사립체 DNA 뉴클레오타이드 3243 A→G 돌연변이 [MTTL1^*MELAS3243G]에 의한 MELAS 증후군

박기형,김승현,이영주,김희태,김주한,김명호,박성섭 대한신경과학회 1998 대한신경과학회지 Vol.16 No.4

곰팡이에서 분리한 Helicobacter pylori 항균물질의 분리 및 구조규명

남궁준,연승우,백남수,김태한,김영호,김창진,김기원 충남대학교 약학대학 의약품개발연구소 1998 藥學論文集 Vol.14 No.-

Helicobacter pylori is a Gram-negative bacterium which causes chronic gastritis and is associated with gastric ulcer, duodenal ulcer and gastric carcinoma. In the process of screening of antibacterial activities against H. pylori from soil microorgani는, fungus No. 60686 was isolated. After fementaion of No. 60686, the antibacterial compound was isolated, purified and followed by extraction of mycelium with orgainic solvents, acetone and ethyl acetate, through silica gel chromatography, LH-20 gel chromatography and HPLC. As a result of the structural analyses of the compound by IR, ^1H- and ^13C-NMR, FAB/Mass spectrophotomer, the compound having the antimicrobial activity was idenfitied as chaetoglobosin A (C_32H_36N_2O_5), a cytochalasan derivative. The antimicrobial activity of chaetoglobosin A was tested against Gram-positive and negative bacteria by paper disk method. Among the test strains of 9 Gram-positive bacteria and 18 Gram-negative bacteria containing 4 H. pylori strains, the growth of 4 H. pylori strains and 3 S. aureus strains (SG 511, 285 and 503) was only inhibited by chaetoglobosin A. Also it was shown that its growth inhibition against H. pylori strains was stronger than that against S. aureus strains at the treatment of the same concentration. Therefore it was concluded that chaetoglobosin A has a specific growth inhibition against H. pylori of the tested bacteria.

학국에서 심방세동의 임상양상에 관한 연구

이선미,조정휘,홍순조,최윤식,안신기,김성순,김영훈,김윤년,조정관,차태준,김유호,최기준,김준수,이상민,신동구 대한순환기학회 2000 Korean Circulation Journal Vol.30 No.5

패킷손실 감소를 위한 PIM-SM에서의 임계치 분석

金太奐,金太勳,朴惠蓮,李基鉉 明知大學校 産業技術硏究所 2003 産業技術硏究所論文集 Vol.22 No.-

Abstract - Recently, the IP multicast providing point-to-multpoint delivery has received wide concerns due to the ever increasing applications based on it, such as video on demand, IP broadcasting service, and so on. However, most of the exiting multicast protocols have a scalability problem in which the network performance degrades as the increase of the network size. Among the existing protocols, the Protocol Independent Multicast(PIM) protocol has been known as one the effective protocols that handles the scalability problem. Especially, the PIM-SM is more suitable for the realistic situation of the current Internet. The purpose of this paper is to examine the effect of this threshold value on the network performance in respect of the packet loss for a variety of network topologies.

Salmonella sp.의 신속한 동정을 위한 증진배양의 개선에 관한 연구

김기태,김태우,옥순학,이영호,백운화 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.6

식품 및 생활폐수내의 존재하는 Salmonella spp.에 대한 효율적이고 신속한 동정을 위한 증진배야업을 개발하고자 하였다. 본 연구에 사용된 균주인 S. enteritidis 생육을 촉진시키기 위한 방법으로 cAMP 및 yeast extract를 사용하였는데 전자인 경우는 배지내의 농도가 10 mM 이상일 때 10^-3 cfu/ml의 균수로 7시간 배양후 균수가 control보다 약5배의 증가를 보였으며 후자인 경우는 0.6% 첨가시 10배의 증가를 보였다. 다른 균주들에 대한 선택적인 성장효과를 보기위하여 selenite broth와 bile salts를 사용하였고 이때 사용된 균주는 Staphylococcus aureus, Pesudomonas aeruginosa, Lactobacillus plantarum 및 Escherichia coli이었고 bile salts의 농도가 0.1%일때 네 가지 균주의 증식에 대한 억제 효과가 있었다. 두 단계의 증진배양법으로서 1차 증진배양에서는 selenite broth에 0.6% yeast extract를 첨가한 것으로 2차 증진배양에서는 0.1% bile salts를 첨가한 것으로 하였는데 타균과의 혼합배양에서 Salmonella의 초기균수가 10^0.3일 때 14시간 증진배양으로 10^8.5 cfu/ml까지 증식을 보였으며 초기균수가 1 cfu/100 ml인 경우는 10시간의 1차 증진배양과 6시간의 증진배양으로 약 10^7의 증식속도를 나타내었다. The development of an enrichment method for the rapid and effective identification of Salmonella spp. in sewage or food was studied. As a growth factor for Salmonella, 10 mM cyclic adenosine monophosphate (cAMP) in trypticase soy broth with 0.6% yeast extract (TSBYE) increased cell number five-folds and 0.6% yeast extract in selenite broth increased cell number ten-folds of control. Bile salts in slenite broth was tested for the selection of S. enteritidis in a mixture with Staphylococcus aureus, Pesudomonas aeruginosa, Lactobacillus plantarum and Escherichia coli. The latter four strains were effectively inhibited at 0.1% bile salt. A two-step culture method was used to enrich Salmonella spp.; a primary-enrichment and secondary-enrichment culture. At a primary-enrichment step, selenite broth with 0.6% yeast extract and 10 mM cAMP was used, and at a secondary-enrichment step, -0.1% bile salt was additionally used. Culture times of a primary-enrichment and a secondary-enrichment step were 8 hr and 6 hr, respectively. In this procedure, cell number increased from 10^0.3 to 10^8.5 with inhibition of other strains within 14 hr. In the case of an initial cell concentrarion as low as 10^-2 cfu/ml, a cell number increased to 10^7 cfu/ml by using a 10 hr primary-enrichment and 6 hr secondary-enrichment procedure.

