• Title/Summary/Keyword: material evaluation

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Relationship between Quality of Frozen Surimi and Jelly Strength of Kamaboko (동결 surimi의 품질과 어묵 젤리 강도의 관계)

  • KIM Yuck-Yong;CHO Young-Je
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.25 no.2
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    • pp.73-78
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    • 1992
  • To investigate the desirable index for evaluation of frozen surimi's grades, the relationship between indices for grading of surimi, such as ATPase activity $(Ca^{2+}-,\;Mg^{2+}-\;and\;EDTA-)4, solubility, viscosity and K-value of frozen surimi and jelly strength of kamaboko was studied. The myofibrillar $Ca^{2+}-ATPase$ activity and solubility from frozen surimi of grades SA, FA, A, RA and B gave values of $1.184\pm0.2,\;0.956\pm0.14,\;0.766\pm/0.07,\;0.453\pm0.07\;and\;0.227\pm0.08$(umoles Pi/min/mg) for $Ca^{2+}-$ATPase activity and $93.19\pm5,\;84.62\pm4,\;70.63\pm5,\;41.21\pm4\;and\;32.82\pm4(\%)$ for solubility, respectively. Therefore, the myofibrillar $Ca^{2+}-$ATPase activity and solubility of surimi were closely related to the jelly strength of kamaboko from same material, as the correlation coefficient were 0.9584 and 0.9849, respectively. K-value, the index of freshness, was related to the jelly strength of frozen surimi as the correlation coefficient 0.9053 and shown as SA $15.67\pm1.4,\;FA\;14.94\pm 3,\;A\;28.00\pm5,\;RA\;32.16\pm3\;and \;B\;48.68\pm 5(\%)$. $Mg^{2+}-$ and EDTA-ATPase activity and viscosity were not related to the jelly strength. The $Ca^{2+}-$ATPase activity and solubility were found to be useful index for evaluating the quality of frozen surimi.

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Return to Sports Activity After Anterior Cruciate Ligament Reconstruction (전방십자인대 재건술 후 스포츠 활동 복귀)

  • Park, Jong-Hyuk;Lee, Jun-Mo;Bae, Hyun-Kyung;Im, Jong-Han;Lee, Ju-Hong
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.8 no.2
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    • pp.95-101
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    • 2009
  • Purpose: The purpose of this study was to determine how many of our patients who had had anterior cruciate ligament (ACL) reconstruction returned to their previous levels of sports and to identify why not doing so. Material and Methods: We evaluated 43 knees with a minimum of two years follow-up among whom undergoing 109 ACL reconstruction from September 2003. The mean age of patients was 26 years (17 to 45 years) Clinical results was evaluated according to the Lysholm Knee scores, Tegner activity score, subjective IKDC questionnaires, objective IKDC evaluation form and KT-1000 arthrometer. Results: The overall clinical results demonstrated significant improvement at the final follow-up comparing to preoperative data (P<0.05). Among 43 patients, 25 patients (58%) returned to their previous level of sports and 18 patients (42%) did not. Of whom, 11 patients (61%) were not able to return to sports due to fear to re-injury and 7 patients (39%) suffered from instability and pain. The differences in the Lysholm Scores, KT-1000 arthrometer and subjective IKDC in the 3 groups of patients by ANOVA test were found to be statistically significant (P<0.001). Although there is no difference in objective IKDC and KT-1000 arthrometer, the difference was observed in Tegner activities, subjective IKDC obtained by those who returned to sport and those who had fear to reinjury (P<0.001). Conclusion: This study showed that a quater of patients could not return to their previous level of sport after ACL reconstruction because of fear to reinjury. We thought that not only improving the technique of ACL reconstruction and systemic rehabilitation but also considering psychological factor of patients could allow more patients to return to the previous level of sports.

