• Journal of Periodontal and Implant Science
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• 제45권3호
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• pp.111-119
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• 2015

Purpose: The purpose of this animal study was to perform a histological and histomorphometric analysis in order to elucidate the effect of fibroblast growth factor-2 (FGF-2) on injured periodontal ligament (PDL) and cementum after tooth replantation in dogs. Methods: The roots of 36 mandibular premolars from six mongrel dogs were used in this study. The roots were randomly divided into three groups: (1) a positive control group (n=12), in which the PDL was retained; (2) a negative control group (n=12), in which the PDL and the cementum between the notches were removed; and (3) an experimental group (n=12), in which the PDL and the cementum between the notches were removed and the roots were soaked in an FGF-2 solution ($30{\mu}g/0.1mL$). After treating the root surfaces, the extracted roots were replanted into extraction sockets. The animals were sacrificed four and eight weeks after surgery for histologic and histomorphometric evaluation. Results: At four and eight weeks, normal PDLs covered the roots in the positive control group. In the negative control group, most replanted roots showed signs of replacement resorption. In the experimental group, new PDL-like tissue and cementum-like tissue were observed to partially occupy the region between the root surfaces and the newly formed bone. Histomorphometric analysis showed that the mean length of the newly formed cementum-like tissue on the roots treated with FGF-2 was significantly greater than that of the tissue on the roots in the negative control group (four weeks, P=0.008; eight weeks, P=0.042). However, no significant differences were observed between the roots treated with FGF-2 and the negative control roots with respect to newly formed PDL-like tissue. Conclusions: The results of this study suggest that use of FGF-2 on injured root surfaces promotes cementogenesis after tooth replacement in dogs.

• 한국약용작물학회지
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• 제23권3호
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• pp.198-206
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• 2015

This study was conducted to investigate the effects of sowing density, number of seeds sown per hole, and thinning treatment on growth characteristics and disease occurrence in Panax ginseng under direct sowing cultivation in a blue plastic greenhouse. Seedling were grown from 2 or 3 seeds sown, and the healthiest was only retained, while the rest were thinned out at the foliation stage. $NO_3$-N, $P_2O_5$, and organic matter content differed significantly between growth conditions in the plastic greenhouse and in conventional shade in the soil. Disease also tended to be higher in the conventional shade than in the plastic greenhouse. Plant height and stem length showed an increasing trend with increasing sowing density and number of seeds sown per hole. However, these measures noticeably decreased when thinning treatment was conducted. Growth of the subterranean part of ginseng was not markedly influenced by sowing density, the number of seeds sown per hole, or thinning treatment. Root weight, which is an important factor in yield, was significantly affected by the number of seeds sown and thinning treatment. Interestingly, root weight tended to be higher in the thinning treatment plot than the untreated control plot. Damping-off and root rot increased noticeably as the number of seeds sown increased. Disease also tended to be substantially higher in the thinning treatment plot than the untreated control. However, physiological disorder of the plants did not vary with sowing density, the number of seeds sown, or thinning treatment.

• 농업과학연구
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• 제37권2호
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• pp.199-207
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• 2010

This research was conducted to determine the influence of physiological and chemical properties of root substrates on the growth of the daughter plants of 'Maehyang' strawberry produced by bag culture. The daughter plants produced by stock plants during bag culture were individually separated and grown in 10-cm diameter plastic pots containing six different formulations of root substrates: a) 50% peatmoss plus 50% vermiculite (5:5 by volume, A), b) 70% peatmoss plus 30% perlite (7:3, B), c) 70% coir dust plus 30% perlite (7:3, C), d) mixture of 35% coir dust, 35% peatmoss, and 30% perlite (3.5:3.5:3.0, D), e) mixture of 20% rice hull, 70% coir dust, and 10% perlite (2:7:1, E), and f) 30% rice hull plus 70% coir dust (30:70, F). The container capacity and air filled porosity of the growing medium varied greatly among the six substrate formulations evaluated. The substrates E and F had less container capacity and higher air-holding spaces than the rest of the formulations. Therefore, these two formulations (E and F) may cause a problem in water management during the production of healthy daughter plants. The substrate formulations A, B, and D retained higher nitrogen (N) concentrations than other formulations containing coir dust or rice hull. The substrate formulations E and F which contained rice hull had lower N, phosphorus (P), and potassium(K) concentrations than other substrate formulations containing coir. The quality of the daughter plants grown in all six different substrate formulations was good with the crown diameters at around 10 mm. Fresh weights of the daughter plants grown in substrate formulations A, C, and D were higher than those obtained from B, E, and F. Dry weights of the daughter plants showed a similar trend. The daughter plants having high fresh and dry weights and increased crown diameter are in demand by the industry. For this reason, the substrate formulations A, C and D can readily be used as potting mixes during the production of 'Maehyang' strawberry transplants utilizing the bag culture system.

