• Applied Microscopy
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• 제30권2호
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• pp.205-212
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• 2000

Present study was performed to observe the surface ultrastructures of Stictadora furcatum (Trematoda: Heterophyidae). Adult worms were recovered from the cat experimentally infected with metacercariae, and were prepared for scanning electron microscopy. The body was leaf-like and ventrally concave. The oral sucker armed with prominent tegumental spines on the inner surface, and it's lips were obscure. Sensory papillae (type I) in single or grouped forms symmetrically arranged around the oral sucker. The ventrogenital opening retained protruding gonotyl spines and sperms discharged from the genital pore . The body surface was covered with scale-like multipointed tegumental spines. The density and digitated point of spines were gradually decreased toward the posterior end of the body. The digitated points of spines on the anterior portion were 9-12, on the middle were 7-8 and 5-6, and on the posterior were 2-3 and peg-like. Although the tegumental ultrastructure of S. fuscatum was generally similar to those of other heterophyid flukes , the oral sucker with tegumental spines on the inner surface and without obvious lips, and the ventrogenital opening with protruding gonotyl spines were suggested to be the characteristic features.

• 한국잠사곤충학회지
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• 제7권
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• pp.39-42
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• 1967

가잠이중교배에 있어서 차대잠산란순서를 조사한 바 다음과 같은 결과를 얻었다. 1. 교배순서에 의하여 양웅성 잠품종의 수정란이 순서적으로 산란하는 것이 아니고 초산란구에 제 2차교미 잠품종의 수정란이 도의와는 반대로 종산란구에 제 1차교미잠품종의 수정란이 섞여서 산란됨을 알았다. 따라서 제 1차교미 잠품종의 정자와 제 2차교미 잠품종의 정자는 정소내에서 완전히 혼정된다는 것을 의미한다. 2. 이중교배에 있어서 수정력의 강도는 잠품종과 교배순서가 지배하며 이 이외에 약간의 원인이 작용한다고 본다.

• Clinical and Experimental Reproductive Medicine
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• 제16권2호
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• pp.173-177
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• 1989

Defective or inadequate semen quality, usually presenting as low sperm count or poor sperm motility , is recognizable by semen analysis. However, the ability of spermatozoa to fertilize an ovum is not determined used in various experiments. In this study, hamster oocyte sperm penetration assay was used to determine the fertilizing capacity of sperms in 20 subjects which divided into two groups, group A with 10 normal fertile men, and group B with 10 infertile men. The % penetration in group A and group B were 61% and 35% respectively, which showed statistically not significant but fertilization index was significantly different between group A(FI=2.24) and group B(FI=O.05). Additionally it seemed that the percentage of sperm penetraton was influenced more by the motility of spermatozoa than by the number.

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2004년도 제47차 추계학술대회
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• pp.83.1-83.1
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• 2004

• Journal of Plant Biology
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• 제35권4호
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• pp.339-358
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• 1992

한국산 나자식물 6개과에서 대표적인 1종씩을 선정하여 수피의 특징을 형태 및 해부학적으로 조사하고 기재하였다. 수피를 인위적으로 조직단위로 간주할 경우 수피의 색, 두께, 내수피와 외수피의 두께, 확장조직의 유무 및 발달정도, 조피내 주피의 층우와 주피의 층수와 주피의 구성요소들의 두께, 2기 사부지역 각 구성요소들의 배열양상과 점유면적 비율 등은 종류에 따라 차이를 보였다. 또한 보강세포의 형태와 사세포의 사역 등도 앞으로 상세한 조사가 수행될 경우 비교형태학적 연구에 매우 가치있는 정보를 제공할 것으로 생각되었다.

• 대한의생명과학회지
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• 제11권3호
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• pp.333-336
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• 2005

Environmental endocrine disruptors are very toxic to the animals including humans. They are hormone-like acting chemicals which can be found in our normal daily life. We have examined the toxic effect of bisphenol A and if lactic acid bacteria could suppress this toxic effect. Thirty rats were divided into three groups (control, bisphenol A treated, bisphenol A and lactic acid bacteria treated). Treatments were carried out at an interval of 12 hours for each group. Control group showed normal and clear morphology of tissues. Cells were fine in their shape and color, and density was high enough for the normal function. However, bisphenol A treated group was abnormally destructed in cell morphology. In the testis, sperms were totally destructed. When treated with lactic acid bacteria together, the toxic effect of bisphenol A was clearly decreased. This study indicated that bisphenol A was toxic in any concentration especially for the liver and testis, however, lactic acid bacteria could suppress the toxic effects of bisphenol A.

