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Background: The mainstay of treatment for early-stage cervical cancer is surgery; we present a 5-year experience of robotic single-site radical hysterectomy (RSRH) focused on surgical and oncologic outcomes. Methods: This retrospective study included 44 cases of RSRH performed in patients with early-stage cervical cancer. Results: The median follow-up period for the 44 patients was 34 months. The mean total operation time was 156.07 ± 31.77 min, while mean console time was 95.81 ± 24.95 min. Two cases had complications, which required surgical management, while four cases (9.1%) exhibited recurrence. The disease-free survival rate at 5 years was 90.9%. The sub-division analysis showed that Stage Ia2 and stage Ib1 patient sub-group showed better DFS than that of the stage Ib2 patient sub-group. The learning curve analysis showed that the CUSUM-T initially peaks at the sixth case then gradually decreases before rising and peaking at the 24th case. After 24th case, the CUSUM-T gradually decreases and reaches zero. Conclusion: The surgical outcomes of RSRH for early-stage cervical cancer treatment were safe and acceptable. However, RSRH could be considered carefully only in well-selected patient groups. Large-scale prospective studies are necessary in the future to validate the results.

The National Institute of Meteorological Sciences-Korea Meteorological Administration (NIMS-KMA) has participated in the Coupled Model Inter-comparison Project (CMIP) and provided long-term simulations using the coupled climate model. The NIMS-KMA produces new future projections using the ensemble mean of KMA Advanced Community Earth system model (K-ACE) and UK Earth System Model version1 (UKESM1) simulations to provide scientific information of future climate changes. In this study, we analyze four experiments those conducted following the new shared socioeconomic pathway (SSP) based scenarios to examine projected climate change in the twenty-first century. Present day (PD) simulations show high performance skill in both climate mean and variability, which provide a reliability of the climate models and reduces the uncertainty in response to future forcing. In future projections, global temperature increases from 1.92 °C to 5.20 °C relative to the PD level (1995–2014). Global mean precipitation increases from 5.1% to 10.1% and sea ice extent decreases from 19% to 62% in the Arctic and from 18% to 54% in the Antarctic. In addition, climate changes are accelerating toward the late twenty-first century. Our CMIP6 simulations are released to the public through the Earth System Grid Federation (ESGF) international data sharing portal and are used to support the establishment of the national adaptation plan for climate change in South Korea.

As one of the main drivers for climate change, it is important to understand changes in anthropogenic aerosol emissions and evaluate the climate impact. Anthropogenic aerosols have affected global climate while exerting a much larger influence on regional climate by their short lifetime and heterogeneous spatial distribution. In this study, the effective radiative forcing (ERF), which has been accepted as a useful index for quantifying the effect of climate forcing, was evaluated to understand the effects of aerosol on regional climate over a historical period (1850&ndash, 2014). Eastern United States (EUS), Western European Union (WEU), and Eastern Central China (ECC), are regions that predominantly emit anthropogenic aerosols and were analyzed using Coupled Model Intercomparison Project 6 (CMIP6) simulations implemented within the framework of the Aerosol Chemistry Model Intercomparison Project (AerChemMIP) in the UK&rsquo, s Earth System Model (UKESM1). In EUS and WEU, where industrialization occurred relatively earlier, the negative ERF seems to have been recovering in recent decades based on the decreasing trend of aerosol emissions. Conversely, the radiative cooling in ECC seems to be strengthened as aerosol emission continuously increases. These aerosol ERFs have been largely attributed to atmospheric rapid adjustments, driven mainly by aerosol-cloud interactions rather than direct effects of aerosol such as scattering and absorption.

