• The Korean Journal of Zoology
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• v.11 no.2
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• pp.72-74
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• 1968

X-線이 초파리의 第三齡幼　에 1,500r의 X-線을 照射하여 어버이와 그자손의 産卵能力, 羽化數 및, 羽化率에 미치는 영향을 考察하였다. 1. 어버이代에서는 處理區가 對照區에 比하여 훨씬 낮은 産卵數를 보였으나 處理區사이에는 差異가 없었다. 2. 자손에 이르면 産卵能力이 어버이代보다 약 85% 增加되는데 자손代에서 2次로 X-線照射를 받으면 어버이代가 보여준 産卵能力과 비슷해 진다. 3. 羽化數와 羽化率은 어버이代에서는 물론 자손代에 서도 各處理區間에 差異를 보인다. 4. 어버이代와 자손代가 모두 照射를 받았을 때, 그 영향이 産卵能力에는 加重되어 나타나지 않으나 羽化率을 분석하면 加重현상이 나타난다. 5. X-線에 依한 傷害로 부터의 回復期는 成體에 比하여 幼　이 더 길었다.

• Journal of Aquaculture
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• v.13 no.4
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• pp.325-330
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• 2000

For development of all male seed production at hatchery scale, a comparative study was made on the seed production traits of supermale (IT - t) and superfemale (IT - L1 ~) Nile tilapia, Oreochromis niloticus. Supermales were crossed with normal females (XX- f) and the superfemales with normal males (XY - t ) or sex reversed males (XX- L1 t); progeny survival of these crossings and sex ratio were evaluated. Hatching success of the eggs, fertilized by the supermale was significantly lower than that by the normal male. Over 95-99 % progenies sired by crossing supermales with normal females were males, while 52-55 % progenies alone were males with the cross of normal males and normal females. Hatching success and survival of alevins were significantly higher for the progenies of the crosses between superfemales and sex reversed males than those resulting from the crosses between superfemales and normal males. However, there was no significant difference in the sex ratio among the progenies of these crosses. Therefore, crossings of superfemales with sex reversed males provide the highest percentage of survival and male progenies.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.67-68
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• 2003

라돈은 일반적으로 가장 잘 알려진 천연 방사성핵종 중 하나로서 무향 무색의 불활성기체이며 붕괴과정에서 알파입자를 방출한다. 라돈에 의한 피폭선량은 라돈붕괴에 의해 생성된 라돈자손이 호흡기관 표면에 침착되어 방출하는 알파선에 기인한다. 따라서, 피폭선량에 주로 기인하는 것은 라돈 자신이 아니라 그의 단 반감기 라돈자손들이다. 이처럼 라돈은 잘 알려진 폐암 유발원으로서 고농도의 라돈에 장기간 노출되는 경우 폐암을 유발할 수 있다. UNSCEAR 보고서(1993)는 자연 환경중에서 인간이 받는 연간 총 피폭선량인 2.4 mSv중 약 50%에 해당하는 1.15 mSv가 라돈과 그 자손에 의한 것이며 대부분 옥내에서의 호흡에 의해 비롯된다고 평가하고 있다. (중략)

• Korean Journal of Poultry Science
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• v.41 no.3
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• pp.217-225
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• 2014

Telomeres are the ends of the eukaryotic chromosomes and consist of a tandem repetitive DNA sequence and shelterin protein complex. The function of telomere is to protect chromosome. Telomere length in somatic cells tends to decrease with organismal age due to the end replication problem. However, several factors at the genetic, epigenetic and environmental level affect telomere length. In this study, we estimated heritability of telomere length and investigated inheritance of telomeres in a chicken. Telomere length of lymphocytes was analyzed by semi-quantitative polymerase chain reaction using telomere primer and quantitative fluorescence in situ hybridization using telomeric DNA probe. In results, heritability of telomere length was estimated 0.9 at birth by offspring-parent regression analysis and was estimated 0.03 and 0.04 at 10 and 30 weeks old, respectively, by parental variance analysis. There was a significant positive correlation in telomere length between father and their offspring (r=0.348), and mother and their offspring (r=0.380). In inheritance patterns of telomere length, the influence of paternal and maternal effect on their offspring was similar. The influence of inherited telomeres on male and female progeny was also roughly alike. These results implicated that imprinting of parental telomere length was regulated by autosomal genes, not sex linked genes. In addition, telomere length of offspring at birth did not differ along with their maternal age. Thus, maternal age does not affects telomere length in their offspring at birth owing to cellular reprogramming at early embryonic stage.

