• Journal of Biomedical Engineering Research
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• v.16 no.4
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• pp.463-470
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• 1995

Complete prelining of artificial vascular grafts with autologous endothelial cells may be one of the ideal solutions to obtain a nonthrombogenlc blood-contacting surface. To establish an intact endothelial cell monolayer on a prosthetic surface at the time of implantation,a sufficient number of endothelial cells and adequate propagation condition In cell culture are prerequisites. In this experimental study, endothelial cells from microvessels of adult human oriental adipose tissue were enzymatically harvested, and optimal culture conditions for proliferation of the endothelial cells in cell culture were examined. Human oriental adipose tissue was digested with collagenase and endothelial cells were separated from other stromal elements by mesh filtration method. Cultured cells were identified as endothelial cells by immunofluorescent staining for factor VIII-related antigen. Proliferation in usual 20% fetal bovine serum (FBS) medium or medium containing endothelial cell growth factor (ECGF)(5 ng/ml) and heparin (HEP)(1,000 units/ml) were compared,and the effects of adding compounds that increase intracellular cyclic adenosine monophosphate levels, that is,cholera toxin (CT)(1 $\mu\textrm{g}$/ml) and isobutylmethylxanthine (IBMX)(0.2 ml),were also analyzed. In total,following eight media groups were examined. 1) FBS medium + ECGF + HEP, 2) FBS medium + ECGF + HEP+CT, 3) FBS medium+ECGF+HEP+lBMX, 4) FBS medium+ECGF+HEP+CT+ IBMX, 5) FBSmedium, 6) FBS medium +CT, 7) FBS medium + IBMX, 8) FBS medium + CT + IBMX. It was shown that the medium containing ECGF + HEP with or without cholera toxin was most efficient in Stimulating cell proliferation. IBMX was considered to have antagonistic effect to ECGF. Among experimental groups without ECGF and HEP, the addition of cholera toxin and IBMX was shown to significantly potentiate cell proliferation. This results could provide a practical method for use of cultured human endothelial cells for endothelial cell seeding of cardiovascular prosthetic device, particularly in small-diameter vascular grafts.

• Restorative Dentistry and Endodontics
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• v.24 no.2
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• pp.299-309
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• 1999

The composite resin, due to its esthetic qualities, is considered the material of choice for restoration of anterior teeth. With respect to shade control, the direct-placement resin composites offer some distinct advantages over indirect restorative procedures. Visible-light-cured (VLC) composites allow dentists to match existing tooth shades or to create new shades and to evaluate them immediately at the time of restoration placement. Optimal intraoral color control can be achieved if optical changes occurring during application are minimized. An ideal VLC composite, then, would be one which is optically stable throughout the polymerization process. The shade guides of the resin composites are generally made of plastic, rather than the actual composite material, and do not accurately depict the true shade, translucency, or opacity of the resin composite after polymerization. So the numerous problems associated with these shade guides lead to varied and sometimes unpredictable results. The aim of this study was to assess the color changes of current resin composite restorative materials which occur as a result of the polymerization process and to compare the color differences between the shade guides provided with the products and the actual resin composites before- and after-polymerization. The results obtained from this investigation should provide the clinician with information which may aid in improved color match of esthetic restoration. Five light activated, resin-based materials (${\AE}$litefil, Amelogen Universal, Spectrum TPH VeridonFil-Photo, and Z100) and shade guides were used in this study. Three specimens of each material and shade combination were made. Each material was condensed inside a 1.5mm thick metal mold with 10mm diameter and pressed between glass plates. Each material was measured immediately before polymerization, and polymerized with Curing Light XL 3000 (3M Dental products, USA) visible light-activation unit for 60 seconds at each side. The specimens were then polished sequentially on wet sandpaper. Shade guides were ground with polishing stones and rubber points (Shofu) to a thickness of approximately 1.5mm. Color characteristics were performed with a spectrophotometer (CM-3500d, Minolta Co., LTD). A computer-controlled spectrophotometer was used to determine CIELAB coordinates ($L^*$, $a^*$ and $b^*$) of each specimen and shade guide. The CIELAB measurements made it possible to evaluate the amount of the color difference values (${\Delta}E{^*}ab$) of resin composites before the polymerization process and shade guides using the post-polishing color of the composite as a control, CIE standard D65 was used as the light source. The results were as follows. 1. Each of the resin composites evaluated showed significant color changes during light-curing process. All the resin composites evaluated except all the tested shades of 2100 showed unacceptable level of color changes (${\Delta}E{^*}ab$ greater than 3.3) between pre-polymerization and post-polishing state. 2. Color differences between most of the resin composites tested and their corresponding shade guides were acceptable but those between C2 shade of ${\AE}$litefil and IE shade of Amelogen Universal and their respective shade guides exceeded what is acceptable. 3. Comparison of the mean ${\Delta}E{^*}ab$ values of materials revealed that Z100 showed the least overall color change between pre-polymerization and post-polishing state followed by ${\AE}$litefil, VeridonFil-Photo, Spectrum TPH, and Amelogen Universal in the order of increasing change and Amelogen Universal. Spectrum TPH, 2100, VeridonFil-Photo and ${\AE}$litefil for the color differences between actual resin and shade guide. 4. In the clinical environment, the shade guide is the better choice than the shade of the actual resin before polymerization when matching colors. But, it is recommended that custom shade guides be made from resin material itself for better color matching.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.2
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• pp.158-164
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• 1985

