• Journal of the Korean Society of Radiology
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• v.17 no.6
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• pp.843-849
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• 2023

This study attempted to determine the optimal algorithm after quantitatively analyzing noise, SNR, and CNR measurements by reconstructing four algorithms (Standard, Soft, Bone, and Detail) from head and neck CT images of patients who underwent implant surgery. As an analysis method, pixel values were calculated through the region of interest in the reconstructed image using the Image J program. For noise, SNR, and CNR, the region of interest was measured at the location of the pharynx, masseter muscle, and parotid gland in the image, and the mean and SD values were obtained. The values of SNR and CNR were calculated based on the given formula. As a result, the standard algorithm showed the lowest noise and the highest SNR. CNR was highest in the Soft algorithm, but showed no significant difference from the Standard algorithm. Therefore, it is believed that the Standard algorithm is the optimal algorithm for examining patients wearing intraoral implants in head and neck CT examinations. We hope that the data from this study will be used as basic data for image evaluation in head and neck CT examinations, and that the quality of images will be further improved through various algorithm changes. It is believed that this will be an opportunity to do so.

• Journal of the Korean Society of Radiology
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• v.17 no.6
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• pp.865-872
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• 2023

The purpose of this study was to analyze fabrics suitable for use as examination gowns to determine whether examination gowns affect imaging during anterior to posterior chest examinations(Chest AP) on a digital X-ray system. Examination gowns in use at five medical centers in Seoul were collected and included modal, tencel, cotton, and rayon fabrics. The selection of fabrics was based on studies that reported fabrics with good tactile, absorbent, stretchable, and wrinkle resistance. Phantoms of five hospital gowns and four fabrics, arranged in overlapping layers from one to eight, were created and examined on a digital X-ray system in both Chest AP examination. The images examined were subjected to a first-step profile analysis, a second-step signal intensity averaging analysis, and a third-step microscopic analysis. The results showed that all nine materials had an increasing impact on the image as the number of layers of fabric increased, with the modal fabric having the least impact on the image in the first, second, and third analyses. In conclusion, as the resolution of digital x-ray systems increases, the impact of examination clothing on the image will increase, and research to find suitable materials for examination clothing will continue to be necessary.

• Toxicological Research
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• v.8 no.2
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• pp.235-253
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• 1992

A subacute toxicity study of cis-Malonato[(4R,5R)-4,5-bis(aminomethyl)-2-isopropyl-1,3-dioxolane]platinum(II)(SKI 2053R) was carried out to obtain information on its toxicological profiles, and to determine the maximum tolerated dose in beagle dogs. Four groups of beagle dogs (2M and 2F per group, 0,0.5,1.0,2.0mg/kg/day)were given 15 i.v. injections of SKI 2053R. In order to compare the toxic effects of SKI 2053R with those of cisplatin, one group was treated with cisplatin(0.7mg/kg/day)according to the same treatment schedule. The dosing schedule was divided into 3 courses of 5 consecutive days with 23-day dose-free intervals between each course. After completion of the treatments, remaining dogs were necropsied under established guidelines. Three of four dogs in the high dose group and one of four dogs in the middle dose group treated with SKI 2053R died of hypovolemic shock secondary to hemorrhagic and ulcerative enterocolitis. No toxicity-related mortality occurred in the low dose group of SKI 2053R. No survivor was observed in the group of cisplatin. Clinical signs including vomiting, diarrhea, anorexia and loss body weight were apparent in dogs given either cisplatin or high and middle doses of SKI 2053R. Severe thrombocytopenia and leukocytopenia were observed in the high dose group of SKI 2053R and cisplatin-treatment group, while toxicities as bone marrow suppression were reversible. The significant elevation of serum ALP values in group of SKI 2053R(2.0 mg/kg/day and 1.0mg/kg/day) and cisplatin(0.7mg/kg/day)was observed. Slight proteinuria waa observed in high and middle dose level groups of SKI 2053R. In histopathological examinations, pathological alterations of liver, kidney and spleen were noted dose-dependantly in dogs treated with SKI 2053R, and there was no overt sign of toxicity in low dose group of SKI 2053R. Compared to SKI 2053R, more severe durg-related toxicities occurred in dogs treated with cisplatin. It waw estimated that maximum tolerated dose of SKI 2053R in this treatment schedule was 0.5~0.7mg/kg/day. In conclusion, overall toxic potential of SKI 2053R was approximately 3 times lower than that of cisplatin with respect of lethality.

