• Korean Journal of Head & Neck Oncology
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• v.2 no.1
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• pp.67-73
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• 1986

An unusual polypoid laryngeal tumor has been studied with light and electron microscopy. In light microscopic section, there were two components: a squamous cell carcinoma and a sarcomatoid spindle cell population. Transitional zone between these two components was found. The electron micrographs demonstrated the presence of slender bundles of tonofilaments in many tumor cells. Desmosomes were present, but few in number and poorly developed. Findings suggest this laryngeal tumor as a spindle cell variant of squamous cell carcinoma.

• Carbon letters
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• v.5 no.2
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• pp.75-80
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• 2004

The studies on activated carbon prepared from walnut shell and groundnut shell were undertaken to ascertain the effect of initial state of precursor and activation process on the development of porosity in the resulting activated carbon. Walnut shell based carbon shows the presence of cellular pores while Groundnut shell based carbon shows fibrillar pore structure. The adsorption parameters, characterization of product and scanning electron microscopic studies carried out showed the presence of mainly Micro, Meso and Macro porosity in carbon prepared from Walnut shell while mainly micro porosity was observed in Groundnut shell based activated carbon. An interrelationship between the adsorption efficiency and porosity in terms of quality control parameters, for before and after activation, was validated through the scanning electron microscopic data.

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.788-792
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• 2013

A shortcoming of using transmission electron microscopy (TEM) for structural analysis via electron diffraction is the relatively large error of the measurements as compared to X-ray diffraction. To reduce these errors, various internal standard methods from earlier studies have been widely used. We developed a new device to facilitate the application of internal standard methods in preparation of TEM grids used for nanopowder analysis. Through the application of a partial mask on the TEM grid, both the internal standards and the research materials can be loaded on the same grid. Through this process, we conducted a TEM analysis that compared synthetic hydroxyapatite (HAp) nanopowder to bone apatite from a bovine femur. We determined that the accuracy of the d-spacing measurements of the HAp and bone powders could be improved to better than 1% after statistical treatments of the experimental data. By applying a quarter mask, we loaded four different nanoparticles on a single TEM grid, with one section designated for the internal standard.

• Biomedical Science Letters
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• v.6 no.2
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• pp.109-118
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• 2000

The bronchus and alveoli from young rats have been examined by electron microscope following the exposure of cigarette smoking. Experimental animals were exposed to the sidestream smoke in an experimentally designed cage for 45 minutes per day during four weeks. In the smoking group, transmission electron micrographs of lung tissues showed a large number of neutrophils with electron densed several lysosomes, numerous macrophages with many small lysosomes, and many residual bodies in alveolar space. Scanning electron micrographs revealed that the ciliated epithelial cells in bronchus of smoking group were replaced by goblet cells including loss of cilia, and increased cell size of many goblet cells in bronchus. These results depicted that the ultrastructural changes are due to the passive smoking, involving airway cell Injury.

• Biomedical Science Letters
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• v.4 no.2
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• pp.77-86
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• 1998

Age-related changes in the lens capsule and epithelium of cataractous patients, ranging from 20 to 7o years old, were studied by means or LM, immunohistochemistry, and TEM. The lens capsule was divided into four zones; the anterior, subanterior, middle, and basal zone. The van Gieson staining reaction for collagen was prominent at the anterior and subanterior parts of the lens capsule. The reaction was more decreased in the elder group than the younger group. The collagen type IV reaction was prominent at the anterior zone of the lens capsule and around the cell. The reaction was more decreased in the elder group than the younger group. 3. The Periodic Acid Shiff-Alcian Blue reaction for mucopolysaccharide was prominent at the anterior zone of the lens capsule. The reaction was more decreased in the elder group than the younger group. The Apoptotic reaction was prominent at the nucleus of the lens epithelial cell. In the elder the cataractous group, the number of the apoptotic cells was more decreased. The electron microscopic change of lens epithelial cells were characterized by the increase of lateral fold and the cytoplasm with various vacuoles and Golgi complex. In the basal part, lens epithelial cell protruded toward the lens capsule in the 20-year-old group. The basal part of the 40-year-old group was flattened and covered with the cytoplasmic processes of adjacent cells. In the 60-year-old group, the mass of rough filaments separated lens capsule and the basal part of the lens epithelial cell. The electron microscopic change of the middle part of lens capsule was characterized by the aggregation of electron dense materials in the 40-year-old group, and the appearance of filamentous materials and the decrease of electron dense granules in the 60-year-old group.

• Applied Microscopy
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• v.36 no.1
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• pp.7-16
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• 2006

A new remote access system for a 1.3 MV high voltage electron microscope has been developed. Almost all essential functions for HVEM operation, huck as stage control, specimen tilting, TV camera selection and image recording, are successfully embedded into this prototype of the remote system. Particularly, this system permits perfect and precise operation of the goniometer and also controls the high resolution digital camera via simple Web browsers. Transmission of control signals and communication with the microscope is accomplished via the global ring network for advanced applications development (GLORIAD). This fact makes it possible to realize virtual laboratory to carry out practical national and international HVEM collaboration by using the present system

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.444-445
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• 1989

• 한국전자현미경학회:학술대회논문집
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• 2005.11a
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• pp.121-124
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• 2005

• Applied Microscopy
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• v.3 no.1
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• pp.55-59
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• 1973

• Journal of Periodontal and Implant Science
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• v.6 no.1
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• pp.20.1-20.1
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• 1976