Background:Technological advancements in modern military and acrobatic jet planes have resulted in extraordinary psychophysiological loads being exerted upon flying personnel,including inducing neck and back pain.The ...Background:Technological advancements in modern military and acrobatic jet planes have resulted in extraordinary psychophysiological loads being exerted upon flying personnel,including inducing neck and back pain.The purpose of this study was to examine the effects of 12 weeks of functional strength training on 1)the volume and strength of the neck and shoulder muscles and 2)muscular activity upon exposure to helmets of different masses and elevated Gz forces in a long-arm centrifuge in high-performance aircraft personnel.Methods:Eighteen participants underwent 12 weeks of functional strength training(n=12)or the control protocol(n=6)without additional strength training.Pre-and post-intervention tests included evaluations of isometric strength of the head extensor muscles,flexion,and lateral flexion and rotation,as well as magnetic resonance imaging(MRI)to measure the volume of the m.sternocleidomastoideus,m.trapezius,and deep neck muscles.Furthermore,during a long-arm centrifuge(+1.4 and+3Gz)protocol,the muscular activity levels of the m.sternocleidomastoideus,m.trapezius and m.erector spinae muscles were assessed without a flight helmet,with a helmet,and with a helmet and night vision goggles.Each participant’s perception of muscular strain was noted immediately after the long-arm centrifuge protocol.Results:The maximal isometric strength in all exercises and muscle volumes increased in the training group but not the control group(P<0.05).Relative muscle activity(%MVC)with a helmet decreased after the intervention in the training but not the control group(P=0.01).Relative muscle activity while wearing a helmet and night vision goggles was higher after intervention in the control group than in the training group(P<0.01).The perceived muscular strain of the neck muscles induced by the long-arm centrifuge did not differ between the groups.Conclusions:Twelve weeks of functional strength training improves the maximal isometric strength and volume of neck and shoulder muscles and leads to lower relative muscle activation upon exposure to elevated Gz forces in a long-arm centrifuge.展开更多
目的探讨维持性血液透析患者慢性牙周炎与蛋白质能量消耗相关性。方法纳入新疆医科大学第一附属医院98例维持性血液透析(maintenance hemodialysis,MHD)患者,采用患者自评-主观全面评定量表诊断不同程度蛋白质能量消耗(Protein energy w...目的探讨维持性血液透析患者慢性牙周炎与蛋白质能量消耗相关性。方法纳入新疆医科大学第一附属医院98例维持性血液透析(maintenance hemodialysis,MHD)患者,采用患者自评-主观全面评定量表诊断不同程度蛋白质能量消耗(Protein energy wasting,PEW),采用社区牙周指数常规口腔检查方法诊断慢性牙周炎(Chronic periodontitis,CP),并检测超敏C反应蛋白(Hypersensitive c-reactive protein,hs-CRP)、白介素6(Interleukin-6,IL-6)及相关营养检测指标,建立多因素回归模型分析PEW的危险因素。结果MHD患者CP检出率为94.9%,重度CP组PEW的检出率为93.3%,重度PEW的患者均患牙周炎,中度牙周炎占35.3%,重度牙周炎64.7%。超敏C反应蛋白和铁蛋白随着牙周炎程度的加重而升高,重度牙周炎的MHD患者血肌酐、前白蛋白、总铁结合力较非CP组明显降低,多因素Logistic回归模型显示牙周炎为PEW的危险因素,合并牙周炎的MHD患者较无牙周炎的患者PEW的发生风险增加3倍。结论MHD患者慢性牙周炎检出率高,PEW与慢性牙周炎密切相关,临床工作中应该重视MHD患者牙周炎与PEW的综合干预和治疗。展开更多
文摘Background:Technological advancements in modern military and acrobatic jet planes have resulted in extraordinary psychophysiological loads being exerted upon flying personnel,including inducing neck and back pain.The purpose of this study was to examine the effects of 12 weeks of functional strength training on 1)the volume and strength of the neck and shoulder muscles and 2)muscular activity upon exposure to helmets of different masses and elevated Gz forces in a long-arm centrifuge in high-performance aircraft personnel.Methods:Eighteen participants underwent 12 weeks of functional strength training(n=12)or the control protocol(n=6)without additional strength training.Pre-and post-intervention tests included evaluations of isometric strength of the head extensor muscles,flexion,and lateral flexion and rotation,as well as magnetic resonance imaging(MRI)to measure the volume of the m.sternocleidomastoideus,m.trapezius,and deep neck muscles.Furthermore,during a long-arm centrifuge(+1.4 and+3Gz)protocol,the muscular activity levels of the m.sternocleidomastoideus,m.trapezius and m.erector spinae muscles were assessed without a flight helmet,with a helmet,and with a helmet and night vision goggles.Each participant’s perception of muscular strain was noted immediately after the long-arm centrifuge protocol.Results:The maximal isometric strength in all exercises and muscle volumes increased in the training group but not the control group(P<0.05).Relative muscle activity(%MVC)with a helmet decreased after the intervention in the training but not the control group(P=0.01).Relative muscle activity while wearing a helmet and night vision goggles was higher after intervention in the control group than in the training group(P<0.01).The perceived muscular strain of the neck muscles induced by the long-arm centrifuge did not differ between the groups.Conclusions:Twelve weeks of functional strength training improves the maximal isometric strength and volume of neck and shoulder muscles and leads to lower relative muscle activation upon exposure to elevated Gz forces in a long-arm centrifuge.