• Radiation Oncology Journal
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• v.27 no.2
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• pp.91-102
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• 2009

Purpose: To compare the accuracy and efficacy of EDR2 film, a 2D ionization chamber array (MatriXX) and an amorphous silicon electronic portal imaging device (EPID) in the pre-treatment QA of IMRT. Materials and Methods: Fluence patterns, shaped as a wedge with 10 steps (segments) by a multi-leaf collimator (MLC), of reference and test IMRT fields were measured using EDR2 film, the MatriXX, and EPID. Test fields were designed to simulate leaf positioning errors. The absolute dose at a point in each step of the reference fields was measured in a water phantom with an ionization chamber and was compared to the dose obtained with the use of EDR2 film, the MatriXX and EPID. For qualitative analysis, all measured fluence patterns of both reference and test fields were compared with calculated dose maps from a radiation treatment planning system (Pinnacle, Philips, USA) using profiles and $\gamma$ evaluation with 3%/3 mm and 2%/2 mm criteria. By measurement of the time to perform QA, we compared the workload of EDR2 film, the MatriXX and EPID. Results: The percent absolute dose difference between the measured and ionization chamber dose was within 1% for the EPID, 2% for the MatriXX and 3% for EDR2 film. The percentage of pixels with $\gamma$%>1 for the 3%/3 mm and 2%/2 mm criteria was within 2% for use of both EDR2 film and the EPID. However, differences for the use of the MatriXX were seen with a maximum difference as great as 5.94% with the 2%/2 mm criteria. For the test fields, EDR2 film and EPID could detect leaf-positioning errors on the order of -3 mm and -2 mm, respectively. However it was difficult to differentiate leaf-positioning errors with the MatriXX due to its poor resolution. The approximate time to perform QA was 110 minutes for the use of EDR2 film, 80 minutes for the use of the MatriXX and approximately 55 minutes for the use of the EPID. Conclusion: This study has evaluated the accuracy and efficacy of EDR2 film, the MatriXX and EPID in the pre-treatment verification of IMRT. EDR2 film and the EPID showed better performance for accuracy, while the use of the MatriXX significantly reduced measurement and analysis times. We propose practical and useful methods to establish an effective QA system in a clinical environment.

• Clinical and Experimental Pediatrics
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• v.48 no.1
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• pp.40-47
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• 2005

Purpose : S. pneumoniae is one of major pathogens of community-acquired respiratory infections. The rate of antibiotic resistance to this organism has increased, and resistance to multiple antimicrobial agents in a single strain of S. pneumoniae may compromise the efficacy of empiric antimicrobial treatment commonly used for respiratory infections. We did this study to find out the penicillin resistant distributions and oral antibiotics susceptibility patterns against S. pneumoniae, isolated from pediatric patients with community-acquired respiratory infections in Korea. Methods : One hundred fifty six pneumococcal isolates obtained from pediatric patients with community-acquired respiratory infections such as acute otitis media(AOM), sinusitis and pneumonia between May 2000 to June 2003. And MICs of penicillin and oral antibiotics(amoxicillin, amoxicillin-clavulanate, cefaclor) were performed by broth microdilution methods according to the NCCLS(2003a). Results : Seventy eight percent of the isolates were resistant to penicillin. The isolates, collected from AOM patients showed the highest penicillin resistance(92.7%). The resistant rates of amoxicillin (16.7%) and amoxicillin-clavulanate(9.6%), based on susceptibility breakpoints established by the NCCLS, were markedly lower than these of penicillin. But, the resistant rate of cefaclor was very high, above 95%. Conclusion : We concluded that pneumococci isolated from study cases may be one of the world's highest penicillin resistant rates. But, amoxicillin and amoxicillin-clavulanate can be used as a first-line antibiotics. Finally, we hope that a continuous surveillance study to monitor resistant patterns of pneumococcal respiratory infections will be needed for the standard guidelines of empiric antibiotic treatment.

