• Analytical Science and Technology
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• v.8 no.4
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• pp.545-551
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• 1995

Five acid hydrazides as precolumn fluorescence derivatization reagents for carboxylic acids in HPLC, which have the benzofuran or benzothiazole moiety conjugated to a furan, thiophene or oxazoline ring, were synthesized and examined in view of reactivity, separability and sensitivity. Of these hydrazides, 2-(5-hydrazinocarbonyl-2-oxazolyl)-5,6-dimethoxybenzothiazole (BTOH) was most favorable. The detection limit of lauric acid as a model acid was 0.1 pmol per $10-{\mu}l$ injection volume at S/N=3, which was roughly equal to that of an analogous compound, 2-(5-hydrazinocarbonyl-2-furyl)-5,6-dimethoxybenzothiazole. The reagent allowed rapid assays of carboxylic acids ($C_{12:0}-C_{20:4}$) within 20 min with satisfactory scparability. The method was applied to the determination of fatty acids in human sera from healthy volunteers as well as from patients with diabetes or thyroid dysfunction.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1993.05a
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• pp.70-70
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• 1993

Fundamental frequency is controlled by contraction of both TA and CT muscle. While activity of the CT is known well, little is known regarding the effect of the TA muscle on vocal fold vibration. To study this, a previously developed in vivo canine laryngeal model was modified. Isolated TA muscle activation was obtained by stimulating sectioned terminal TA branches through small thyroid cartilage windows. The results indicated that TA muscle activation is a major determinant in vocal register shift from falsetto to modal phonation. F0 increased with increasing TA activation in modal register, On the other hand, the F0 decreased with TA activation when the evoked voice belonged to falsetto register. Subglottic pressure increased gradually and OQ decreased gradually with TA activation.

• Journal of Korea Multimedia Society
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• v.21 no.12
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• pp.1363-1369
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• 2018

Breast cancer is one of the most common cancers in women worldwide. In Korea, breast cancer is most common cancer in women followed by thyroid cancer. The purpose of this study is to evaluate the possibility of using deep - run model for segmentation of breast masses and to identify the best deep-run model for breast mass segmentation. In this study, data of patients with breast masses were collected at Asan Medical Center. We used 596 images of mammography and 596 images of gold standard. In the area of interest of the medical image, it was cut into a rectangular shape with a margin of about 10% up and down, and then converted into an 8-bit image by adjusting the window width and level. Also, the size of the image was resampled to $150{\times}150$. In Deconvolution net, the average accuracy is 91.78%. In U-net, the average accuracy is 90.09%. Deconvolution net showed slightly better performance than U-net in this study, so it is expected that deconvolution net will be better for breast mass segmentation. However, because of few cases, there are a few images that are not accurately segmented. Therefore, more research is needed with various training data.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3368-3373
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• 2013

The purpose of this study was to analyze the risk factors of self-reported voice problem. Data were from the Korea National Health and Nutritional Examination Survey 2008. Subjects were 3,600 persons (1,501 men, 2,099 women) aged 19 years and older. A prediction model was developed by the use of a exhaustive CHAID (Chi Squared Automatic Interaction Detection) algorism of decision tree model. In the decision tree analysis, pain and discomfort during the last 2 weeks, age, the longest occupation and thyroid disorders was significantly associated with self-reported voice problem. The findings of associated factors suggest potential ways of targeting counseling and prevention efforts to control self-reported voice problem.

• The Journal of Internal Korean Medicine
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• v.31 no.3
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• pp.425-436
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• 2010

Objectives : Hypothyroidism is a relatively common endocrinologic disease, especially among older women. Western medical doctors treat hypothyroidism with levothyroxine, however there are several side effects, including thyrotoxicosis, atrial fibrillation, osteoporosis, etc. Therefore, traditional Korean medicine(TKM) offers an appealing alternative therapy for hypothyroidism. In this study, Cuscuta Semen was used to analyze its possible effect on a hypothyroidism rat model induced by propylthiouracil(PTU). Methods : 24 two-month-old Sprague-Dawley(SD) rats were divided into 4 groups: normal (n=6), PTU-induced hypothyroidism control(n=6), hypothyroidism rat treated with Cuscuta Semen (n=6), and hypothyroidism rat treated with levothyroxine(n=6). PTU was administered for 4 weeks, Cuscuta Semen and levothyroxine was administered 2 weeks after PTU was initiated for a total duration of 2 weeks. Blood samples from all the rats were taken from their hearts and analyzed. Results : When compared to the normal group, the PTU-induced control group showed significantly lower $T_4$, $T_3$ levels and significantly higher TSH level, which is indicative of hypothyroidism. The Cuscuta Semen group had significantly higher $T_4$ and significantly lower TSH than the control group(p<0.05). There was no significant difference in biochemical labs and weight between the Cuscuta Semen and control groups. Conclusions : These results suggest that Cuscuta Semen could be effective in increasing thyroid hormone production, and be powerful enough to affect the hypothalamus-pituitary-thyroid axis. Also, no adverse effects related with Cuscuta Semen were found, suggesting that it is relatively safe to administer. In conclusion, it seems that Cuscuta Semen is a safe alternative medicine for hypothyroidism.

