• Radiation Oncology Journal
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• v.11 no.1
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• pp.43-50
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• 1993

We evaluated frequency and types of chromosomal aberrations by ionizing radiation in cancer patients treated with radiotherapy in our institution. Twenty-five patients with various types of carcinomas such as lung, uterine cervix, esophagus, rectum, head and neck and pancreatic cancers were studied immediately before and after external beam radiotherapy. The frequency of aberrant metaphase prior to treatment was $4.93{\%}$, which was higher than that of control group. Especially in lung cancer, the freuqency of aberrant metaphase was three times higher than control group. A comparison of chromosomal abnormalities observed before and after radiotherapy demonstrated that proportion of aberrant rnetaphases was significantly inreased to $22.13{\%}$. Major chromosomal aberrations like structural abnormalities showed remarkalbe increase from 65.45 to $88.45{\%}$ after the treatment. Also the numbers of chromosomal alterations per cell were increased by a factor of 6.5. Aberrations with two or more break points were more prominently increased, compared with aberrations with single break point. The number of chromosomal break points was noted to be higher than expected value in No.1, 3, 8 and 11 chromosomes and lower in No.13, 15, 17 and 21 chromosomes. Based on this study, we believe that the distribution of chromosomal breakage is related with gene and chromosomal rearrangement which could result in the development of cancers.

• Journal of Life Science
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• v.15 no.2 s.69
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• pp.176-181
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• 2005

To study calmodulin (CaM) gene expression and its regulation, rice CaM promoter (RCaM-2) was isolated and fused to $\beta-glucuronidase$ (GUS), reporter gene. X-Glue staining patterns revealed that GUS localization is high in meristemic tissues such as the stem apex, stolen tip, and vascular regions. GUS staining in the transverse sections of stem and petiole was restricted to the inside of the vascular system, and cortex and epidermis located outside of the vascular system usually did not show GUS staining even a plant that expressed strong activity. GUS activity was found to be tissue specific expressed and exhibited a dramatic transient increase in response to wounding. These results suggest that the 5'-flanking region of RCaM gene regulates wound-inducible expression.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.110.1-110.1
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• 2011

오리온 A 분자운은 별탄생이 활발하게 일어나는 영역이다. 때문에 분자운 연구를 통해서 별탄생을 연구하기에는 최적의 곳이다. 특기할 것은 Orion A에는 필라멘트 구조가 있다는 점이다. 필라멘트는 전형적으로는 길이 4.8pc, 너비 1.4 pc 로 제시되었다(Nagahama et al. 1998). 많은 미지의 조건들 가운데 필라멘트 구조는 별탄생에 대한 새로운 조명을 던져주는 데, 가령 분자운이 수축, 분열하며 작은 덩어리를 만드는 과정에 이런 기다란 구조가 별탄생에 어떤 과정에서 나타나며 이것이 별탄생이 어떤 효과를 발생하는지 연구되어야 하는 문제들이다. 대덕전파안테나의 1분의 분해능(Channel resolution 63 KHz/ Band Width 25 MHz) 의 12CO, 13CO(J=1-0) 분자선 관측으로 필라멘트를 이전 연구보다 자세하게 관측하여 이것 안에 있을 것으로 보이는 substructure들 연구하고자 한다. 관측영역은 적경: 5h 32m ~ 5h 37m, 적위: $-5^{\circ}$ 14' ~ $-5^{\circ}$ 37'으로 ($1^{\circ}{\times}1^{\circ}$) 영역을 관측하였다. 그 결과 필라멘트구조를 확인할 수 있었으며 약 0.7pc,약 $1000\;M_{\odot}$의 덩어리들이 이전관측에서 보여진 X자형태가 아니라 일자형태로 분포되어있는 것을 알 수 있었다. 관측된 최소덩어리는 star cluster mass이고 stellar size 의 덩어리는 별탄생 과정 이후 소멸된 것으로 보인다. 관측으로 확인된 덩어리들의 물리적인 성질과 분포를 깊이 연구해 보고자 한다. 향후 Orion A 전체를 추가로 관측하고자 한다.