• Clinical and Experimental Pediatrics
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• v.48 no.9
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• pp.929-934
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• 2005

Purpose : This study describes how often complementary and alternative medical(CAM) therapies, what patterns of CAM therapies utilization, what types of CAM therapies and why CAM therapies are used in children and adolescent with chronic disease. Methods : We interviewed and filled out questionnaires with parents of patients suffering from asthma, atopic dermatitis, congenital myopathy, epilepsy and so on from Mar 2004 to Aug 2004. Results : Two hundred fifty two parents answered questionnaires; 160 cases(63.5 percent) had used CAM therapies. Utilization of CAM therapies according to each chronic disease was as follows : congenital myopathy(100 percent), atopic dermatitis(91.1 percent), asthma(72.5 percent), chronic diarrhea (50.0 percent), epilepsy(17.1 percent) etc. Types of CAM therapy were as follows : dietary supplement (31.1 percent), herb medicine(23.4 percent), massage(14.2 percent), acupuncture(4.6 percent) etc. Sixty four(40.0 percent) case underwent more than two types of CAM therapies simultaneously. One hundred thirty three(83.1 percent) case were asked through non-medical prescription. Ninety nine(61.9 percent) case were recognized positive effect of CAM therapies. Parents' and childrens' ages were influential factors in CAM therapies utilization : the older the parents and the younger the children, the higher the utilization. Conclusion : Although patients receive treatment with western medicine, many of them not only undergo CAM therapies, especially more than two types, but also recognize the positive effects of CAM therapies. As a result, we suggest that it is easy to use of CAM therapies, and the positive effects of CAM therapies are prominent, domestically. Therefore, medical approach and study about the effectiveness and side effects of CAM therapies is necessary to avoid the imprudent use of such therapies.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.2
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• pp.159-168
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• 2010

Objective: The purpose of this study was to evaluate the correlation between the expression pattern of vascular endothelial growth factor (VEGF) in endometrium and the pathogenesis of endometriosis by investigating VEGF expression patterns and their difference between eutopic endometrium of patients with endometriosis and that of normal controls without endometriosis. Methods: Endometrial sections were obtained from 64 hysterectomy specimens from women under age of 40, who had undergone hysterectomies and had histological evidence of endometriosis, with stage 3 and 4 according to the revised American Society for Reproductive Medicine classification. As for controls, 37 sections were gained from women diagnosed as having cervical intraepithelial neoplasia (CIN) of the uterine cervix and without evidence of pelvic endometriosis or adenomyosis during their operation. The VEGF content was evaluated immunohistochemically in the eutopic endometrium from 64 patients with endometriosis and 37 normal controls. Histological semiquantitative score (H-score) was calculated and compared between study group and control group throughout the menstrual cycle. Results: There was no significant difference in the H-score of VEGF in the eutopic endometrium between patients with endometriosis and controls without endometriosis when compared according to the same phase of the cycle, although the H-score of the study group was significantly higher in the secretory phase than the proliferative phase. Conclusion: The VEGF expression in the eutopic endometrium of women with endometriosis was not different from that of women without endometriosis. This study suggests VEGF expression in eutopic endometrium is unlikely associated with the pathogenesis of endometriosis.

• Journal of Chest Surgery
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• v.31 no.12
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• pp.1147-1158
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• 1998

Background: Portable cardiopulmonary bypass(CPB) technique has been used increasingly as a potent and effective option for emergency cardiopulmonary resuscitation(CPR) because it can maintain more stable hemodynamics and provide better survival than conventional CPR techniques. This study was designed to develop a prototype of Korean portable CPB system and, by applying it to CPR, to discriminate whether it would be superior to standard open-chest CPR. Material and Method: By using adult mongrel dogs, open-chest CPR(OCPR group, n=4) and portable-CPB CPR(CPB group, n=4) were compared with respects to restoration of spontaneous circulation(ROSC), hemodynamics, effects on blood cells, blood gas patterns, biochemical markers, and survivals. Ventricular fibrillation-cardiac arrest(VF-CA) of arrest(VF-CA) of 4 minutes followed by basic life support(BLS) of 15 minutes was applied in either group, which was standardized by the protocol of American Heart Association. Then, advanced life support(ALS) was applied to either group under the support of internal cardiac massage or CPB. ALS was maintained until ROSC was achieved but not longer than 30 minutes regardless of the presence of ROSC. All of the measured values were expressed as means±SD percent change from baseline. Result: During the early ALS, higher mean arterial pressure was maintained in CPB group than in OCPR group(90±19 vs. 71±32 %; p<.05) and lower mean pulmonary arterial pressure was also maintained in CPB group than in OCPR group(105±24 vs. 146±6%; p<.05). ROSC was achieved in all dogs. Post-ROSC levels of hematocrit, RBC, and platelet were decreased and plasma free hemoglobin was increased significantly in CPB group compared to OCPR group(p<.05). Changes in blood gas patterns, lactate, and CK-MB levels were not different between groups. Early mortality was seen in 3 dogs in OCPR group(survival time 31±36 hours) and 2 in CPB group(228±153 hours, p=ns). The remainders in both groups showed prolonged survival. Conclusion: These findings indicate that portable CPB can be effective to maintain stable hemodynamics during cardiac arrest, to achieve ROSC and to prolong survival. Further study is needed to refine the portable CPB system and to meet clinical challenges.