// Se Young Jang 1, * , Gyeonghwa Kim 2, * , Soo Young Park 1 , Yu Rim Lee 1 , Sang Hoon Kwon 1 , Hyeong Seok Kim 1 , Jun Sik Yoon 1 , Jun Seob Lee 1 , Young-Oh Kweon 1 , Heon Tak Ha 3 , Jae Min Chun 3 , Young Seok Han 3 , Won Kee Lee 4 , Jun Young Chang 5 , Jung Gil Park 6 , Byungheon Lee 2 , Won Young Tak 1 and Keun Hur 2 1 Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Republic of Korea 2 Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, School of Medicine, Kyungpook National University, Daegu, Republic of Korea 3 Department of Surgery, Kyungpook National University School of Medicine, Daegu, Republic of Korea 4 Biostatistics, Medical Research Collaboration Center in Kyungpook National University Hospital, Kyungpook National University School of Medicine, Daegu, Republic of Korea 5 Department of Neurology, Gyeongsang National University Changwon Hospital, Changwon, Republic of Korea 6 Department of Internal Medicine, College of Medicine, Yeungnam University, Daegu, Republic of Korea * These authors contributed equally to this work Correspondence to: Keun Hur, email: KeunHur@knu.ac.kr Won Young Tak, email: wytak@knu.ac.kr Keywords: hepatocellular carcinoma, long noncoding RNA ATB, survival, prognosis, epithelial mesenchymal transition Received: June 28, 2017 Accepted: September 04, 2017 Published: September 20, 2017 ABSTRACT Hepatocellular carcinoma (HCC) is a worldwide health problem and it is important to understand the mechanistic roles of the biomolecules involved in its pathogenesis. Long non-coding RNAs (lncRNAs) are frequently and aberrantly expressed in various human cancers and are known to play a role in cancer pathogenesis. The aim of this study was to analyze the expression of lncRNA-ATB in HCC and investigate the implications for prognoses. In total, 100 samples of HCC tissues and their corresponding, adjacent, non-cancerous liver tissues were collected. Total RNAs were extracted and the expression levels of lncRNA-ATB were measured by qRT-PCR. The association of lncRNA expression with clinicopathological features and patient survival were then analyzed. LncRNA-ATB was significantly upregulated in HCC tissues compared with the levels in corresponding non-cancerous tissues. Expression of lncRNA-ATB was significantly associated with portal vein thrombosis, intrahepatic or extrahepatic metastases, mUICC stage, and the BCLC stage. Large tumors (> 5 cm, HR = 3.851, 95% CI = 1.431–10.364, p = 0.008) and higher lncRNA-ATB expression (HR = 4.158, 95% CI = 1.226–14.107, p = 0.022) were the significant prognostic factors for overall survival. With this novel evidence of the involvement of lncRNA-ATB in HCC pathogenesis and clinical features, lncRNA-ATB can be concluded to have potential as a biomarker for the prognosis of HCC and as a targeted therapy for afflicted patients.

In 2016, 9-valent human papillomavirus (HPV) vaccine has been newly introduced in Korea, thus the need to develop recommendations for the vaccine has raised. Until we decide to develop a guideline, no further studies on the bi-valent or quadri-valent HPV vaccine have been announced. We searched and reviewed the literatures focused on the efficacy of 9-valent HPV vaccine, the ideal age of 3-dose schedule vaccination, the efficacy of 9-valent HPV vaccine in middle-aged women, the efficacy of the 2-dose schedule vaccination, the safety of 9-valent HPV vaccine, the possibility of additional 9-valent HPV vaccination, and cross-vaccination of 9-valent HPV vaccine. So, Korean Society of Gynecologic Oncology (KSGO) developed a guideline only for 9-valent HPV vaccine.

급성 심근경색은 소아나 젊은 연령에서는 매우 드문 질환이지만 몇몇 기저질환을 가지고 있는 경우 그 발병률이 증가할 수 있고 신증후군도 그 원인 중의 하나이다. 신증후군에서 나타나는 응고항진상태와 동맥경화의 악화가 급성 심근경색의 원인으로 제시되고 있다. 본 증례는 잘 조절되지 않는 미세변화 신증후군을 가지는 젊은 환자에서 발생한 심인성 쇼크를 동반한 ST상승 심근경색을 보고하였다.