The objective of the study was to investigate growth pattern of capsule and grain to improve grain filling during the grain filling period in sesame. Growth patterns of capsule and grain from anthesis to maturity were measured and compared by different plant types. Growth of capsule length started to grow just after anthesis and recorded maximum point at 35 days after flowering. and then decreased gradually. Growth of higher part capsule was worse than lower and middle capsules. Capsule growth of 2 carpels 4 loculi type showed better than 4 carpels 8 loculi type and BTB (branch, 3 capsules, 2 carpels, 4 loculi) type showed good growth due to its small reduction of higher part capsule length compared to those of lower and middle parts. The order of growth of capsule length were considered to be center capsule in main stem> center capsule in branch> side capsule in main stem> side capsule in branch. Growth of capsule width also showed maximum at 35 days after anthesis and then reduced. The order of growth of capsule width were lower part> middle part> higher part. Higher part capsule width of 3 capsules 4 carpels 8 loculi type showed serious decrease at late reproductive growth stage same as those of capsule length. Fresh one thousand grain weight showed peak at 35 days after anthesis and then reduced. The order of grain growth were appeared as lower part> middle part> higher part. Growth of fresh one thousand grain weight of branch and side capsule were lower than those of main stem center capsule, and 4 carpels 8 loculi type was deeply decreased at late flowering time in higher part such as the growth of capsule length and width. BTB (branch, 3,2/4) type didn't show much decrease in higher part fresh grain weight compared to those of other plant types in spite of its profitable character of lots of sink capacity. BTB type appeared to be ideal for improving grain filling and yield productivity in growing sesame in Korea.

• Korean Journal of Environmental Biology
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• v.32 no.2
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• pp.138-152
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• 2014

The objective of the study survey was to determine the effect of marine sand extraction on community composition and rate of recolonization of the meiobenthos following cessation of mining activities. Because of meiobenthic distribution in nature, high abundance, intimate association with sediments, fast reproduction, benthic larva period, sensitivity to pollution and rapid life histories, meiobenthos are widely regarded as ideal organisms to study the potential ecological indicator of natural and anthropogenic stresses. The community structure of meiobenthos was studied at seven stations within sandy tidal and sub tidal zones in Jangbongdo in the Yellow Sea, Korea from Aug. 2006 to Dec. 2007. Meiobenthic samples were collected by three core samples, with a 3.6 cm in diameter, from each sediment sample taken with a Smith-McIntyre Grab. It was found that sand mining often causes complete removal of the sediment and the damage to the habitats of meiobenthos. This study in the effect showed that sand mining resulted in a reduction in total abundance and biomass of meiobenthos in mining area. The finding of this study further showed that initial restoration of abundance and biomass within one year of the cessation of sand mining.

• Research in Community and Public Health Nursing
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• v.11 no.1
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• pp.21-36
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• 2000

The purpose of this study was to assess the needs of breast self examination education (BSEE) programs for developing nursing centers. A first, we reviewed the literature of activity and management-related factors of nursing centers: and, second. we used a questionnaire to discover the degree of knowledge, attitude, and practice on breast cancer, as well as an individual's intention to participate BSEE program. 1. Reviewing the literatures of nursing center activities. Nursing centers which were administered by a professional nurse are an ideal site for faculty and student practices. With the use of nursing models of health. professional nurses in nursing centers diagnose and treat human responses to potential and actual health problems and offer holistic, client-centered health service. In nursing centers professional nursing services include health education, health promotion, and health-related research. A nursing center is comprised of the advisory and exacutive commitee; the advisory commitee serves consultants and links community needs to the nursing center, while the director of the exacutive commitee identifies the potential resources to generate funds, support, and facilitate the activities of staffs in a nursing center. Nursing centers mobilize various financal resources for reimbursement of services from college and insurance companies, collect minimum service fees from the client, and further collect fees for providing programs to community groups, this also includes membership fees, and donations. The services provided by nursing centers focus on services related to primary prevention, health maintenance & health promotion, direct nursing care for acute & chronic diseases, and holistic care for actual and potential health problems. The client satisfaction for the services was high. Students also showed positive reponses for their clinical experiences and independent working conditions. 2. The degree of knowledge, attitudes, and practices for breast cancer. and an individual's intention to participate in the BSEE program. The subjects of this study were 308 females in K-city in the Republic of Korea. Data were collected using a self-administered questionnaire. The mean age of the respondents was 35.0 years old. Those who already participated in the BSEE were 64.9%, and those who had support and encouragement to practice BSE from significant others were 25.1 %. Clients intent to participate in the BSEE were 37.0%. The mean score of knowledge(2.4 out of 5 points) and practices(1.8 out of 5 points) for breast cancer were quite low, but the mean score of attitudes was relatively positive04.5 out of 20 point) for breast cancer. Those who already had BSEE showed significantly high scores in knowledge(t=6.48, p<0.01), attitudes (t=10.54, p<0.01). and practices(t=57.07, p<0.001) for breast cancer than those who had not participated in the BSEE. In all age groups no intention to participate in the BSEE was higher than who the intention to participate. These findings suggest some strategies should be developed to increase the awareness of breast cancer's early detection.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.1
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• pp.34-38
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• 2017

