To investigate the effect of hyperoxia on EKG findings and to evaluate the applicability of EKG as noninvasive monitoring index of oxygen toxicity, 38 rabbits were continuously exposed to 6 different conditions-3 hyperbaric oxygenations (HBO-2.5, 3.5 and 5ATA, 100% O2), normobaric oxygenation (NBO, 100% O2), hyperbaric aeration (HBA-5ATA, 21% O2) and normobaric aeration (NBA, 21% O2)-for 120 minutes and their EKG and time to dyspnea and convulsion were recorded. Dyspnea and death were observed in exposure conditions of HBO-3.5 and HBO-5 (Positive rate of dyspnea; 10%, 100%, death; 10%, 25%, respectively) only, and convulsion in 4 oxygenation groups (NBO; 20%, HBO-2.5; 20%, HBO-3.5; 20%, HBO-5; 88%). Abnormal EKG findings included arrhythmia and ST-T changes and the incidences was increasing with doses(partial pressure of oxygen). In addition to EKG change, findings observed during exosure were dyspnea and convulsion in the order of appearence and when non specific ST-T change was accepted as positive (abnormal) finding, the frequency of abnormal EKG was statistically significant(p<0.01), but when it was excluded from positive results, the frequency of EKG change was not significant(p>0.05). These results suggest that the effect of hyperoxia on heart is myocardial ischemia and arrhythmia, that oxygenation more than 3.5ATA causes myocardial damage in 120 minutes exposure, and that EKG is valuable as monitoring index of oxygen toxicity.
Arrhythmias, Cardiac ; Dyspnea ; Electrocardiography* ; Heart ; Hyperbaric Oxygenation ; Hyperoxia* ; Incidence ; Myocardial Ischemia ; Oxygen ; Rabbits* ; Seizures

No abstract available.
Stomach Neoplasms*

Chronic complication of diving and working in compressed air is dysbaric osteonecrosis. Dysbaric osteonecrosis could be diagnosed by simple bone x-ray, in the case of exposure history to dysbaric atmosphere. The case is 44 years old man who worked as a shell fish diver for 20 years. He was exposed dysbaric atmosphere during diving. He had bone necrosis in both femur head, both distal femur and proximal tibia. He had multiple attacks of decompression sickness. Other causes of bone necrosis are ruled out. We conclude that diver's bone necrosis is dysbaric osteonecrosis.
Adult ; Atmosphere ; Compressed Air ; Decompression Sickness ; Diving ; Femur ; Femur Head ; Humans ; Necrosis ; Osteonecrosis* ; Tibia

No abstract available.
Bone Plates ; Mandible ; Odontoma ; Transplants

OBJECTIVES: This study was performed to investigate the effectiveness of the questionnaire. METHODS: Workers'health examination records, work environment record, and questionnaires of selected industries as samples were analysed using logistic regression analysis and discrimination analysis Results'Cases of bearing impairment (Dl+C) as dependent variables, and age, work duration and level of environmental noise as independent variables were selected for multiple unconditional logistic regression analysis. Odds ratio was 4.04 in hearing difficulty, 2.78 in tlnnitus and 1.08 in age. In the second analysis Noise induced hearing loss is selected as dependent variable. The OR in hearing difficulty was 3.67(95 % C.1. : 1.61 8.61), and was 1.09(95 % C.1. : 1.05-1.14) in age. Conditionnal multlple logistic regression analysis was performed. In hearing impairment as dependent variable, the OR of age was 1.02(95 % C.1. : 1.00-1.04) and other variables were not significant. However, NIHL as dependent, the OR of hearing difficulty was 4.57(95 % C.1. : 1.43-14.67). According to multiple logistic regression adopting each items of questionnaire as dependent variable, the only item of hearing difficulty showed significant difference with hearing ability. The discrimination analysis was performed with the class variable of hearing impairment, and discrimination variables of age, work duration, and environment noise level. The sensitivity of 59 %, and specificity of 88 %, and average error count of 23 % were obtained. When the numbers of items answered in questionnaire were assumed as the parameter of judgement for noise induced hearing loss (NIHL), the highest sensitivity and specificity were 33.5% and 49.0% in cases of more than two items answered. CONCLUSIONS: The development of items that is simple and discriminative mainly consisted of chronic and specific diseases related items is needed. Computerization for newly developed items might be needed to establish effective surveillance system for NIHL in the future.
Discrimination (Psychology) ; Hearing Loss* ; Hearing* ; Logistic Models ; Mass Screening* ; Noise* ; Odds Ratio ; Questionnaires* ; Sensitivity and Specificity

