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A Study on Titanium Miniscrew as Orthodontic Anchorage : An experimental investigation in dogs (성견에서 교정적 고정원으로서의 티타늄 미니스크류에 대한 연구)

  • Yoon, Byung-Soo;Choi, Byung-Ho;Lee, Won-You;Kim, Kyoung-Nam;Shim, Hyung-Bo;Park, Jin-Hyung
    • The korean journal of orthodontics
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    • v.31 no.5 s.88
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    • pp.517-523
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    • 2001
  • Titanium miniscrews we being used increasingly as an anchorage for tooth movement, because they ate easy to place and to remove, increase the number of sites available, give minimum strain to patients regarding surgical procedures, and offer uneventful healing alter removal. The use of titanium miniscrews as an orthodontic anchorage has been reported in clinical case reports, but clinicians have experienced screw loosening when using such screws.' To our knowledge, there are no published reports evaluating the stability of miniscrews. Information about the length of miniscrews used in relation to the location is of some importance, as stability will vary depending on bone duality The purpose of this study was to evaluate a variety of Lengths of miniscrews (dimeter: 2mm) which were inserted in maxilla or mandible and to demonstrate in a dog model which miniscrew provides fundamental stability in the jaws. 10 mm long miniscrews in the maxilla and 8mm long: miniscrews in the mandible showed no clinical mobility and retained their position throughout an 8 weeks force (200g) application. The mucosal condition around the screws was healthy in cases in which miniserews were inserted in the alveolar bone between the roots and the head of the screws emerged into the attached gingiva. When the force application was terminated, radiographic analysis revealed neither rent resorption not periodontal pathology around the miniscrews that remained stable during the entire treatment period. This study suggests that if titanium miniscrews with adequate length are properly used depending on the location, they provide sufficient stability for orthodontic anchorage.

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Serum Tumor Marker Levels might have Little Significance in Evaluating Neoadjuvant Treatment Response in Locally Advanced Breast Cancer

  • Wang, Yu-Jie;Huang, Xiao-Yan;Mo, Miao;Li, Jian-Wei;Jia, Xiao-Qing;Shao, Zhi-Min;Shen, Zhen-Zhou;Wu, Jiong;Liu, Guang-Yu
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.11
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    • pp.4603-4608
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    • 2015
  • Background: To determine the potential value of serum tumor markers in predicting pCR (pathological complete response) during neoadjuvant chemotherapy. Materials and Methods: We retrospectively monitored the pro-, mid-, and post-neoadjuvant treatment serum tumor marker concentrations in patients with locally advanced breast cancer (stage II-III) who accepted pre-surgical chemotherapy or chemotherapy in combination with targeted therapy at Fudan University Shanghai Cancer Center between September 2011 and January 2014 and investigated the association of serum tumor marker levels with therapeutic effect. Core needle biopsy samples were assessed using immunohistochemistry (IHC) prior to neoadjuvant treatment to determine hormone receptor, human epidermal growth factor receptor 2(HER2), and proliferation index Ki67 values. In our study, therapeutic response was evaluated by pCR, defined as the disappearance of all invasive cancer cells from excised tissue (including primary lesion and axillary lymph nodes) after completion of chemotherapy. Analysis of variance of repeated measures and receiver operating characteristic (ROC) curves were employed for statistical analysis of the data. Results: A total of 348 patients were recruited in our study after excluding patients with incomplete clinical information. Of these, 106 patients were observed to have acquired pCR status after treatment completion, accounting for approximately 30.5% of study individuals. In addition, 147patients were determined to be Her-2 positive, among whom the pCR rate was 45.6% (69 patients). General linear model analysis (repeated measures analysis of variance) showed that the concentration of cancer antigen (CA) 15-3 increased after neoadjuvant chemotherapy in both pCR and non-pCR groups, and that there were significant differences between the two groups (P=0.008). The areas under the ROC curves (AUCs) of pre-, mid-, and post-treatment CA15-3 concentrations demonstrated low-level predictive value (AUC=0.594, 0.644, 0.621, respectively). No significant differences in carcinoembryonic antigen (CEA) or CA12-5 serum levels were observed between the pCR and non-pCR groups (P=0.196 and 0.693, respectively). No efficient AUC of CEA or CA12-5 concentrations were observed to predict patient response toward neoadjuvant treatment (both less than 0.7), nor were differences between the two groups observed at different time points. We then analyzed the Her-2 positive subset of our cohort. Significant differences in CEA concentrations were identified between the pCR and non-pCR groups (P=0.039), but not in CA15-3 or CA12-5 levels (p=0.092 and 0.89, respectively). None of the ROC curves showed underlying prognostic value, as the AUCs of these three markers were less than 0.7. The ROC-AUCs for the CA12-5 concentrations of inter-and post-neoadjuvant chemotherapy in the estrogen receptor negative HER2 positive subgroup were 0.735 and 0.767, respectively. However, the specificity and sensitivity values were at odds with each other which meant that improving either the sensitivity or specificity would impair the efficiency of the other. Conclusions: Serum tumor markers CA15-3, CA12-5, and CEA might have little clinical significance in predicting neoadjuvant treatment response in locally advanced breast cancer.

