• The Korean Journal of Ecology
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• 제7권4호
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• pp.185-193
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• 1984

Regneration process of Abies koreana-Pinus koraiensis community consisted of a subalpione coniferous forest in Mt. Jiri, Korea, was studied in relation to age structure, especially to gap formation. The tall-tree layer (ca. 6.5m) is dominated by Abies koreana and Pinus koraiensis, while lower layer by the sapling and juveniles of A. koreana and Picea jezoensis below 2m tall. The ranges of DBH in A. koreana, P. koraiensis and P. jezonesis were 11.8cm~26.4m, 11.7cm~24.5 cm and 18.2cm~21.7 cm, respectively. The trees below 130 cm tall had contagious distribution, while tall and subtall trees had uniform distribution. The average tree ages of A. koreana, P. koraieniensis and P. jezoensis were 60~70 years, 70~80 years and 70~90 years, respectively. The saplings and juveniles below 20 years in tree ages were occupied over 80% of total trees. The coniferous trees in the gaps or around dead trees were composed of sapligs and juveniles which had emerged or invaded about 20 years before and after the gap formation. The Betula type regeneration of the coniferous forest took place in gaps which orginated from the failing down of a single or a few trees by longevity. Accordingly, it is clear that the subalpine coniferous forest composed of A. koreana of A. koreana, P. koraiensis and P. jezoensis in Mt. jiri was supporting by the regeneration pattern of Betula type.

• Journal of Yeungnam Medical Science
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• 제9권2호
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• pp.422-426
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• 1992

저자들은 회귀하고도 사망율이 높은 선천성 피부결손증 1례를 경험하고 국소피판과 피부이식으로써 치료하고 비교적 만족한 결과를 얻었기에 문헌고찰과 함께 보고하는 바이다.

• 대한화학회지
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• 제46권2호
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• pp.117-124
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• 2002

활성탄에 흡착되어 있는 유기질을 처리하기 위하여 역류산화반응이 개발되었고 그것에 대한 평가가 이루어 졌다. 역류산화반응이란 산소의 흐름과 반대로 이동하는 자발적인 불꽃을 이용하여 유기질을 파괴 및 제거함과 동시에 폐활성탄을 재생하는 방법이다. 본 연구를 통하여 얻어진 실험결과를 고찰해 보면, 활성탄의 질량손실과 불꽃의 온도가 산소의 흐름속도에 절대적으로 의존하였고, 재생탄의 비표면적이 거의 완전히 회복되었으며, 특히 활성탄에 흡착되어 있는 열에 안정한 PCBs를 거의 완전히 파괴 및 제거(99.99%이상)할 수 있었다.

• 한국약용작물학회지
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• 제13권6호
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• pp.273-277
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• 2005

지황 (R. glutinosa)의 조직절편으로부터 고효율의 식물체 재분화 시스템을 확립하기 위하여 기내에서 발아된 유묘의 잎을 절취하여 auxins과 cytokinins을 농도별로 단독 또는 혼합하여 MS배지에 치상한 후 신초의 형성율을 조사하였다. 잎 절편으로부터 부정아의 형성율은 1 mg/{\ell}\;BA와\;2mg/{\ell}$ IAA가 첨가된 MS배지에서 93.4%로 가장 높았다. 한편, 엽령에 따른 부정아의 형성율을 조사한 결과 기내에서 발아 후 6주가 지난 유식물체의 정단부위로부터 3번째의 잎을 사용함으로써 신초의 형성율을 98.4%까지 높일 수 있었다. 형성된 신초는 $0.1mg/{\ell}$ IBA가 첨가된 1/2MS배지로 옮겼을 때 4주 후 최대 발근율을 보여주었다.

• Journal of Periodontal and Implant Science
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• 제31권1호
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• pp.91-109
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• 2001

The purpose of this study is to evaluate histologically the resorption and tissue response of various resorbale membranes used for guided tissue regneration procedures, using a subcutaneous model on the dorsal surface of the rat. In this study, 12 Sprague-Dawley male rats(mean BW 150gm) were used and the commercially available materials included dense collagen membrane, freeze-dried bovine dura mater loos collagen membrane, PLA/PLGA membrane. Animals were sacrificed at 3, 6 and 8 weeks after implantation of various resorbable membranes. Specimens were prepared with Hematoxylin-Eosin stain for light microscopic evaluation. The results of this study were as follows: 1. Resorption : Loose collagen membrane group was resorbed most rapidly. Dense collagen membrane group and freeze-dried bovine dura mater group were rarely resorbed. 2. Inflammatory reactions : PLA/PLGA membrane group showed persistent and severe inflammatory reactions for 3 to 8 weeks. Moderate inflammatory reactions and the ectopic formation of calcified material were observed in dense collagen membrane group. Freeze-dried bovine dura mater group and loose collagen membrane group showed mild inflammatory reactions 3. In PLA/PLGA membrane group, multinucleated giant cells by foreign body reactions were observed. In conclusion, the resorption of freeze-dried bovine dura mater didn't happen for 3-6weeks, which showed the best bio-compatibility. Therefore, freeze-dried bovine dura mater was considered proper resorbable membrane for guided tissue regeneration.