상아질 전처리 방법이 상아질과 GLASS IONOMER CEMENT간의 결합강도에 미치는 영향에 대한 실험적 연구

정상백,임미경,동진근 원광대학교 치의학연구소 1992 圓光齒醫學 Vol.2 No.2

This is a study on the effect of the dentinal pretreatment method to the bond strength between dentin and glass ionomer cement. In this study, 196 human molar teeth with sound crown were used. The dentin surfaces of these teeth were exposed with wet trimmer and polished with #800 Emory paper and teeth were divided into 7 groups according to the pretreatment agent and method. Each group has 4 subgroups of the kinds of glass ionomers. The shear bond strength were measured by Instron Universal Testing Machine model 1122. The data of the evaluations were then subjected to statistical analysis using one way ANOVA and the results were as follows 1. In Durelon liquid 20 sec scrubbing & Vitrebond filling subgroup, shear bond strength was highest with mearsurements of 72.41(㎏/㎠) and in no pretreatment & Shofu lining cement filling subgroup, lowest with mearsurements of 4.77(㎏/㎠).

Streptococcus salivarius의 요소분해효소 활성에 관한 연구

정상백,최호영,민병순,박상진,이진용,최기운 大韓齒科保存學會 1998 Restorative Dentistry & Endodontics Vol.23 No.1

Dental caries is induced by organic acids produced by oral bacteria. In order to prevent dental caries, therefore, it is essential to maintain neutral pH in the oral cavity. Urea plays a major role in oral pH homeostasis. Urea is hydrolyzed by bacterial ureases to ammonia, causing a pH elevation, Streptococcus salivarius has been shown to be a major contribution to oral ureolysis. Synthesis of urease by S. salivarius appears to be constituitive, but can be greatly enhanced by low pH. It is, therefore, conceivable that ureolytic activity of S. salivarius from a carious lesion is greater than that of the bacterium from a healthy tooth. In the present study, urease activity of S. salivarius isolates from dental plaque of carious lesions was compared with that of the isolates from plaques of the teeth and the dorsum of the tongue; 45 S. salivarius strains were isolated from carious lesions(>C2) of 21 individuals with dental caries and 30 strains from 10 individuals without dental caries. The results were as follows: 1. All the 21 individuals with dental caries harbored ureolytic S. salivarius whereas 3 of 13 individuals without dental caries harbored non-ureolytic strains of S. salivarius. 2. All the 45 S. salivarius isolates from carious lesions showed urease activity. In contrast, of 30 isolates from individuals without dental caries, 17 isolates(56.7%) did not demonstrate urease activity, or if any, very little(<5μmol/min/mg). 3. Urease activity of the isolates from carious lesions was greater than that of the isolates from individuals without dental caries:the urease activity ranged from 42 to 381μmol/min/mg and from 0 to 208μmol/min/mg, respectively. 4. At acid pH(5.5), the isolates which showed intermediate urease activity at pH 7.0 demonstrated even higher activity whereas the isolate with no or lower urease activity did not show any significant difference in their activity. However, the isolates with the greatest urease activity from both individuals with and without dental caries, exhibited a rather much lower urease activity at pH 5.5. The overall results suggest that isolates may have their own urease activity but the isolates exposed to chronic acidic environment of the carious lesion might elevate urease activity of S. salivarius, which in turn, might influence on survival of S. salivarius itself and other bacteria establishing a new oral bacterial ecosystem.

양팔의 혈압 차이로 발견한 빗장밑 동맥 도루 증후군 (Subclavian Steal Syndrome)을 스텐트 삽입술로 치료한 환자 증례

김원백,오미경,이수희,김하경,김진영,노진,정상식,정승문 대한가정의학회 2009 Korean Journal of Family Medicine Vol.30 No.12

A case of successful correction of subclavian steal syndrome by percutaneous transluminal angioplasty with stenting in a male patient who found incidentally signifi cant interarm blood pressure difference. Small difference in blood pressure (BP) between two arms is a relatively common. Significant interarm BP difference is a potential marker of peripheral vascular disease such as subclavian artery stenosis and a predictor of cardiovascular disease. The subclavian steal syndrome is a condition that results from stenosis of subclavian artery proximal to the vertebral artery. The resulting symptoms are vertebrobasilar insuffi ciency symptoms due to reversal of blood flow from the contralateral vertebral and basilar artery into the ipsilateral upper extremity vessels and arm ischemic symptoms. Stenotic lesion of subclavian artery has traditionally been treated surgically. However recent trends are undergoing a paradigm shift from open surgery to endovascular approach. We report a patient with subclavian steal syndrome who found incidentally 35 ㎜Hg interarm systolic BP difference. It was successfully treated by percutaneus transradial angioplasty with stenting on stenotic lesion of the subclavian artery. 양팔의 혈압은 정상인에 있어서도 약간씩만 차이가 있을 수 있으나 그 차가 심할수록 동맥경화증으로 인한 빗장밑 동맥 의 협착을 비롯한 말초 혈관 질환을 시사하고, 심혈관계 질환 의 이환율과 사망률이 높아진다. 빗장밑 동맥 도류 증후군은 말초 동맥 질환의 일종으로 빗장밑 동맥의 협착으로 인하여 나타난 현상을 의미하며, 가장 흔한 원인은 동맥경화증이다. 증상은 뇌기저부 허혈 증상과 병변측의 상지 허혈증상으로 나타내고, 치료는 수술적 방법과 혈관 중재 시술을 통하여 혈 류를 재개한다. 저자들은 힘든 작업 후에 어지러움, 말이 꼬이 는 증상을 주소로 내원한 42세 남자 환자에서 양팔의 수축기 혈압이 차이가 35 ㎜Hg으로 차이를 보여 검사한 결과 빗장 밑 동맥 도류 증후군을 진단하고 비교적 간단하게 요골 동맥 (radial artery)을 통하여 경피적 혈관 성형술로 스텐트를 삽입 하여 좋은 결과를 얻어 문헌 고찰과 함께 보고하는 바이다.