• Journal of Aquaculture
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• v.13 no.4
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• pp.331-338
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• 2000

To establish an alternate technology for all male seed production of Nile tilapia, Oreochromis niloticus at hatchery scale, the performance of progenies produced by crossing superfemale with sex reversed male was evaluated. Free crossings between 21 superfemales and 7 sex reversed males stocked in an aquarium for 60 days resulted in the production of 93.5 % male progenies, compared to 53.2 % males produced by an equal number of normal females and normal males. Spawning frequency was lower (19 times) in the experimental cross including superfemales than that (24 times) in the control including normal females. Seed production in the experimental aquarium was (3,085) significantly lower than that (3,797) of the control. Both in terms of seeds per female per day or seeds per g female per day, seed productivity did not significantly differ between these groups. The alternate technology involving crossing between superfemale and sex reversed male has proven to be an efficient alternate technology for mass production of all male seeds at the hatchery scale.

• 방재와보험
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• s.59
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• pp.20-21
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• 1993

• KOREAN POULTRY JOURNAL
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• v.20 no.5 s.223
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• pp.116-119
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• 1988

우리 민족은 누구나 농부의 자손이며 흙과 더불어 성장해왔음을 간과해서는 안된다.

• KOREAN POULTRY JOURNAL
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• v.37 no.1 s.423
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• pp.62-64
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• 2005

• Journal of Aquaculture
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• v.9 no.1
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• pp.101-106
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• 1996

Gynogenetic males induced from sex reversed female (${\Delta}XY$) were crossed with normal female (XX) for analysing their genotypes. The fish tested produced a high percentage of male progenies (93.3 to $100\%$) and were considered as supermales (YY). Superfemales (${\Delta}YY$) were also produced by combination of sex reversal and chromosome manipulation techniques. Superfemale fish can be produced approximetly $90\%$ of male when the fish were crossed with normal male. Chi-square values against an expected 1 : 1 (male : female) ratio were highly significant for both YY males${\times}$ normal females (P<0.01 or P<0.001) and ${\Delta}YY$ females${\times}$normal males (P<0.005 or P<0.001). All male progenies were produced consistently when crossed supermales (YY) with superfemales (${\Delta}YY$).

• FLOWER RESEARCH JOURNAL
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• v.19 no.4
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• pp.231-237
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• 2011

In this study, we performed ovule culture after reciprocal crosses of two Alstroemeria accessions and investigated genetic contribution of parents by using RAPD markers. The best method was half-ovule culture on MS medium supplemented with $60g{\cdot}L^{-1}$ sucrose and $2.2g{\cdot}L^{-1}$ gelrite at 14 days after pollination. Embryos began to germinate after 6 weeks of culture. The complete plantlets were formed after 4 months of culture. In eight progenies and two parental cultivars, 59 polymorphic bands were obtained out of 89 total bands by RAPD analysis using 7 primers. Eight $F_1$ progenies from the crosses between two accessions using reciprocal crosses showed 1:1 contribution of maternal and paternal parents. It is confirmed that $F_1$ progenies were obtained from parental accessions by using RAPD markers. We conclude this cross combination showed pre-fertilization barriers with incompatibility between stigma or style, and pollen because progeny number was different in each cross combination. Thereby, it warrants overcoming pre-fertilization barrier together with post-fertilization barrier in order to broaden the heterozygosity within progeny populations in Alstroemeria breeding program.