• 농업과학연구
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• 제43권4호
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• pp.522-536
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• 2016

Fluorine is unique chemical element which occurs naturally, but is not an essential nutrient for plants. Fluoride toxicity can arise due to excessive fluoride intake from a variety of natural or manmade sources. Fluoride is phytotoxic to most plants. Plants which are sensitive for fluorine exposure even low concentrations of fluorine can cause leave damage and a decline in growth. All vegetation contains some fluoride absorbed from soil and water. The highest levels of F in field-grown vegetables are found up to $40mg\;kg^{-1}$ fresh weight although fluoride is relatively immobile and is not easily leached in soil because most of the fluoride was not readily soluble or exchangeable. Also, high concentrations of fluoride primarily associated with the soil colloid or clay fraction can increase fluoride levels in soil solution, increasing uptake via the plant root. In soils more than 90 percent of the natural fluoride ranging from 20 to $1,000{\mu}g\;g^{-1}$ is insoluble, or tightly bound to soil particles. The excess accumulation of fluorides in vegetation leads to visible leaf injury, damage to fruits, changes in the yield. The amount of fluoride taken up by plants depending on the type of plant, the nature of the soil, and the amount and form of fluoride in the soil should be controlled. Conclusively, fluoride is possible and long-term pollution effects on plant growth through accumulation of the fluoride retained in the soil.

• 대한소아치과학회지
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• 제26권1호
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• pp.38-43
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• 1999

치아전위는 비교적 드문 발육장애이다. 적절하게 차단치료된다면 예방이 가능할 뿐 아니라 이후의 교정과 수복과정이 보다 용이할 수 있다. 이를 위한 8-9세 경의 조기 임상검사가 이러한 발육장애의 인지를 위해 추천된다. 일단 전위가 일어난 경우에는, 부정교합을 교정하고 최상의 기능적, 심미적 결과를 얻기 위해 주의깊은 교정적 평가가 요구된다. 이상적인 결과를 얻기 위하여 두 치아를 원래의 위치로 환원시키는 치료가 요구되나, 완전전위되어 두 치아가 맹출되었다면 전위된 상태로 치아를 배열하여도 비교적 양호한 결과를 얻을 수 있었다.

• Advances in environmental research
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• 제3권1호
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• pp.71-86
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• 2014

Macronutrients ($Na^+$, $K^+$, $Ca^{2+}$, $Mg^{2+}$), yield and yield components, bioaccumulation and translocation of metal in plant parts of three Vigna species (V. cylindrica, V. mungo, V. radiata) were evaluated at 0, 50, 100 and $150mgkg^{-1}$ soil of Nickel (Ni). A marked inhibition (p < 0.001) in the distribution of various macronutrients was noticed in these Vigna species except for $Mg^{2+}$ content of the shoot and leaves. Similarly, all species retained more $Ca^{2+}$ in their roots (p < 0.05) as compared to the aerial tissues. Ni induced a drastic decline (p < 0.001) for various yield and yield attributes except for 100 seed weight. Toxicity and accumulation of Ni in plant tissues considerably increased in a concentration dependent manner. Vigna species signify an exclusion approach for Ni tolerance as both bioaccumulation factor (BF) and translocation factor (TF) were less than 1.0. The Ni content of plants being root > shoot > leaves > seeds. Scoring for percentage stimulation and inhibition (respective to control) at varying levels of Ni revealed tolerance of the species in an order of V. radiata > V. cylindrica > V. mungo. The acquisition of Ni tolerance in V. radiata seems to occur through an integrated mechanism of metal tolerance that includes sustainable macronutrients uptake, stronger roots due to greater deposition of $Ca^{2+}$in the roots, restricted transfer of Ni to above ground tissues and seeds as well as exclusion capacity of the roots to bind appreciable amount of metal to them. Thus, metal tolerant potential of V. radiata could be of great significance to remediate metal contaminated soil owing lesser impact of Ni on macro-nutrients, hence the yield.

• 대한장애인치과학회지
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• 제11권1호
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• pp.1-4
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• 2015

본 증례는 뇌성마비가 있는 혼합치열기의 청소년에서 치간이개를 개선하는 다양한 방법을 모색해보았다. 그 중 복합레진을 이용한 보존적 치료는 이동에 어려움이 있는 뇌성마비 환아에서 최소한의 내원 횟수, 짧은 술식 시간, 경제적이며, 가역적이고 단순한 치료법이다. 이를 통해 높은 심미적 만족도와 발음 및 교합력 개선을 통해 본 환아의 삶을 질을 높일 수 있을 것으로 기대한다.

• 대한소아치과학회지
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• 제31권1호
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• pp.52-58
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• 2004

과잉치는 유치열에서 0.3-0.8%, 영구치열에서 1.0-3.5% 정도로 발생하며, 2:1로 남자에게 호발 9:1로 상악에서 호발한다. 그 중 하악 전치부에서 발생하는 빈도는 전체 과잉치중에서 2-4%의 매우 낮은 빈도를 보인다고 보고되었다. 과잉치가 계속 존재할 경우 나타날 수 있는 합병증으로서 치간이개, 인접한 정상치아의 맹출장애, 치관의 형성이상, 인접치의 치근흡수, 함치성 낭종 등을 들 수 있으며, 치열 발육 중인 어린이의 경우 성장 중임을 감안하여 바람직한 교합유도를 위한 정확한 진단과 함께 적절한 처치가 필요하다. 본 증례는 전북대학교병원 소아치과에 내원한 6세 환아의 하악 전치부에서 발견된 양측성 매복 과잉치로서 그 중 한개는 영구치와 융합된 경우를 보고하는 바이다.

