http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Effective Methods to Improve the Biocompatibility of Poly(dimethylsiloxane)
박중열,황창모,이상훈 한국바이오칩학회 2008 BioChip Journal Vol.2 No.1
Poly (dimethylsiloxane) (PDMS) has become one of the popular materials in the field of bio-related microfluidic systems, and has been used for various biological assays. While the material is known to be biocompatible in general, it also has been reported that the attachment and survival rate of cells are limited on a PDMS substrate. In this paper, a simple and relevant method to improve heiocompatibilityof PDMS is proposed; the effects of various treatments using ethanol, water, and boiling-water were evaluated. The results show that the boiling-water treatment is the most appropriate, time saving, and simple method to improve the biocompatibility of PDMS.
박중열,유성주,이은중,이대호,김지영,이상훈 한국바이오칩학회 2010 BioChip Journal Vol.4 No.3
We monitored the viability and morphology of mouse fibroblast cells cultured on PDMS sub strates with different degrees of polymer stiffness. The stiffness was controlled by varying the ratio between base and crosslinker agent during mixing. Although the standard PDMS mixing ratio is 10 : 1 (base to crosslinker; Young’s modulus, E=580 kPa), we found that a PDMS substrate with a high stiffness (mixing ratio of 5 : 1, E=1,000 kPa) was more favora ble as a substrate for fibroblast cell growth. It is important to note that an extracellular matrix coating was not applied to the PDMS so that the effect of stiffness on cell growth could be studied in isolation. A stiffness reduction of 40% (from a mixing ratio of 5 : 1 to 10 : 1)produced a significant reduction in survival rate (viability was reduced by 15%), and viability worsened (was reduced by 45%) for a substrate stiffness of 280 kPa (a mixing ratio of 20 : 1). The rate of spreading for the cells was measured to show that stiffer materials promoted more prolific fibroblast growth. These results provide PDMS stiffness guidelines for cell culture substrates.
탄소섬유판으로 휨보강된 철근콘크리트 보의 거동예측을 위한 해석적 연구
박중열,조홍동,한상훈 충북대학교 건설기술연구소 2003 建設技術論文集 Vol.22 No.2
Composite materials which have superior mechanical, chemical properties in comparison with conventional materials are used to strengthen RC structures and related studies are actively performed. Especially, the studies on behavior prediction of RC beam strengthened with CFRP plate are peformed recently. RC beams strengthened with CFRP plate appear material non-linearity, occurrence of cracks, geometric non-linearity, so behavior prediction based on linear-elastic theory may differ from experimental results. Therefore, in this study, to predict the behavior of RC beam flexurl strengthened with CFRP plate, analytical program considering material non-linearity is developed. To analyze, strain compatibility and force equilibrium are applied and internal forces of constitutive material are calculated using non-linear stress-strain relationship. To certainty the reliability of analytical program, deflection, strain of CFRP plate, change of neutral axis on cross section and crack distribution at failure are compared with those of experiment, and each results is almost coincident.
박중열,이병두,김웅,이홍규,고창순,민헌기,오승근,이진용,홍기석 대한내분비학회 1987 Endocrinology and metabolism Vol.2 No.2
About 10% of pheochromocytoma occurs in familial pattern and familial pheochromocytoma has a autosomal dominant mode of inheritance with varing degree of penetrance. It has been well known that the diagnosis before delivery and adequate management of pheochromocytoma during pregnancy markedaly reduce both maternal and fetal mortality. We report two cases of pheochromocytoma in two systers. One of which was bilateral, multiple adrenal tumors and the other was developed during pregnancy. The latter was diagnosed at antepantum and treated with alpha-and selective beta_1-adrenergic receptor blockades till delivery and then with successful simultaneous cesarean section and excision of tumors under thipental, nitrous oxide-oxygen-ethrane general anesthesia at 37 weeks of gestation. In conclusion, it is suggested that the family history and the life long follow-up of the patient with pheochromocytoma are very imporant to detect the familial pheochromocytoma and the multiple endocrine neoplasia. Hypertensive patient during pregnancy must be differentiated from a pheochromocytoma and the correct antepartum diagnosis and proper management may menkedly reduce maternal and fetal mortality.