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Production of Alternative Coagulant Using Waste Activated Alumina and Evaluation of Coagulation Activity (폐촉매 부산물로부터 대체 응집제 제조 및 응집성능 평가)

  • Lee, Sangwon;Moon, Taesup;Kim, Hyosoo;Choi, Myungwon;Lee, Deasun;Park, Sangtae;Kim, Changwon
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.7
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    • pp.514-520
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    • 2014
  • In this study, the production potential of alternative coagulant ($Al_2(SO_4)_3$ solution) having the identical coagulation activity with respect to the commercial coagulant was investigated. The raw material of alternative coagulant was a spent catalyst including aluminium (waste activated alumina) generated in the manufacturing process of the polymer. The alternative coagulant was produced through a series of processes: 1) intense heat and grinding, 2) chemical polymerization and substitution with $H_2SO_4$ solution, 3) dissolution and dilution and 4) settling and separation. To determine the optimal operating conditions in the lab-scale autoclave and dissolver, the content of $Al_2O_3$ in alternative coagulant was analyzed according to changes of the purity of sulfuric acid, reaction temperature, injection ratio of sulfuric acid and water in the dissolver. The results showed that the alternative coagulant having the $Al_2O_3$ content of 7~8% was produced under the optimal conditions such as $H_2SO_4$ purity of 50%, reaction temperature of $120^{\circ}C$, injection ratio of $H_2SO_4$ of 5 times and injection ratio of water of 2.3 times in dissolver. In order to evaluate the coagulation activity of the alternative coagulant, the Jar-test was conducted to the effluent in aerobic reactor. As a result, in both cases of Al/P mole of 1.5 and 2.0, the coagulation activity of the alternative coagulant was higher than that of the existing commercial coagulant. When the production costs were compared between the alternative and commercial coagulant through economic analysis, the production cost reduction of about 50% was available in the case of the alternative coagulant. In addition, it was identified that the alternative coagulant could be applied at field wastewater treatment plant without environmental problem through ecological toxicity testing.

Evaluation of the radiopacity and cytotoxicity of resinous root canal sealers (레진계 근관충전실러의 방사선 불투과성 및 세포 독성에 대한 평가)

  • Kim, Chang-Kyu;Ryu, Hyun-Wook;Chang, Hoon-Sang;Lee, Byung-Do;Min, Kyung-San;Hong, Chan-Ui
    • Restorative Dentistry and Endodontics
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    • v.32 no.5
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    • pp.419-425
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    • 2007
  • The aim of this study was to evaluate the radiopacity and cytotoxicity of three resin-based (AH 26, EZ fill and AD Seal), a zinc oxide-eugenol-based (ZOB Seal), and a calcium hydroxide-based (Sealapex) root canal sealers. Specimens, 10 mm in diameter and 1 mm in thickness, were radiographed simultaneously with an aluminum step wedge using occlusal films, according to ISO 6876/2001 standards. Radiographs were digitized, and the radiopacity of sealers was compared to the different thicknesses of the aluminum step wedge, using the Scion image software. Using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, the cytotoxicity of each material was determined in immortalized human periodontal ligament (IPDL) cells. The results demonstrated that EZ fill was the most radiopaque sealer, while Sealapex was the least radiopaque (p < 0.05). AH 26, AD Seal and ZOB Seal presented intermediate radiopacity values. All the materials evaluated, except for Sealapex, presented the minimum radiopacity required by ISO standards. The cell viabilities of resin-based root canal sealers were statistically higher than that of other type of root canal sealers through the all experimental time. Further, EZ fill showed statistically lower cell viability in 24 and 48 hours compared to AD Seal and in 72 hours compared to all other resin-based root canal sealers. However, there was no correlation between the radiopacity and cytotoxicity of three resin-based root canals sealers (p > 0.05). These results indicate that resin-based root canal sealer is more biocompatible and has advantage in terms of radiopacity.

A Study on the Stability and Sludge Energy Efficiency Evaluation of Torrefied Wood Flour Natural Material Based Coagulant (반탄화목분 천연재료 혼합응집제의 안정성 및 슬러지 에너지화 가능성 평가에 관한 연구)