Spontaneous Resolution Rate and Predictive Factors of Resolution in Children with Primary Vesicoureteral Reflux (소아에서 일차성 방광요관역류의 자연소실율 및 관련 인자)

  • Kang, Eun-Young;Kim, Min-Sun;Kwon, Keun-Sang;Park, Eun-Hye;Lee, Dae-Yeol
    • Childhood Kidney Diseases
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    • v.11 no.1
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    • pp.74-82
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    • 2007
  • Purpose : To analyze the clinical characteristics, spontaneous resolution rate and predictive factors of resolution in children with primary vesicoureteral reflux(VUR). Methods : Between October 1991 and July 2003, 149 children diagnosed with primary VUR at Chonbuk National University Hospital were reviewed retrospectively. All of the patients were maintained on low-dose antibiotic prophylaxis and underwent radionuclide cystograms at 1 year intervals over 3 years after the initial diagnosis of VUR by voiding cystourethrogram was made. Results : The median time to resolution of VUR was 24 months and the total 3 year-cumulative resolution rate of VUR was 61.7%. The following variables were associated with resolution of VUR according to univariate analysis-; age<1 year, male gender, mild grade of reflux, unilateral reflux, congenital hydronephrosis as clinical presentation at time of diagnosis of VUR, absence of focal defects in the renal scan at diagnosis, absence of recurrent UTI, renal scars and small kidney during follow-up. After adjustment by Cox regression model, five variables remained as independent predictors of VUR resolution; age<1 yew, relative risk 1.77(P<0.05), VUR grade I+II 2.98(P<0.05), absence of renal scars 2.23(P<0.05), and absence of small kidney 5.20(P<0.01) during follow-up. Conclusion : In this study, spontaneous resolution rate of VUR, even high grade reflux, is high in infants during medical management, and it was related to age, reflux grade at diagnosis, absence of renal scars and small kidney during follow-up. Therefore early surgical intervention should be avoided and reserved for the selected groups.

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The Effect of Matrix Metalloproteinase Inhibitor for Left Ventricular Remodeling after Myocardial Infarction in a Rabbit Model (토끼에서 Myocardial Infarction 후 Left Ventricular Remodeling에 대한 Matrix Metalloproteinase의 차단 효과)