• Korean Journal of Radiology
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• v.25 no.6
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• pp.511-517
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• 2024

Objective: To prospectively investigate the influence of the menstrual cycle on the background parenchymal signal (BPS) and apparent diffusion coefficient (ADC) of the breast on diffusion-weighted MRI (DW-MRI) in healthy premenopausal women. Materials and Methods: Seven healthy premenopausal women (median age, 37 years; range, 33-49 years) with regular menstrual cycles participated in this study. DW-MRI was performed during each of the four phases of the menstrual cycle (four examinations in total). Three radiologists independently assessed the BPS visual grade on images with b-values of 800 sec/mm² (b800), 1200 sec/mm² (b1200), and a synthetic 1500 sec/mm² (sb1500). Additionally, one radiologist conducted a quantitative analysis to measure the BPS volume (%) and ADC values of the BPS (ADC_BPS) and fibroglandular tissue (ADC_FGT). Changes in the visual grade, BPS volume (%), ADC_BPS, and ADC_FGT during the menstrual cycle were descriptively analyzed. Results: The visual grade of BPS in seven women varied from mild to marked on b800 and from minimal to moderate on b1200 and sb1500. As the b-value increased, the visual grade of BPS decreased. On b800 and sb1500, two of the seven volunteers showed the highest visual grade in the early follicular phase (EFP). On b1200, three of the seven volunteers showed the highest visual grades in EFP. The BPS volume (%) on b800 and b1200 showed the highest value in three of the six volunteers with dense breasts in EFP. Three of the seven volunteers showed the lowest ADC_BPS in the EFP. Four of the seven volunteers showed the highest ADC_BPS in the early luteal phase (ELP) and the lowest ADC_FGT in the late follicular phase (LFP). Conclusion: Most volunteers did not exhibit specific BPS patterns during their menstrual cycles. However, the highest BPS and lowest ADC_BPS were more frequently observed in EFP than in the other menstrual cycle phases, whereas the highest ADC_BPS was more common in ELP. The lowest ADC_FGT was more frequent in LFP.

• Advances in Traditional Medicine
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• v.5 no.4
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• pp.336-346
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• 2005

Experts of Sasang Constitution Medicine of Traditional Korean Medicine have classified stroke patients with four types of Sasang constitutions in their clinical practice and some types of Sasang constitutions have been regarded as risk factors of stroke, but this is uncertain because there were no evidences by large scale of prospective studies. The purpose of this was to study the association between strokes and Sasang constitutions. Case-control study has been conducted to the patients admitted to the research hospitals. The patients were confirmed stroke by brain MRI or CT scans and recruited from May 2003 to August 2005. The subjects who met the requirement of inclusion and exclusion criteria were 108 patients as the cases and 107 as healthy controls. Data collection has been performed by the trained specialists majoring neurologists through interviews, physical examinations, and laboratory testes. No statistical significance was obtained between the strokes and Sasang constitutions, yet Taeumin, and Soyangin types showed a trend of increase in the incidence of strokes as compared with Soeumin. To acquire more concrete data on this theme, we need further and large scale of prospective researches.