• Tuberculosis and Respiratory Diseases
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• v.50 no.6
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• pp.693-703
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• 2001

Background : Smoking is the most important and consistent determinant of the development and progression of COPD(Ed Note : Define COPD). The fact that cigarette smokers develop a different type of COPD, chronic bronchitis and emphysema, with different clinical and pathological aspects, suggests that the development of COPD has a relationship with other smoking-associated factors beyond just a simple smoking history. The aim of this was to analyze the smoking habits and history of patients with COPD and to evaluate the development of different types of COPD according to patient's smoking habits. Method : To evaluate the differences in the smoking patterns of patients with chronic bronchitis and emphysema, a pulmonary function test was conducted, and the smoking history and patterns was obtained through a smoking history questionnaire by a direct personal interview from 333 male cigarette smokers diagnosed with COPD, in the Yeungnam university medical center(190 patients diagnosed with chronic bronchitis, 143 patients diagnosed with emphysema). Result : The patients with emphysema smoked earlier and had a higher smoking history(ie, more packyears, more total amounts of smoked cigarette, and more deep inhalation and longer duration of plain cigarette exposure) than those with chronic bronchitis. The depth of inhalation was also significantly higher in the emphysema patients after taking into account age, cumulative cigarette consumption and the type of cigarette smoked. Conclusion : Emphysema was more associated with the increasing degree of inhalation as assessed by the depth of inhalation. A high alveolar smoke exposure may be a significant risk factor for the development of emphysema.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.2
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• pp.151-157
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• 2010

Purpose: The purposes of this study was to evaluates shear bond strength between zirconia core and veneer-ceramic in order to examine the clinical practice of colored zirconia block fabricated by infiltration method into the metal chloride solution. Material and methods: CNU block and $Everest{(R)}$ ZS blank were used. VITA In-$Ceram{(R)}$2000 YZ Coloring liquid (LL1) and 3 aqueous metal chloride solutions containing chromium and molybdenum ingredients were used. 40 zirconia specimens were prepared into cuboid shape ($5{\times}5{\times}10 mm$). All specimens were divided into 5 groups by infiltrating into the coloring liquids. After that, porcelain was build up into the shape of $5{\times}5{\times}4mm^3$, followed by sintering. The maximum loading and shear bond strength was measured. Failure patterns and failure sites were examined. Results: 1. There were no statistical differences in shear bond strength between zirconia blocks (P > .05). 2. There were no statistically significant differences in shear bond strength between non-colored and colored zirconia blocks, while shear bond strength of non-colored zirconia blocks is higher than that of colored specimen (P > .05). 3. In the comparison with shear bond strength among colored zirconia blocks, there were no statistical differences according to kinds of coloring liquid (P > .05). 4. Mixed failure patterns were mainly observed in the failure between zirconia and veneering ceramic. The veneering ceramic failure of all specimens was observed in either interface of zirconia or veneering ceramic. Conclusion: Shear bond strength between colored zirconia and veneering ceramic shows lower tendency than non-colored zirconia, but there was clinically allowable value.

• Clinical and Experimental Pediatrics
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• v.45 no.11
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• pp.1325-1331
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• 2002