Dermatomyositis (DM) is an idiopathic inflammatory myopathy (IIM) characterized by skeletal muscle inflammation and typical skin manifestations. Creatine kinase (CK) has traditionally been considered to be the most useful serum enzyme for the diagnosis and assessment of adult patients with IIM. To our knowledge, there has been no reported case of biopsy-proven DM without CK elevation in Korea, to date. Panniculitis is an uncommon cutaneous manifestation in adult patients with DM. A search of the PubMed database reveals fewer than 30 reported cases of panniculitis in adult patients with DM. Here, we report a case of a 42-year-old female who was diagnosed with biopsy-proven DM with normal serum CK levels and panniculitis. (Korean J Med 2016;90:274-279)

This study aims to improve the forecasting skill for freezing precipitation. A total of 102 freezing precipitation cases were collected in South and North Korea from 2001 onwards. Temperature fields on the ground and in the atmosphere, vertical temperature profiles, geopotential fields, thickness fields and their spatiotemporal variations, and their combinations using the predominant precipitation-type nomograms (P-type nomograms) were classified and investigated to determine whether or not these data could be used as predictors. Results show that 1) the combination of the thicknesses of 1000-850 hPa and 850-700 hPa is recommended for the P-type nomograms for Korea, which is different from that used in the United States in threshold values; 2) 35 out of 72 synoptic situations are possible conditions for freezing precipitation; and 3) 3 groups out of those 35 situations, i.e., the 1000 hPa warmfront group, the mid-level southerly category of 850 hPa, and the mid-layer warm type in the vertical temperature profile, show the greatest frequency. Freezing precipitation occurs only in a small part of a possible area. Therefore, despite the increasing observations in the year-on-year trend, only a few of the cases have been detected. The possibility of observation errors is also one of the biggest problems. Therefore, the need for new equipment, such as a freezing rain detector (FRAD), to detect the phenomenon automatically is required and proposed. A denser observing system of FRADs and an ultra-fine gridded numerical model are suggested as a solution for the prediction of freezing precipitation.

Objective: To measure the prognostic value of the lymphocyte-monocyte ratio (LMR) in patients with epithelial ovarian cancer (EOC). Methods: We retrospectively examined the LMR as a prognosticator in a cohort of 234 patients with EOC who underwent surgical resection. Patients were categorized into two different groups based on the LMR (LMR-low and LMR-high) using cut-off values determined by receiver operating characteristic (ROC) curve analysis. The objective of the study was to assess the effect of the LMR on progression-free survival (PFS) and overall survival (OS), and to validate the LMR as an independent predictor of survival. Results: Using the data collected from the whole cohort, the optimized LMR cut-off value selected on the ROC curve was 2.07 for both PFS and OS. The LMR-low and LMR-high groups included 48 (20.5%) and 186 patients (79.5%), respectively. The 5-year PFS rates in the LMR-low and LMR-high groups were 40.0 and 62.5% (P < 0.0001), respectively, and the 5-year OS rates in these two groups were 42.2 and 67.2% (P < 0.0001), respectively. On multivariate analysis, we identified age, International Federation of Gynecology and Obstetrics (FIGO) stage, and cancer antigen 125 levels to be the strongest valuable prognostic factors affecting PFS (P = 0.0421, P = 0.0012, and P = 0.0313, respectively) and age, FIGO stage, and the LMR as the most valuable prognostic factors predicting OS (P = 0.0064, P = 0.0029, and P = 0.0293, respectively). Conclusion: The LMR is an independent prognostic factor affecting the survival of patients with EOC.