  • PARK, Hae Keum;KANG, Seog Goo
    • Journal of the Korean Wood Science and Technology
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    • v.48 no.3
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    • pp.271-282
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    • 2020
  • Sewage treatment plants are social infrastructure of cities. The sewage distribution rate in Korea is reaching 94% based on the sewage statistics based in the year of 2017. In Korean sewage treatment plants, use of PAC (Poly Aluminum Chloride) accounts for 58%. It contains a large amount of impurities (heavy metal) according to the quality standards, however, there have been insufficient efforts to reinforce the standards or technically improve the quality, which resulted in secondary pollution problems from injecting excessive coagulant. Also, the increase in the use of chemicals is leading to the increases in the annual amount of sewage sludge generated in 2017 and the need to reuse sludge. As such, this study aims to verify the possibility of reusing sludge by evaluating the stability of heavy metals based on the injection of coagulant mixture during water treatment which uses the torrefield wood powder and natural materials, and evaluating the sedimentation and heating value of sewage sludge. As a result of analyzing heavy metals (Cr, Fe, Zn, Cu, Cd, As, Pb, and Ni) from the coagulant mixture and PAC (10%), Cr, Cd, Pb, Ni, and Hg were not detected. As for Zn, while its concentration notified in the quality standards for drinking water is 3 mg/L, only a small amount of 0.007 mg/L was detected in the coagulant mixture. Maximum amounts of over double amounts of Fe, Cu, and As were found with PAC (10%) compared to the coagulant mixture. Also, an analysis of sludge sedimentation found that the coagulant mixture showed a better performance of up to double the speed of the conventional coagulant, PAC (10%). The dry-basis lower heating value of sewage sludge produced by injecting the coagulant mixture was 3,378 kcal/kg, while that of sewage sludge generated due to PAC (10%) was 3,171 kcal/kg; although both coagulants met the requirements to be used as auxiliary fuel at thermal power plants, the coagulant mixture developed in this study could secure heating values 200 kal/kg higher than the counterpart. Therefore, utilization of the coagulant mixture for water treatment rather than PAC (10%) is expected to be more environmentally stable and effective, as it helps generating sludge with better stability against heavy metals, having a faster sludge sedimentation, and higher heating value.

Anticoagulation Management after Mitral Valve Replacement with the St. Jude Medical Prosthesis (승모판치환 환자의 항응혈제 치료)

  • 김종환;김영태
    • Journal of Chest Surgery
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    • v.31 no.12
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    • pp.1172-1182
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    • 1998
  • Background: Primary goal of anticoagulation treatment in patients with mechanical heart valve is the effective prevention of thromboembolism and safe avoidance of bleeding as well. Material and Method: Two-hundred and nine patients with the St. Jude Medical prosthesis operated on between 1984 and 1995, for mitral(MVR 122), aortic(AVR 39) and double mitral and aortic valve replacement(DVR 48) respectively, were studied on the practically achieved levels of anticoagulation and the clinical outcomes. Patients were on Coumadin and followed up by monthly visit to outpatient clinic for examination and prothrombin time measurement to adjust the International Normalized Ratios(INRs) within the low-intensity target range between 1.5 and 2.5. Result: A total anticoagulation follow-up period was 1082.0 patient- years(mean 62.1 months) and INRs of 10,205 measurements were available for evaluation. The accomplished INRs among the replacement groups were not significantly different and only 65% of INRs were within the target range. And, in individual patients, only 37% of patients had INRs included within the target range in more than 70% of tests during follow-up period. The levels of INRs in patients with atrial fibrillation, which was found in 57% of patients, were definitely higher than the ones measured in patients with regular rhythm(p<0.001). Thromboembolisms were experienced by 15 patients with the incidence of 1.265%/patient- year(MVR 1.412%, AVR 0.462% and DVR 1.531%/patient-year) and major bleeding by 4 patients with the incidence of 0.337%/patient-year(MVR 0.424%, AVR none and DVR 0.383%/patient-year). Frequent as well as prolonged missing of prothrombin time tests was the main risk factor strongly associated with the thromboembolic complications(odds ratio 1.99). The proportion of INRs within target range of less than 60% in individual patient was the highly significant risk factor of both thromboembolic and overall embolic and bleeding complications(p<0.004 and p<0.002 respectively). Conclusion: In conclusion, the low-intensity therapeutic target range of INRs was adequate in patients with AVR and in sinus rhythm. However, the patients with replacement of the mitral valve were more likely to require higher target range of INRs, especially in the presence of atrial fibrillation, to achieve the practical levels of anticoagulation enough to prevent thromboembolic complications effectively. For the higher therapeutic target range of INRs between 2.0∼3.0, further accumulation of clinical evidences are required. It is highly desirable to improve the patients' compliance under continuous instructions in visiting outpatient clinic and in taking daily Coumadin without omission and to keep INRs consistently within optimal range with tight control for minimization of chances and of periods of exposure to the risk of complications. And, particularly, patients with high risk of complications and with wide fluctuation of INRs should be better managed with frequent monitoring anticoagulation levels.

