• 한국안전학회지
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• 제12권3호
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• pp.38-44
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• 1997

6063-T5 alloys are tested in laboratory air, water and 3% NaCl solution to investigate the effects of corrosive environment on the retardation behavior through single overload fatigue test. Also, the fatigue crack propagation and the crack closure behavior are studied. The results obtained in this experimental study are summarized as follows. 1) Behaviors of fatigue crack growth retardation are observed in water and 3% NaCl solution as they do in air. The number of delay cycles and the size of affected region by single overload decrease greatly in water and 3% NaCl compared with those in air. 2) In fractographic results, the overload marking by single overload appear remarkably in air, but indistinctly in water and 3% NaCl solution. 3) The effect of crack closure on crack propagation is most remarkable in the beginning of crack propagation. With crack propagation, the crack closure level and its effect decrease greatly.

• 항공우주시스템공학회지
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• 제1권1호
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• pp.45-52
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• 2007

This paper analyzed the extension effects of fatigue life and the application of pre-indentation in aircraft structural material such as aluminum alloys. The test specimen used the thin sheet of aluminum alloy with a single-edged notch. The experiments were conducted after making the pre-crack under a constant amplitude loading. As the fatigue life extension technique, the pre-indentation making an indent on the predicted path of crack propagation was applied. The work presented here discussed about a proper mathematical relation between crack growth rate and the range of stress intensity factor and about the generalization of crack growth mechanism with large retardation effect. A technique to enhance the applicability of pre-indentation if also mentioned.

• 한국환경과학회지
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• 제11권12호
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• pp.1315-1320
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• 2002

Since the enzymatic degradation of microbial poly[(R)-3-hydroxybutyrate-co-3-hydroxyvalerate] (P(3HB-co-3HV)) initially occurs by a surface erosion process, a degradation behavior could be controlled by the change of surface property. In order to control the rate of enzymatic degradation, plasma gas discharge and blending techniques were used to modify the surface of microbial P(3HB-co-3HV). The surface hydrophobic property of P(3HB-co-3HV) film was introduced by CF$_3$H plasma exposure. Also, the addition of small amount of polystyrene as a non-degradable polymer with lower surface energy to P(3HB-co-3HV) has been studied. The enzymatic degradation was carried out at 37 $^{\circ}C$ in 0.1 M potassium phosphate buffer (pH 7.4) in the presence of an extracellular PHB depolymerase purified from Alcaligenes facalis T1. Both results showed the significant retardation of enzymatic erosion due to the hydrophobicity and the enzyme inactivity of the fluorinated- and PS-enriched surface layers.

• BMB Reports
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• 제41권5호
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• pp.363-368
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• 2008

Two genes of temperate mycobacteriophage L5, namely, gp63 and gp64, were hypothesized to be toxic to M. smegmatis. An identical L5 gp64 ortholog (designated hlg1) was cloned from homoimmune mycobacteriophage L1 and characterized at length here. As expected, hlg1 affected the growth of M. smegmatis when overexpressed from a resident plasmid. HLG1 (the protein encoded by hlg1) in fact caused growth retardation of M. smegmatis and the region encompassing its 57-114 C-terminal amino acid residues was found indispensable for its growthretardation activity. Both nucleic acid and protein biosynthesis were severely impaired in M. smegmatis expressing HLG1. Interestingly, HLG1 also affected E. coli almost similarly. This putative delayed early lipoprotein did not participate in the lytic growth of L1.

• Neonatal Medicine
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• 제28권1호
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• pp.48-52
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• 2021

Aplasia cutis congenita (ACC) is a rare congenital disorder characterized by skin defects involving the epidermis, dermis, subcutaneous tissue, bone, and sometimes dura. It commonly affects the scalp in approximately 70% of cases, but the neck, trunk, and the extremities can also be affected. ACC can occur either as an isolated condition or associated with other anomalies and congenital syndromes, and it can be acquired either genetically or sporadically. Morbidity and mortality are associated with the defects of skull bone, dura, and other multiple anomalies. We herein report the case of a female infant, with a large scalp defect accompanied by a skull defect noted at birth, who developed mental retardation in the preschool years.

• 사상체질의학회지
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• 제20권3호
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• pp.151-163
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• 2008