This study analyzes the relationship between various atmospheric fields and the observed PM10 concentrations in the Seoul metropolitan area, South Korea, during the winters of the 2001&ndash, 2014 period to find suitable atmospheric indices for predicting high PM10 episodes in the region. The analysis shows that PM10 concentration in the metropolitan area is mainly affected by the intensity of horizontal ventilation and the 500 hPa high-pressure system over the Korean peninsula. The modified Korea particulate matter index (MKPI) is proposed based on a 10 m wind speed for surface ventilation and 500 hPa zonal wind for the intensity of a 500 hPa high-pressure system over the Korean peninsula. It is found that a positive MKPI value is closely correlated with the occurrence of high PM10 concentration episodes, and hence, can be used as a predictor for high PM10 episodes in the area. A future projection of the MKPI using two three-member general circulation model (GCM) ensembles with four shared socioeconomic pathway (SSP) scenarios in Coupled Model Intercomparison Project Phase 6 (CMIP6) shows that positive MKPI events and high PM10 episodes are expected to increase by 5.4%&minus, 16.4% depending on the SSP scenarios in the 2081&minus, 2100 period from the present-day period of 1995&minus, 2014.

To compare the operative outcomes of patients undergoing either single-port or multiport laparoscopic hysterectomy (LH).Two hundred fifty-six women scheduled for LH for symptomatic myoma and/or adenomyosis from 8 tertiary teaching hospitals were randomized to single-port or multiport groups. Primary outcome was conversion and/or complication proportion of the planned procedure to determine whether the success proportion of the single-port approach was not inferior to that of the multiport approach. Secondary outcomes were postoperative pain and operative scar.Demographic parameters including age, body mass index, parity, and history of vaginal and cesarean delivery were comparable between the 2 groups. The primary outcome of a combined conversion and/or complication rate was similar between the single-port and multiport groups at 8% and 10.3%, respectively. Conversions were similar between the groups with 4% of single-port cases and .8% of multiport cases. Transfusions were the most frequent complication required in 4.0% of single-port cases and 7.9% of multiport cases, with no difference between the groups. Concerning secondary outcomes, postoperative pain score and patient and observer scar assessment were not different between the 2 groups. Although not a specific outcome measure, there was no difference between the groups in blood loss, operative time, and postoperative hospital stay.Single-port LH is not inferior to multiport LH in terms of conversion and/or complications rates, including transfusion. However, the single-port approach did not have any advantage over multiport LH with regard to pain or cosmetic outcomes. These findings were demonstrated by multi-institutional surgeons in Korea.

Background The optimal endoscopic screening interval for early gastric cancer (EGC) detection still remains controversial. Thus, we performed this prospective study to clarify the optimal interval between endoscopic examinations for EGC detection. Methods A questionnaire survey for penultimate endoscopy and gastric cancer (GC) diagnosis interval was used; the findings were then analyzed. The patients were divided into two groups according to GC type and endoscopic examinations intervals. Results A total of 843 patients were enrolled. The endoscopic GC detection interval (P < 0.001), tumor location (P < 0.001), tumor size (P < 0.001), histology (P < 0.001), tumor stage (P < 0.001), and treatment modality (P < 0.001) showed significant differences in the univariate analysis between EGC and advanced gastric cancer (AGC). Endoscopic examination intervals below 2 years and 3 years were associated with higher proportions of EGC detection (adjusted odds ratio, 2.458 and 3.022, respectively) (P < 0.001). The patients with endoscopic examination to GC diagnosis interval of < 2 years showed significant differences in tumor size (P < 0.001), tumor stage (P < 0.001), and treatment modality (P < 0.001) compared to those with intervals of > 2 years and without screening. Similar results were observed in those with < 3-year intervals. Conclusion Triennial endoscopic screening might be as effective as biennial screening in increasing the detection rate of EGC and the risk of subsequent curable endoscopic resections., Graphical Abstract