  • Kim, Soo-Hyun;Jung, Tae-Eun;Hong, Geu-Ru;Han, Sung-Sae
    • Journal of Chest Surgery
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    • v.40 no.5 s.274
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    • pp.329-340
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    • 2007
  • Background: Matrix Metalloproteinase (MMP) inhibition has emerged as a potential therapeutic strategy for the left ventricular dilatation that occurs after myocardial infarction. This study is designed to evaluate which treatment is better for attenuating the left ventricular remodeling via MMP inhibition 1) during the early, short highly MMP producing period of the initial phase or 2) during most of the period of the initial phase after myocardial infarction. Material and Method: Myocardial infarction was induced by ligation of the left anterior descending coronary artery in rabbits. The experimental group was divided into 3 groups. The myocardial infarction only (MI only) group consisted of 7 cases. The MMP inhibitor administered for 5 days after MI (MMPI 50) group had 6 cases, and these rabbits were given MMP inhibitor for 5 days after myocardial infarction, beginning with the postoperative first day. MMP inhibitor administered for 9 days (MMPI 90) group consisted of 5 cases and these rabbits were given MMPI for 9 days the same manner as above. CG2300 was used as a selective MMPI; this is a potent MMP-2 and -9 inhibitor Two-D echocardiograms were performed on all the groups at the time of preoperative period, the post-operative 1st week, the postoperative 20 week and the postoperative 30 week, and we measured the end-diastolic dimension (EDD), the end-systolic dimension (ESD), and the ejection fraction (EF). Result: The echocardiograms generally showed postoperative left ventricular dilatation in the MI only group. The EDD was increased significantly higher in the postoperative 1 week compared to the preoperative value (p<0.05). The ESD was also increased significantly higher in the postoperative 1st week, the postoperative 20 week and the postoperative 30 week compared to the preoperative value (p<0.05). Left ventricular dilatation was noted to be less In the MMPI 9d group than in the MI only and MMPI 5d groups. In the MMPI 9d group, there was no significant change of EF postoperatively compared to the preoperative period. MMP-2 and MMP-9 were measured from the infarcted myocardial tissue at post-MI 4 weeks by performing western blotting and zymography. The changes the of protein expression and activity of MMP-2 and MMP-9 were not significant in the three MI groups and the normal heart group. Histopathologic examination revealed severe collagen deposition in the MI only group. Collagen accumulation was reduced in both the MMPI groups. The MMPI 9d group revealed an increased number of capillaries. Conclusion: Left ventricular dilatation developed rapidly after, MI from ligation of the coronary artery and MMPI attenuated the ventricular dilatation. The effect of MMPI seemed to have better a result from its usage during most of the period of the initial phase after myocardial infarction. This suggested that increased neovascularization by MMPI may also contribute to attenuation of the left ventricular remodeling.

Result of Radiation Therapy of Cerebellar Medulloblastoma - with Emphasis on the Neuraxis Dose - (전중추신경계 조사선량을 중심으로 한 수아세포종의 방사선치료성적)

  • Kim Joo Young;Kim Il Han;Ha Sung Whan;Park Charn Il
    • Radiation Oncology Journal
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    • v.11 no.1
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    • pp.69-77
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    • 1993
  • Treatment of cerebellar medulloblastoma has been much improved with modern surgical technique for gross total tumor removal and adequate radiation therapy for the whole craniospinal axis. Questions have been arosen about the optimal radiation dose for the preventive treatment of whole cranium and whole spinal axis. Recently, many authors have reported their treatment results as comparable to older data, using lower than conventional dose of 3,600 cGy-4,000 cGy. For 50 patients treated between 1981 and 1990 at the Department of Radiation Therapy of SNUH, retrospective analysis was done for the treatment result, especially the neuraxis control, by radiation dose for the presymptomatic area of the disease. Analysis only by total spinal dose did not give any significant difference. But further analysis by following patient group; 3,600 cGy/150 cGy (n=6), 3,000 cGy/150 cGy (n=10), 2,400 cGy/150 cGy (n=17) and 2,400 cGy/100-120 cGy (n=11) showed significant improvement of neuraxis control by decreasing order (p =0.003). There was no significant difference in overall survival between the groups. For the 19 patients who had been confirmed initially as having no neuraxis disease, TDF 30 was the cur-off value that could prevent neuraxis failure (p =0.004). We couldn't define any TDF value that give reasonable control for the patient group with positive CSF study at initial diagnosis.

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In Vitro Intrinsic Radiosensitivity Of Human Squamous Cell Carcinoma in Primary Culture (인체 상피 세포암의 일차 배양을 이용한 방사선 민감도 측정)

