In the framework of the finite element method (FEM), a prediction method for the heating rate and the skin friction on a body surface is presented by using the energy and momentum conservation equations respectively. ...In the framework of the finite element method (FEM), a prediction method for the heating rate and the skin friction on a body surface is presented by using the energy and momentum conservation equations respectively. Meanwhile, a brief analysis is made of the role the weighted functions play in the present work.展开更多
Total skin electron therapy (TSET) is used for the treatment of Mycosis Fungoides. Several tech-niques have been developed, in order to achieve homogeneous dose distribution over the complete body surface. To implemen...Total skin electron therapy (TSET) is used for the treatment of Mycosis Fungoides. Several tech-niques have been developed, in order to achieve homogeneous dose distribution over the complete body surface. To implement a TSET technique, one has to optimize a variety of parameters. Monte Carlo simulation of TSET can facilitate this optimization. The aim of this study was to commission and optimize a TSET technique using the 4 and 6 MeV electron and the high dose rate facility on the Elekta Precise accelerator. The EGS4nrc/BEAMnrc Monte Carlo code was used. The beam data were calculated and measured at two different scoring planes for a single beam. The Model was validated by comparing the simulation with measurements. Two different vertical angles were used to obtain a uniform dose. The angle was optimized for best dose uniformity. The Rando phantom is placed on a rotating platform and rotates 60 degrees apart to facilitate the six patient position orientations. The doses delivered in a phantom by complete treatment were measured with Kodak EDR2 films and TLDs. The dose distribution varied among various scanning directions by 2 - 3 mm and 3 - 4 mm for 4 and 6 MeV respectively. The composite percentage depth dose of all six dual fields for the 4 and 6 MeV yielded an R80 of ~4 mm and ~6 mm, respectively. Dose uniformity was ±6% for 4 MeV and ±5% for 6 MeV. The bremsstrahlung contamination was 0.9% - 1.3%. Good agreements were found with published literature and inline with international protocols.展开更多
Pain sensation may appear under long-lasting mechanical stimulation. Although people have the experience that pain sensation generally decreases with time while the stimulation remains, the underlying mechanism remain...Pain sensation may appear under long-lasting mechanical stimulation. Although people have the experience that pain sensation generally decreases with time while the stimulation remains, the underlying mechanism remains elusive. We experimentally studied the thermal and strain rate- dependent viscoelastic behavior of skin in uniaxial stretch and numerically investigated the effects of temperature and strain rate on pain sensation. The results indicate that the viscosity of skin tissue decreases with increasing temperature and reducing strain rate, which subsequently decreases the discharge frequency of skin nociceptor and thus relieves the pain sensation. The results would contribute to the understanding of pain relief mechanism and optimizing for mechanical treatment.展开更多
