• Journal of Animal Science and Technology
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• v.52 no.2
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• pp.83-90
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• 2010

Hanwoo proven bulls have been selected since 1987 and consequently contributed to farmers for the improvement of beef cattle in Korea. The demand for the quality beef production as well as higher production efficiency was erupted after early 2000 as relatively cheap imported beef released. Therefore the pressure on the reformation of selection index for Hanwoo proven bulls have been piled up to furnish with Hanwoo's competitive. A total of 734 progeny test data were analyzed to select traits and their weights in the selection index to meet the beef market requirement. Regression analysis with stepwise selection method was used to select proper trait and its weight for selection index. A series of computer simulation was carried out to compare the currently using selection index with the alternate two selection indices proposed in this study. New selection index using standardized breeding values of Loin eye Muscle Area (LMA), Backfat Thickness (BFT) and Marbling Score (MS) with weight ratio 1:-1:6 was proposed. Results showed higher performance in improving MS and BFT gain by 22% and 31% still holding 86%~89% of genetic gain achieved by current index in Carcass Weight (CW) and LMA when new selection index was fitted. Because, new index has little consideration for production cost, further research should be performed to build selection index including cost and income simultaneously.

• Korean Journal of Animal Reproduction
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• v.19 no.1
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• pp.15-34
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• 1995

1970년말부터 뇌하수체 성선자극호르몬(gonadotropic hormone ; GTH)의 유전자 구조(FSH$\beta$, LH$\beta$ 및 공동의 $\alpha$쇄)가 다양한 종에서 밝혀지기 시작하였으나 이러한 유전자의 조직/세포 특이적 분비양식과 세포외 신호에 의한 조절양식은 정확히 밝혀져 있지 않다. 그러나 최근 들어 형질전환 맞추스 제작기법에 의해 $\alpha$쇄 유전자 상류에 세포특이적 발현을 조절하는 특이부위가 존재함이 보고됨을 시작, FSH$\beta$ 및 LH$\beta$쇄 유전자발현을 조절하는 특이부위 또한 가까운 시기내 발견되리라 기대된다. 한편, 성선자극 호르몬 방출호르몬(GnRH), 스테로이드 호르몬 및 여러 결합단백질과 같은 세포의 신호는 각기 다른 신호전달체계를 통하여 GTH유전자 발현을 일으킨다. 또한 뇌하수체에서도 그 존재가 확인된 전사인자들 (cFos, cJun)과 미지의 인자들은 상호간에 다양한 이량체를 형성하여 유전자 발현을 조절하는 각 특이부위에 결합함으로써 전사단계에서의 다양한 제어가 존재함이 밝혀지고 있으며 이러한 유전자상의 특이발현영역과 세포의 신호별 전사인자에 관한 연구는 번식에 있어 중요한 성선자극호르몬에 관한 분자수준의 조절기전을 밝혀내리라 기대되어진다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.2
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• pp.112-116
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• 1993

The experiment was carried out to investigate the influence of rhizome size and mulching materials on some agronomic characters and flower-head yield of Gingiber mioga ROSCOE. The larger the size of rhizome was, the more the number of leaves developed, and the higher the yield was. The most suitable rhizome size for planting was found to be from I2cm to 15cm. Rice straw and polyethylene film mulching materials increased the soil porosity and reduced change of the soil moisture content. The yield of flower-head was highest in the straw-mulching plot, indicating that straw would be the best mulching material for growth and yield of flower-head in Gingiber mioga ROSCE.

• Reproductive and Developmental Biology
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• v.28 no.3
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• pp.203-207
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• 2004

The transgenic mice carrying human Interleukin-10 (hIL-10) gene in conjunction with bovine (3 -casein promoter express hIL-10 in milk during lactation. In this study, stability of germ line transmission and expression of hIL-10 transgene integrated into host chromosome were monitored up to generation F8 of transgenic mice. When male mouse of generation F8 was crossbred with normal females, approximately half of offspring (50.9±5.8%) were identified as transgenic mice. Generation F9 to F15 mice also showed similar transmission rates (66.0±20.1%, 61.5±16.7%, 41.1±8.4%, 40.7±20.3%, 61.3±10.8%, 49.2±18.8% and 43.8±25.9%, respectively), implying that hIL-10 transgene can be transmitted stably up to long term generation in the transgenic mice. Expression levels of human IL-10 from milk of generation F9 to F14 mice were 3.6± 1.2 mg/ml, 4.2±0.9 mg/ml, 5.7±1.5 mg/ml, 6.3±3.5 mg/ml, 6.8±4.5 mg/ml and 6.8±3.1 mg/ml, respectively, which was showed high-level expression compared with that of generation F1 (1.6 mg/ml) mice. In conclusion, our results suggest that transgenic mice can be continuously passed their transgenes to the progeny through the breeding program with the same productivity of human IL-10 protein in their milk.

• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.55-61
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• 1985

This study was carried out to investigate reproductive traits and sex hormone levels by growth in Korean native goats. Serum levels of FSH, LH, prolactin, estradiol-$17{\beta}$ and progesterone were determined every 15 days from the 70 days of age to 190 days by radioimmunoassay. The age and weight at sexual maturity were 183.6 days and 14.3 kg; the length of estrous cycle and estrus period were 20.3 days and 36.7 hours, respectively. The gestation period, litter size and body weight at birth were 148.4 days, 1.4 head and 1.8 kg, respectively. The levels of serum LH were highest with 3.93 mIU/ml at 70 days of age, thereafter decreased gradually to 1.21 mIU/ml at 190 days of age. The concentrations of FSH in serum were below 1.25 mIU/ml throughout the experimental period. The levels of prolactin were lowest with 3.09ng/ml at 85 days of age and highest with 4.65 ng/ml at 175 days of age. The serum levels of estradiol-$17{\beta}$ were increased with age, thus highest with 7.95 pg/ml at 190 days of age. The serum progesterone concentrations were maintained low levels (below 1.0 ng/ml) throughout the experimental period.