OBJECTIVE: The purpose of the present study was to determine the prognostic significance of the neutrophil-lymphocyte ratio (NLR) in recurrence of cervical intraepithelial neoplasia (CIN). METHODS: We evaluated the NLR as a prognostic marker in the entire cohort of 230 patients who had undergone surgical resection and were diagnosed with CIN. Subjects were categorized into two different groups based on the NLR (NLR-high and NLR-low) using cutoff values determined by receiver operating characteristic (ROC) analysis. The primary research objective for this study was to validate the impact of the NLR on recurrence-free survival (RFS) in patients with CIN. The secondary objective was to evaluate the impact of other hematologic parameters on RFS in CIN patients. RESULTS: Using the entire cohort, the most appropriate NLR cut-off value for CIN recurrence selected on the ROC curve was 2.1. The NLR-low and NLR-high groups included 167 (72.6%) and 63 patients (27.4%), respectively. According to Kaplan-Meier analysis, RFS rates during the entire follow-up period were considerably lower in the NLR-high group than in the NLR-low group (P = 0.0125). In multivariate survival analysis using Cox proportional hazard model, we identified the NLR, absolute eosinophil count (AEC), hemoglobin concentration, and mean corpuscular volume (MCV) as valuable prognostic factors that impact RFS. CONCLUSIONS: The NLR is an independent prognosticator for RFS following surgical resection in CIN patients. We also found that the AEC, hemoglobin level, and MCV were strongly associated with RFS, as determined by multivariate analysis using a Cox model. These hematological parameters might provide additional prognostic value beyond that offered by standard clinicopathologic parameters.

Objective Cancer stem cells (CSCs) represent a subpopulation of undifferentiated tumorigenic cells thought to be responsible for tumor initiation, maintenance, drug resistance, and metastasis. The role of CSCs in drug resistance and relapse of cancers could significantly affect outcomes of ovarian cancer patient. Therefore, therapies that target CSCs could be a promising approach for ovarian cancer treatment. The antibiotic salinomycin has recently been shown to deplete CSCs. In this study, we evaluated the effect of salinomycin on ovarian cancer stem cells (OCSCs), both alone and in combination with paclitaxel (PTX). Methods The CD44⁺CD117⁺CSCs were obtained from the ascitic fluid of patients with epithelial ovarian cancer by using an immune magnetic-activated cell sorting system. OCSCs were treated with PTX and salinomycin either singly or in combination. Cell viability and apoptosis assays were performed and spheroid-forming ability was measured. The expression of sex determining region Y-box 2 (SOX2) and octamer-binding transcription factor 3/4 (OCT3/4) mRNA was determined using reverse transcription polymerase chain reaction, and protein expression was observed using western blot analysis. Results Treatment with salinomycin alone reduced the stemness marker expression and spheroid-forming ability of OCSCs. Treatment with PTX alone did not decrease the viability of OCSCs. Treatment with a combination of salinomycin decreased the viability of OCSCs and promoted cell apoptosis. The enhancement of combination treatment was achieved through the apoptosis as determined by annexin V/propidium iodide (PI) staining, caspase-3 activity, and DNA fragmentation assay. Conclusion Based on our findings, combining salinomycin with other anti-cancer therapeutic agents holds promise as an ovarian cancer treatment approach that can target OCSCs.

After human papillomavirus (HPV) vaccine guidelines published by Korean Society of Gynecologic Oncology (KSGO) in 2011, new studies have been published, leading to additional data regarding efficacy, safety, number of vaccination rounds, and ideal age of vaccine administration. We searched and reviewed the literatures focused on the efficacy of 2-dose schedule vaccination, the efficacy of 3-dose schedule vaccination in middle-aged women, the ideal age of 3-dose schedule vaccination, the safety of HPV preventive vaccine, and the ability of cross-protection of each HPV preventive vaccine. The KSGO has revised the previous guideline based on the results of the above studies.

