이동통신 멀티미디어 데이터서비스의 트래픽 특성 모델링 및 성능분석

정용주,백천현,김후곤,최택진,양원석,황흥석 한국경영과학회 2003 한국경영과학회지 Vol.28 No.2

The aim of this study is to identify the data traffic capacity of 3G mobile communication networks, especially of cdma2000-1X networks. Three-layered ON/OFF traffic model is used to describe the dynamics of data traffics and the process of data transmission such as packet scheduling. We construct a simulator fully incorporating packet handling process of cdma2000-1X data network as well as three-layered ON/OFF traffic model describing the behavior of source data traffics. To get influence of traffic parameters on performance measures, the extensive simulations were performed for several data sets which are obtained from real trace data or previous studies. The experimental results show that the engineered throughput satisfying QoS criteria is approximately 20% of total capacity. Finally, some proposals to improve the system capacity are followed.

음악적 재능과 성격적 특징

정진우,박제경,염택구 최신의학사 1973 最新醫學 Vol.16 No.1

Malathion이 Mouse 肝細胞의 微細構造에 미치는 影響

鄭鎬三,李圭植,金振宅 한양대학교 의과대학 1985 한양의대 학술지 Vol.5 No.1

Malathin (0,0-dimethyl 5-[1,2 dicarboethoxyethyl] dithiophosphate) is one of the organic phosphorus compounds and has been widely used as an insecticide. It is well known that the organophosphorus compounds inactivate an enzyme, cholinesterase, and resultant accumulation of acetylcholine effects on a pattern of cholinergic stimulation. Present study has demonstrated the hepatotoxicity caused by malathion, an organophosphorus compound, observing the ultrastructural changes in the cytoplasmic organelles of hepatocytes in mice. The experimental animals were given 0.2ml of malathion diluted in olive oil(100mg/kg) by intraperitoneal injection. The animals of control group were killed at 6 hours after olive oil treatment, and the animals of the experimental groups were killed at 12, 24 and 36 hours after administration of malathion, respectively. The specimens obtained from the left anterior lobes of the liver were stained with uranyl acetate and lead citrate double contrast methods and observed with JEM 100B model electron microscope. The cytoplasmic organelles of hepatocyte in malathion trated mice showed the fallowing significant changes. 1) A slight morphological changes such as dilatation, sacculation and fragementation of the cisternae of rough endoplasmic reticulum associated with detachment of membrane-bound ribosomes and disaggregation of the free ribosomes are recognized. 2) Primary lysosomes were increased in number and formation of secondary lysosomes (autophagic vaculoes and residual bodies) were observed. 3) The smooth endoplasmic reticulum associated with depletion of the glycogen particles were noted. 4) Large amount of lipid droplets were originated. The results obtained in the present study suggested that malathion appeared to by cytotoxic to the liver cells of mice and that the organophosphorus compound would induce retrograde changes characterized by destruction of small organelles of the hepatocytes.

어린 가토에서 자가 연골 이식후 연골성장에 관한 실험적 연구

권택근,김태연,정전은,이동진 대한성형외과학회 1992 Archives of Plastic Surgery Vol.19 No.3

Does free transplanted autologous cartilage grow? Until now many autors have published different results about the growth potential of cartilage. Some authors have produced in their study that transplanted cartilages were able to grow, but others showed contradicting results. In this study, authors obtained cartilages from young rabbits'ear, 10 by 10mm in size and divided them into two groups ; the first group was cartilages with perichondrium and the second group was cartilages stripped perichondrium. We transplanted both groups of cartilages in the posterior nuchal area of rabbits. Then numbers of specimens of each group were evaluated and compared for assessment of cartilage growth. After observaton for six months, we took the cartilages from the posterior nuchal area and examined the surface area, the thickness, and the weight and finally confirmed the growth potential of the cartilage by histologic study. The results are as follows : 1, The surface area, the thickness, and the width of the transplanted cartilages were increased significantly in gross specimens and their measured values were statistically significant and cartilages with perichondrium showed more growth than cartilages stripped perichondrium 2. In histologic studies, we observed increased surface activities with numerous proliferatng cells and found no abnormal features compared with normal cartilages. Cartilages with pericondrium were thicker than cartilages with stripped perichondrium

