모 축전지 회사 근로자들의 연폭로 지표에 대한 경시적 관찰

강명식,김용배,이용진,리갑수,김화성,황규윤,장봉기,이성수,안규동,이병국 순천향대학교 산업의학연구소 1998 순천향산업의학 Vol.4 No.1

Lead poisoning is still prevalent and one of important occupational disease in Korea. To prevent undue high lead burden and maintain good health condition of lead workers in lead using industries, periodic health examination and regular biological monitoring of lead workers are often required in addition to the fundamental improvement of their working condition. To evaluate the effect of comprehensive occupational health program with regular biological monitoring on the level of lead exposure of lead workers in lead using industries, 11 year database from 1983 to 1994 of one storage battery factory was reviewed. From 1983 to end of 1986 only periodic health examination was provided to the lead workers, but from 1987 comprehensive occupational health program with regular biological monitoring was provided to maintain better health condition of lead workers. Selected study variables for lead exposure were blood lead(PbB), zinc protoporphyrin in blood(ZPP), δ-aminolevulinic acid in urine(ALAU), hemoglobin(Hb), hematocrit(HCT). Information on sex, age and work duration was also reviewed. 5 years data from 1983 to 1987 and 3 years data from 1990, 1993 and 1994 were available for all lead exposure indices except ALAU which has only 5 years data from 1983 to 1997. The results of 11 years longitudinal observation of lead indices are all follows: 1. The mean value of ZPP of lead workers in 1983 was 148.7±73.1 ㎍/㎗(Male: 145.5±72.3, Female: 168.1±79.1), whereas that of ZPP of lead workers in 1994 was decreased to 64.3±32.7 ㎍/㎗(Male: 60.2±28.8, Female: 95.2±43.4). 2. The mean value of PbB of lead workers in 1983 was 56.4±18.8 ㎍/㎗(Male: 55.59±19.1, Female: 59.6±19.1), whereas that of PbB of lead workers in 1994 was dcreased to 35.4±11.9 ㎍/㎗(Male: 35.7±12.0, Female: 32.8±10.8). 3. The mean value of Hb of lead workers in 1983 was 14.1±1.4 g/㎗(Male: 14.4±1.1, Female: 11.7±0.8), whereas that of Hb of lead workers in 1994 was increased to 15.6±1.5 g/㎗(Male: 15.9±1.2, Female: 12.9±1.1). 4. Blood lead is most highly correlated with ZPP(r=0.522, male:0.54 and female:0.50) and also correlated with ALAU and work duration also. 5. The simple regression analysis of PbB and ZPP showed different coefficient of regression by the measurement year, but there was no difference of coefficient of regression between sex. The slope of equation of pooled data for 1983-1986 without comprehensive occupational health program was 2.16 and differed from that of pooled data for 1987-1994(1.25). This difference suggests that the unit effect of blood lead on ZPP was relatively smaller in later period of comprehensive occupational health program than carly period without comprehensive program. The slope change in the analysis of linear regression of PbB on ZPP in lead workers can be used to evaluate the possible effect of health intervention to prevent undue high lead absorption in lead using industries. 6. 11 years occupational health service in this storage battery factory brought out considerable improvement of health status of lead workers in terms of decrease of PbB and ZPP and increase of Hb and the improvement was more remarkable after the introduction of comprehensive occupational health program.

말기신부전 환자에서 혈액투석 전후의 QT간격분산 비교

강대웅,정지용,윤나라,안치용,김종오,신병철,정종훈,김현리 朝鮮大學校 附設 醫學硏究所 2006 The Medical Journal of Chosun University Vol.31 No.2