Resistance degradation of Ca-doped BaTiO3 ceramics was investigated. A series of coarse and fine-grained (Ba1–xCax)TiO3 with only Ba site incorporation ranging x from 0 to 0.1, and Ba(Ti1–yCay)O3 ceramics with only Ti site incorporation ranging y from 0 to 0.015, were prepared with similar grain sizes. The increase of x did not cause any distinct difference in degradation, whereas an increase in y caused a significant resistance degradation in both coarse and fine-grained specimens. The variation of ionic transference number (tion) as evaluated by the Warburg impedance was negligible with increase in x, but significantly increased with the increase in y. These results demonstrate that the decrease of lattice parameters and lattice shrinkage by the Ba site incorporation of Ca has little influence on the resistance degradation, and that the oxygen vacancy concentration generated by the Ti site incorporation of acceptor Ca is a very important factor that governs resistance degradation.

We have investigated the effects of BRCA1 over-expression and knockdown on 5F-203-induced gene expression and cytotoxicity in human breast cancer cells. 5F-203 is a chemotherapeutic prodrug that both induces a p450 enzyme, CYP1A1, and is metabolically activated by CYP1A1.We used several molecular biological techniques to confirm our findings. BRCA1 regulates sensitivity to 5F-203 by regulating the expression of CYP1A1 mRNA and its EROD activity. XRE-Luc reporter assays, semi-quantitative RT-PCR, Western blot analysis, EROD activity measurements, gene knockdown and MTT cell survival assays were used for this study.Our results show that the ability of 5F-203 treatments to increase CYP1A1 mRNA level and CYP1A1 enzymatic activity (EROD activity) are affected by BRCA1 protein levels. In addition, the ability of 5F-203 treatments to induce proteins, P53 and P53 target genes such as P21, is significantly decreased in BRCA1 knockdown cells, suggesting that BRCA1-related effects could at least partially explain why BRCA1 knockdown increases resistance to 5F-203-mediated cytotoxicity. We also observed altered expression of the two major transcription factors (AhR and ARNT) that affect CYP1A1 expression when BRCA1 protein levels are altered.BRCA1 is an important protein, which affects 5F-203-mediated cytotoxicity. Our findings are potentially clinically significant; they suggest that those patients most likely to respond to this new prodrug will have tumors containing normal amounts of BRCA1.

Chemo-resistance to cisplatin-centered cancer therapy is a major obstacle to effective disease treatment. Recently, salinomycin was proven to be highly-effective for the elimination of cancer stem cells both in vitro and in vivo. The objective of the present study was to evaluate the anticancer properties of salinomycin in cisplatin-resistant ovarian cancer cells (A2780cis).The tetrazolium dye (MTT) assay was used to determine cell viability. Flow cytometric analysis was performed to analyze the effect on cell cycle and apoptosis. The expression of apoptosis-related proteins was evaluated by western blot analysis.Cell viability was significantly reduced by salinomycin treatment in a dose-dependent manner. Flow cytometry showed an increase in sub-G1 phase cells. Salinomycin increased the expression of death receptor-5 (DR5), caspase-8 and Fas-associated protein with death domain (FADD). A decline in the expression of FLICE-like inhibitory protein (FLIP), activation of caspase-3 and increased poly ADP-ribose polymerase (PARP) cleavage, triggered apoptosis. Furthermore, annexin-V staining also revealed the apoptotic induction.These findings provide important insights regarding the activation of caspase-8 and DR5, to our knowledge, for the first time in salinomycin-treated cisplatin-resistant ovarian cancer and demonstrate that salinomycin could be a prominent anticancer agent.

Correspondence to Eon Jeong Nam, M.D. Department of Internal Medicine, Kyungpook National University School of Medicine, 130 Dongdeok-ro, Jung-gu, Daegu 700-721, Korea Tel: +82-53-420-5493, Fax: +82-53-426-2046, E-mail: ejnam@knu.ac.kr Copyrightc 2015 The Korean Association of Internal Medicine This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited. 비후성 뇌수막염과 대동맥주위염으로 발현한 IgG4 연관 질환 1예

Secondary tricuspid regurgitation (TR) primarily develops due to left heart failure or primary pulmonary diseases. Tricuspid annular dilation, which is commonly caused by right ventricular volume and pressure overload followed by right ventricle dilation, is believed to be the main mechanism underlying secondary TR. It is reported that once the tricuspid annulus is dilated, its size cannot spontaneously return to normal, and it may continue to dilate. These reports also suggest the use of an aggressive surgical approach for secondary TR. In the present report, we describe a case of tachycardia-induced severe TR that was completely resolved without the need for surgery.