초내식성 스테인리스강 선재와 브라켓의 내식성 및 금속 이온 용출 특성

오근택,정경진,황충주,박용수,김경남 大韓齒科器材學會 2001 대한치과재료학회지 Vol.28 No.4

Metallic orthodontic appliances are known to release metal ions in an oral cavity. It is not advisable that toxic corrosion products derived from the appliances is absorbed into the body. Metal ions release from orthodontic appliances is known to have large effects on the result of orthodontic treatment and systemic health. Metal bracket and wire were made of super stainless steel(S32050) with high corrosion resistance. The corrosion resistance and ion release property of S32050 and conventionally used appliances were examined. Four types of wire were ligated in either super stainless steel(SB) or Tomy bracket(TB) with O-ring, and then each group was immersed in an artificial saliva at 37℃ for 12 weeks. Amount of released metal ions was measured with immersion time by graphite furnace atomic absorption spectroscopy and surface morphology was investigated. S32050 showed the low passive current density of about 1 μA/㎠ and the stable passive region to a high potential in artificial saliva. S32050 appliances did hardly release nickel ions in artificial saliva. S32050 wire(SRW) and NiTi wire(NW) didn't show significant difference of Ni ion release with immersion time, meanwhile, Remanium wire(RW) showed significant difference in 12 weeks. Ni ion releasce from the brackets didn't show any significant difference with immersion time and between SB and TB. Amounts of Ni ion released from TB-SRW showed significant difference in 12 weeks, those from TB-RW showed significant difference from 4 weeks later and highest release among all groupsin12weeks. TB-NW released little Ni ion for all immersion time and showed significant difference from 4 weeks later, TB-TW(TMA wire) showed significant difference in 12 weks. SB-SRW didn't show any significant difference and SB-RW signigicant difference in 12 weeks,but lower compared with TB group. SB-NW and SB-TW didn't show any significant difference. Corrosion products didn't be observed in mostly groups during the immersion time, except that in TB-RW, they were observed on the bracket surface between O-ring and wire from 8 weeks later. Super stainless steel wire had good corrosion resistance compared with stainless steel wire, and it is believed that it can be used as orthodontic material for bracket and wire.

알러지성 접촉피부염 유발 피부 주변 림프절에서의 세포성 면역 활성에 관한 면역조직화학적 연구 : T 림프구와 IL-2 수용기의 분포 변화를 중심으로 Based on the change of T lymphocytes and Il-2 receptors

김진택,안상현,박인식,정재만,김호현 동국대학교 한의학연구소 1998 東國韓醫學硏究所論文集 Vol.7 No.1

본 연구는 알러지성 접촉피부염(allergic contact dermatitis) 유발 피부 주변 림프절에서의 세포성 면역활성으로 나타나는 면역조직화학적 형태변화를 조사하기 위해 DNCB로 인위적인 알러지성 접촉피부염을 BALB/C계 생쥐의 샅바위부분 피부에서 유발시킨 후 시간 경과에 따른 샅바위 림프절(inguinal Iymph node)에서의 T 림프구와 IL-2 수용기의 분포변화를 관찰하였다. 대조군에서는 L3T4(CD4)에 양성반응을 보이는 도움 T 림프구, Ly2(CD8)에 양성반응을 보이는 세포독성 T 림프구 그리고 CD25R에 양성반응을 보이는 IL-2 수용기를 가진 세포는 곁피질(paracortex)과 수질동(medullary sinus)에서 분포하였다. DNCB에 의한 알러지성 접촉피부염 유발후 24시간부터 도움 T 림프구, 세포독성 T 림프구 그리고 IL-2 수용기를 가진 세포가 곁피질과 수질동에서 증가하기 시작하여 48시간에 이르러서는 그 분포와 양성반응성이 최고에 달했다. 48시간의 이러한 분포는 수질동에서 잘 나타났으며, 특히 세포독성 T 림프구가 많은 증가를 보였다. 72시간에 이르러서는 양성반응세포가 서서히 감소되는 것으로 나타났지만, 대조군에 비해서는 여전히 증가된 분포양상으로 나타났다. 이상의 결과로 미루어보아 DNCB에 의한 접촉성 피부염 유발시 림프절에서는 도움 T림프구의 분열·활성 증대로 인한 IL-2 생성·분비 증가의 결과 세포독성 T 림프구의 분열·활성 유도하는 일련의 세포성 면역연쇄반응의 활성이 일어나게 된다. 이러한 세포성 면역연쇄반응의 활성은 주변 피부에서 일어나는 알러지성 접촉피부염으로 인한 피부손상을 주도하는 것으로 사료된다. Lymph node tissues of BALB/C mouse treated with DNCB were immunohistochemically observed to investigate the activation of cell mediated immunity in Iymph node of murine with allergic contact dermatitis. The inguinal region of BALB/C mice were sensitized by one application of 25㎕ of 5% 2,4·-dinitrochlorobenzene(DNCB) onto an abdominal skin and 2 weeks later, the mice were challenged with 4㎕ of 2.5% DNCB. The inguinal lymph node were obtained at hour 24, 48, and 72 after 2nd DNCB treatment and embedded with paraffin, and then stained by following ABC method that used monoclonal antibody including L3T4(CD4), Ly2(CD8), IL-2R(CD25). The distribution of helper T lymphocytes, cytotoxic, T lymphocytes and IL-2 receptors began to increase at hour 24 after 2nd DNCB treatment and these increase appeared in paracortical area and medullary sinius. These increase were greatest at hour 48. These results indicated that the IL-2 secretion began to increase by activation of helper T lymphocytes in lymph node of DNCB re-exposure area and subsequently to activate suppress T lymphocytes.