Background: Some cases of QT interval, corrected QT interval (QTc), QT dispersion (QTd) and corrected QT dispersion (QTcd) have been reported in ESRD, but these results are variable and the influence of a hemodialysis is still controversial, In this study, we investigated the effect of hemodialysis on QT and QTc interval and QT and QTc dispersion in patients with ESRD 15 min before and 15 minute after each hemodialysis. Methods: Sixty-seven patients with ESRD (men 33 & women 34) on three-times stable hemodialysis (>3 months) were randomly enrolled. Fifty control subjects with a similar age and normal renal function were enrolled from this hospital. Routine biochemical studies were measured pre- and post dialysis, at the time of the ECG. Plasma Na+, K+, BUN, creatinine, ionized calcium and phosphate were checked. Twelve-lead electrocardiographs were performed at 10㎜/mv and 50㎜/s using a HewIett-Packard Pagewriter 100, before and after a single hemodialysis session.The QT interval was measured from the onset of the QRS complex to the end of the T wave. If the end of the T wave was not clear in a particular lead then it was excluded from analysis. When U waves were present, the end of the T wave was taken as the nadir between the T and U waves. Each QT interval was corrected for heart rate using Bazett's formula (QTc==QT/√(RR)) (ms). The difference between maximal and minimal QT interval duration was defined as QT dispersion (QTd) in each of the 12 leads. Result: This study demonstrates that QT, QTd, QTcd is higher in hemodialysis patients compared with control subjects, and QT and QTd rise postdialysis to levels comparable to those seen acutely following myocardial infarction, when patients are at greatly increased risk of potentially fatal ventricular arrhythmias, Conclusions: QT interval and QT dispersion, markers of risk for arrhythmias and sudden death, are elevated in hemodialysis patients, and rise postdialysis. QT interval and QT dispersion is an easily obtainable, noninvasive, simple, inexpensive, and widely available method of risk stratification in uremic patients receiving chronic dialysis. Additional studies are needed to clarity whether increased postdialysis QT dispersion results in an increased occurrence of arrhythmias.

CFD를 이용한 광촉매 정수장치모듈의 최적구조 국문제목

강한용,최병철,김종호 한국공업화학회 2004 응용화학 Vol.8 No.1

The flow fields inside the photo-catalytic module for water treatment system were studied. The fluid flow inside the module was visualized mainly by CFD (computer fluid dynamics) analysis, and the numerical analysis was authorized by PIV(particle image velocimetry) measurement. The flow patterns in the module for 3 types of innards and 6 kinds of flow rate were analyzed by CFD. Model 1 had better performance below 0.1 L/s of the flow rate, and model 2 over 0.2 L/s of the flow rate with the homogeneous flow field innards of photo-catalytic module.

악성 갑상선 우연종의 임상상 및 초음파 소견의 진단적 가치

강한욱,김광원,이병완,강보현,김형훈,김범진,정재훈,민용기,이명식,이문규 대한내분비학회 2002 Endocrinology and metabolism Vol.17 No.5