• Korean Journal of Animal Reproduction
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• v.19 no.1
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• pp.35-41
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• 1995

In this study, we have tested whether the retrovirus vector system is applicable in transgenic cattle production. To overcome low infectivity of currently available retrovirus vector system we have directly microinjected retrovirus-producing cells into the perivitelline space of the day 1.5 embryos. The virus-producing cell line was designed to release replication-defective retrovirus encapsidated with Gibbon ape leukemia virus (GaLV) envelope protein. E. coli LacZ gene was used as a marker gene to facilitate evaluation of the transgene expression and X-gal staining at morula or blastocyst stage resulted in expression of E. coli LacZ gene The results in these experiments were summarized as follows : 1. The lowest concentration of polybrene necessary for efficient virus infection was Sf' g/ml. 2. Development rate from day 1.5 embryos microinjected with virus-producing cells to the morulae /blastocysts was 29%. 3. 21% of the morulae /blastocysts were LacZ+. 4. There was no evidence that the retrovirus-producing cells used in this study produced replication-competent retrovirus.

• Korean Journal of Animal Reproduction
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• v.20 no.1
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• pp.43-52
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• 1996

This study was carried out to establish the in vitro short-term culture system of developing male germ cells by purifing germ cells of various stages. The decapulated testicular cells were incubated with collagenase (lmg/ml) and try psin (2.5mg/ml) in HBSS. After separating male germ cell, the separated germ cells were stained with heamatoxylin/eosin and determined developing stages under light microscopy. The purity of pachtene spermatocytes a and round spermatid were 85%, respectively. Yield of total male germ cells was highly variable between individuals, with a mean value of 3.5 to 4.5 ${\times}$ 10$^7$ cells/testis. Viability of the cell was over 97% after separation. In DMEM medium, the optimal cell number for culture is approximately 1 x 10$^5$ cells/dish, but low cell den-sities than 1 ${\times}$ 10$^5$ cell/dish showed a decreased cell viability. Furthermore, about :36.8% of pac-hytene cells was successfully cultured for 6 days and some of cells were developed to secondary spermatids and round spermatids. Therefore, our data suggested that this culture conditions will be utilize as a feasible tools to produce tran-sgenic livestock using techniques such as intrac-ytoplasmic injection and cell fusion.

• Korean Journal of Animal Reproduction
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• v.25 no.2
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• pp.171-180
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• 2001

Compared to other gene transfer system, the advantages of retrovirus-mediated gene transfer are technical ease, efficient expression and genetic stability. Despite the high potency of the retrovirus vector system in gene transfer, one of the drawbacks is a difficulty in concentration of virus stock. To overcome this problem, we tested a new retrovirus vector system producing the progeny retrovirus particles encapsidated with VSV-G (vesicular stomatitis virus G glycoprotein). The infectivity of this virus was not sacrificed by ultracentrifugal concentration and the host cell range extended from all mammalian to fish embryos. Virus titer after 1,000 x concentration was more than 10$^{8}$ CFU/ $m\ell$ on most of the target cell lines. We applied this pantropic viruses in transgenic chicken production by injecting the concentrated (100$\times$) stock into subgerminal cavity of stage X chicken embryos. The survival rate of chicken embryos after injection was about 20% and gene integration rate in surviving embryos was scored almost 100%. Analyses of RT-PCR and fluorescence microscopy, however, showed no evidence of the transgene expression.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.324-327
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• 2009

The white flowered 'Eorayeon 1ho' is the first Kangwon National University cultivar of L. ${\times}$ formolonga, commonly known as seed propagating lily. Crosses were conducted from 1999 to 2003 among the selected selfing lines($S_3$) of L. longiflorum 'Lorina', L. ${\times}$ formolonga 'Augusta' and 'Raizan Herald'. A new cultivar was preliminarily selected as 'E-No.1' in 2003 for its stable upward flowering habit. The evaluation of characteristics was investigated from 2003 to 2004 in Chuncheon and Yungweol, Kangwon province. 'Eorayeon 1ho' blooms in early July at outside, with high resistance to Botrytis and having upward flowering habit. The plant height is 112.4 cm and the percentage of seed germination is 96.4%. This seed propagating cultivar shows good quality as a cut flower and low blasting rate.

• Korean Journal of Plant Resources
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• v.9 no.1
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• pp.71-75
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• 1996

Experiments were conducted to investigate the proper stem number and the propagation method of Lycium Chinense Mill. from 1993 to 1994.The results obtained were summerized as follows. The most effective propagation method was stem cutting 20cm in which flowering time was 15days earlier and dry fruit weight was 30 percent heavier(91kg/10a) than in seed propagation. The optimal diameter of cutting was 0.9cm of which dry fruit weight was 227kg/10a and 28 percent heavier compared with that of 0.5cm. stem number 5 had the best top growth and the heaviest 100 fruit weight as 13.4g. Fruit number per plant was increased as 864 in stem number 5. Dry fruit yield of stem number 5 was 104kg/10a and 16 percent increased compared with that of control.