식이섬유 보충 음료의 섭취와 규칙적 운동에 따른 비만관련 체구성 요인 및 혈중 요인의 변화

임용택,김성수,윤성진,강선영,김재등,박인성,권순욱,이충영 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.3

The purpose of this study was to investigate the effect of drink including dietary fiber supplementation and regulatory exercise on body composition and blood profile concerning obesity of women. Twenty young healthy but on mild obesity women were participated as a subject, Body composition and blood profile were measured before and after 6 weeks' supplementation and exercise, The results of this study were as follows: First, Body composition concerning obesity such as body weight(p=.0001) and %body fat(p=.0001) after 6weeks' dietary fiber supplementation and exercise was decreased significantly. Second, blood profile concerning obesity such as TC(p=.0001), LDL-C(p=.0001) and TG(p=.0002.) after 6weeks' dietary fiber supplementation and exercise was decreased significantly. This results suggested that drink including dietary fiber supplementation and regulatory exercise should be recommended as a effective method for cure and prevention obesity.

pHOxsFV벡터와 배아주간세포를 이용한 형질전환생쥐 생산 기초연구

이훈택,이봄이,정길생,김진회 건국대학교 동물자원연구센터 1998 動物資源硏究誌 Vol.19 No.-

pHook™-1 hapten 4-ethoxy-methylene-2-phenyl-2-oxazolin-5one(phOX)의 단일 항체 sFV를 암호화 하고 있으며, murine의 Ig k-chain V-J2-C 영역유래의 signal peptide에 의하여 항체를 세포 표면에 배열시키도록 고안되어 있다. 또한, 항체를 세포막 바깥쪽에 부착되어 있도록 하기 위해 PDGFR 유래의 transembrane domain의 C 말단에 결합되어 있다. 이렇게 고안된 vector을 발현하는 세포는 세포막에 sFV을 발현함으로, phOX로 코팅된 자석베드를 이용하여 배양체로부터 목적의 유전자를 발현하는 세포만을 분리할 수 있을 것이다. 따라서, 본 연구는 pHook™-1 유전자를 co-transfection함으로써 목적의 유전자를 가진 배아주간세포를 단시간 내에 효율적으로 선발하기 위하여 실시하였다. 또한, 배아주간세포에서 목적의 DNA 발현 또는 존재를 검증하기 위해 DNA 발현 또는 존재를 검증하기 위해 PCR 방법과 조직화학적 방법을 사용하였다. 형질전환유전자 발현을 transfection(유전자 전이) 후 4∼14일 사이에 모든 배아주간세포에서 확인되었다. Magnetic bead를 이용하여 선발된 세포에서 co-transfected DNA는 배아주간세포에서 효율절으로 삽입되었으며, 선발된 세포의 약 90%는 co-transfected 유전자를 발현하였다. 이 결과는 세포생리학에서 특이 유전자의 급성변이와 만성변이를 연구하거나, 또는 형질전환동물을 생산하기 위해 pHook™-1 목적유전자와 함께 전이함으로서 효율적으로 목적의 유전자를 가진 세포를 선발 가능함으로써 보다 간편하게 형질전환도 동물의 생산에 이용 가능하다는 사실을 확인하였다. pHook™-1 encodes a single-chain antibody(sFv) directed toward the hapten 4-ethoxy-methylene-2-phenyl-2-oxazolin-5-one(phOx): the signal peptide from the murine Igk-chain V-J2-C region is fused in front of coding region of the sFv to direct the antibody to the plasma membrane. The antibody is fused at the C-termius to the transmembrane domain from the platelet derived growth factor receptor(PDGFR), allowing the antibody to be anchored and displayed on the extracellular side of theemmbrane. Transfected cells expression sFv can be isolated from whole cultures by using magnetic coated with phOx and a strong magnetic strand. Thus, the present study was designed to apply the embryonic stem cells by using pHook™-1 . Cell-transduction efficiency was measured by morphometric analysis. Polymerase chain reaction and histochemistry were used to detect the presence and/or expression of objective DNA in embryonic stem cells. Transgene expression was detected in all cases between 4 and 14 day after transfection. In selected cells using magnetic bead, co-transfected DNA was also incorporated efficiently in embryonic stem cells and approximately 90% of the selected cells expressed co-transfected gene. This result suggested that this selection system can be used as a feasible tool, when pHook™-1 is cotransfected with objective gene, to isolate and study for acute and chronic changes of a specific gene in cellular physiology.