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Active Prosthetic Valve Endocarditis: The Clinical Profile, Laboratory Findings and Mid-term Surgical Results (활동성 인공판막 심내막염: 임상 양상, 검사 소견 및 중기 수술 성적)

  • Kim, Hwan-Wook;Joo, Seok;Kim, Hee-Jung;Choo, Suk-Jung;Song, Hyun;Lee, Jae-Won;Chung, Cheol-Hyun
    • Journal of Chest Surgery
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    • v.42 no.4
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    • pp.447-455
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    • 2009
  • Background: Prosthetic valve endocarditis usually presents with clinical symptoms that are more severe than native valve endocarditis, and prosthetic valve endocarditis shows the spread of infection into the surrounding tissue as well as into the superficial endocardial layers. The postoperative prognosis is especially poor for valve re-replacement for the cases of active endocarditis that are unable to receive a full-course of pre-antibiotic therapy due to complications and the ensuing clinical aggravation. The aim of this study was to evaluate the clinical profiles, laboratory findings and mid-term surgical results of active prosthetic valve endocarditis. Material and Method: Among the 276 surgically treated infective endocarditis patients who were treated during the period from January 1998 to July 2008, 31 patients were treated for prosthetic valve endocarditis. Among these patients, 24 received surgical treatment for an 'active' state, and they were selected for evaluation. Result: The most frequently encountered symptom was a febrile sensation. Eight cases (33.3%) were accompanied by systemic thromboembolism, among which 5 cases (20.8%) had an affected central nervous system. 'Vegetations' were most commonly found on transesophageal echocardiography, and the 'Staphylococcus species' were the most frequent pathogens. There were 4 deaths in the immediate postoperative period, and an additional 4 patients died during the follow-up period (Mean$\pm$SD, 42.1$\pm$36.9 months). The cumulative survival rate was 79% at 1 year, 73% at 3 years, 66% at 5 year, and 49.5% at 7 years. Conclusion: The cases of active prosthetic valve endocarditis that were unable to receive a full course of preoperative antibiotics therapy generally have a poor prognosis. Nevertheless, early surgery and extensive resection of all the infected tissue is pivotal in improving the survival rate of patients with surgically treated active prosthetic valve endocarditis.

Substrate chain-length specificities of polyhydroxyalkanoate synthases PhaC1 and PhaC2 from Pseudomonas aeruginosa P-5 (Pseudomonas aeruginosa P-5에 존재하는 polyhydroxyalkanoate synthase PhaC1과 PhaC2의 기질특이성)

  • Woo, Sang Hee;Lee, Sun Hee;Rhee, Young Ha
    • Korean Journal of Microbiology
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    • v.52 no.4
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    • pp.455-462
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    • 2016
  • Pseudomonas aeruginosa P-5 is an unusual organism capable of synthesizing polyhydroxyalkanoates (PHAs) consisting of 3-hydroxyvalerate (3HV) and medium-chain-length (MCL) 3-hydroxyalkanoate (3HA) monomer units when C-odd alkanoic acids are fed as the sole carbon source. Evaluation of the substrate chain-length specificity of two P. aeruginosa P-5 PHA synthases ($PhaC1_{P-5}$ and $PhaC2_{P-5}$) by heterologous expression of $PhaC1_{P-5}$ and $PhaC2_{P-5}$ genes in Pseudomonas putida GPp104 revealed that $PhaC2_{P-5}$ incorporates both 3HV and MCL 3HAs into PHA, whereas $PhaC1_{P-5}$ favors only MCL 3HAs for polymerization. In order to obtain $PhaC2_{P-5}$ mutants with altered substrate specificity, site-specific mutagenesis for $PhaC2_{P-5}$ was conducted. Amino acid substitutions of $PhaC2_{P-5}$ at two positions (Ser326Thr and Gln482Lys) were very effective for synthesizing copolymers with a higher 3HV fraction. When recombinant P. putida GPp104 harboring double mutated $phaC2_{P-5}$ gene ($phaC2_{P-5}QKST$) was grown on nonanoic acid, 2.5-fold increase of copolymer content with 3.8-fold increase of 3HV fraction was observed. The $phaC2_{P-5}QKST$-containing Ralstonia eutropha PHB-4 supplemented with valeric acid also produced copolymers consisting of 3HV and 3-hydroxyheptanoate with a high 3HV fraction. These results suggest that recombinants containing $phaC2_{P-5}QKST$ could be useful for production of new PHA copolymers with improved material properties.

