• Applied Microscopy
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• 제46권1호
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• pp.58-66
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• 2016

Thymosin ${\beta}4$ ($T{\beta}4$) has been recently reported to play a role in dentinogenesis by regulating the expression of dentin matrix proteins. Based on previous studies, it is hypothesized that $T{\beta}4$ is associated with the formation of the enamel matrix and thus plays an important role in ameloblast. However, there is no report on the function of $T{\beta}4$ during tooth development so far. Therefore, in this study, we aimed to investigate the expression of $T{\beta}4$ and its function in ameloblasts during mouse tooth development. $T{\beta}4$ was expressed strongly in the tooth bud at the bud stage and in the dental lamina and oral epithelium at the cap stage. In advanced bell stage at postnatal day 4, large elongated ameloblasts were observed and the expression of the $T{\beta}4$ protein was the highest, with the enamel being was thicker than that in the early bell stage. The length of ameloblasts increased from the presecretory to the secretory stage and decreased from the maturation to the protective stage. These results suggest that $T{\beta}4$ participates not only in the proliferation of oral epithelial cells during the early stage of tooth development but also regulates enamel protein secretion in ameloblasts and enamel mineralization.

• 한국자원식물학회지
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• 제17권1호
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• pp.28-33
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• 2004

본 연구는 개량 포플러 현사시 3호를 재료로 제초제 저항성 유전자 PAT으로 형질전환시 킨 다음 제초제 Basta처리에 의한 효율적인 형질전환체 선발을 목적으로 시험되었다. Basta 처리에 따른 캘러스유도, 부정아유도 및 액아유도 시험을 통해 조직치사 농도는 1.0mg/L로 결정할 수 있었으며, 이 농도처리에 의해 형질전환체의 조기선발에 사용하였다. 이 농도처리로 비형질전환체는 모두 고사되었지만, 형질전환체는 정상적으로 반응을 보이며, 생육이 가능하였다 .한편, 형질전환체에 제초제를 직접 살포한 결과, 정상적 생육이 가능했고, PAT activity측정 결과에서도 양성 반응을 나타내어 현사시 3호 세포내에 PAT유전자가 정상 발현됨이 확인되었다. 이로써 현사시에 PAT유전자 도입 및 발현을 위하여 제초제 Basta 처 리와 PAT assay가 매우 효과적인 것으로 나타났다.

• 한국약용작물학회지
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• 제14권1호
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• pp.23-26
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• 2006

기관배양을 통한 대량증식 방법의 일환으로 액아배양을 이용한 multiple shoot 유도 조건을 조사하였다. 기내 배양 중인 식물체로부터 액아를 절취하여 TDZ와 BA를 각각 농도 별로 첨가한 MS배지와 1/2 MS배지에서 6주간 배양한 결과, MS기본배지에 $0.005\;mg{\cdot}L^{-1}$ TDZ가 첨가된 처리구에서 효과가 가장 양호하였다. 한편 발생된 신초를 $1\;mg{\cdot}L^{-1}\;GA_3$와 $0.5\;mg{\cdot}L^{-1}$ IBA가 첨가된 1/2 MS배지에 배양했을 때 뿌리의 발생과 신장이 가장 양호하였다. 발근된 식물체를 포트에서 순화시켜 온실로 이식하였을 때 90%에 가까운 생존율을 보였으며 형태적인 변이 없이 생장하였다. 이상의 결과는 액아유도를 통한 대량번식의 가능성을 제시한다.

• 식물조직배양학회지
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• 제21권5호
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• pp.277-280
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• 1994

생장점배양하여 얻어진 소수의 식물체를 기내 재배양하여 건전 우량마늘을 대량으로 증식시킬 수 있었다. MS 기본배지에 서당 8%, NAA 0.1 mg.L 첨가된 배지에 지엽을 뚫고 나온 직후의 주아 생장점을 5월 중순에 치상하면 shoot의 형성 없이 기내인경이 직접 형성되어 배양 기간 및 노력을 절약할 수 있었다. 또한 총포 내의 미숙주아 및 receptacle을 6월 상순경에 0.1 mg/L NAA+2mg/L BA 혹은 1 mg/L NAA + 10 mg/L BA가 첨가된 MS 기본배지에 배양하면 multiple shoot가 유도되었다. 특히 여러 화기 재료중 receptacle에서 평균 5.8개의 shoot가 분화되어 1개의 총포 내에서 50개 이상 분화되었다. 따라서 총포배양에 의한 식물체 생산은 우량마늘의 대량번식 체계의 한 수단으로 이용할 수 있었다.