유방암 환자에서 bcl-2 단백 발현의 예후 인자로서의 의의

류진우,박종권,정민,박동국,김정택,이두선,이찬영,전호진 단국대학교 1998 論文集 Vol.32 No.-

Breast cancer in women pose a problem, and it can be difficult at times to evaluate the possibility of the cancer recurrence in node negative early cancer. The reliable prognostic markers are needed in breast cancer management to help clinicians identify the patient with the high risk of recurrence and arrive at more rational decisions for proper treatment. In order to investigate the prognostic significance of bcl-2, an immunohis-tochemical staining was performed in 35 tissue sections from paraffin blocks of primary breast cancer. Bcl-2 positivity was 43%. No relation could be observed between bcl-2 expression and known prognostic factors(tumor size, lymph node metastasis state, histologic grade, and nuclear grade), There was strong relation between bcl-2 expression and estrogen receptor positivity (ER) (P〈0.05). No relation is found between bcl-2 expression and c - erbB - 2 expression. These results suggest that bcl-2 expression is associated with a favorable prognostic factor(ER) but it is of no value as independent prognostic factor to the clinician in identifying the patients with high risk of recurrence.

교정학적 적용을 위한 초내식성 스테인리스강의 특성

오근택,김금진,황충주,박용수,김경남 大韓齒科器材學會 2001 대한치과재료학회지 Vol.28 No.3

Various kinds of orthodontic appliances have been developed for ideal tooth movement during orthodontic treatment. The orthodontic appliances made of metals are bands, arch wires, brackets and miniscrews as orthodontic anchorage. Generally, these appliances are made of stainless steel, pure titanium, Ni-Ti and TMA with the proper biocompatibility. However, localized corrosion of these materials can frequently occur in the particular environment. Super stainless steels, recently developed, have good corrosion resistance to reduce metal ion release induced by many kinds of corrosion. Recently, it has been reported that nickel ion release from orthodontic appliances affect the prevalence of nickel sensitization; however, there has been some controversy about nickel hypersensitivity to orthodontic appliances containing nickel. The purpose of this study was to evaluate and compare the microhardness, nickel ion release, corrosion resistance and cytotoxicity of 4 types of super stainless steels and 316L stainless steel as the control group according to nickel contents, and to determine the acceptability as the new material for various kinds of orthodontic appliances. All super stainless steels showed higher microhardness than 316L stainless steel, SR-3Mo showed especially the highest microhardness. In anodic polarization test, corrosion resistance was high in order of SR-50A, SFSS, SR-6DX, 316L stainless steel, SR-3Mo. There was no increase in nickel ion release from SR-50A, SR-6DX, 316L stainless steel with immersion time in artificial saliva; whereas there was some increase from SFSS and SR-3Mo with immersion time. All super stainless steels showed very low cytotoxicity regardless of nickel contents although SR-3Mo showed relatively higher cytotoxicity than the others. It is concluded that SR-50A among super stainless steels has the highest corrosion resistance and biocompatibility. It is undesirable to consider the alloys with high nickel content to release lots of nickel ion.