• Quality Improvement in Health Care
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• v.4 no.1
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• pp.36-49
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• 1997

Background : Hypertension is one of the most important risk factors of the cerebrovascular accident and coronary artery disease which are the major causes of mortality in Korea. In Korea, the quality of care provided by office-based physicians has not been evaluated formally. The purpose of this study is to assess the quality of hypertension management of office-based physicians. Method : Self-administered questionnaires were mailed to the office-based physicians with the speciality of internal medicine, general surgery, family medicine, and general practitioners. Among 2,045 physicians, 981 doctors(48.0%) replied the questionnaires. Contents of questionnaires were based on the recommendation from the JNC-V report(the Fifth Report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure), and included the criteria of diagnosis, treatment, follow-up interval, and other characteristics of physicians(age, sex, type of speciality, and location of practice). Results : Eighty four percent of the office-based physicians made diagnosis of hypertension with less than 3 times of blood pressure measurements. The performance rate of required examination for hypertensives was very low in most items. Rate of fundoscopic examination is the lowest one among them(5.9%). The performance rate of laboratory examination was also low in most items. Internists tended to order more frequent laboratory examinations than any other type of physicians. Only 11.4% of the physicians did appropriate treatments for the mild hypertension case. The antihypertensives selected by the physicians as a first line drug were in the order of beta blocker(26.4%), calcium channel blocker(23.4%), diuretics(23.1%), ACE inhibitors(14.3%). The visit interval for established hypertensives was very short. Proportion of physicians with follow-up interval longer than 4 weeks was only 4.3%. Conclusions : The overall quality of hypertension management of office-based physicians in Korea is very problematic in many aspects. So further investigations to find out the reasons of low quality arid quality of care should be initiated.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.1
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• pp.147-159
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• 2000

The NIOSH health hazard evaluation program (HHE program) was created in response to the mandate to determine the toxic effect and potential health hazard of workplace exposure, which is found in Occupational Safety and Health Act of 1970 and the Federal Mine Safety and Health Act of 1977, A primary benefit of HHE program is its ability to provide current health hazard data to employers and employees, which assists them in identifying solutions to occupational health and safety problems in their workplaces, The HHE program also stimulates research in the development and review of sampling methods and diagnostic tests and may prompt additional exposure assesment efforts and toxicological and epidemiological studies. HHE projects also provide human exposure-toxicity data that are used to asses the validity of existing occupational health standards and to support criteria for new standards of recommendation, The HHE request is classified into four categories: 1) category 1: As a administratively invalid, 2) category 2: These are valid requests for which a site visit is not essential to an appropriate response, 3) Category 3 : These are valid requests for which a site visit is necessary for an adequate evaluation, 4) These are valid request which present a complex problem or an opportunity for research, To carry out HHE program one or methods of investigation might be used: 1) direct observation and evaluation of production processes and employee work practices 2) employees exposure level and air contamination level 3) medical test or physical examinations of employees 4) private, confidential interviews with employees 5) review of employer's record of injuries and illness, employee exposure data, medical tests and job histories. After investigation and analysing the data, NIOSH issues a final report, giving finding and recommendation.

• Journal of Pharmacopuncture
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• v.17 no.2
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• pp.7-17
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• 2014

Objectives: Condurango is widely used in various systems of complementary and alternative medicines (CAM) against oesophageal and stomach ailments including certain types of cancer. However, until now no systematic study has been conducted to verify its efficacy and dose with proper experimental support. Therefore, we examined if ethanolic extract of Condurango could ameliorate benzo[a]pyrene (BaP)-induced lung cancer in rats, in vivo to validate its use as traditional medicine. Methods: Fifteen male and 15 female Sprague-Dawley (SD) rats were treated with 0.28 mg/kg of Sweet Bee Venom (SBV) (high-dosage group) and the same numbers of male and female SD rats were treated with 0.2 mL/kg of normal saline (control group) for 13 weeks. We selected five male and five female SD rats from the high-dosage group and the same numbers of male and female SD rats from the control group, and we observed these rats for four weeks. We conducted body-weight measurements, ophthalmic examinations, urinalyses and hematology, biochemistry, histology tests. Results: A histological study revealed gradual progress in lung tissue-repair activity in Condurango-fed cancer-bearing rats, showing gradual tissue recovery after three months of drug administration. Condurango has the capacity to generate reactive oxygen species (ROS), which may contribute to a reduction in anti-oxidative activity and to an induction of oxidative stress-mediated cancer cell-death. Condurango-activated pro-apoptotic genes (Bax, caspase-3, caspase-9, p53, cytochrome-c, apaf-1, ICAD and PARP) and down-regulated antiapoptotic-Bcl-2 expression were noted both at mRNA and protein levels. Studies on caspase-3 activation and PARP cleavage by western blot analysis revealed that Condurango induced apoptosis through a caspase-3-dependent pathway. Conclusion: The anticancer efficacy of an ethanolic extract of Condurango for treating BaP-induced lung cancer in rats lends support for its use in various traditional systems of medicine.

