• Asian-Australasian Journal of Animal Sciences
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• v.17 no.9
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• pp.1188-1191
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• 2004

Two species of marine catfish, Arius maculatus and Osteogeneiosus militaris, belonging to family Ariidae were analysed electrophoretically for genetic variation in 6 enzymes, alcohol dehydrogenase (ADH), malate dehydrogenase (MDH), lactate dehydrogenase (LDH), glucose dehydrogenase (GDH), malic enzyme (ME) and superoxide dismutase (SOD). Eighteen individuals of each species were studied. Two loci MDH and ADH were polymorphic in both. Average heterozygosity in A. maculatus was 1.46, while it was 2.5 in O. militaris. The allele frequencies were used to estimate Nei's genetic distance (D). The D value was calculated to be 0.6879. Two isozyme loci, ME and SOD, were found to be the most reliable species specific markers. No tissue specific loci were observed for the enzymes studied, the bands being identical in each case. The genetic distance observed between O. militaris and A. maculatus in this study suggests that they would be more appropriately classified as species of the same genus rather than being assigned separate genera.

• Environmental Analysis Health and Toxicology
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• v.23 no.3
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• pp.195-200
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• 2008

Hydroxylated polychlorinated biphenyl (OH-PCBs)는 PCB의 CYP-dependent oxidation의 대사물로서 잠재적 독성이 강하고 지질친화성을 가지며 생물군에 지속적인 축적성을 나타낸다. OH-PCBs의 해독화 효능을 조사하기 위하여 channel catfish 간에서 glucuronidation을 통한 해독작용 가능성을 평가하고 biphenyl 구조에 다양한 염소치환의 구조적 차이점에 따른 영향을 비교 분석하여 보았다. Kinetic parameters에서 $K_m$과 $V_{max}$는 $192{\sim}871{\mu}M$, $869{\sim}1774$ pmo1/min/mg으로써 4'-OH-PCB35와 4'-OH-PCB69이 가장 높은 속도의 glucuronidation을 나타냈으며, 구조적 차이점에서 phenolic group에 한 개의 염소치환이 존재할 경우보다 두 개의 염소치환이 존재할 경우에 OH-PCBs(p<0.001)의 glucuronidation에 대한 $V_{max}$를 현저하게 낮추는 결과를 보였다.

• Proceedings of the Korean Biophysical Society Conference
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• 1998.06a
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• pp.35-35
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• 1998

Catfish retina contains cone- and rod-horizontal cells. Only the cone-horizontal cell (cone-HC) has an axon and axon terminal. We compared the distribution of excitatory and inhibitory receptors in axon terminals and somata to begin to learn about the distinct functions of these two structures.(omitted)

• Journal of Aquaculture
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• v.13 no.4
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• pp.359-362
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• 2000

Mitotic gynogenesis was induced in the far eastern catfish, Silurus asotus using UV-irradiated heterospecific sperm and cold shock treatment. Eggs were activated with the sperm of mud loach, Misgurnus mizolepis which has been irradiated with UV at dose of 9,000 ergs/$mm^2$. To determine the optimum duration required to prevent the first cleavage, a cold shock at 4$^{\circ}C$ with duration of 20, 30 or 40 min was applied to the eggs 50 min after activation. To induce diploidization of mitogenesis, the most effective protocol was to apply cold shock to 50-min old (after activation) eggs at 4$^{\Circ}C$ for 30min.

• Journal of Aquaculture
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• v.15 no.4
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• pp.275-277
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• 2002

To obtain baseline data required for ploidy induction in Silurus asotus, a species with enormous aquacultural potential, histological events related to early embryonic development at 24$\pm$0.5$^{\circ}C$ are described. The histological location of the one-celled embryos indicated that metaphase stage of the first cleavage occurs at 31 min after insemination, when the highest yield can be obtained for the chromosome set manipulation.

• Fisheries and Aquatic Sciences
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• v.3 no.3_4
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• pp.228-229
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• 2000

Trypanosoma sp. (Sarcomastigophora: Kinetoplastida) was found in the blood of the Korean catfish, Silurus asotus, for the first time in Korea. The morphological characteristics of Trypanosoma sp. in the present study were similar with those of T. carassii, T. tincae and T. danilewskyi. However, the free flagellum length of Trypanosoma sp. was obviously shorter than that of those species. The species identification was reserved until elucidating the pleomor-phism according to the phase of infection and the cross infectivity among fish species.

• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.54-54
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• 1999

Protein kinase modulation of gamma-aminobutyric acid C (GABA$_{c}$) currents in freshly dissociated catfish retinal cone-horizontal cell axon-terminals was studied under voltage clamp with the use of the whole cell patch-clamp technique. Responses to pulses of GABA were monitored in intracellular application of adenosin 3',5'-cycle monophophate (cAMP)-dependent protein kinase (PKA) and protein kinase C (PKC) activators, and their inhibitors or inactive analogues.(omitted)d)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.530-531
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• 2001

Out of 20 primers, 6 generated 1349 highly reproducible RAPD markers, producing approximately 5.2 polymorphic bands per primer in catfish(Sizurus asotus) population from Kunsan. The electrophoretic analysis of polymerase chain reaction-random amplified polymorphic DNAs (PCR-RAPD) products showed the middle levels of similarity between different individuals in population from Kunsan. That is to say, the degree of similarity varied from 0.40 to 0.54, with the average of 0.46, as calculated by bandsharing analysis. (omitted)

• Proceedings of the Korean Aquaculture Society Conference
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• 2006.05a
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• pp.550-551
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• 2006

• Journal of the korean veterinary medical association
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• v.52 no.10
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• pp.616-620
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• 2016