• Journal of ILASS-Korea
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• v.16 no.3
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• pp.140-145
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• 2011

Gelled propellants are non-Newtonian fluids in which the viscosity is a function of the shear rate, and they have a high dynamic shear viscosity which depends on the amount of gelling agent contents. The present study has focused on the breakup process, wave development of ligament and liquid sheets formed by impinging jets with various gelling agent contents. The breakup process of like-on-like doublet impinging jets are experimentally characterized using non-Newtonian liquids. The spray shape with elliptical pattern is distributed in a perpendicular direction to the momentum vectors of the jets. Gelled propellant simulants with high viscosity jets are more stable and produce less pronounced surface waves than low viscosity jets. Gelled propellant simulants from like-on-like doublet impinging jets have the spray shape of closed rim patterns at low pressure. As the injection pressure increased, rimless patterns which were composed of ligament sheets and small droplets emerged due to the effect of the aerodynamic action.

• Korean Journal of Plant Tissue Culture
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• v.21 no.5
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• pp.299-302
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• 1994

Immature zygotic embryos (up to 4mm in length) were cultured on MS medium supplemented with 0.5 to 8mg/L 2,4-D. Up to 87% of them formed somatic embryos on the plumule without producing an intervening callus. The site of somatic embryo formation was confirmed by culturing plumule explants, which consisted of shoot apical meristem domes with 1 or 2 leaf primordia excised from 2-week-old seedlings. When the concentration of 2,4-D was increased over 4 mg/L, the plumule explants produced nonembryogenic calli only, whereas the distal end of the cotyledons directly formed numerous somatic embryos at frequencies of up to 60%. Upon transfer onto MS basal medium,2 out of 15 somatic embryos converted into plantlets. The plantlets were potted to a soil mixture and grown to maturity in a phytotron.

• The Korean Journal of Cytopathology
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• v.9 no.1
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• pp.105-110
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• 1998

Adenomyoepithelioma is an uncommon benign tumor of the breast. We present the fine needle aspiration cytologic features of adenomyoepithelioma in a 23 year-old Korean women, initially diagnosed as fibroadenoma. Aspiration cytologic findings of the left breast mass revealed high cellularity, small to medium sized, less cohesive epithelial clusters, rich naked cells and amorphous materials on background. The epithelial cells were round and uniform with no cytologic atypia or mitosis. Myoeplthelial cells were conspicuous with peripheral rimming along the epithelial clusters. Small amount of fibrotic stromal tissues were observed. Distinguishing features from typical fibroadenoma are less tight epithelial clusters, dyscohesive epithelial cell aggregates, more abundant naked cells and scant stromal tissue fragments.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.1
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• pp.48-54
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• 1987

To search for the optimal nitrogen application method for the machine transplanting to Dongjinbyeo, compared to conventional method, in the various methods of nitrogen split application at different growth stages of rice plant. This experiment was performed at Honam Crop Experiment Station, in 1985 year. The results were as followed; the nitrogen contents of leaf blade was the highest at maximum tillering stage under the conventional method and reduction division stage under the nitrogen top-dressing at panicle initiation and 5 times split application of nitrogen for the whole rice growth stages. CGR, RGR and NAR after heading was highest under 5 times split application of nitrogen for the whole rice growth stages. Relationships between CGR and NAR, NAR and RGR, CGR and RGR showed the positive correlation significantly at each rice growth stage, respectively, and showed more high correlation according to further rice growth stages. The degree of contribution of CGR to rice grain yield was the highest at 20 days after heading. Rice grail: yield was higher under top-dressing of nitrogen at panicle initiation and basal application (30%) + 4 times equal dispensing top-dressing after basal application of nitrogen than conventional method.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.399-405
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• 2020