Analysis of Exploratory Thoracotomy in Non-Small Cell Lung Cancer (원발성 폐암에서의 시험적 개흉술의 분석)

  • 허재학;성숙환;김영태
    • Journal of Chest Surgery
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    • v.32 no.6
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    • pp.536-542
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    • 1999
  • Background: The purpose of this study is to improve the quality of the diagnostic procedures in the preoperative evaluation so as to reduce the unnecessary thoracotomy and to ensure resectability in non-small cell lung cancer. Material and Method: Of 616 patients who underwent thoracotomy for primary lung cancer from January 1990 to December 1996, 59 patients(9.6%) turned out to have inoperable lesions after the thoracotomy. We reprospectively reviewed the bronchoscopic findings, methods of tissue diagnosis, CT scans, pulmonary function test and lung perfusion scan, reasons for nonresectability, and adjuvant therapy, and then followed up on the survival rate after exploratory thoracotomy. Result: The cell types were squamous cell carcinoma in 38, adenocarcinoma in 15, large cell carcinoma in 3 and others in 3. Primary loci were RUL in 20, RML in 6, RLL in 8, LUL in 13, LLL in 4 and others in 8. The reasons for non-resectability were various; direct tumor invaison to mediastinal structures(n=41), seeding on pleural cavity(n=8), poor pulmonary function(n=2), invasions to extranodal mediastinal lymph node(n=2), technical non- resectability due to extensive chest wall invasion (n=3), small cell carcinoma (n=1), malignant lymphoma(n=1), and multiple rib metastases(n=1). In the follow-up of 58 patients, 1-year survival rate was 55.2% and 2-year survival rate was 17.2% and the mean survival time was 14 months. When compared according to cell types or postoperative adjuvant therapeutic modalities, no significant difference in the survival rates were found. The squamous cell carcinoma was frequently accompanied by local extension to contiguous structures and was the main cause of non-resectability. In adenocarcinoma, pleural seeding with malignant effusion was frequently encountered, and was the major reason for non-resectability. Conclusion: These data revealed that if appropriate preoperative diagnostic tools had been available, many unnecessary thoracotomies could have been avoided. Both the use of thoracoscopy in selected cases of adenocarcinoma and the more aggressive surgical approach to the locally advanced tumor could reduce the incidence of unnecessary thoracotomies for non-small cell lung cancers.

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The Sympathetic Skin Responses after Thoracic Sympathicotomy for Patients with Palmar Hyperhidrosis (수장부 다한증환자의 흉부 교감신경절단술후 교감신경 피부반응)

  • 김오곤;홍종면;이석재;홍장수;이광래;김상규
    • Journal of Chest Surgery
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    • v.32 no.6
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    • pp.579-583
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    • 1999
  • Background: Thoracic sympathicotomy has been used safely and successfully to manage palmar hyperhidrosis. The preoperative and postoperative recording of Sympathetic Skin Responses(SSR) was performed for objective evaluation and follow-up of thoracic sympathicotomy in hyperhidrosis patients, and also for ascertaining the clinical usefullness of SSR. Material and Method: The recording of SSR was performed on 15 patients suffering from palmar hyperhidrosis with Medelec Sapphire Plus electromyogragh before and after thoracic sympathicotomy. Eletrical stimuli on the right median nerve was made in patients in supine position and results were recorded on right and left palms with soles at the same time by 4 channels. Skin temperatures were also monitored simultaneously. T2,3 sympathicotomy was performed with VATS in every patients. SSR was done in 2 patients one month later. Result: Clinically, all patients had symptomatic improvement with satisfaction. Postoperative complication was small amount of residual pneumothorax in 5 patients but it was absorbed sponteneously. There was no recurrence during follow-up period and ten patients(66%) complained compensatory hyperhidrosis. After operation, SSR change was shown in every 15 patients. Abolition of SSR on both palms was achieved in 12 patients(80%) and on both soles in 6 patients. In the other 3 patients, the latencies were significantly delayed and the amplitudes were significantly reduced at both palms and soles. In two patients who were examined at one month later after operation, similar results with postoperative SSRs were shown. The skin temperature on preoperative both palm and sole were lower than normal temperature, and those on postoperative both palm and sole were increased. Those had statistical significance(p<0.05), and the temperature on the palm was increased higher that than on the sole. Conclusion: After thoracic sympathicotomy was performed on palmar hyperhidrosis patients, an increment of skin temperatures and SSR changes were achieved at both palms and soles of all patients. Palmar SSRs were completely abolished in 12 patients(80%), and similar results of postoperative SSRs were achieved. The recording of SSR may be useful to easily and objectively assess the completeness of sympathicotomy and the follow-up of recurrence in hyperhidrosis patients.

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