• 원예과학기술지
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• 제29권1호
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• pp.16-22
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• 2011

Polyoxyethylene nonylphenyl ether와 polyoxyethylene castor oil을 1:1(v/v)로 혼합하여 조제한 액상 토양습윤제(LWA)가 피트모스 + 펄라이트(7:3) 상토내 잔류성, 혼합상토의 초기 습윤화 및 고추(Capsicum annuum L. 'Knockwang') 플러그묘의 생육에 미치는 영향을 구명하고자 본 연구를 수행하였다. 토양습윤제의 처리량이 증가할수록 상토의 보수량이 뚜렷하게 증가하였고 본 연구에서 제조한 토양습윤제를 $2.5mL{\cdot}L^{-1}$의 비율로 처리한 구의 보수량이 AquaGroL을 $3.0mL{\cdot}L^{-1}$을 처리한 +대조구와 유사하였다. 처리된 토양습윤제는 처리 후 1 및 2번째 관수에서 대부분 용탈되었고, 10회 관수할 때까지 서서히 낮아지다가 10회 관수 이후에는 매우 낮은 농도로 분석되었다. 개발된 토양습윤제를 처리한 상토에서 관수한 수분의 수직방향으로 하강 속도를 측정한 결과 0.5, 1.0, 및 $1.5mL{\cdot}L^{-1}$의 비율로 처리한 구에서 -대조구보다 월등히 빨랐으나, 토양습윤제의 처리비율이 $2.0mL{\cdot}L^{-1}$ 이상으로 높아지면 점차 느려지는 경향을 보였다. 습윤제를 처리한 상토를 충분히 관수하고 온실에서 상토의 건조속도를 조사한 결과 무처리구의 건조속도가 가장 빨랐고, 개발된 토양습윤제의 처리비율이 높아질수록 상토의 건조속도가 느렸다. 파종 8주 후에 조사한 고추 플러그 묘의 생육에서 초장은 $0.5mL{\cdot}L^{-1}$ 처리에서 22.2cm로 가장 컸고, 줄기직경은 $1.0mL{\cdot}L^{-1}$ 처리에서 3.46mm로 가장 굵었으며, 생체중과 건물중은 $1.0mL{\cdot}L^{-1}$ 처리구에서 각각 식물체당 3.08g과 0.861g으로 조사되어 다른 시험구에 비해 유의하게 우수하였다. 그러나 $1.5mL{\cdot}L^{-1}$ 이상으로 토양습윤제의 처리량이 높아지면 점차 생육이 저조하였으며, 적정 처리량은 $1.0mL{\cdot}L^{-1}$라고 판단하였다.

• 한국환경농학회지
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• 제5권2호
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• pp.95-100
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• 1986

비소(砒素)의 토양처리(土壤處理)에 의한 수도체(水稻體)의 비소흡수(砒素吸收) 정도(程度) 및 생육(生育)에 미치는 영향(影響)을 조사(調査)하기 위하여 양토(壤土)와 사양토(砂壤土)에 수용성(水溶性) 염(鹽)인 $Na_2HAsO_4{\cdot}7H_2O$로 비소(砒素)의 농도(濃度)가 0, 10, 25, 50, 100 및 150 ppm되게 각각(各各) 처리(處理)하여 pot 시험(試驗)한 결과(結果)는 다음과 같다. 1) 수도수량(水稻收量)은 토양중(土壤中) 비소농도(砒素濃度)가 높아짐에 따라 유의성(有意性) 있게 감소(減少)되었고 토성별(土性別) 유의성(有意性)있는 감소농도(減收濃度)는 사양토(砂壤土)가 2.75ppm, 양토(壤土)가 6.79ppm이었다. 2) 수량구성요소(收量構成要素)도 토양중(土壤中) 비소농도(砒素濃度)가 높아질수록 유의성(有意性)있게 각각(各各) 감소(減少)되었고 이중 천입중(千粒重)이 가장 높은 상관(相關)($-0.893^{{\ast}{\ast}}$)을 나타내었다. 3) 수도체(水稻體) 비소(砒素)는 대부분(大部分) 뿌리에 축적(蓄積)되어 있고 소량(小量)이 지상부(地上部)로 이행(移行)되었으며 부위별(部位別) 함량(含量)은 뿌리>줄기>엽신(葉身)>엽초>현미(玄米)의 순(順)으로 높았다. 4) 부임입수(不姙粒數)는 토양중(土壤中) 비소농도(砒素濃度)가 높을수록 증가(增加)되었으며 토성별(土性別)로는 사양토구(砂壤土區)가 양토구(壤土區) 보다 더 많았다.