Purpose : We tried to check the accuracy of references in the Journal of the Korean Pediatric Society and Journals of the Korean Pediatric Subspecialty Societies. We also wanted to know the citation patterns of authors by analyzing the frequency of cited materials. Methods : Three journals were randomly selected from the 2000 issues of Journal of the Korean Pediatric Society and nine journals were selected mainly from the second half of 2000 issues of each Journal of the Korean Pediatric Subspecialty Societies for the study. Then the accuracy of references was checked with Medline. Journals before 1964, books, and journals which were not written in English were used only in the citation pattern analysis. Results : Author errors were the most common(21.3%) among the reference elements. The next was title errors, followed by page errors, journal errors, volume errors and year errors. Total average error rate was 34.7% and we were unable to find journals in 89 cases(2.2%). The journal of the Korean Society of Neonatology had the lowest error rate(17.4%) and the journal of the Korean Pediatric Cardiology Society had the highest error rate(53.2%). The reference journals which were published and quoted in the most recent three years were only 612 cases(15%). Foreign journals were selected as reference(78.4%) more than domestic journals; The Journal of the Korean Pediatric Society was the most frequently cited reference(43.3%) among domestic journals. Conclusion : Authors are ultimately responsible for the accuracy of references and they should check the reference list with responsibility. Hopefully, authors also will have to use more domestic journals and recent journals.

• Journal of Oral Medicine and Pain
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• v.34 no.1
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• pp.63-79
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• 2009

While previous epidemiological studies on temporomandibular disorders (TMD) have been based on a given health center or population sample, no study has been performed on general population of Korea, especially concerning about treatment pattern such as clinician’s specialty involved in TMD treatment, types and amount of prescription medication and cost. This study aimed to investigate magnitude of health visits and treatment patterns for Korean patients with TMD through the computerized database of Health Insurance Review and Assessment Service (HIRAS). Inclusion criteria were all patients registered on the HIRAS database over 3 years' period from 2003 to 2005 and the medical records of patients with TMD as a main diagnosis were extracted. Information collected was as follows; distribution related to gender, age and region and type of hospital the patients visited, treatment duration, clinicians' specialty involved in treatment, cost, types of prescription medication and surgical treatment. The results of this study indicated that 0.15% of the population yearly sought TMD treatment, presenting with increase of incidence over the three years. Most of TMD patients were women (99.8%) and the biggest age group was second and third decades and decreased with age. Seoul and Kyeonggi province presented with higher incidence of TMD compared to the other regions of Korea, which seems to be related with magnitude of population. 56% of TMD patients visited primary care sector and the numbers of treatment visits was the highest in dental clinic (38.4%), followed by orthopedics (28%) and ENT (13.6%) clinics in order. Duration of prescription medication was the longest for anti-inflammatory analgesics, followed by antipsychotic drugs and muscle relaxants. Inpatient care related to TMD was primarily performed in dental hospital compared to medical hospital. Medical database of HIRAS provided comprehensive and vast information on epidemiologic characteristics and treatment patterns for patients seeking TMD treatment, which can be more reliable data to expect medical demand for TMD in condition that accurate diagnosis and standardized treatment is delivered in clinical settings.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.2
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• pp.243-254
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• 2002

For the purpose of evaluating the biocompatability of 3 kinds of metallic materials frequently used in pediatric dentistry (stainless steel crown, orthodontic band, orthodontic wire), cellular and molecular studies, including cell growth and proliferation, screening of cell death with determination of types whether necrosis or apoptosis and changes in expressions of related signaling molecules were examined, using cultured human gingival fibroblasts (HGF-1), HGF-1 was cultured in Dulbecco's modified Eagle's medium. among which the 3rd to 6th generations of HGF-1 were used. The specimen were divided into stainless steel crown (R), band (B) and wire (W). The immunocytochemical study was done for the detection of anti-PCNA (proliferating cell nuclear antigen) labeling. With extracted protein, western blot was done for the detection of ERK1/2, JNK, and p38, using individual antibodies. Cultured cells proliferated, remarkably till 7 day and slightly at 11 day. There was no statistical significance in the counts of proliferating HGF-1 between control and experimental groups (p>0.05). Relative growth rates were no statistically significant difference between control and experimental groups (p>0.05). PCNA labeling indexes showing similar patterns in control and experimental groups. The expressions of ERK1 and ERK2, p38 were similar in control and experimental groups. The expression of JNK increased at 1st day, slightly decreased at 4th day and markedly increased at 7th and 11 day. Although the patterns of control and experimental groups were similar, the increased expressions of JNK at late period suggest a possible stress due to inhibited cell growth and proliferation, and worse culture condition. Conclusively, the 3 kinds of metal specimens used in this study did not induce cellular and molecular hazards during short term culture of HGF-1. But, for the better clinical stability, the establishment of long period culture and animal experiment was thought necessary.