目的应用心率变异性(heart rate variability,HRV)及皮肤交感神经活性(skin sympathetic nerve activity,SKNA)的方法,探讨持续非卧床腹膜透析(continuous ambulatory peritoneal dialysis,CAPD)与维持性血液透析(maintenance hemodialy...目的应用心率变异性(heart rate variability,HRV)及皮肤交感神经活性(skin sympathetic nerve activity,SKNA)的方法,探讨持续非卧床腹膜透析(continuous ambulatory peritoneal dialysis,CAPD)与维持性血液透析(maintenance hemodialysis,MHD)患者在单次透析过程中自主神经张力变化及差异。方法纳入2021年2月─7月在南京医科大学第一附属医院肾科住院的CAPD患者及血液透析中心MHD患者,自透析开始(MHD患者自48h间隔后上机,CAPD患者晨起时更换夜间留腹透析液)采集4 h连续高频心电信号,依据透析方式不同分为CAPD组及MHD组,并比较2组患者透析中每30 min平均心率、全部正常窦性心搏间期的标准差(standard deviation of the interbeat interval of normal sinus beats,SDNN)、标准化低频功率(normalized low frequency power,LFn)、标准化高频功率(normalized high frequency power,HFn)、低频高频功率比值(LF/HF)及SKNA平均电压(average voltage of SKNA,aSKNA)的变化及组间差异。结果共纳入30例CAPD及50例MHD患者。2组患者第1、2个30 min的平均心率(t=-2.210、-2.426,P=0.037,0.018)及HFn(Z=2.226、2.027,P=0.026、0.043)有统计学差异,第2个30 min的LFn有统计学差异(t=-2.548,P=0.013)。透析后,2组患者均表现出LF/HF升高(Z=3.162,2.980,P=0.011,0.020),MHD组变化更早;MHD组平均心率增加(q=3.336,P=0.009),HFn降低(Z=4.123,P<0.001)。各时段aSKNA 2组相比无统计学差异(0.010<|Z|<1.109,均P>0.05),但MHD组动态变化更大(Z>3.125,P<0.05)。结论MHD患者较CAPD患者在单次透析中自主神经指标变化更大。展开更多
目的探讨菱形皮瓣成形术在烧伤后瘢痕挛缩中的应用效果。方法选取2018年10月至2023年10月徐州医科大学附属淮海医院收治的98例烧伤后瘢痕挛缩患者进行回顾性分析,所有患者均采取皮瓣修复治疗,游离皮瓣组49例患者采取常规游离皮瓣移植术...目的探讨菱形皮瓣成形术在烧伤后瘢痕挛缩中的应用效果。方法选取2018年10月至2023年10月徐州医科大学附属淮海医院收治的98例烧伤后瘢痕挛缩患者进行回顾性分析,所有患者均采取皮瓣修复治疗,游离皮瓣组49例患者采取常规游离皮瓣移植术,菱形皮瓣组49例患者采取菱形皮瓣成形术。术后分别于6个月、1年对患者进行门诊复查随访,对比其皮瓣成活率与瘢痕复发率,受区瘢痕情况,并发症发生率及满意度,生活质量水平。结果菱形皮瓣组皮瓣成活率高于游离皮瓣组,瘢痕复发率低于游离皮瓣组(P<0.05);术后6个月、1年两组患者VSS评分均降低,菱形皮瓣组低于游离皮瓣组(P<0.05);菱形皮瓣组术后并发症发生率低于游离皮瓣组,满意度高于游离皮瓣组(P<0.05);术后6个月、1年两组患者36项健康调查简表(summary table of 36 health surveys,SF-36)评分均升高,菱形皮瓣组高于游离皮瓣组(P<0.05)。结论与常规游离皮瓣移植术相比,对烧伤后瘢痕挛缩患者采取菱形皮瓣成形术可提升皮瓣存活率,降低瘢痕复发率,改善受区瘢痕情况,同时可降低患者术后并发症发生率,提升患者满意度,改善其生活质量。展开更多
基金The project supported by the National Natural Science Foundation of China (19889210)
文摘In the framework of the finite element method (FEM), a prediction method for the heating rate and the skin friction on a body surface is presented by using the energy and momentum conservation equations respectively. Meanwhile, a brief analysis is made of the role the weighted functions play in the present work.
文摘Total skin electron therapy (TSET) is used for the treatment of Mycosis Fungoides. Several tech-niques have been developed, in order to achieve homogeneous dose distribution over the complete body surface. To implement a TSET technique, one has to optimize a variety of parameters. Monte Carlo simulation of TSET can facilitate this optimization. The aim of this study was to commission and optimize a TSET technique using the 4 and 6 MeV electron and the high dose rate facility on the Elekta Precise accelerator. The EGS4nrc/BEAMnrc Monte Carlo code was used. The beam data were calculated and measured at two different scoring planes for a single beam. The Model was validated by comparing the simulation with measurements. Two different vertical angles were used to obtain a uniform dose. The angle was optimized for best dose uniformity. The Rando phantom is placed on a rotating platform and rotates 60 degrees apart to facilitate the six patient position orientations. The doses delivered in a phantom by complete treatment were measured with Kodak EDR2 films and TLDs. The dose distribution varied among various scanning directions by 2 - 3 mm and 3 - 4 mm for 4 and 6 MeV respectively. The composite percentage depth dose of all six dual fields for the 4 and 6 MeV yielded an R80 of ~4 mm and ~6 mm, respectively. Dose uniformity was ±6% for 4 MeV and ±5% for 6 MeV. The bremsstrahlung contamination was 0.9% - 1.3%. Good agreements were found with published literature and inline with international protocols.