  • Choi Eun Kyung;Yang Kwang Mo;Yi Byong Yong;Chang Hyesook;Kim Sang-Yoon;Nam Joo-Hyun;Yu Eunsil;Lee Inchul
    • Radiation Oncology Journal
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    • v.12 no.1
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    • pp.27-31
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    • 1994
  • There are a number of reports suggesting that there may be a correlation between the clinical response to radiotherapy in various tumors and the clonogenic survival of cell lines derived from these tumors following exposure to 2 Gy(SF2). Authors conducted this study to determine SF2 for cells in primary culture from surgical specimens. The tumor tissues with squamous cell carcinoma of uterine cervix and head and neck were obtained. The tumor tissues were disaggregated to single cells by incubating with collagenase type w for 2 hours with constant stirring. Single cell suspensions were inoculated in four 24-well plates precoated with cell adhesive matrix. After 24 hours of incubation at 37$ ^{\circ}C $, rows of four wells were then irradiated, consisting of control set and five other sets each receiving doses of 1,2,3,4, and 6 Gy. After incubation for a total of 13 days, the cultures were stained with crystal violet and survival at each dose was determined by quantitative image analysis system, To determine whether cell growth was of epithelial origin, immunocytochemical staining with a mixture of cytokeratin and epithelial monoclonal antibodies were performed on cell cultures. During the period of this study, we received 5 squamous cell carcinoma specimens of head and neck and 20 of uterine cervical carcinoma. Of these, 15 yielded enough cells for radiosensitivity testing. This resulted an overall success rate of 60$ \% $. The mean SF2 value for 15 tumours was 0.55$\pm$0.17 ranging from 0.20 to 0.79. These results indicate that there is a broad range of sensitivities to radiation in same histologic type. So with a large patient population, we plan to determine whether a different SF2 value is associated with tumours that are controlled with radiotherapy than those that are not.

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Antiangiogenic Effect of $As_4O_6$ on the Angiogenesis Induced by Vascular Endothelial Growth Factor (VEGF) in the Rat Cornea (랫드 각막에서 Vascular Endothelial Growth Factor(VEGF)로 유발시킨 신생혈관에 대한 $As_4O_6$의 혈관신생 억제효과)

  • Kwon Do-hyoung;Jang Jae young;Yi Na-young;Jeong Man-bok;Park Shin-ae;Kim Min-su;Nam Tchi-chou;Park Myung-jin;Bae Ill-ju;Rhee Chang-hun;Seo Kang-moon
    • Journal of Veterinary Clinics
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    • v.22 no.1
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    • pp.16-20
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    • 2005
  • The purpose of this study was to compare the antiangiogenic effects of As₄O/sub 6/ to those of As₂O₃ on the rat corneal micropocket model induced by VEGF. 20 ng VEGF impregnated pellets were used for angiogenic inducer on the rat cornea micropocket assay in this study. After ophthalmoscopic examination, Sprague-Dawley rats with normal cornea were implanted VEGF pellet. Total 60 eyes were used in this study. Control group only received VEGF pellet, As₂O₃ group followed oral administration of As₂O₃ at a dose of 50 mg/kg per day after VEGF pellet implantation and As₄O/sub 6/ group followed oral administration of As₄O/sub 6/ at a dose of 50 mg/kg per day after VEGF pellet implantation were classified. The eyes were examined under a surgical microscope daily on postoperative from day 3 to day 9 after pellet implantation. The number, length, clock hour of vascularization, and area of vessels in As₄O/sub 6/ group were significantly less evident than those of control group and As₂O₃ group (P < 0.05). In conclusion, As₄O/sub 6/ had better antiangiogenic effects on the new vessel induced by VEGF in the rat cornea.

Proteinases and their Inhibitors in Cartilage and Synovial Fluid Acquired from a Canine Osteoarthritic Model (개 퇴행성 관절염 모델을 이용한 연골과 활액 내 단백질 분해 효소와 억제제의 작용 연구)

