the acquired lesions of lung abscess, cavitary neoplasm or inflammatory mass, bullous disease, bronchiectasis, and postionflammatory pneumatocele. Congenital lesions such as sequestration, bronchopulmonary-foregut anomalies, and bronchogenic cyst are also encounted. The definitive treatment for CCAM is complele removal of the involved lobe. Panial lobectomy leads to multiple complications, including severe post-operative infection. We report a case of CCAM in a 14-year-old female presentated with a pneumothorax and large bullae, who was treated by surgical remove of the involved lobe.

• Journal of dental hygiene science
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• v.2 no.2
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• pp.105-113
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• 2002

This study was aimed to investigate the practice on the infection control and dental waste disposal in dental clinic. The data used in this study had been collected in 100 dental clinics located in Seoul city from August to October, 2001. It was shown that examination instruments, oral surgery instruments, and periodontal instruments were almost sterilization in dental clinic. It was high in the recognition of individual protection but it was low in the degree of practice. Therefore, the practice in infection control is very important to dental team for safety of patients and operators.

• Tuberculosis and Respiratory Diseases
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• v.38 no.1
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• pp.8-15
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• 1991

It has been well known that the integrity of airway epithelium is important in development of bronchial hyperreactivity and bronchial asthma. But the mechanisms involved are still unclear. To evaluate that airway epithelium is able to modulate the contraction of guinea pig tracheal smooth muscle, we investigated the responsiveness of intact and epithelium-denuded tracheal strips to histamine and acetylcholine. And to evaluate whether cyclooxgenase products play a role in this modulatory mechanism, we also investigated the effect of indomethacin pretreatment on the tracheal responsiveness to histamine. Results were as follows: 1) In guinea pig tracheal smooth muscle the presence of airway epithelium significantly reduced the response to histamine. 2) In the presence of indomethacin dose-response curves and $EC_{50}$ values were similar between intact and epithelium-denuded tracheal strips, that is, indomethacin abolished the influence of epithelium on the contracion of tracheal smooth muscle. 3) The response of tracheal smooth muscle to acetylcholine was similar both in the presence and absence of epithelium. These results suggest that airway epithelium of guinea pig may generate an inhibitory signal to decrease the response of tracheal smooth muscle to histamine and cyclooxygenase products may contrbute to the modulation of airway epithelium on the contracion of tracheal smooth muscle.

• Tuberculosis and Respiratory Diseases
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• v.38 no.2
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• pp.135-142
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• 1991

We reviewed 15 cases of mesothelioma of the pleura, of which three cases were localized benign form and 12 cases were malignant diffuse form. The tumors were distributed equally in both sexes, and occured most commonly in fifth to seventh decades. The history of exposure to asbestos was present in only one case. The chief complaints were mainly chest pain and dyspnea. Associated symptoms were cough, sputum, hemoptysis, weight loss, anorexia, chill. On physical examination, unilateral, decreased breathing sound was main feature. The simple chest radiograph showed masses in all localized mesotheliomas (100%) and in 2 diffuse mesotheliomas (17%). 8 cases of diffuse mesotheliomas (67%) showed unilateral pleural effusions. Pleural effusions were mainly bloody (67%), and almost all were exudates. In all localized mesotheliomas, final diagnosis was made by open thoracotomy. In diffuse mesotheliomas, final diagnosis was made by open thoracotomy in 7 cases, chest wall mass biopsy in 2 cases, thoracoscopic biopsy in 1 case, pleural biopsy in 1 case, and pleural biopsy combined with axillary lymph node biopsy in 1 case. Localized mesotheliomas were treated by simple excision with good prognosis. In diffuse mesotheliomas, surgical treatment (pleuropneumonectomy, pleurectomy), chemotherapy, or radiotherapy, alone or in combination, were used with dismal prognosis. The prognostic factors were not found due to the small number of cases, incomplete follow up, and early drop out.

• Tuberculosis and Respiratory Diseases
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• v.38 no.1
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• pp.1-7
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• 1991

To study the frequency of the underlying disease of the diffuse pulmonary infiltrates in korea, we ansalyzed retrospectively 982 patients who were seen at nine university hospitals and one general hospital in Seoul area. The results are folloing: 1) Among the total 982 patients, 490 patients were male and 492 patients were female. The mean age was 44.3 years. 2) The most common etiology was milliary tuberculosis (38%), which was followed by, idopathic pulmonary fibrosis (27%), pulmonary fibrosis associated with collagen-vascular disease (15%), and diffuse pulmonary infiltrates by malignancy (10%). 3) Amon the connective tissue disease which was accompanied by the interstitial lung disease, rheumatoid arthritis was the most common disease (43%), systemic lupus erythematosus was the 2nd (28%), and progressive systemic sclerosis was the 3re (16%). 4) Among 101 cases of malignant disease, lung was the most frequent primary site (31%), which was followed by stomach (28%), thyroid (16%), and breast (6%). 5) For the diagnosis of the underlying disease of pulmonary infiltrates, the transbronchial lung biopsy was performed in 21% of the patients and open lung biopsy was done in 7%.

• Weed & Turfgrass Science
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• v.5 no.1
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• pp.10-16
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• 2016

Proper actions such as discard, return or manufacturing should be taken to imported plants contaminated with quarantine weeds. Heat-treatment has been used as a processing method in many countries such as U.S., Australia, Canada as well as Korea. This study was carried to find appropriate heat-treatment methods for devitalizing dodder seeds mixed with plant seeds. Two species of dodder seeds and six imported seeds were treated for 1, 5, 10, 15, 30, 45 minutes or 1, 2, 4, 5, 6, 8 hours at the temperatures of $75^{\circ}C$, $80^{\circ}C$, $85^{\circ}C$, $90^{\circ}C$, $95^{\circ}C$, $100^{\circ}C$ and $120^{\circ}C$. According to the study, dodder seeds were devitalized at the conditions of $85^{\circ}C$ for 2 hours, $90^{\circ}C$ for 30 minutes, $95^{\circ}C$ and $100^{\circ}C$ for 15 minutes, $110^{\circ}C$ for 10 minutes and $120^{\circ}C$ for 5 minutes. Meanwhile, seed vigours of Cosmos bipinnatus and Callistephus chinensis had no difference when compared with untreated control at the heat-treatment conditions of $85^{\circ}C$ for 2 hours, $90^{\circ}C$ for 30 minutes.