연구배경: 최근 갑상선 초음파 검사의 빈번한 시행으로 갑상선 우연종의 발견이 증가하고 있다. 이러한 갑상선 우연종은 임상적으로 어떻게 접근하고 치료를 해야 하는지 적지 않은 문제가 되고 있다. 본 연구에서는 직경 1.5㎝ 이하의 갑상선 우연종의 유병률, 입상적 특징 및 초음파 특성, 그리고 가장 효율적인 진단적 접근에 대해 알아 봤다. 방법: 1999년 1월부터 2000년 12월까지 삼성서울병원 내과 및 일반외과로 갑상선 결절을 주소로 내원한 1457명을 대상으로 후향적 연구를 시행하였다. 우연히 발견된 직경 1.5㎝ 이하의 갑상선 결절을 가지는 환자들에서 갑상선 결절의 촉지 유무, 갑상선 기능검사, 항갑상선 항체, 갑상선 초음파 및 미세침 흡인세포검사, 99m^Tc 갑상선 스켄, 수술 조직검사 및 병기를 검토하였다. 결과: 분석한 갑상선 결절 1475예 중 갑상선 우연종의 유병률은 13.4%(198예)였다. 갑상선 우연종에서 악성률은 28.8%(57예)으로 나왔다. 양성 및 악성 갑상선 우연종에서 나이, 성별, 갑상선 기능검사, 결절 크기에는 의미 있는 차이는 없었다. 갑상선 스켄은 갑상선 우연종의 감별에 적합하지 않았다. 갑상선 결절의 초음파 지표 점수만이 양성 및 악석 갑상선 우연종의 감별에서 초음파 지표 점수의 민감도는 88.9%, 특이도는 74.4%, 양성 예측률은 92.4%로 나왔고 진단적 정환도는 85.5%였다. 갑상선암으로 수술을 받은 50명중 stage 1은 34명, stage 2는 6명, stage 3은 10명으로 대부분의 악성 갑상선 우연종은 낮은 TNM 병기로 나타났으나, 상당수에서는 국소 침범의 소견을 보였다. TNM 병기의 3기 환자 전부는 45세 이상이였고, 주로 갑상선암의 피막 침범에 의한 것이었다. 임파절 전이는 6명의 환자에서 나왔다. 결론: 악성 갑상선 우연종은 비교적 흔히 접할 수 있는 질환이며 양성 우연종과는 임상적으로 구별이 안 된다. 악성 갑상선 우연종은 발견 당시 대부분 낮은 병기이나, 갑상선의 피막 침범 및 임파절 전이가 상당수에서 발견되었다. 갑상선 우연종의 초음파 소견은 향후의 진단 방향을 제시하는 중요한 길잡이가 될 수 있다. 초음파 지표 점수 2점 이상의 갑상선 우연종에서만 초음파 유도 미세침 흡입검사를 권장한다. Background: High-resolution ultrasonography has made the detection of asymptomatic small thyroid possible. Recent increases in the detection of incidentalomas have created a clinical dilemma on how to properly manage such incidental nodules. We investigated the prevalence, clinical and ultrasonographic characteristics, and optimal diagnostic approach toward incidentally detected benign and malignant thyroid nodules of less than 1.5㎝ in size. Methods: A retrospective review was undertaken on the 1,475 patients who had visited Samsung Medical Center, Seoul Korea between January 1999 and December 2000. The review consisted of a physical examination of the thyroid gland, thyroid function test, antithyroid antibodies, thyroid ultrasonography, fine-needle aspiration biopsy, pathology and TNA staging of the incidentally detected thyroid nodules of less than 1.5㎝ in size. Results: The prevalence of thyroid incidentalomas was 13.4% and the malignancy rate within them was 28.8%. There were no significant differences in age, sex, thyroid function test and size between the benign and malignant incidentalomas. Ultrasonographic characteristics showed meaningful diagnostic value for the detection of malignancy in incidentalomas. Most malignant incidentalomas were of a low stage. Conclusion: Occult thyroid cancers are fairly common finding. There are no clinical difference between benign and malignant thyroid nodules less than 1.5㎝; however, ultrasonographic findings can be used to decision of optimal management strategies (J Kor Soc Endocrinol 17:649∼656, 2002).

Rat의 복강내에 투여한 5-fluorouracil-polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

강대영,송규상,최정목,노승무,정경수,오정연,김진향,양준묵,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

For more effective intraperitoneal chemotherapy, the authers made 5-fluorouracil-polyglycolic acid composite disks(FU-PGA disks) with 5-fluorouracil and polyglycolic acid, a biodegradable polymer. We inserted the FU-PGA disk into the peritoneal cavites of Sprague-Dawley male rats, the control and three experimental groups; one FU-PGA disk insert group(300mg/kg), two FU-PGA disk insert group(600mg/kg), and three FU-PGA disk insert group(900mg/kg). The control group received a similar number of PGA disk inserts. A pharmacokinetic study was performed to measure the 5-fluorouracil concentration in the peritoneal fluid, blood, and tissues(liver, kidney and heart) at 24 hours, 72hours and 168 hours after insertion of the FU-PGA disk. Light and electron microscopic studies were done. The results were as follows: 1) The number of white blood cells and platelets decreased after FU-PGA insertion. The degree was proportional to the duration and amounts inserted. The change in the number of red blood cells varied slightly. 2) Light microscopically, slight changes were noted at 168 hours in the 3 disk insert group (900mg/kg). Mild fatty change and hepatocyte degeneration around the central veins of the liver were noted, with vacuolar degeneration in the proximal convoluted tubules of the kidney. 3) Electron microscopically,the liver showed focal increases of lipid droplets in the hepatocytes, and irregular nuclear membrane with focal nucleolar segregation of the fibrillar and granular elements. Also the double membranous structure of the hepatocytes and Kupffer cells was widened with bleb formation. The kidney showed wide separation of the nuclear double membrane in the proximal convoluted tubular cells and mesangial cells, with vacuolation and myelin figure formation in the mitochondria of the proximal convoluted tubular cells, at 72 hours and 168 hours in the 2 to 3 FU-PGA insert groups. The heart showed focal loss of cristae,vacuolation and myelin figure formation in the mitochondria of the 2 to 3 FU-PGA insert groups. In conclusion, despite the large amont of FU-PGA inserted, the histopathological changes in the liver, kidney and heart were slight, and consonant with the very low amount of 5-fluorouracil concentrations detected in the liver, kidney and heart. The above results suggest that the FU-PGA composite can serve as a new device for releasing drugs in a controlled manner and easily targeted to intraperitoneal organs. This device can improve the efficacy of intraperitoneal chemotherapy for gastric cancer.