와인딩 공정에서 접압롤의 동특성에 관한 연구

김성수,김규태,천성민,신기현 건국대학교 산업기술연구원 1997 건국기술연구논문지 Vol.22 No.-

In a web winding process, the contact roll plays many important roles in air entrainment control and WIT(Wound In Tension) regulation. The behavior of the contact roll significantly affects the winding tension characteristics specifically at the time of contact and separation when the tangential velocities of contact roll and winding roll are not synchronized. A new mathematical model which includes the behavior of the web tension, the winding roll, the carriage and the contact roll is derived for the control of the winding tension. By using the model derived, a non-linear PID(NPID) controller is designed to control the winding tension at the time of contact and separation between the contact roll and the winding roll. Computer simulation study showed that the performance of the winding system with the NPID controller was significantly improved compared with that of a system with PID controller.

기저세포암, 피부전이암과 유사한 조직소견을 보인 안검 외 피지선암 1예

김상태,노효진,서기석 고신대학교의과대학 2008 고신대학교 의과대학 학술지 Vol.23 No.1

Backgroud : Extraocular sebaceous carcinoma is a malignant tumor derived from the adnexal epithelium of sebaceous glands. A poorly differentiated sebaceous carcinoma shows variable histopathologic findings and mimics other primary tumor and cutaneous metastases mostly composed of clear cells. Case : Our patient consultation was requested for a 53 year?old female with solitary mild painful tumor on the scalp. The first histopathlogic impression of this case was basal cell carcinoma on the other hospital. After reevaluation, our diagnosis is not basal cell carcinoma but extraocular sebaceous carcinoma. Conclusion : A thorough exact recognition of characteristic histopathologic features of extraocular sebaceous carcinoma is necessary for making diagnosis, treatment plan and determining the prognosis.

Amalgambond Liner의 도포가 amalgam 수복재의 변연누출과 유지력에 미치는 영향에 관한 연구

김태성,김종수,김용기 大韓小兒齒科學會 1996 大韓小兒齒科學會誌 Vol.23 No.4

In this study, we tried to evaluate the effect of Amalgambond liner application on the degree of marginal leakage and retention of amalgam restoration by comparing with that of the Copalite and All-bond 2. The results obtained from this experiment were as follows; 1. Tensile strength representing the bond between amalgam and tooth structure was the highest in Amalgambond, and All-Bond 2, Copalite in descending order. There were statistically significant difference between each group(P<0.05). 2. The degree of microleakage in Amalgambond was lower than that of All-Bond 2, and Copalite, but no stastically significant difference could be found(P>0.05). 3. The liner such as Amalgambond or All-Bond 2 were evaluated to be superior to the conventional Copalite in bond strength as well as in microleakage. But the result of this study could not show the superiority of one material over the others; Amalgambond and All-bond 2.Besides the results of the study, other factors, such as practical convenience. should be considered in determining the selection of material. The support of well-designed clinical studies on this subject are in demand.