Purpose To investigate the prognostic factors and effectiveness of postoperative radiotherapy alone for endometrial carcinoma. Materials and Methods Sixty four patients with stage I-III endometrial cancer (EC) treated with postoperative radiotherapy alone between January 1989 and December 2008 at the Keimyung University Dongsan Medical Center were chosen for the present study. Typically, total hysterectomy, salpingo-oophorectomy and lymphadenectomy were performed on the patient's pelvis. Total dose from 50.4 Gy to 63 Gy was irradiated at pelvis or extended field. Thirteen patients were treated with Co-60 or Ir-192 intracavitary radiotherapy. Follow-up periods were from 7 to 270 months, with a median of 56 months. Results Five year overall survival (OS) rate was 58.7%, respectively. Five year disease-free survival (DFS) rate was 59.2%, respectively. In univariate analysis for OS and DFS, stage, menopausal age, type of operation, serosal invasion, and lymph node involvement were found to be statistically significant. Histologic type was marginally significant. In multivariate analysis for OS and DFS, stage, types of operation, histologic type were also found to be statistically significant. Treatment failure occurred in 14 patients. The main pattern of failure was found to be distant metastasis. Time to distant metastasis was from 3 to 86 months (median, 12 months). There were no grade 3 or 4 complications. Conclusion Stage, types of operation, and histologic type could be the predictive prognostic factors in patients. We contemplated postoperative radiation as effective and safe treatment method for EC. Additional treatment would be needed to reduce distant metastasis.

Dielectric relaxation behavior of acceptor (Mg)-doped BaTiO3 ceramics was investigated with the increase of Mg concentration up to 0.6 mol. % in the temperature rang of 120 ∼ 540 °C. In the high temperature range above 320 °C, the activation energies of dielectric relaxation (Eτ) showed nearly similar values of ∼ 1.2 eV irrespective of Mg concentration. However, in the low temperature range below 320 °C, they continuously decreased from ∼ 1.2 eV and then saturated to ∼ 0.4 eV with the increase of Mg concentration. The activation energies of electrical conduction (Eσ) of the bulk grain evaluated by impedance analysis also showed almost the same behavior. Such coincidence demonstrates that the observed dielectric behaviors are caused by the space charge polarization at grain boundaries by conducting charge carriers. The disappearance of the dielectric relaxation in submicrometer fine-grain specimen also supports this mechanism. The variation of Eτ and Eσ with the increase of Mg concentration in the low temp...

Objective: This clinical study was to evaluate the patients' clinical and pathological characteristics and treatment results in women with ovarian granulosa cell tumor. Methods: A clinical study was made on 31 cases of ovarian granulosa cell tumor that were treated at the department of Obstetrics and Gynecology in the Keimyung University Dongsan Medical Center between January 1997 and December 2005. Clinical and pathological characteristics, treatment results, follow-up data for 31 women with granulosa cell tumor were collected retrospectively from medical records. Results: The mean age of patients was 49 years (24 to 86 years). The chief complaints of patients were 18 cases of abdominal mass, 3 cases of abdominal discomfort, 3 cases of vaginal bleeding, 1 case of hemoperitoneum and 3 cases of no symptom. Bilaterality of mass was 2 cases, and mean size of tumor was 8.7 cm. 64.5% of patients were with FIGO stage I, 6.4% with stage II, 16.1% with stage III, and none with stage IV. Follow-up time was 5 years. The five year disease free survival rate was 93%. Significant prognostic factors were FIGO stage. Conclusion: Even through granulosa cell tumor usually has good prognosis, it is a tumor of unquestionable malignant potential and has a tendency for late relapse. Long term follow-up is recommended.