1. Objective This study was done to identify the anti-stress effect of Hyeongbangdojeok-san (HDS), Yanggyeoksanhwa-tang(YST) in Soyangin. 2. Methods Experimental animals were composed of YST, HDS+stress groups which were administered each by 200mg/kg, 400mg/kg and the Saline+stress group. On the 1st day, making the rats forced swim and on the 2nd day, applying Forced swimming test to the rats. After FST, the levels of Corticosterone in the blood were measured. For the study of learning retardation, memory ability and anxiety reaction, experimental animals were composed of YST, HDS+restraint stress groups which were administered each by 400mg/kg, no stress group and the Saline+restraint stress group. Restraint stress were applied 2 hours a day for 3 weeks. On the last day of the 3rd week, Elevated Plus Maze(EPM) was applied to the groups and Morris Water Maze(MWM) was applied to the groups for 7 days. 3. Results 1. As the results of measuring FST which reflects depression, the YST+stress group and the HDS+stress group showed significant effect in comparison with the Saline+stress group. The levels of Corticosterone in the blood were decreased only in the 400mg/kg YST+stress group. 2. As the results of measuring how long EPM which reflects anxiety reaction stayed in the open arm, there was the trend which can suppress anxiety reaction in the HDS+restraint stress group bur no statistical significance. But there was any suppression of anxiety reaction in the YST+restraint stress group. 3. According to the result of MWM, the saline+restraint stress group showed the learning retardation which means increased time arriving at goal compared to the normal group at the second and third day of measurement. On the contrary, a learning retardation was significantly decreased in the YST+restraint stress group at the third day of measurement. 4. Among the Probe trial test a memory loss occurred in the saline+restraint stress group, but memory ability was significantly increased in the YST+restraint stress group. 4. Conclusion: As the results above, Soyangin Yanggyeoksanhwa-tang has significant influence to the antidepression effect, the learning retardation, the anxiety reaction and also in the Hormone level. Hyeongbangdojeok-san has significant influence to the antidepression effect, in the Hormone level, bur not to the learning retardation and anxiety reaction. prefer to drink cold water, and who are suffering from chronic gastritis.

• Asian-Australasian Journal of Animal Sciences
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• 제22권11호
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• pp.1495-1503
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• 2009

This experiment was conducted to determine the effect of dietary supplementation with BCAA (branched-chain amino acids: leucine, isoleucine and valine) on improving the growth of rats in a malnutritional IUGR (Intrauterine Growth Retardation) model, which was established by feeding restriction. In the experimental treatment, rats were fed purified diets supplemented with BCAA (mixed) during the whole gestation period, while arginine and alanine supplementation were set as the positive and negative control group, respectively. The results showed that, compared to the effect of alanine, BCAA reversed IUGR by increasing the fetus weights by 18.4% and placental weights by 18.0% while fetal numbers were statistically increased. Analysis of gene and protein expression revealed that BCAA treatment increased embryonic liver IGF-I expression; the uterus expressed higher levels of estrogen receptor-$\alpha$ (ER-$\alpha$) and progesterone receptor (PR), and the placenta expressed higher levels of IGF-II. Amino acid analysis of dam plasma revealed that BCAA supplementation effectively enhanced the plasma BCAA levels caused by the feed restriction. BCAA also enhanced the embryonic liver gluconeogenesis by augmenting the expression of two key enzymes, namely fructose-1,6-biphosphatase (FBP) and phosphoenolpyruvate carboxykinase (PEPCK). In conclusion, supplementation of BCAA increased litter size, embryonic weight and litter embryonic weight by improving the dam uterus and placental functions as well as increasing gluconeogenesis in the embryonic liver, which further provided energy to enhance the embryonic growth.

• Clinical and Experimental Pediatrics
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• 제46권6호
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• pp.597-601
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• 2003

저자들은 저출생 체중과 호흡 곤란을 주소로 출생 직후 이송 된 여아에서, 진찰상 안면과 골격계 기형 소견 보여 말초 혈액에서 시행한 염색체 핵형 검사에서 trisomy 9, low level mosaic type으로 진단되었던 1례를 경험하였기에 보고하는 바이다.

• 구강회복응용과학지
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• 제30권3호
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• pp.246-252
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• 2014

통상적인 임플란트 치료는 식립 후 약 3 - 5개월 뒤 임플란트 상부 보철물을 제작한다. 이러한 치료과정의 단점으로는 환자가 임플란트 식립 후 보철물이 장착되는 최종 치료 시점까지의 기간 동안 유지력과 저작능력이 떨어지는 임시의 치를 사용하여 생활해야 한다는 것이다. 최근의 임플란트 식립 후 즉시 부하 보철물 치료는 시술 적응증에 따른 제한이 있긴 하지만, 잦은 치과 방문이 어렵고 진료에 대한 협조도가 낮은 정신적, 신체적 장애 환자들에게 더욱 유용하다고 생각된다. 본 증례에서는 삼차원 컴퓨터 유도 수술법을 이용한 임플란트 식립 후 즉시 부하 보철치료를 정신지체장애 환자에서 시행하였으며, 시술 후 좋은 경과를 보였기에 이를 보고하는 바이다.

• 대한유전성대사질환학회지
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• 제4권1호
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• pp.23-29
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• 2004

시스틴증은 상염색체 열성으로 발생하는 매우 드문 용해소체 축적병으로서, 용해소체 막을 통한 시스틴 운반의 장애로 발생한다. 용해소체 내 시스틴의 축척과 결정화에 의해 전신의 여러 조직에 파괴가 진행되어 성장 장애, Fanconi 증후군, 신부전, 눈의 이상, 내분비 질환 등이 나타난다. 치료제인 cysteamine의 투여가 예후를 향상시킬 수 있으므로 조기 진단과 치료가 중요하다. 저자들은 성장 장애를 주소로 내원한 12세 남아에서 slit-lamp 검사와 혈액 백혈구 시스틴 농도 측정을 통하여 시스틴증을 확진하고 cysteamine 치료를 시행하면서 추적 관찰 중이다.