• Korean Journal of Plant Resources
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• v.17 no.2
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• pp.161-168
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• 2004

Optimal regeneration conditions of ginseng transformants were studied. It has been known that Ferritin Light Heavy Chain (FLHC) gene remove the several heavy metal by combination, store and transport. To obtain the ginseng tolerant to heavy metal, binary vector was introduced in Agrobacterium by tri-parental mating and then Agrobacterium tumefaciens MP90/FLHC was selected on the AB media and MS media containing kanamycin. Explants were co-cultured with Agrobacterium tumefaciens MP90/FLHC, which contained NPT II as a selectable marker, tadpole ferritin heavy chain (FLHC) gene and human ferritin light chain gene and then a number of embryos were induced. The induced embryo transferred to shooting media consisting of MS medium supplemented with GA 10 mg/L. As a result of examination that induced the normal growth of transfomants, transformants showed the equivalent growth in both root and shoot on the media containing the 1/3 MS.

• Korean Journal of Ecology and Environment
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• v.42 no.1
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• pp.32-38
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• 2009

The hatching rate of the eggs of Triops longicaudatus (LeConte), an endangered tadpole shrimp species in Korea, was experimented in different levels of temperature (10, 15, 20, 25, 30, 35, 40, 45, and $50^{\circ}C$) under 24 L photoperiod conditions in incubator. Eggs of T. longicaudatus in this study were obtained from the adults collected from Andong-si, Gyeongsangbuk-do, Korea, in July 2006. The highest hatching rate was the 80.0 (${\pm}9.43$)% in average at $35^{\circ}C$. The thermal threshold for hatching was derived at $6.66^{\circ}C$. However, eggs were not hatched both at $10^{\circ}C$ and at $50^{\circ}C$ during the experimental period.

• The Journal of the Korean dental association
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• v.11 no.8
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• pp.525-530
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• 1973

True collagenolytic enzymes in animal tissues were first demonstrated by Gross and Lapiere (1962), who showed the ability of such an enzyme in the culture medium of living explants of tadpole tissue to degrade a specific substrate of undenatured collagen under physiological conditions. Recently, tumor-associated collagenolytic activity has been demonstrated in human neoplasm and in ascites V Carcinoma. This investigation have been peforme to determine whether or not a collagen lytic enzyme could e found in isolated solid Tawa sarcoma of Donryu female rat obtained the culture medium. The results were as follows. 1. 11.5mg% of hydroxyproline contained in Donryu rat skin collagen, which was extracted by 0.5M acetic acid. 2. Cultivation of solid Tawa sarcoma tissues on reconstituted rat skin collagen gels showed lysis of adjacent gel after 18 hours, and much more extensive lysis after 5 days. 3. Collagen substrate was not attacked by the common proteolytic enzymes, trypsin, pepsin, and pronase.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.9 no.1
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• pp.30-36
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• 1995

Until now, simple shielding is the only way to prevent harmful electromagnetic: wave from TV and monitor. In this study, we adopted special ceramics to Braun tube for radiating FIR ray. In experiment on living organisms, there was some differences between general and ceramics treated Braun tube. The chrysanthemunm the drosophila and the tadpole which were in front of ceramics treated Braun tube showed longer living activity than those in front of general tube. As a result, it is proved that the ceramics treated Braun tube offers good effects to living organisms.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.37-42
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• 2002

In ascidians, a primitive chordate, maternal cytoplasmic factors and inductive interactions are involved in the specification of cell fate in early embryos. The larval structure of ascidians is relatively simple, and the major mesodermal tissues of the tadpole larva are notochord, muscle and mesemchyme. Formation of muscle cells is a cell-autonomous process, and localized maternal macho-1 mRNA specify muscle fate in the posterior marginal zone of the early embryo. In contrast, inductive influence from endoderm precursors plays important roles in the specification of notochord and mesenchyme fates. FGF-Ras-MAPK signaling is involved in the induction of both tissues. The difference in responsiveness of the posterior mesenchyme and anterior notochord precursors is caused by the presence or absence of the posterior-vegetal egg cytoplasm, respectively. In these cases, directed signal may polarizes the responding cells and cause asymmetric cell divisions that operate in both the anterior and posterior regions.

• Parasites, Hosts and Diseases
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• v.35 no.2
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• pp.75-78
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• 1997

In uitro excystation studies were done on the metacercarial cysts of Echinostomn triuolvis obtained from the kidneys of naturally infected Rnna species tadpoles. Cysts were excysted in an alkaline trypsin-bile salts medium and the percentage of excystation was compared with that from previous studies done on cysts obtained from the kidneys of snails. The percentage of excystation of E. triuoluis metacercariae from tadpole kidneys was similar to that reported for previous studies on cysts obtained from experimentally infected gastropod hosts. The possible role of tadpoles as an agent for the transmission of Echinostomn and echinostomiasis to humans is discussed.

• Journal of Environmental Health Sciences
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• v.5 no.1
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• pp.66-70
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• 1978

This experiment is to search what some chemicals polluting water have an effect on the Rana nigromaculata Hallowell, in the survival rate and the metamorphosis speed from a tadpole to a young frog. 1. The fatal thickness by some agricultural chemicals and copper sulfate is different from one another. The fatal rate in the contrast group is 15 percent, and particulary Dithane M-45 is the most among the all reagents. 2. The effect on the anamorphosis is very severe. In the case of contrast group, it appears to stage 25, but it is not to appear at the group used agricultural chemicals. 3. The less the thickness of that is, the less the influence of the survival rate and the metamorphosis speed. 4. The density of the agricultural chemical is in inverse proportion to the survival rate and the metamorphosis speed, and the other side, the fatal rate is proportion.

• Animal Systematics, Evolution and Diversity
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• no.nspc3
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• pp.59-66
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• 1992

Triops longicaudatus(LeConte, 1846), a tadpole shrimp collected from ricefields at Ch'angnyong and Sarnchonp'o, Korea, is redescribed and illustrated. This is the first record of notostracan fauna in Korea.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.239-240
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• 2001

Collagenases are generally defined as enzymes capable of degrading the polypeptide backbone of native collagen under conditions which do not denature the protein. Two types of proteases with collagenolytic activity have been reported and thought to play different physiological functions. Metallo-collagenases, firstly discovered in tadpole tissue explants are zinc-containing enzymes requiring calcium for optimum activity and stability, and These enzymes have been widely studied from various mammalian tissues as well as from bacteria, such as Bacillus cereus, Clostridium histolyticum, Achromobacter, Vibrio alginolyticus and Clostridium perfringens and snake venoms. (omitted)

• Animal cells and systems
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• v.7 no.3
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• pp.221-225
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• 2003

The tadpole larva of the ascidian Halocynthia roretzi has two sensory pigment cells in its brain vesicle. To elucidate the temporal requirement for FGF signaling in formation of the pigment cells, embryos were treated with an FGF receptor 1 inhibitor, SU5402, or an MEK inhibitor, U0126 during various embryonic stages. In the present study, it is shown that the embryos treated with SU5402 from the 16-cell stage to the early gastrula stage do not form pigment cells, whereas those treated after the early gastrula stage form pigment cells. In pigment cell formation, embryos suddenly exhibited the sensitivity to SU5402 only for 1 h at the neural plate stage(-4 h after the beginning of gastrulation). When U0126 treatment was carried out at various stages between the 8-cell and late neurula stages, the embryos scarcely formed pigment cells. Pigment cell formation occurred when the embryos were placed in U0126 at early tail bud stage. These results indicate that FGF signaling is involved in pigment cell formation at two separate processes during ascidian embryogenesis, whereas more prolonged period is required for MEK signaling.