이동환경에서 RFID 단말 시스템의 설계 및 구현

김태환,홍원기,이용두 대구대학교 정보통신연구소 2004 情報通信硏究 Vol.3 No.2

RFID는 태그와 리더간 전자기 유도를 통해 객체를 식별하는 무선 통신 기술이다. 이는 객체를 식별하기 위한 인식 거리나 위치 등에 있어서 바코드에 비해 매우 자유로우며 동시에 여러 객체를 인식 할 수 있기 때문에 향후 물류, 유통 산업에서 높은 기술적 가치를 갖는다. 일반적으로, 리더기를 통해 식별된 객체에 대한 상세한 정보를 얻어내기 위해 PML 서버로부터 해당하는 정보를 검색, 추출하기 위한 과정이 요구된다. 그러나 이것은 많은 연산과 서버와의 통신을 요구하기 때문에 자원 제한적인 리더기에는 상당한 부담이 될 수 있다. 본 논문에서는 제한적인 하드웨어 자원을 가진 리더기에서 PML 문서 검색, 추출을 위한 부하를 줄이기 위한 시스템을 제안한다. RFID (Radio Frequency IDdentification) is a wireless communication technology that identifies an object containing a tag through electromagnetic induction. Because it is not restricted in its position or the read range as much as the bar code technology which requires a line-of-sight to identify an object but also able to read several tags at the same time, it is considered to be one of the promising technologies used in the distribution industry in the future. Generally, a process of retrieving and acquiring a corresponding data should be needed to get a detail information about an object identified by a RFID reader. However, it gives a heavy burden on the resource-restricted reader because it requires significant computation and communication tasks. This paper proposes a 글로벌 RFID system that efficiently decreases the computation load to retrieve an acquire a PML document for the resource-restricted reader.

치수 치근단 병소의 전구 위험요인으로서의 제 2 형 당뇨의 역할에 관한 소고

김진희,배광식,서덕규,홍성태,이윤,홍삼표,금기연 大韓齒科保存學會 2009 Restorative Dentistry & Endodontics Vol.34 No.3

Diabetes Mellitus (DM) is a syndrome accompanied with the abnormal secretion or function of insulin, a hormone that plays a vital role in controlling the blood glucose level (BGL). Type 1 and 2 DM are most common form and the prevalence of the latter is recently increasing. The aim of this article was to assess whet her Type 2 DM could act as a predisposing risk factor on the pulpo-periapical pathogenesis. Previous literature on the pathologic changes of blood vessels in DM was thoroughly reviewed. Furthermore, a histopathologic analysis of artificially-induced periapical specimens obtained from Type 2 diabetic and DM-resistant rats was compared. Histopathologic results demonstrate that the size of periapical bone destruction was larger and the degree of pulpal inflammation was more severe in diabetic rats, indicating that Type 2 DM itself can be a predisposing risk factor that makes the host more susceptible to pulpal infection. The possible reasons may be that in diabetic state the lumen of pulpal blood vessels are thickened by atheromatous deposits, and microcirculation is hindered. The function of polymorphonuclear leukocyte is also impaired and the migration of immune cells is blocked. leading to increased chance of pulpal infection. Also, lack of collateral circulation of pulpal blood vessels makes the pulp more susceptible to infection. These decrease the regeneration capacity of pulpal cells or tissues, delaying the healing process. Therefore, when restorative treatment is needed in Type 2 DM patients, dentists should minimize irritation to the pulpal tissue under control of BGL. 당뇨(Diabetes Mellitus)란 혈당을 조절하는 인슐린의 분비나 기능에 장애를 야기하는 질환으로 인슐린 의존성 여부에 따라 제 1 형과 제 2 형으로 분류된다. 본 종설은 최근 증가 추세에 있는 제 2 형 당뇨가 치수 치근단 병소의 병인 과정에 전구 위험 요인으로 작용할 수 있는지를 평가 하고자 문헌고찰을 통해 당뇨의 병인 과정에서 특징적으로 나타나는 혈관 합병증에 관해 알아보고, 부가적으로 제 2 형 당뇨 쥐 모델에서 인위적인 치수감염 후 얻은 치근단 조직의 조직병리학적 분석을 시행하였다. 조직학적 관찰 결과 제 2 형 당뇨 쥐에서 대조군에 비해 치수 치근단 병소의 크기가 증가하였고, 치수 염증 반응도 심하게 나타난 것으로 보아 당뇨 자체가 숙주를 감염에 취약한 상태로 만드는 전구 위험요소로 작용하였음을 알 수 있었다. 이러한 이유로는 첫째, 당뇨 시 전반적으로 나타나는 혈관 내 죽상 침착(atheromatous deposits)에 의해 혈관 내벽의 두께가 두꺼워져 미세 순환의 장애는 물론 탐식 세포의 기능 저하, 면역 세포의 혈류 이동이 차단되어 치수 감염 시 쉽게 치근단 병소로 이환될 가능성이 높고, 둘째 치수 혈관에서 특징인 측부 순환(collateral circulation)의 부재에 따른 살균성 다형핵 백혈구의 활동 억제를 포함한 미세 혈관계의 취약성으로 인해 치수 조직의 재생능이 저하되어 추가적인 감염원의 공격에 대한 방어 및 치유 저하를 더욱 심화시키기 때문인 것으로 사료된다. 따라서 제 2 형 당뇨 환자의 수복치료 시 치과의사는 당뇨 조절 하에서 치수 조직의 자극을 최소화하기 위한 세심한 처치가 필요하다.