1.The effects of heat treatment on mechanical properties and metal release from heat-treated orthodontic archwires.
Chul Min CHOI ; Byung Tae RHEE
Korean Journal of Orthodontics 1990;20(2):381-390
The purpose of this study was to evaluate the effects of heat treatment on mechanical properties in 0.016" x 0.022" blue Elgiloy wires and to measure the amounts of nickel and chromium released from the wires in artificial saliva. Ultimate tensile strength, yield strength and elongation were measured with universal testing machine (Instron). and the amounts of nickel and chromium released from the sample were measured with atomic absorption spectrophotometer after one week immersion in the artificial saliva. Ultimate tensile strength and yield strength were progressively increased below 1000degreesF, but elongation was decreased. And the results were reversed above 1100degreesF. After heat treatment of the sample for 9 minutes at 1000degreesF, the maximum tensile strength and yield strength were 213.6kg/mm2, 140.1kg/mm2, respectively. Both tensile strength and yield strength were decreased progressively above 1100degreesF. Elongation was appeared the minimum value (8.6%) after heat treatment for 9 minutes and 12 minutes at 1000degreesF. There was a pronounced increase in nickel and chromium liberation with increasing time and temperature. The maximum amounts of nickel and chromium released form the sample were 4.947microgram/cm2, 3.088microgram/cm2, respectively after heat treatment for 12 minutes at 1300degreesF. Heat treatment is applied to orthodontic wires, especially cobalt-chromium alloys, for the purpose of stress-relievning and hardening. When the heat-treatment of orthodontic wires, the heating procedure should be well controlled in order to have no effect on corrosion resistance and mechanical properties.
Absorption
;
Chromium
;
Chromium Alloys
;
Corrosion
;
Heating
;
Hot Temperature*
;
Immersion
;
Nickel
;
Orthodontic Wires
;
Saliva, Artificial
;
Tensile Strength
2.Postoperative results of endoscopic sinus surgery in patients with chronic paranasal sinusitis.
Yang Gi MIN ; Chae Seo RHEE ; Tae Yong KOH ; Kang Soo LEE
Korean Journal of Otolaryngology - Head and Neck Surgery 1993;36(3):450-458
No abstract available.
Humans
;
Sinusitis*
3.A Case of Spontaneous Cervical Spinal Epidural Hematoma: Case Report.
Jae Min PAIK ; Hoon CHUNG ; Gi Hwan CHOI ; Hyung Tae YEO ; Jung Kil RHEE
Journal of Korean Neurosurgical Society 1991;20(6):480-486
Spontaneous spinal epidural hematoma is a rare cause of spinal cord compression. Recently, at our hospital, the author et al had the opportunity of observing case with spontaneous cervical epidural hematoma in a 28 years old woman who had suddenly felt a strong pain in interscapular area. Rapidly after she noticed weakness in her legs and one day later she was completely paraplegia. The MRI of spine was done. There show tubular like low signal intensity at posterior epidural space of C7 level and ghigh signal intensity of cord at C7 level due to cord compression effect. In this article, we are adding one more rare case of spontaneous cervical spinal epidural hematoma confirmed by MRI.
Adult
;
Epidural Space
;
Female
;
Hematoma
;
Hematoma, Epidural, Spinal*
;
Humans
;
Laminectomy
;
Leg
;
Magnetic Resonance Imaging
;
Paraplegia
;
Spinal Cord Compression
;
Spine
4.A Study on Somatosensory Evoked Potential in Patients with Cervical Spondylosis.
Sung Min KIM ; Young Jin KIM ; Tae Sung KIM ; Bong Arm RHEE ; Gook Ki KIM ; Won LEEM
Journal of Korean Neurosurgical Society 1990;19(8-9):1145-1156
In order to study the relationship between clinical group of cervical spondylosis and electrical activity, we traced somatosensory evoked potential(SSEP) by stimulating the median nerve(MN) from the upper extremities, and the posterior tibial nerve(PTN) from the lower extremities simultaneously. The purpose of this study was to test the clinical diagnostic utility of the method, whether any consistent relationship exists between the severity and type of neurological symptoms and the results of the SSEP responses, and between neurological improved patients after operation and improved SSEP results. In this study patients were clinically divided into three groups : combined myelopathy and radiculopathy, myelopathy alone, radiculopathy alone. Over a 3-year period from 1987 to 1989, SSEP were performed on 112 patients of Korean adults and summary of the results obtained are as follows : 1) Among patients with cervical spondylosis, those with cervical myelopathy showed more abnormal SSEP than those cervical radiculopathy. 2) In the group with myelopathy, MN-cervical latensy, Ep-C2 interpeak latency. PTN-P1 latency, and N1 latency were prolonged more than MN-C2 latency, Ep-C2 interpeak latency, PTN-P1 latency, and N1 latency of the group with radiculopathy. 3) The longer the duration of the symptoms, the more abnormal were the SSEP in patients with cervical spondylosis. 4) In patient with cervical myelopathy, the latency of SSEP was prolonged not only in those with sensory deficit, but also with motor deficit. 5) Half of clinically improved patients after operation showed improved SSEP in follow-up examinations. 6) Improvement in SSEP after operation was much affected by posterior approach.