基金supported by the National Natural Science Foundation of China (11372243, 11372243, 1152219)the International Science and Technology Cooperation Program of China (2013DFG02930)
文摘Pain sensation may appear under long-lasting mechanical stimulation. Although people have the experience that pain sensation generally decreases with time while the stimulation remains, the underlying mechanism remains elusive. We experimentally studied the thermal and strain rate- dependent viscoelastic behavior of skin in uniaxial stretch and numerically investigated the effects of temperature and strain rate on pain sensation. The results indicate that the viscosity of skin tissue decreases with increasing temperature and reducing strain rate, which subsequently decreases the discharge frequency of skin nociceptor and thus relieves the pain sensation. The results would contribute to the understanding of pain relief mechanism and optimizing for mechanical treatment.
文摘目的应用心率变异性(heart rate variability,HRV)及皮肤交感神经活性(skin sympathetic nerve activity,SKNA)的方法,探讨持续非卧床腹膜透析(continuous ambulatory peritoneal dialysis,CAPD)与维持性血液透析(maintenance hemodialysis,MHD)患者在单次透析过程中自主神经张力变化及差异。方法纳入2021年2月─7月在南京医科大学第一附属医院肾科住院的CAPD患者及血液透析中心MHD患者,自透析开始(MHD患者自48h间隔后上机,CAPD患者晨起时更换夜间留腹透析液)采集4 h连续高频心电信号,依据透析方式不同分为CAPD组及MHD组,并比较2组患者透析中每30 min平均心率、全部正常窦性心搏间期的标准差(standard deviation of the interbeat interval of normal sinus beats,SDNN)、标准化低频功率(normalized low frequency power,LFn)、标准化高频功率(normalized high frequency power,HFn)、低频高频功率比值(LF/HF)及SKNA平均电压(average voltage of SKNA,aSKNA)的变化及组间差异。结果共纳入30例CAPD及50例MHD患者。2组患者第1、2个30 min的平均心率(t=-2.210、-2.426,P=0.037,0.018)及HFn(Z=2.226、2.027,P=0.026、0.043)有统计学差异,第2个30 min的LFn有统计学差异(t=-2.548,P=0.013)。透析后,2组患者均表现出LF/HF升高(Z=3.162,2.980,P=0.011,0.020),MHD组变化更早;MHD组平均心率增加(q=3.336,P=0.009),HFn降低(Z=4.123,P<0.001)。各时段aSKNA 2组相比无统计学差异(0.010<|Z|<1.109,均P>0.05),但MHD组动态变化更大(Z>3.125,P<0.05)。结论MHD患者较CAPD患者在单次透析中自主神经指标变化更大。
文摘目的探讨菱形皮瓣成形术在烧伤后瘢痕挛缩中的应用效果。方法选取2018年10月至2023年10月徐州医科大学附属淮海医院收治的98例烧伤后瘢痕挛缩患者进行回顾性分析,所有患者均采取皮瓣修复治疗,游离皮瓣组49例患者采取常规游离皮瓣移植术,菱形皮瓣组49例患者采取菱形皮瓣成形术。术后分别于6个月、1年对患者进行门诊复查随访,对比其皮瓣成活率与瘢痕复发率,受区瘢痕情况,并发症发生率及满意度,生活质量水平。结果菱形皮瓣组皮瓣成活率高于游离皮瓣组,瘢痕复发率低于游离皮瓣组(P<0.05);术后6个月、1年两组患者VSS评分均降低,菱形皮瓣组低于游离皮瓣组(P<0.05);菱形皮瓣组术后并发症发生率低于游离皮瓣组,满意度高于游离皮瓣组(P<0.05);术后6个月、1年两组患者36项健康调查简表(summary table of 36 health surveys,SF-36)评分均升高,菱形皮瓣组高于游离皮瓣组(P<0.05)。结论与常规游离皮瓣移植术相比,对烧伤后瘢痕挛缩患者采取菱形皮瓣成形术可提升皮瓣存活率,降低瘢痕复发率,改善受区瘢痕情况,同时可降低患者术后并发症发生率,提升患者满意度,改善其生活质量。
