• Korean Journal of Veterinary Research
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• v.32 no.3
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• pp.381-387
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• 1992

Gill epithelia of normal rainbow trout fingerlings and abnormal ones suffering bacterial gill disease by experimental infection were examined by transmitting electron microscopy (TEM) and scanning electron microscopy (SEM). TEM observations revealed that Flavobacterium branchiophila consisted of slender rods measuring 0.5 by 5 to $8{\mu}m$, and they had which were long, thin, flexible filaments measuring approximately 4 nm by $1{\mu}m$, and packed together to organize into bundles. Morphological alterations of the diseased epithelia started at hypertrophy of the lamellar epithelium. F branchiophila attached to the gill surface of infected fish through pili with a regular distance, and did not invade into gill tissue. In SEM observations, normal surface ultrastructure of epithelial cell in the outermost layer were characterized by a typical labyrinth-like structure branching and anastomosing microridges on the cell surface. Hyperplastic lesions in experimentally infected gill were most serious at near the tips. Each filament exhibited a club-like, and fusion between the filaments was sometimes observed at their tips. On the surface of gill filaments, thread-like bacterial cells attached and were entangled. The bacterial cells almost covered the surface. After immersion in 5 % NaCl, the cell of F branchiophila, however, appeared to be indeterminate shape.

• Journal of fish pathology
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• v.18 no.2
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• pp.125-131
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• 2005

Amoebic gill disease of flounder, Paralichthys olivaceus was diagnosed at commerical culture facility in South Korea. The amoeba was identified as a species of the genus Neoparamoeba based on the morpholgical characteristics of trophozoites. Transmisson electron microscopy revealed the presence of a symbiotic organism, parasome in the cytoplasm and dense glycocalyx on the surface of the trophozoites. They lacked the boat-shaped microscales on the surface and contained numerous vacuoles and channels, mitochondria in the cytoplasm. Colonization of amoebae on gill tissue elicited extensive fusion and hyperplasia of gill lamella.

• Applied Microscopy
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• v.39 no.4
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• pp.319-324
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• 2009

Morphology of the gill in Lateolabrax japonicus was investigated after staining the gill, as a result, we found the gill is composed of gill raker, gill arch, gill filament and gill lamellae. The number of gill raker was 7~10 in the upper and 13~18 in the lower. Ultrastructure of the gill in Lateolabrax japonicus were examined by means of the light and transmission electron microscopes. The gill have primary filament and secondary filament (lamellae). The following cells are identified and described: pavement cell, pillar cell, blood cell, mucose cell and chloride cell etc. Simple epithelial layer consists of squamous epithelium contained large nucleus, intracellular organelles etc. and the surface is covered with some of microridges. The lamella pillar structures are characterized by the axial microtubules and lateral membrane interdigitations. The mucous cells were globular in shape, and had almost the mucous granules of same size with various electron density. Chloride cells contain a lot of mitochondria and specifically developed tubular systems.

• The Korean Journal of Malacology
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• v.27 no.1
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• pp.69-76
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• 2011

Gill morphology and ultrastructure of the spiny top shell, Batillus cornutus were described using light and electron microscopy (SEM and TEM). The spiny top shell, Batillus cornutus has bipectinate gill. The epithelial layer of gill filament was simple and composed of columnar epithelium, ciliated cell, mitochondria-rich cell and secretory cell. Microvilli were well-developed on the free surface of columnar epithelial cell. The epithelial cells are connected to the neighboring cells with intercelluar junctions at the apico-lateral surface. The cilia and microvilli were commonly observed on the free surface of ciliated cell. Tubular mitochondria appeared in the apical cytoplasm, and connected ciliary rootlet. Mitochondria-rich cells contained a oval-shaped nucleus in the basal area. And majority of cytoplasm was occupied by well-developed mitochondria. Result of AB-PAS (pH 2.5) and AF-AB reaction showed that secretory cells contained mainly acidic carboxylated mucosubstances. Secretory cells are unicellular glands and can be divided into four types (A, B, C and D) depending on the cell shape and ultrastructure of secretory granules.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.3
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• pp.283-289
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• 2003

The effect on kidney, gill, and hepatopancreas of juvenile olive flounder, Paralichthys olivaceus were investigated by histological method under limit concentration of effulent of PCBs for 60 days. The free surface of epithelial cell layer in the renal tubules of kidney showed a strong positive reaction in alcian blue during all exposure period. There were also observed swelling of hemocyte in glomerulus and macrophage. At 60 days after exposure, epithelium of the renal tubules was fused and some of organism $(20\%)$ showed damage of glomerulus and eosinophlic cell in epithelium of the renal tubules. The phenomena such as the activation and increase of the chloride cell, and swelling of hemocyte in the capillary of gill were observed during all exposure period. At 60 days after exposure, swelling of the gill filament and mucous cell appeared in gill and some of organism $(30\%)$ showed swelling of the gill lamellar. Swelling of hemocyte in the capillary of hepatopancreas was observed and the free surface of epithelial layer of the bile duct showed positive reaction in alcian blue during all exposure period. Degenerated zymogen in the pancreas and swelling of the hepatocyte were occurred at 60 days after exposure.