  • Seo, Jae-Won;Lee, Hae-Beom;Kim, Nam-Soo;Lee, Young-Hoon;Kang, Hyung-Sub;Kim, In-Shik;Park, Sang-Youel
    • Journal of Veterinary Clinics
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    • v.26 no.2
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    • pp.144-149
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    • 2009
  • Chondrocytes and synovial fluid derived markers are used to monitor for osteoarthritis(OA). Specific inhibitors, known as tissue inhibitors of metalloproteinases(TIMP), regulate the proteolytic activity of matrix metalloproteinases(MMP). This study investigated whether MMP and TIMP levels were altered in synovial fluid and cartilage following the experimental induction of OA in canines. Twenty mature beagle dogs underwent a unilateral surgical transection of the cranial cruciate ligament and the medial collateral ligament as well as a medial meniscectomy. Matrix metalloproteinase-2 and MMP-9 levels were assayed using Western blot and TIMP-2 levels were measured with enzyme-linked immunosorbent assays four weeks after OA induction. Increased MMP-2 expression was observed in chondrocytes isolated from cartilage following OA induction, but MMP-9 expression decreased. Matrix metalloproteinase-2 and MMP-9 levels in synovial fluid from the OA induced joint significantly increased compared to those of the sham group. Tissue inhibitors of metalloproteinase-2 concentrations were higher in chondrocytes from the OA cartilage, yet TIMP-2 remained lower in the synovial fluid of OA. This suggests the elevated release of MMP-9 over MMP-2 into the synovial fluid following the cartilage degradation-related death of chondrocytes after OA. Osteoarthritis can be further deteriorated by increased MMP activity in the synovial fluid because TIMP-2 exist low concentration into the extracellular matrix. As a result, MMP activity, particularly MMP-9 activity, can be useful as a biomarker in diagnosing and monitoring the early stages of canine OA.

Enact of Ischemic Preconditioning on Myocardial Protection A Comparative Study between Normothermic and Moderate Hypothermic Ischemic Hearts Induced by Cardioplegia in Rats - (허혈 전처치가 심근보호에 미치는 영향 -적출 쥐 심장에서 상온에서의 심근허혈과 중등도 제체온하에서 심근정지액 사용 시의 비교 연구-)

  • 조성준;황재준;김학제
    • Journal of Chest Surgery
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    • v.36 no.4
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    • pp.242-254
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    • 2003
  • Most of the studies conducted have investigated the beneficial effects of ischemic preconditioning on normothermic myocardial ischemia. However, the effect of preconditioning could be attenuated through the use of multidose cold cardioplegia as practiced in contemporary clinical heart surgical procedures. The purpose of this study was to investigate whether preconditioning improves postischemic cardiac function in a model of 25℃ moderate hypothermic ischemic heart induced by cold cardioplegia in isolated rat hearts. Material and Method: The isolated Sprague-Dawley rat hearts were randomly assigned to four groups. All hearts were perfused at 37℃ for 20 minutes with Krebs-Henseleit solution before the baseline hemodynamic data were obtained. Group 1 consisted of preconditioned hearts that received 3 minutes of global ischemic preconditioning at 37℃, followed by 5 minutes of reperfusion before 120 minutes of cardioplegic arrest (n=6). Cold (4℃) St. Thomas Hospital cardioplegia solution was infused to induce cardioplegic arrest. Maintaining the heart at 25℃, infusion of the cardioplegia solution was repeated every 20 minutes throughout the 120 minutes of ischemic period. Group 2 consisted of control hearts that underwent no manipulations between the periods of equilibrium and 120 minutes of cardioplegic arrest (n=6). After 2 hours of cardioplegic arrest, Krebs solution was infused and hemodynamic data were obtained for 30 minutes (group 1, 2: cold cardioplegia group). Group 3 received two episodes of ischemic preconditioning before 30 min of 37℃ normothermic ischemia and 30 minutes of reperfusion (n=6). Group 4 served as ischemic controls for group 3 (group 3, 4: warm ischemia group). Result: Preconditioning did not influence parameters such as left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), rate-pressure product (RPP) and left ventricular dp/dt (LV dp/dt) in the cold cardioplegia group. (p=NS) However, preconditioning before warm ischemia attenuated the ischemia induced cardiac dysfunction, improving the LVSP, LVEDP, RPP, and LVdp/dt. Less leakage of CPK and LDH were observed in the ischemic preconditioning group compared to the control group (p<0.05). Conclusion: Ischemic preconditioning improved postischemic cardiac function after warm ischemia, but did not protect cold cardioplegic hearts.

The Role of External Irradiation for the Locally Advanced Papillary Thyroid Cancers (국소적으로 진행된 갑상선 유두암에서의 방사선치료의 역할)

  • Kim Tae-Hyun;Yang Dae-Sik;Kim Chul-Yong;Choi Myung-Sun
    • 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).

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