• Journal of Pharmacopuncture
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• v.17 no.2
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• pp.18-26
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• 2014

Objectives: This study was performed to check for reversibility in the changes induced by a 13-week, repeated, dose toxicity test of Sweet Bee Venom (SBV) in Sprague-Dawley (SD) rats. Methods: Fifteen male and 15 female SD rats were treated with 0.28 mg/kg of SBV (high-dosage group) and the same numbers of male and female SD rats were treated with 0.2 mL/kg of normal saline (control group) for 13 weeks. We selected five male and five female SD rats from the high-dosage group and the same numbers of male and female SD rats from the control group, and we observed these rats for four weeks. We conducted body-weight measurements, ophthalmic examinations, urinalyses and hematology, biochemistry, histology tests. Results: (1) Hyperemia and movement disorder were observed in the 13-week, repeated, dose toxicity test, but these symptoms were not observed during the recovery period. (2) The rats in the high-dose group showed no significant changes in weight compared to the control group. (3) No significant differences in the ophthalmic parameters, urine analyses, complete blood cell counts (CBCs), and biochemistry were observed among the recovery groups. (4) No changes in organ weights were observed during the recovery period. (5) Histological examination of the thigh muscle indicated cell infiltration, inflammation, degeneration, necrosis of muscle fiber, and fibrosis during the treatment period, but these changes were not observed during the recovery period. The fatty liver change that was observed during the toxicity test was not observed during the recovery period. No other organ abnormalities were observed. Conclusion: The changes that occurred during the 13-week, repeated, dose toxicity test are reversible, and SBV can be safely used as a treatment modality.

• The korean journal of orthodontics
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• v.22 no.2 s.37
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• pp.345-372
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• 1992

The purpose of this experiment was to study the effects of changes of mandibular position on temporomandibular joint in internal derangement patients Twenty-four female New Zealand White Rabbits, weighing over 3.5kg, were utilized in this study . Bilateral temporomandibular joint surgery was performed in twenty-one of the rabbits to displace disc anteriorly through incising the retrodiscal tissue 1-2mm posterior to the disc, thus inducing internal derangement. They were divided into three groups nine were left untreated after surgery, six were fitted with functional protrusive appliances 4 weeks after surgery, and six wore collar appliances to apply 4 ounces of mandibular refractive force per side 4 weeks after surgery. The remaining three served as the control group. Histologic examinations were performed after sacrificing them by threes at 4-week intervals. The results were as follows. 1. Histologic findings similar to internal derangement were observed in the rabbits whose retrodiscal tissues had been incised. 2. In the rabbits untreated after surgery, articular surface on condylar process and articular eminence showed severe erosion and deformation, and displaced disc manifested changes in both shape and internal architecture. 3. Functional protrusion after surgery resulted in progressive remodeling on postero-superior portion of condyle and glenoid fossa, while it also brought about erosion on articular eminence and anterior portion of condyle. 4. Mandibular retraction after surgery resulted in compression of retrodiscal tissue and regressive remodeling of posterior portion of condyle.