• 한국작물학회지
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• 제27권2호
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• pp.111-115
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• 1982

속간교잡을 실시함에 있어서 교배방법 및 교배촉진 물질로 알려진 EACA와 $GA_3$의 처리가 결실율 향상에 미치는 영향을 구명하고 교배시기에 있어서 뢰수분과 노화수분중 어떤 처리가 교잡종 생산에 유리한가를 검토하여 생장조절제인 EACA와 $GA_3$를 함께 처리한 구와 EACA만을 처리한 구를 두고 생장조절제의 효과도 아울러 구명코저 시험한 바 그 결과를 요약하면 다음과 같다. 1. 대맥$\times$소맥 속간교잡을 실시할 때는 노화수분의 결실율(4.5%)이 뢰수분보다 훨씬 높았다. 그러나 배형성율은 오히려 뢰수분쪽이 높았다. 2. $GA_3$ 처리 효과는 크게 인정되었으나 EACA 단독 효과는 인정되지 않았다. 3. 대맥$\times$소맥을 속간교잡하여 2개체의 형태적으로 소맥쪽을 더 닮은 식물체를 얻었으며 이는 생육이 진행될수록 더욱 소맥과 유사하였다. 이밖에도 시험관내에서 얼마간 자란 9개의 식물체도 얻을 수 있었다.

• 한국약용작물학회지
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• 제10권4호
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• pp.249-252
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• 2002

Several plant growth regulators were examined for on their effect on the in vitro propagation of Kalopanax pictus$(T_{HUNB}.)$ $(N_{AKAI}.)$ on WPM medium. Among the cytokinins tested, BA at $13.32\;{\mu}M$ appeared to be the most effective for multiple axillary shoot formation. Although the addition of $2.89\;{\mu}M\;GA_3$ promoted stem elongation, it produced morphologically abnormal leaves and stems. For rooting of the shoots, $4.9\;{\mu}M$ IBA seemed to be more effective than $2.69\;{\mu}M$ NAA. When the regenerated plants were transferred on artificial mixture containing vermiculite and peat-moss (1 : 1, v/v), 81% of them survived and grew normally.

• Asian-Australasian Journal of Animal Sciences
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• 제1권1호
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• pp.43-46
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• 1988

Based on our previous results that among 4 strains of mice SHN and GR/A showed the highest mammary growth potentials in females and males, respectively. Effects of crossbreeding on normal and neoplastic mammary growth were studied in $(SHN\;{\times}\;GR/A)F_1$ virgin female mice. $F_1$ mice were higher than the parental strains in the end-bud formation and the ductal growth of mammary glands at 60 days of age and at tumorous age, respectively. While there was little difference between $F_1$ and both parental strains in the onset age of the first mammary tumors, mammary tumorigenic potential was apparently higher in the former than in the latters. This would be the first report that demonstrated directly the contribution of mammary growth potential of males to that of female offspring.

• Journal of Microbiology
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• 제34권3호
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• pp.248-254
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• 1996

$cdc103^+$ gene in Schizosaccharomyces pombe which is similar to the CDC3 gene in Saccharomyces cerevisiae was cloned and sequenced. Comparison of the predicted amino acid sequences of $cdc103^+$ and CDC3 revealed that they share significant similarity (43% identity and 56% identity or similarity) to each other. The gene product of CDC3 in S. cerevisiae is known to be a highly ordered ring of filaments that lies just inside the cytoplasmic membrane in the region of the mother-bud neck. In order to characterize the gene product of $cdc103^+$ in Schizosaccharomyces pombe, fusion proteins were used to generate the polyclonal antibodies specific for the gene product (cdc103p). In immunofluorescence experiments, these antibodies decorate the region of the septum formation as a double ring structure late in the cell division cycle.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.214-214
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• 2013

Ion beam sputtering (IBS) by collision of energetic ions at surfaces is one of the representative methods for physical self-assembly. It is in spotlight as an easy tool to make nano structures in various sizes and shapes by controlling physical variablesWe investigate nano patterning on graphite. We found well-ordered nano ripple patterns after sputtering under the oblique angle and mean wavelengths of these ripples could be controlled as ion fluence increases from sub-10 nm to 80 nm. Each nano ripple is terminated by nano buds, which look like a cotton bud. We also examined the formation of various patterns on graphite by sputtering during swinging the sample at a constant angular velocity that have been never reported.

• 아시안잔디학회지
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• 제1권1호
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• pp.42-48
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• 1987

This study was carried out to elucidate the physiological and ecological mechamism of the branch pattern and electronmicroscopic structure of photosynthetic organs in Zoysia japonica Steud. The angles between the internodes of rhizome and the branches of Z.iaponica were changed from 0 to 52 degrees. The rhizomes tended to branch from the 3th node to the 10th node. When the terminal bud was damaged by various environmental factors, the initial branching formation was appeared immediately to the 4th node. The internode growth of the rhizome started from the beginning of April and continued to the end of Octobor. It became evident that there is a division labor between two different kinds of photosynthetic cells of mesophyll and bundle sheath tissues in Z.japonica The thick-walled bundle sheath cells surrounds the leaf vascular bundles as the Kranz type and separates them from the mesophyll cells.