Although some employees working for Seoul Metropolitan Subway Cooperation are working at the noisy workplaces, they has been excluded from Special Periodic Health Examination Program. And some workers complained of hearing loss or tinnitus. So, this study was carried out to investigate the prevalence rate of Noise Induced Hearing Loss of employees(10,792) working for Seoul Metropolitan Subway Cooperation. The number of subjects were total 10,792 with 10,355 men and 437 women. A questionnaire survey, otological examination, Rinne test, pure tone audiometric tests were performed and through the first and second screening audiometric examination, 605 workers were selected after excluding employees with past otologic problems, recent exposure to high level noise, and under medications. and the results were as follow; 1. Among 10,792 workers, 4 workers(0.037%) diagnosed as NIHL and 601 workers(5.56%) as early NIHL. As workers grew older, the prevalence rate of NIHL and early NIHL became more rising. 2. The prevalence rate of NIHL and early NIHL was different between work site. After age adjustment, The prevalence rate of NIHL and early NIHL was 23.74% in Train repairmen{80dB(A)}, 3.1% in Station staffs{below 70dB(A)}, 2.53% in Train crew{below 70dB(A)}, 2.1% in Office workers. 3. The perception rate of necessities of ear plug in NIHL and early NIHL was below 55% and wearing rate of ear plug in NIHL and early NIHL was 1.1% In conclusion, some employees who was under working environment in Seoul Metropolitan Subway Cooperation should be monitored to prevent hearing impairment and would be needed health education.
Ear ; Female ; Health Education ; Hearing Loss* ; Hearing* ; Humans ; Male ; Mass Screening ; Noise* ; Prevalence ; Railroads* ; Seoul* ; Tinnitus ; Workplace ; Surveys and Questionnaires

We observed the effect of application of n-PTFE on mandibular bone defects in the rabbit. GTR is based on the hypothesis that during wound healing, non-osteogenic cells are mechanically blocked from entering a bone defect. This allows the slower-migrating mesenchymal cells from the surrounding bone and marrow, having osteogenic potential, to move the defect site. Bilateral through & through defects, 8mmx4mm in size, involving the inferior border of mandible, were created in the mandible angle of 15 rats. The experimental side was applied with high-density n-PTFE membrane, with the opposite side serving as a control. In the first week of the early experimental period, the bone defects of experimental groups were filled with highly vascularized fibrous connective tissue showing prominent osteoblastic activity with osteoid formation, whereas the defects of control were replaced by dense fibro-muscular tissue without osteoblastlf activity. After 3 weeks, the experimental group revealed well formed bone trabeculae and fibro-vascular marrow within surrounding membrane. With time the amount of new bone was decreased with increase of hematopoietic marrow, and the cortical plate composed of dense mature bone was more thicker. In the whole experimental periods, the inflammation and foreign body reaction were not found around the inserted n-PTFE membrane. After removal of membrane there was marked remodeling of newly formed bone by active osteoclasts in periosteal soft tissue, which decreased the bone volume apparently. These findings suggest that n-PTFE has biocompatibility, flexibility, and rigidity and offer rapid bone regeneration within limited area by the membrane. On the other hand, the early removal of membrane caused reduction of bone volume by the osteoclastic resorption. Thus, the time of removal may be more important factor for maintenance of regenerated bone volume.
Animals ; Bone Marrow ; Bone Regeneration ; Connective Tissue ; Foreign-Body Reaction ; Hand ; Inflammation ; Mandible ; Membranes ; Osteoblasts ; Osteoclasts ; Pliability ; Rabbits* ; Rats ; Wound Healing

BACKGROUND: The propose of this study was to identify the level of medical technologists' perception of and compliance with hospital infection control guidelines. METHODS: A questionnaire survey was conducted for 65 medical technologists working at three university hospitals in Seoul and Kyunggi areas. The questionnaire was composed of 34 questions on the general characteristics (14 items) of individual responders and about infection control guidelines (20 items). Their response was marked on the basis of 5 points for each question. RESULTS: The mean scores of the perception of and compliance with the infection control guidelines were 4.62+/-0.34 and 3.85+/-0.42, respectively. The female technologists scored significantly higher than did the male counterparts in the participation level of the infection control guidelines (P<0.05). The medical technologists who had participated in an infection control educational program were more likely than those who had not to show a higher compliance level on the infection control guidelines (P<0.05). CONCLUSION: The study demonstrated that the development of infection control educational programs for medical technologists and a supportive policy of the hospital administration should contribute to the prevention of nosocomial infections.
Compliance* ; Cross Infection* ; Female ; Gyeonggi-do ; Hospital Administration ; Hospitals, University ; Humans ; Infection Control ; Male ; Medical Laboratory Personnel ; Seoul ; Surveys and Questionnaires

In vivo ethane production in rats was used as an index of oxygen toxicity. The rats were allocated to four exposure conditions; hyperbaric oxygenation (HBO=5 ATA, 100% O2), normobaric oxygenation (NBO=1 ATA, 100% O2), hyperbaric aeration (HBA=5 ATA, 21% O2) and normobaric aeration (NBA=1 ATA, 21% O2). After 120 minutes of exposure, the rats exposed to high concentration and/or high pressure oxygen exhaled significantly larger amounts of ethane than those exposed to NBA, and the differences in ethane production between any two groups were statistically significant (p<0.01). This finding supports the hypothesis that hypothesis that hyperoxia increase oxygen free-radicals and the radicals produce ethane as a result of lipid peroxidation. It is notable that the ethane exhalation level of the HBA group was significantly higher than that of the NBO group. This difference could not be accounted for by the alveolar oxygen partial pressure difference between the two groups.
Animals ; Ethane* ; Exhalation* ; Hyperbaric Oxygenation ; Hyperoxia* ; Lipid Peroxidation* ; Oxygen ; Partial Pressure ; Rats

No abstract available.