Adult
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Evoked Potentials, Somatosensory*
;
Follow-Up Studies
;
Humans
;
Lower Extremity
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Radiculopathy
;
Spinal Cord Diseases
;
Spondylosis*
;
Upper Extremity
5.Clinical analysis of cleft palate patients.
Yang Gi MIN ; Sun O CHANG ; Ha Won JUNG ; Ic Tae KIM ; Chae Seo RHEE ; Hong Ryul JIN
Korean Journal of Otolaryngology - Head and Neck Surgery 1992;35(2):321-327
No abstract available.
Cleft Palate*
;
Humans
6.Efficacy and Safety of Endoscopic Submucosal Dissection for Early Gastric Cancer in Patients with Comorbid Diseases.
Beom Jin KIM ; Tae Hoon CHANG ; Jae J KIM ; Byung Hoon MIN ; Jun Haeng LEE ; Hee Jung SON ; Poong Lyul RHEE ; Jong Chul RHEE ; Kyung Mee KIM ; Chul Keun PARK
Gut and Liver 2010;4(2):186-191
BACKGROUND/AIMS: Endoscopic submucosal dissection (ESD), a new and potentially curative method for treating gastrointestinal neoplasms, may have longer procedure time and the risk of complications when compared to conventional endoscopic mucosal resection. This study evaluated the efficacy and safety of ESD in patients with comorbid diseases. METHODS: The outcomes of 337 patients who underwent ESD for early gastric cancer at Samsung Medical Center from April 2003 to December 2006 were analyzed retrospectively. The Charlson comorbidity scale was used to divide the patients into low-risk (no risk factor) and high-risk (at least one risk factor) groups. The outcomes and complications were compared between the high- and low-risk groups. RESULTS: The low- and high-risk groups comprised 240 and 97 patients with mean ages of 61.1 and 64.7 years, respectively (p=0.002). Tumor location, tumor size, depth of invasion, procedure duration, and rates of en bloc resection, complete resection, complication, and recurrence did not differ significantly between the two groups (p>0.05). CONCLUSIONS: ESD may be a safe and effective treatment for early gastric cancer in patients with comorbid diseases.
Comorbidity
;
Gastrointestinal Neoplasms
;
Humans
;
Recurrence
;
Retrospective Studies
;
Stomach Neoplasms
7.Loss of Heterozygosity in Endometriosis.
Min A LEE ; Yun Ee RHEE ; Heung Tae NOH ; Sun Hoe KOO ; Ji Un KANG
Korean Journal of Obstetrics and Gynecology 2003;46(9):1724-1730
OBJECTIVE: Endometriosis is a very common gynecological condition in which tissue similar to endometrium proliferates at sites outside the uterine cavity. Although it generally remain a benign condition, malignant transformation has been documented, and it is commonly found in association with endometrioid subtype ovarian carcinoma. In order to identify the genomic change in those areas possibly involved in the pathogenesis of endometriosis, we performed LOH analysis. METHODS: Twenty seven cases of endometriosis were analyzed for the detection of LOH using 5 microsatellite markers. LOH analysis was performed by PCR, capillary electrophoresis and gene scan analysis using DNA from sections of tumor and normal tissue pairs. RESULTS: Twenty two of 27 (81.5%) cases demonstrated LOH at one or more loci. The frequency of LOH was 37.0% (D18S69), 25.9% (D22S274), 14.8% (D22S283), 7.4% (D6S286), 7.4% (D13S160). CONCLUSION: The frequencies of LOH was increased in higher stage of endometriosis. Most notable findings were found at chromosome 18 and 22 loci (D18S69, D22S274). These region might involve the some candidate genes closely related with the pathogenesis of endometriosis.
Chromosomes, Human, Pair 18
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DNA
;
Electrophoresis, Capillary
;
Endometriosis*
;
Endometrium
;
Female
;
Loss of Heterozygosity*
;
Microsatellite Repeats
;
Polymerase Chain Reaction
8.Fluoroscopic Guided Biopsy of Pulmonary Lesions: A Comparison of Fine Needle Aspiration with Large Needle Cutting Biopsy.