지능형 OCR 시스템을 위한 한글 필기체 생성 및 분류 모델에 관한 연구

백진성,정상중,정도운,서지윤 한국융합신호처리학회 2022 융합신호처리학회 논문지 (JISPS) Vol.23 No.4

본 논문에서는 다양한 산업분야에 적용 가능한 딥러닝 알고리즘 기반의 한글 필기체 생성 및 분류 모델을 구현하였다. 구현된 GAN 기반의 한글 필기체 생성 모델과 CNN 기반의 한글 필기체 분류 모델 2가지로 구성되어 있다. GAN 모델은 가짜 한글 필기체 데이터를 생성하기 위한 생성자 모델과 가짜 필기체 데이터를 판별하기 위한 판별자 모델로 구성된다. CNN 모델의 경우 'PHD08' 데이터세트를 활용하여 모델의 학습을 수행하였으며, 학습 결과 92.45% 정확도로 한글 필기체를 분류하는 것을 확인하였다. 구현된 GAN 모델을 통해 생성된 한글 필기체 데이터를 기존 CNN 모델의 학습 데이터세트와 통합하여 분류 모델의 성능평가를 진행한 결과 96.86%로 기존 분류 성능보다 우수하게 나타남을 확인하였다.

금강 유역의 홍수상황 및 조치

정상만,백기우 한국수자원학회 1995 한국수자원학회논문집 Vol.28 No.5

六味地黃湯加味方이 뇌혈류역학에 미치는 기전연구

백영찬(Young Chan Back),김정상(Jeong Sang Kim),김영희(Young Hee Kim),정현우(Hyun Woo Jeong) 한의병리학회 2001 동의생리병리학회지 Vol.15 No.5

운동유형에 따른 요추 수술환자의 요부 신전근력과 통증정도의 변화

정상선,김지영,엄현섭,백영수,김한수 한국운동재활학회 2011 JER Vol.7 No.3

The purpose of this study was to investigate the effect of the muscular exercise and balance exercise on lumbar muscular strength in patients with lumbar spine surgery. Three groups were performed 60 minutes per day and three times a week during 8 weeks. At pre and post exercise, Medx lumbas extension strength test and VAS scale were conducted. The lumbar extension strength was measured at seven degrees of lumbar flexion angles, which are 0°, 12°, 24°, 36°, 48°, 60° and 72° before and after the exercise program. Visual analogue scale was measured by modified table of visual table of analogue scale. The data were analyzed utilizing two-way ANOVA with repeated measures. The results were as follows: 1. As a result of measuring lumbar muscular strength before and after carrying out the exercise program, lumbar muscular strength of the balance exercise group has increased significantly (p<.001, p<.01, p0.05) compared to the muscular exercise group. 2. As a result of measuring visual analogue scale before and after carrying out the exercise program, visual analogue scale of the balance exercise group has decreased significantly (p<.05) compared to the muscular exercise group. Especially, it was shown that balance exercise training was more effective in enhancing the variables compared to resistance exercise training, indicating that the exercise training program for improving the lumbar muscular strength and the abdominal strength for patients with lumbar spine surgery..

Paroxysmal Atrial Fibrillation Presenting as Acute Lower Limb Ischemia

백우열,오미경,기지훈,김하경,정상식 대한가정의학회 2011 Korean Journal of Family Medicine Vol.32 No.7

An ischemic foot can be developed by acute arterial occlusion. Given proper treatment within critical time, the patient can avoid foot amputation and death. Early proper diagnosis and treatment by family physician at the initial clinical interviewing is important in saving the affected leg and the life. Thrombosis and embolism are the common causes of acute arterial occlusion. Thrombosis mostly arises from underlying cardiac disease such as arrhythmia, coronary artery disease and valvular heart disease while arterial occlusion by embolism can be shown on a narrowed artery related with systemic atherosclerosis. Because the treatment options depend on the underlying cause of the acute ischemic foot, it is important to identify the cause of acute ischemic foot. At this paper, we reported a case that the cause of acute ischemic foot of the patient proved paroxysmal atrial fi brillation after some diagnostic tests.

금강 유역의 홍수상황 및 조치

정상만,백기우 한국수자원학회 1995 물과 미래(한국수자원학회지) Vol.28 No.5

다공성 여재를 이용한 고정생물막 반응기 특성에 관한 연구

백명석,정상철,이영신,김동민 대한환경공학회 1995 대한환경공학회 학술발표논문집 Vol.1995 No.12