내시경적 점막절제술로 치험한 식도 과립상 세포종 1례

강혁주,김성욱,최석진,이중현,장재식,서영범,윤병구,박건욱,김성자,김용섭,강승완,이구,양창헌,이창우,김욱년,이광헌,서정일 동국대학교 의학연구소 2000 東國醫學 Vol.7 No.-

과립상 세포종은 Schwann 세포 기원으로 생각되며 인체에 비교적 드물게 발생한다. 과립상 세포종은 전신 어느 곳에서나 발견될 수 있으나 주로 혀, 구강, 피부 혹은 유방 등에서 호발하며 드물게 위장관에서 발견된다. 위장관에서는 식도에서 가장 호발하며 다음으로 위, 대장 순이다. 과립상 세포종은 대부분, 특히 위장관에서는 양성이며 소수의 악성 병변이 보고되었다. 이러한 이유와 함께 수술 전의 진단이 어렵기 때문에 과립상 세포종에 대한 근본적인 치료는 현재까지 외과적 절제술이다. 최근에 시도되는 치료방법들로는 내시경적 레이저 치료, 용종절제술, 내시경적 점막 절제술 등이 있다. 저자들은 상부 소화관 내시경검사를 시행하여 식도 과립상 세포종을 진단하고 내시경적 점막 절제술을 시행하여 합병증 없이 퇴원하여 현재 재발없이 경과 관찰중인 1례를 경험하였기에 보고하는 바이다. Granular cell tumors, which occur infrequently, are probably of Schwann cell origin. They can occur almost anywhere in the body but usually affect the tongue, oral cavity, skin, or breasts and are rarely found in the gastrointestinal tracts. The esophagus is the most frequent gastrointestinal site, followed by the stomach and the colon. Granular cell tumors are generally benign, especially in the gastrointestinal tract, some malignant lesions have been reported. For this reason, and also because preoperative diagnosis is difficult, the standard treatment for granular cell tumor has until now been surgical excision. In recent years, other therapeutic methods is endoscopic laser therapy (ELT), polypectiomy, endoscopic mucosal resection (EMR). We report a case of esophageal granular cell tumor which was diagnosed by an endoscopy and managed using an endoscopic mucosal resection without complication.

아세클로페낙 연질캡슬(클란자 에스 연질캡슬)의 개발

용철순,이경희,최진석,박병주,정세현,김용일,박상만,배명수,김귀자,김영식,유창훈,강성룡,유봉규,이종달,최한곤 한국약제학회 2004 Journal of Pharmaceutical Investigation Vol.34 No.1