Heon LEE ; Young Min HAN ; Tae Gon JEONG ; Gyung Ho CHUNG ; Myung Hee SOHN ; Chong Soo KIM ; Ki Chul CHOI ; Dong Keun LEE ; Yang Keun RHEE
Journal of the Korean Radiological Society 1995;32(6):883-888
PURPOSE: To compare the diagnostic accuracy between fine needle and large cutting needle biopies. METHODS & MATERIALS: Chest lesion was biopsied consecutively by 19 G or 22 G fine needle and 14 G large cutting needle with interval of 10-20 min. 119 patients confirmed by operation or clinical follow-up were evaluated. RESULTS: There were 65 patient confirmed as malignant lesion and 54 confirmed as benign lesions. Diagnostic accuracy was 87.7%(57/65) for malignancy and 85.2%(46/54) for benign lesion with fine needle. With large cutting needle, it was 90.8%(59/65) for malignancy and 88.9%(48/54) for benign lesion. In the benign lesion, specific diagnostic accuray was 48.1%(26/54) with fine needle, and 64.8%(35/54) with large cutting needle biopsy, respectively. Complications were hemoptysis(n=13, 10.9%), pneumothorax(n=7, 5.9%) and mild to moderate chest pain. Although, it is impossible to compare the complications by the two types of biopsy on same lesion, 10 cases of immediate hemopytsis and more severe chest pain occurred when large cutting needle biopsy was done. CONCLUSION: No significant difference in diagnostic accuracy between fine needle and large cutting needle biopsies was observed in malignant lesion. In benign lesions, larger sample volume may increase the chance of obtaining a specific diagnosis but has no influence on overall diagnostic accuracy of benignity. Thus, we believe that fine needle aspiration biopsy is an accurate, safe, and more tolerable means to be performed as first step for diagnosis of chest lesions.
Biopsy*
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Biopsy, Fine-Needle*
;
Biopsy, Needle
;
Chest Pain
;
Diagnosis
;
Follow-Up Studies
;
Humans
;
Needles*
;
Thorax
9.The Medical Science Research and Development Supported by the Korea Science and Engineering Foundation.
Tae Sun MIN ; Jin HAN ; Seong Yong KIM ; Byoung Doo RHEE ; Myung Suk KIM
Journal of Korean Medical Science 2005;20(3):345-354
This study examined ways of promoting research in the medical sciences by evaluating trends in research funding, and the present status of research funding by the Korea Science and Engineering Foundation (KOSEF). This study analyzed statistics from KOSEF from 1978 to 2003 to examine support for research. In medical science field, group-based programs receive more funding than do individual-based programs. The proportion of research funds allocated to the medical sciences has increased markedly each year. Researchers in the medical sciences have submitted more articles to Science Citation Index (SCI) journals than to non-SCI journals, relative to other fields. Researchers supported by the Mission-Oriented Basic Grants program have published the majority of these papers, followed by those supported by the Programs for Leading Scientists, Regional Scientists, Leading Women Scientists, Young Scientists, and Promising Women Scientists, in that order. Funding by KOSEF reflects many decades of government support for research and development, the development and maintenance of necessary infrastructure, and the education and training of medical scientists.
Biomedical Research/*economics
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Foundations/*economics/statistics & numerical data
;
Humans
;
Korea
;
Research Support/*economics/trends
;
Research Support, Non-U.S. Gov't
;
Science
10.The Fifth Outbreak of Trichinosis in Korea.
Ji Young RHEE ; Sung Tae HONG ; Hye Jung LEE ; Min SEO ; Suk Bae KIM
The Korean Journal of Parasitology 2011;49(4):405-408
Trichinosis is a food-borne zoonotic disease caused by the nematode, Trichinella spp., and had been reported several times in Korea. Recently, there was an additional outbreak, involving 5 patients, the findings from which are reported herein. On 30 November 2010, 8 persons ate sashimi of the meat of a wild boar. Then, 2-3 weeks later, they complained of myalgia and fever. Unfortunately, muscle biopsy was not performed, but ELISA was performed using their sera. Two people among 8 were positive for Trichinella on the 34th day post-infection (PI), and 3 patients who initially revealed negative ELISA were additionally proved to be positive for trichinosis on the 42nd day PI. Hence, the confirmed patients of trichinosis were 5 in total in the present outbreak. They were treated with albendazole and discharged uneventfully. This was the fifth outbreak of trichinosis in Korea.
Adult
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Albendazole/therapeutic use
;
Animals
;
Anthelmintics/therapeutic use
;
Antibodies, Helminth/blood
;
Disease Outbreaks/*veterinary
;
Enzyme-Linked Immunosorbent Assay
;
Female
;
Foodborne Diseases/drug therapy/*epidemiology/parasitology
;
Humans
;
Male
;
Meat/*parasitology
;
Middle Aged
;
Republic of Korea/epidemiology
;
Sus scrofa/parasitology
;
Swine
;
Swine Diseases/parasitology/transmission
;
Treatment Outcome
;
Trichinella/immunology/*isolation & purification
;
Trichinellosis/diagnosis/drug therapy/*epidemiology
;
Zoonoses