• Journal of Plant Biology
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• 제36권3호
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• pp.241-249
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• 1993

The pattern of RNA synthesis during male gametogenesis of Brassica napus was studied using 3H-uridine autoradiography. No incorporation of isotope occurred in the newly released microspore and the nonvacuolate, furrowed microspore. Peak incorporation of label during male gametogenesis occurred in the uninucleate, furrowed microspores showing various degrees of vacuolation. In this microspore stage, silver grains were localized in the nucleus and cytoplasm. Moderate incorporation of the isotope occurred in the nulceus of the vacuolated microspore. After the microspore mitosis, isotope incorporation occurred predominantly in the nucleus of the vegetative cell with little or no incorporation in the generative cell. In tricellular pollen, no incorporation of isotope was observed in both the vegetative nucleus and the sperms. Silver grains almost completely disappeared from tricellular mature pollen grains ready to germinate.

• 한국임상수의학회지
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• 제14권2호
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• pp.297-300
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• 1997

Artificial insemination with frozen canine semen using vaginal endoscope was performed in a two years old Golden Retriever to investigate the feasibility of this technique. The bitch was in her second estrus. Blood progesterone concentration was evaluated every two days to decide the timing of insemination since vaginal bleeding was observed. Insemination was performed twice in 48 hours interval on the fourth and sixth posterior to LH surge, respectively. The volume of frozen semen injected was 1.5 ml $(1{\times}10^{8}$ sperms/1ml of semen). The bitch was pregnant and she whelped a female pup on sixty one days after first insemination.

• 한국양식학회지
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• 제12권1호
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• pp.1-5
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• 1999

황복(Takifugu obscurus) 정자의 냉동보존을 위한 기초자료를 얻고자, 냉동보존 조건에 관한 연구를 수행하였다. 황복 정자의 냉동보존을 위한 희석액으로는 다른 여러 가지 희석액에 비해 MFRS가 가장 적합하였으며, 동해방지제로는 DMSO가 glycerol에 비해 효과가 좋은 것으로 나타났다. MFRS를 희석액으로 하고 동해방지제인 DMSO를 최종농도가 5%되도록 첨가하여 정자를 냉동보존하였을 때, 해동정자의 수정률은 74.3±7.5%로 가장 보존효과가 좋았다.

• Journal of Radiation Protection and Research
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• 제32권4호
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• pp.184-189
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• 2007

저선량 방사선에 의한 생물학적 효과를 규명하기 위하여, 쥐의 전신에 저선량 X-Ray을 조사하여 쥐의 정자에 미치는 생물학적효과를 관찰하였다. 실험용 동물인 Sprague-Dawley(SD) rat 총 36마리를 6마리씩 구분하여, 각각 대조군, 10 mGy, 20 mGy, 50 mGy, 100 mGy, 200 mGy의 X-Ray을 전신 조사하였다. 0.1g 당 정자수는 각각 $14.216{\times}10^6,\;13.901{\times}10^6,\;14.153{\times}10^6,\;13.831{\times}10^6,\;14.137{\times}10^6,\;14.677{\times}10^6$로 통계적인 차이는 나타나지 않았고, 정자의 운동성은 각각 50.9%, 49.5%, 55.1%, 54.3%, 48.0%, 52.2%이었다. 그리고 남성호르몬은 대조군에 비하여 모두 증가함을 보였고, 현미경 시야에서 고환조직을 확인한 바로는 정세관, 정소세포에서 공포화가 나타나지 않았다. 이 같은 결과로부터 과학기술부와 보건복지부의 법령에서 제한하는 선량이하에서 피폭선량이 관리된 SD rat에게 유해한 효과가 나타나지 않았다. 그러나 이와 같은 연구의 결과는 제한된 숫자의 동물에게서 확인한 결과이므로 인체에서 동일한 효과가 나타난다고 주장할 수 없다. 그러므로 향후 다른 동물과 궁극적으로 인체에 나타나는 효과에 대한 추가적인 연구가 이루어져야 할 것이다.