• The Korean Journal of Malacology
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• v.30 no.1
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• pp.51-56
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• 2014

Morphology and histochemistry of gill of the abalone, Haliotis discus hannai were described using light microscopy and scanning electron microscopy (SEM). The abalone has bipectinate gill of protobranch. The cilia and microvilli were well-developed on the free surface of the gill filaments. The epithelial layer of gill filament was simple and composed columnar epithelia and mucous cells. Result of AB-PAS (pH 2.5 and 1.0) and AF-AB (pH 2.5) reaction showed that mucous cells contained mainly acidic carboxylated mucosubstances.

• Journal of Fisheries and Marine Sciences Education
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• v.22 no.4
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• pp.501-507
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• 2010

The ceramic contained paint was made to replace the lead sinker for gill-net with coated lead sinker. The ceramic contained paints were coated in various conditions on the lead sinker with 19g of weight and the optimal coating condition was studied. The adaptability of the coated lead sinker was checked through the anti durability test and fishing operation with gill-net. The case of "Main material 70 wt% + Urethane thinner 30 wt% (Main material 700 $m{\ell}$ + Thinner 300 $m{\ell}$)" showed the best in the coating characteristics depending on the combination ratio of the ceramic paint contained. The coated lead sinker dried at $100^{\circ}C$ inside oven was superior to the drying in the room temperature in its surface glossiness and anti durability and faster drying time than the one dried in normal temperature. The quadruple layers of coating on lead sinker with 4 times of dipping and drying application showed the super anti durability in the coating characteristics depending on the frequency of dipping. When press is applied to the coated lead sinker, the coated layer is not detached from the sinker. In addition, the coated lead sinker was not damaged or peeled at the fishing operation about 2 months in various depths within 50m and by the materials at the bottom (sand, stone and gravel stone) and it was in good condition.

• Journal of fish pathology
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• v.4 no.2
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• pp.95-100
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• 1991

Saprolegnia diclina, which was the pathogen causing death in snake fishes(Channa argus) at culture farm, was investigated using scanning electron microscope. It was found that Saprolegnia diclina infection caused snake fishes to fail gas change in the gills. Cell lysis as well as edematous disease and hyperplasia as a result of Saprolegnea diclina attachment on the surface of gills were observed. The granules, the mean diameters of which ranged from 6 to $7\;{\mu}m$, attaching on the surface of gills were found to be secondary zoospores of Saprolegnia diclina. The failures of gas exchange in the gill cells and circulation as a result of the osmotic dilution of the blood were supposed to be the main cause of death.

• Journal of fish pathology
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• v.15 no.3
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• pp.117-119
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• 2002

A kind of leeches, Trachelobdella sp was detected on the inside surface of the opercle of wild crucian carp, Carassius cuvieri (21.5 cm in length and 238.5 g in weight) at a reservoir for agriculture in ChungNam Province of Korea in March, 2002. Two or three round transparent spots on the opercle could be easily detected. The fish also showed severe anemia and dorsally darking in the gill lamellae. The parasites was identified as Trachelobdella sp. on the basis of morphological characteristics such as suckers, body segmentation and lateral diverticula. As the parasites fed on host blood after attaching on the inside surface of the opercle by means of the posterior sucker, they caused severe anemia and petechial haemorrhge on the gill of infested fish. Heavy infestation of the parasite resulted in dath of fish because of large amount of blood loss.

• Transactions of the Korean hydrogen and new energy society
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• v.8 no.1
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• pp.43-47
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• 1997

A new type of anode materials in form of nanocrystalline composite powders has been developed that offers the potential for dramatically improved discharge capacity and initial activation rate. The composites are synthesized by ball milling of two components - a major component (basic component) having high hydrogen capacity and a minor component (surface activator) with good electrocatalytic activity. The capacity increase observed by ball milling with surface activator. The ball-milled composite materials are easier to activate than the non ball-milled basic component.