• Journal of Ecology and Environment
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• 제31권4호
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• pp.255-260
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• 2008

A commonly held view in studies of character displacement is that character states of both species are shifted in areas of sympatry. This view has been confirmed in an overwhelming number of cases for ecological character displacement. Excluding species pairs in which one of the two interacting species is found only within the distribution of the other species and species displaying gynogenesis, the pattern of reproductive character displacement is asymmetrical in that the shift in character states between areas of symaptry and allopatry occurs in only one of the two interacting species. Hypotheses for the reasons behind this asymmetry in reproductive character displacement include (1) homogenization by gene flow, (2) other mechanisms of reproductive isolation, and (3) sufficient reproductive isolation being provided by one of the interacting species exhibiting a pattern of reproductive character displacement. Because reproductive isolation can be achieved by divergence at any point in a sequence of premating reproductive behaviors and postmating developments, it is necessary to understand the mechanisms of reproductive isolation of two interacting taxa in areas of sympatry and allopatry and to analyze the relative contributions of potential factors to reproductive isolation to disentangle hypotheses for the patterns of asymmetry.

• Animal cells and systems
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• 제4권2호
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• pp.109-115
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• 2000

To clarify taxonomic status of the two sibling species, Moroco oxycephalus and M. lagowskii reproductive isolation mechanisms were investigated at sympatric area located in Kansung-up, Kosung-gun, Kangwon-do, Korea. Genetic analysis was performed to reveal mating system and intensity of Hybridization between the two species. The frequencies of hybrids were increased since 1989, and then the observed hybrid frequencies ($H_O$) did not significantly differ from the expected hybrid ($H_E$) in 1998 and 1999. However, based on histological analysis of two parents and their hybrid s gonads, the hybridizations between M. oxycephalus and M. lagowskii produced mostly fertile females but sterile males in accordance with Haldane s rule. Although it was suspected that pre- and postmating isolation mechanisms were affected between the two species, M. oxycephalus and M. lagowskii seemed to be strongly isolated with microhabitat at sympatry until 1997. Since 1998, hybrid frequencies were increased by habitat disturbance. However, their hybrid frequencies would be reduced by postmating isolation mechanisms. Therefore, the two species are considered to be distinct species recently diverged.

• Clinical and Experimental Reproductive Medicine
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• 제10권1호
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• pp.25-37
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• 1983

A group of 180 men who visited Urology Department of Severance hospital, including 115 patients with nongonococcal urethritis (N.G.U.), 27 patients with prostatitis, 13 patients with gonococcal urethritis (G.U.) and 25 healthy medical student controls were investigated for the isolation of Ureaplasma urealyticum (T-strain mycoplasma) from the specimen of ureaplasma discharge, urine and semen. Taylor-Robinson media of T-broth and T-agar was used for the isolation of Ureaplasma urealyticum. To the best of our knowledge, the study on the culture of Ureaplasma urealy ticum was reported for the first time in Korea. The followis g results were obtained: 1. The isolation rate of Ureaplasma urealyticum in nongonococcal urethritis (53.0%) revealed highest of those in the other three groups of prostatitis, gonococcal urethritis and control (40.7%,38.4% and 16.0% respectively). 2. As for the specimens, urethral discharge revelaed higher isolation rate of Ureaplasma urealyticum (54.6%) than first voided urine (50.0%). 3. The more consorts patients had, the higher positive culture rate of Ureaplasma urealyticum were revealed. The isolation rate in case of more than one causal in nongonococcal urethritis (27.8%) revealed much higher than in case of marital only (5.2%), one regular (6.1%) and one causal 03.9%). 4. 2.6% of isolation rate of Ureaplasma urealyticum revealed in patients with nongonococcal urethritis who visited the clinic in later than 4 weeks after the symptoms developed. However, the isolation rate in patients who visited within 4 weeks revealed 50.3%. The lower isolation rate of Ureaplasma in the late treatment seekers might be probably due to the suppression effect against Ureaplama urealyticum from the possible previous self antibiotic treatment. 5. Attachment of Ureaplasma urealyticum mostly to the neck and head portion of the spermatozoa seemed to playa role to affect the motility of sperms.

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2006년도 The 5th Biannual Meeting of Pacific Rim Society for Fertility and Sterility
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• pp.170.1-170.1
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• 2006

• 유기물자원화
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• 제26권3호
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• pp.39-46
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• 2018

유기성 폐기물 처리를 위해 강원도 홍천과 충청도 영동에서 사육되고 있는 두 지렁이 집단의 생식력 차이, 생식적 격리 정도 및 CO I 유전자의 서열을 비교하였다. 두 집단의 생식력에 큰 차이가 없었으며, 두 집단 간에 생식적 격리도 전혀 이루어지지 않았다. CO I 유전자 염기 서열을 분석하여 두 집단의 종을 동정한 결과 붉은줄지렁이 또는 줄지렁이로 확인되었고, 두 집단의 유연관계가 매우 가까운 것으로 나타났다. 따라서 두 집단은 같은 지렁이 종임을 강력히 시사하였다.

• 대한생식의학회:학술대회논문집
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• 대한불임학회 제1차 연수강좌
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• pp.215-221
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• 2000

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2006년도 The 5th Biannual Meeting of Pacific Rim Society for Fertility and Sterility
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• pp.54-57
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• 2006

• 한국동물위생학회지
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• 제22권4호
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• pp.363-370
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• 1999

돼지 호흡기 생식기증 바이러스(porcine reproductive and respiratory syndrome virus: PRRSV) 감염이 의심되는 농장으로부터 수집된 혈청가검물 646개로부터 MARC-145 cell을 이용하여 PRRSV 분리를 시도한 바 MARC-145 세포단층상에 세포변성효과(cytopathic effects : CPE)를 나타내는 바이러스 36주를 분리하였다. 분리된 36주가 PRRSV인지 여부를 확인하기 위하여 PRRSV를 실험적으로 접종한 혈청을 이용하여 간접형광항체시험과 혈청중화시험을 실시한 결과 36주 모두가 PRRSV로 동정되었다. 혈청학적인 동정법과 더불어 reverse-transcription polymerase chain reaction을 이용하여 PRRSV open reading frame 5(ORF5)의 유전자를 증폭한 결과 선발된 6주 모두에서 80bp의 flanking sequencing를 포함하여 약 680bp의 ORF5의 유전자를 증폭할 수 있었다.

• 대한생식의학회:학술대회논문집
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• 대한생식의학회 2007년도 제53차 추계학술대회 초록집
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• pp.114-114
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• 2007

• 대한생식의학회:학술대회논문집
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• 대한불임학회 1999년도 제38차 추계 학술대회
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• pp.38-39
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• 1999