Myelophycus simplex Papenfuss, a type of brown algae, is known to be majorly distributed in along the southern coast of Korea and Japan. The purpose of this study was to investigate the effects of M. simplex Papenfuss methanol extract (MSPME) on melanogenesis in ${\alpha}$-melanocyte-stimulating hormone-stimulated B16F10 melanoma cells. Melanin contents of B16F10 melanoma cells were decreased by 27, 41, and 59% in a dose-dependent manner, upon MSPME treatment at 100, 300, and $500{\mu}g/mL$, respectively. Tyrosinase activities in B16F10 melanoma cells were decreased by 18, 49, and 61% in a dose-dependent manner, upon MSPME treatment at 100, 300, and $500{\mu}g/mL$, respectively. MSPME suppressed expression of tyrosinase, tyrosinase-related protein-1, tyrosinase-related protein-2, and melanocyte-inducing transcription factor in B16F10 melanoma cells. Concentration of $50{\mu}g/mL$ of MSPME especially induced greater decreases in tyrosinase activity, melanin contents, and melanogenic enzyme protein expressions. This results indicate that MSPME inhibits melanin synthesis and tyrosinase activity, and M. simplex Papenfuss extract may be an ideal candidate as a skin whitening agent.

• The korean journal of orthodontics
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• v.31 no.3 s.86
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• pp.335-346
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• 2001

The purpose of this study was to investigate the ideal clinical torque(In the SWA rectangular wire, the torque by the angle between the plane part and twisted part to move the tooth) of the orthodontic rectangular wire which produce the proper labiolingual movement of the single tooth during finishing stage of the orthodontic treatment. The clinical torque is the sum of the play and the active torque which generates the moment at the bracket. The play is calculated by the formula and the active torque is calculated by the computer aided three-dimensional finite element method. The finite element model was consist of the three brackets which formed a row and 3 kinds of orthodontic rectangular wire(stainless steel, TMA, NiTi) which inserted in brackets. Both sides of the model were twisted and the moment generated in the center bracket was calculated. The sizes of seven wires which were used commonly were .016'X.022', .017'X.022', .017'X.025', .018'X.025', .019'X.025', .020'X.025', .021'X.025'. In 018' bracket, 016'X.022', .017'X.022', .017'X.025' wires were inserted and in 022' bracket, all the sizes of wires except .016'X.022' were inserted and tested. The following conclusions could be drawn from this study. 1. The moments generated on the same size of the wires by the same active torque were equal regardless of the bracket slot size. 2. The moments were increased with the size of the wires. The moment generated on the .021'X.025' wire was about 1.75 times as large as that on the .016'X.022' wire regardless of the material. 3. The moments were increased in the order of the NiTi, TMA stainless steel. The moment of the TMA wire was 0.35 times as small as that of the stainless steel wire and the moment of the NiTi was0.16 times as small as that of the stainless steel wire. 4. The moment was decreased as the interbracket distance was increased. 5. To get a desired moment with the specific size and material of the wire on the specific bracket slot, the formula and the results were displayed.