The objective of this study was to identify the effect of zebularine soaking on the early growth stage of barley (Hordeum vulgare L.). Hence, root elongation was measured daily according to the different concentrations of zebularine (1.0, 2.5, 5.0, and 10.0 μM) for 4 days. On the first day, root length at 2.5 and 5.0 μM was significantly longer than that in the non-treated control. On the second day, root length was not significantly different among all concentrations and controls. On the third day, root elongation was suppressed by the effect of zebularine, except at 2.5 μM. The treatment time of zebularine accounted for the largest proportion of the variation in root elongation. After transplanting, plant growth velocity was similar to that of the control; however, plants at 2.5 μM showed faster growth velocity than that of the other concentrations and the control. In the metaphase of mitosis, most chromosomes of cells under zebularine treatment were ordinary regardless of the concentration, while some cells with short chromosomes were investigated at around 2%. The short chromosome showed a centromere. In addition, it showed short and long arms based on the centromere. The lengths of the short and long arms were different for each short chromosome. It is necessary to study the effect of the short chromosome as a chromosomal function on plant growth and phenotype through investigation of meiosis and fertilization at the chromosome level.

• Korean Journal of Biological Psychiatry
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• v.11 no.2
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• pp.127-135
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• 2004

Object:The goal of this study was to examine the changes in body weight and glucose levels of the patients treated with risperidone, clozapine or haloperidol in order to compare the effect of risperidone or clozapine with that of haloperidol. Methods:For nine months(January to September, 2003), a prospective study was performed in 60 patients with chronic schizophrenia who were in Seoul National Hospital. Two-week period was required for a drug wash-out. The patients were randomly assigned to risperidone, clozapine and haloperidol groups. They were given risperidone(n=20), clozapine(n=20) and haloperidol(n=20), respectively, everyday for 12 weeks. To examine the effects of these drugs on body weight and fasting glucose levels, we measured body weight and glucose levels of all the patients first without the drug treatment and at each end of 4, 8, and 12-week periods with the treatment. And we examined the differences among three groups in the changes of body weight and fasting glucose levels. Results:There were no significant differences in the changes of the body weight and fasting glucose levels between the atypical antipsychotics(risperidone or clozapine) and the typical antipsychotics(haloperidol). Conclusion:The study in the patients with chronic schizophrenia suggests that risperidone or clozapine do not cause any additional effects on body weight or glucose levels compared to haloperidol.

• Korean Journal of Plant Taxonomy
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• v.40 no.4
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• pp.226-233
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• 2010

An intensive study of the embryology of Gymnospermium microrrhynchum was conducted to provide information regarding a discussion of the phylogenetic relationships of the genus, which is yet unstudied. Our results indicated that Gymnospermium is similar to other genera of Berberidaceae in terms of its embryological features. Nevertheless, newly reported and unique features are the well-developed endothelium and the undifferentiated seed coat type. Until the study of Gymnospermium, it may have been considered to be closer to Caulophyllum and Leontice in the tribe Leonticeae. These three genera share many morphological features as well as molecular similarities, by which they are kept in the same tribe, Leonticeae. However, very little detailed embryological data regarding these genera have been published thus far. Gymnospermium was characterized according to the basic type of anther wall formation as well as its glandular tapetum, successive cytokinesis in the microspore mother cell, two-celled mature pollen grains, anatropous and crassinucellate ovules with a nucellar cap, well-developed endothelium, its Polygonum type of embryo sac formation, its nuclear type of endosperm formation, and its undifferentiated seed coat type. In comparison with Nandina, there are many differences, such as the dehiscence of the anther, the cytokinesis in the microspore mother cells, the shape of the megaspore dyad, and the seed characteristics. Although we had no available detailed embryological information regarding Caulophyllum and Leontice, which are genera that are more closely related to Gymnospermium, we could deduce from the phylogenetic relationship that Gymnospermium, Caulophyllum, and Leontice are more closely related to each other than other genera of Berberidaceae on the basis of the seed characteristics.