• Journal of the Korean Society of Radiology
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• v.16 no.7
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• pp.843-849
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• 2022

In this study, the probability of secondary carcinogenesis was analyzed by measuring the exposure dose of surrounding normal organs during radiosurgery using a gamma knife. A pediatric phantom (Model 706-G, CIRS, USA) composed of human tissue-equivalent material was set to four tumor volumes of 0.25 cm³, 0.51 cm³, 1.01 cm³, and 2.03 cm³, and the average dose was 18.4 ± 3.4 Gy. After installing the Rando phantom on the table of the gamma knife surgical equipment, the OSLD nanoDot dosimeters were placed in the right eye, left eye, thyroid, thymus gland, right lung, and left lung to measure each exposure dose. The probability of cancer occurrence due to radiation exposure of surrounding normal organs during gamma knife radiosurgery for acoustic schwannoma disease was 4.08 cancers per 100,000 at a tumor volume of 2.03 cm³. This study is expected to be used as useful data in relation to stochastic effects in the future by studying the risk of secondary radiation exposure that can occur during stereotactic radiosurgery.

• Radiation Oncology Journal
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• v.17 no.3
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• pp.187-194
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• 1999

Purpose : The aim of this study is to look for the possible efficacy of external irradiation for locally advanced papillary thyroid cancers (stage pT4 or Nl ). Methods and Materials : From August 1981 through September 1997, 91 Patients with locally advanced papillary thyroid cancers (stage pT4 or Nl ) have been treated with external irradiation and followed up at our clinic. All of the patients have been treated with surgical resection. After surgery, 23 patients received postoperative external irradiation with or without ablative radioiodine therapy, whereas the other 68 patients were treated with ablative radioiodine therapy alone. Distributions of sex, age, and stage were comparable in both irradiated and nonirradiated groups. Multivariate analysis of the influence by age, sex, stage, ablative radioiodine therapy and external irradiation on local control were peformed by using Cox's proportional hazard model. Results : Overall survival rates at 7 years were of no significant difference in both groups. There were $98.1\%$ for no RT group and $90\%$ for RT group (p=0.506). 5-year local control rates were significantly different, these were $95.2\%$ for RT group and $67.5\%$ for no RT group (p=0.0408). An analysis of the prognostic factors, age, sex, stage, and RAI were not significant variables, except for the external irradiation. Conclusion : Adjuvant postoperative external irradiation did not affect overall survival, but significantly improved local control in the patients with locally advanced papillary thyroid cancers (stage pT4 or lympy node involvement).

• Journal of Radiation Protection and Research
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• v.19 no.3
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• pp.199-208
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• 1994

The derived intervention levels in Korean foodstuffs were estimated using the dynamic ingestion pathway model which was developed considering Korean environment. The derived intervention levels were estimated from the intervention level of dose based on the thyroid committed dose equivalent of infant in the case of I-131, and the whole body committed dose equivalent for age groups and 13 kinds foodstuffs in the cases of Cs-137 and Sr-90. The derived intervention levels were shown as a considerable variation with deposition time and radionuclide. The adult was the most important age group in the estimation of derived intervention levels for Cs-137 and Sr-90. In the adult, the derived intervention levels for rice were 2390 and 47 Bq/kg for Cs-137 and Sr-90 in the case of deposition in summer, respectively, and 198 and 79 Bq/kg in the case of deposition in winter, respectively.

• Clinical and Experimental Reproductive Medicine
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• v.44 no.1
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• pp.28-32
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• 2017

Objective: Growing evidence suggests that increased cardiovascular disease (CVD) risk is associated with female infertility caused by conditions such as polycystic ovarian disease, obesity, thyroid dysfunction, and endometriosis. The aim of this study was to evaluate whether any relationship exists between CVD and unexplained infertility. Methods: Sixty-five women with unexplained infertility and 65 fertile controls were enrolled in the study. CVD risk markers such as low-density lipoprotein (LDL), high-density lipoprotein (HDL), total cholesterol (TC), triglycerides (TG), insulin resistance (defined by the homeostasis model assessment ratio), and high-sensitivity C-reactive protein (hs-CRP) were assessed. Results: TG, TC, LDL, and hs-CRP levels were higher and HDL levels were lower in patients with unexplained infertility than in fertile controls (p<0.05 for all). Positive associations were found between unexplained infertility and TG, TC, LDL, and hs-CRP levels, and a negative correlation was found for HDL (p<0.05 for all). Multivariate logistic regression analysis showed that TG, HDL, and hs-CRP were independent variables associated with unexplained infertility. Conclusion: Our study showed that women with unexplained infertility had an atherogenic lipid profile and elevated hs-CRP levels, suggesting a higher risk of developing CVD in the future. Further studies with larger groups are needed to investigate the nature of this link.

• The Korean Journal of Zoology
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• v.36 no.4
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• pp.487-495
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• 1993

TRH (Thvrotropin-Releasing Hormone) known to regulate the transcription of the TSH (Thyroid-Stimulating Hormones gene in pituitary cells, but little is understood about the mechanism(sl involved. re present study was attempted to elucidate the role of Ca2+ movement through the voltage-gated channels in the regulation of TSH gene transcription. The c-fos is one of immediate early genes and used as model system for the investigation of signaling pathwavs involved in various stimuli. The changes of c-fos mRNA levels were determined after treatment of various agents using Northern and slot hybridization analysis. The c-fos mRNA was rapidly and transiently induced by TRH (about 3-fold) in GH3 cells and this induction was repressed by calcium chelating agent (EGTA), calcium channel blocker (verapamil) anti protein kinase C inhibitor (aminoacridine). The abilities of forskolin (adenvlate cvclase activators, PMA (protein kinase C activator), and A23187 (calcium ionophore) to affect c-ios gene transcription, either alone or in combination with TRH were tested in the same cells. All of them significantly increased the level of c-fos mRUA. However, no additive relationship was observed in all combined treatments except forskolin. These results suggest that TRH action on the c-fos gene activation is mediated by calcium influx as well as through protein kinase C.