• Journal of Oral Medicine and Pain
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• v.32 no.4
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• pp.365-373
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• 2007

Destruction of oral soft and hard tissues and resulting problems seriously affect the life quality of xerostomic patients. Although artificial saliva is the only regimen for xerostomic patients with totally abolished salivary glands, currently available artificial salivas give restricted satisfaction to patients. The purpose of this study was to contribute to the development of ideal artificial saliva through comparing viscosity and wettability between CMC solutions and human saliva. Commercially-available CMC is dissolved in simulated salivary buffer (SSB) and distilled deionized water (DDW). Various properties of human whole saliva, human glandular saliva, and a CMC-based saliva substitutes known as Salivart and Moi-Stir were compared with those of CMC solutions. Viscosity was measured with a cone-and-plate digital viscometer at six different shear rates, while wettability on acrylic resin and Co-Cr alloy was determined by the contact angle. The obtained results were as follows: 1. The viscosity of CMC solutions was proportional to CMC concentration, with 0.5% CMC solution displaying similar viscosity to stimulated whole saliva. Where as a decrease in contact angle was found with increasing CMC concentration. 2. The viscosity of human saliva was found to be inversely proportional to shear rate, a non-Newtonian (pseudoplastic) trait of biological fluids. The mean viscosity values at various shear rates increased as follows: stimulated parotid saliva, stimulated whole saliva, unstimulated whole saliva, stimulated submandibular-sublingual saliva. 3. Contact angles of human saliva on the tested solid phases were inversely correlated with viscosity, namely decreasing in the order stimulated parotid saliva, stimulated whole saliva, unstimulated whole saliva, stimulated submandibular-sublingual saliva. 4. Boiled CMC dissolved in SSB (CMC-SSB) had a lower viscosity than CMC-SSB (P < 0.01 at shear rate of $90s^{-1}$). 5. For human saliva, contact angles on acrylic resin were significantly lower than those on Co-Cr alloy (P < 0.01). 6. Comparing CMC solutions with human saliva, the contact angles between acrylic resin and human saliva solutions were significantly lower than those between acrylic resin and CMC solutions, including Salivart and Moi-Stir (P <0.01). The effectiveness of CMC solutions in terms of their rheological properties was objectively confirmed, indicating a vital role for CMC in the development of effective salivary substitutes.

• Tuberculosis and Respiratory Diseases
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• v.60 no.1
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• pp.44-48
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• 2006

Background : Isoniazid (INH) is one of the most effective anti-tuberculosis (TB) drugs. In Korea, the dose of INH normally used in patients over 50 kg is 400 mg/day, which differs from the dose recommended by other countries. Indeed, the metabolism of INH shows ethnic variations, and Koreans are predominantly rapid acetylators. However, two reports suggested 300 mg of INH might be sufficient to reach an ideal peak level in Korean patients over 50 kg. Therefore, the aim of this study was to compare the effectiveness and adverse reactions between INH 300 mg and 400 mg in Korean TB patients. Method : Patients who were culture-positive, susceptible to all 1st-line drugs, initially on HREZ, and weighed over 50 kg were selected from patients with pulmonary TB between April 2003 and March 2005. The treatment results and adverse reactions in the INH 300 mg and 400 mg group were compared. Since April 2004, most TB patients at Asan Medical Center were administered INH 300 mg irrespective of the body weight. Results : The study included 123 patients in the 300 mg INH group and 128 in the 400 mg INH group. There were no significant differences between the groups in terms of age, gender, weight, history of TB treatment, initial smear strength, and frequency of cavitary lesions. There was no difference in the treatment duration between the groups. One hundred eleven (90%) patients in the INH 300 mg group and 102 (80%) in the INH 400 mg group completed treatment (p>0.05). There were no differences in the frequency of modification of the initial regimen between groups due to any adverse reactions (300 mg : 9.0%, 400 mg : 13.7%) and hepatotoxicity (300 mg : 2.7% ; 400 mg : 7.8%). Conclusion : Considering treatment results and adverse reactions of two groups, 300mg of INH may be sufficient for treating Korean TB patients. Further studies comparing the frequency of relapse will be needed.

• Journal of Chest Surgery
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• v.32 no.1
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• pp.1-4
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• 1999

Background: The transplantation of organs between phylogenetically disparate or harmonious species has invariably failed due to the occurrence of hyperacute rejection or accerelated acute rejection. But, concordant cardiac xenograft offer us an opportunity to study xenotransplantation in the absence of hyperacute rejection. Current therapeutics for the prolongation of survival of rodent concordant xenotransplantation are not ideal with many regimens having a high mortality rate. Cyclosporine A & Mycophenolate Mofetil are new immunosuppresive agent which has been shown to be effective at prolonging survival of allograft, as purine synthesis inhibitor. Material and Method: We used white mongrel rats as recipient and mice as donor, divided 4 groups(n=6), control group(Group 1) has no medication or pretreatment, Group 2 has splenectomy as pretreatment 7∼10 days before transplantation, Group 3 has Cyclosporine A treatment group, Group 4 has combined treatment of Cyclosporine A & Mycophenolate Mofetil(RS 61443). We compared survival time. Reuslt: We can't find significant difference of survival time between each groups. Conclusion: We concluded that rejection of cardiac xenograft was different from rejection of allograft, and new immunossuppresive Agent(Mycophenolate Mofetil, Cyclosporine A) was not effective for prolongation of survival time after cardiac xenograft.