To develop and aceclofenac soft capsule, four preparations with various solubilizers were prepared and their dissolution test was carried out. Among four preparations tested, a preparation with ethanolamine was selected a formula of aceclofenac soft capsule (Clanza S^(™), since it showed the fastest dissolution rate. Bioequivalence of aceclofenac tablet, Airtal^(™)(Dae-Woong Pharmaceutical Co., Ltd.) and aceclofenac soft capsule, Clanza S^(™)(Korea United Pharmaceutical Co., Ltd.) was evaluated according to the guideline of KFDA. Fourteen normal male volunteers (age 20-25 years old) were divided into two groups and a randomized 2×2 cross-over study was employed. After oral administration of one tablet or capsule containing 100 ㎎ of aceclofenac, blood ws taken at predetermined time intervals and the concentration of aceclofenac in plasma wa determined with an HPLC method under UV detector. The pharmacokinetic parameters (C_(max), T_(max) and AUC_(t)) were calculated and ANOVA was utilized for the statistical analysis of parameters using logarithmically transformed AUC_(t), C_(max) and T_(max) between Airtal tablet and Clanza soft capsule were 2.89%, 0.18% and 43.0%, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log(0.8) to log(1.250(e.g.log(0.81) - log(1.23) and log(0.89) - log(1.14)) for AUC_(t) and C_(max), respectively. Thus, the criteria of the KDFA guidelines for the equivalence was satisfied, indicating that Clanza S^(™) soft capsule is bioequivalent to Airtal^(™) tablet.

표면근전도와 전자각도기를 이용한 자동차 부품 조립작업 위험요인 평가

강동묵,이철호,,신용철,김은아,우지훈,조병만,이수일 大韓産業醫學會 2005 대한직업환경의학회지 Vol.17 No.4

Objectives: As automobile part manufacturing is characterized by high speed and high repetition, observation methods which are usually utilized for static posture are inappropriate to evaluate musculoskeleatal risk factors. This study quantified the risk factors of musculoskeletal disorders on the forearm and suggested exposure limits by estimating the risk factors using surface electromyography (EMG) and electrogoniometer. Methods: Ten percent of the total workers at 3 automobile part manufacturing factories were randomly selected, and 99 male workers were recruited as study subjects. The study was conducted during May 2003 to September 2004. The workers were equipped with electrogoniometers on the wrist and the elbow, surface EMGs on the skin of the flexor digitorum superficialis (FDS) and extensor carpi radialis (ECR) muscles, and the heart beat recorder during work as indicators of joint movement, local muscle tension and physical work load, respectively. Results: After controlling for age, body mass index and job stress, wrist flexion maximum angle, FDS relative activity (RA) and ECR RA were significantly associated with forearm musculoskeletal symptoms. The odds ratios of the forearm were 5.0(95% CI: 1.1-22.7), 14.0(95% CI: 1.5-128.8) and 7.3(95% CI: 1.1-49.4) for wrist flexion maximum angle more than 76˚, FDS RA more than 2.8%, and ECR RA more than 3.5%, respectively. Conclusions: Joint angle and focal muscle activity were associated with forearm musculoskeletal symptoms. To reduce forearm musculoskeletal symptoms among automobile part manufacturers, the wrist flexion angle, and FDS and ECR activity need to be reduced below the guidelines recommended in this study.

오스테나이트계 TP347 스테인레스강의 파괴저항특성 평가

강병구,김수용,석창성 成均館大學校 科學技術硏究所 1999 論文集 Vol.50 No.1

The objective of this paper is to evaluate the material properties of TP347 stainless steel and their associated welds and the welded joint of the carbon steel and the stainless steel manufactured for primary coolant system of Ulchin 3 & 4 nuclear power plants. The effect of various parameters such as pipe size, welding method, chemical composition, crack plane orientation, metallography and fractography on the material properties were discussed. Test results showed that the effect of pipe size on fracture toughness was negligible while the effect of welding method on fracture toughness was significant. In addition, the drop of fracture toughness in the field fabrication weld of TP347 stainless steel is probably due to the large amount of σ-phase precipitated on the δ-ferrite boundary and the large size dimple.

정밀전단시의 유한요소 해석을 위한 파단기준 연구

강대철,전병희,이원평,성부용 韓國工作機械學會 2000 한국생산제조학회지 Vol.9 No.5

The Tailor Welded Blanks(TWB) are using various materials (different thickness, strength and different materials) can be welded together prior to the forming process. Therefore, TWB applications have become little by little important in automobile industries, because it has more light weight and process reduction. A burnish area is very important for TWB using laser welding. In this paper, evaluated failure criterion, effect of clearance and distance of between pad and punch by computer simulation. We used element separation method for fracture. And applied a plastic strain to failure criterion. According to the analysis results, we obtain failure criterion, when plastic strain is 2.0. The burnish area and clearance were inverse proportional.