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1.
Ca2+介导严重烧伤早期心肌线粒体呼吸功能损害   总被引:1,自引:0,他引:1  
目的 :探讨Ca2 + 在严重烧伤早期心肌线粒体呼吸功能损害中的作用及其机制。方法 :复制 30 %TBSAⅢ度烧伤大鼠模型 ,取正常及伤后 1、3、6、12、2 4h大鼠心肌分离线粒体 ,测其呼吸功能、Ca2 + 浓度 ([Ca2 + ]m)、F0 F1-ATPase和细胞色素c氧化酶活性 ,同时观察心肌线粒体能量代谢变化。结果 :①伤后 1h [Ca2 + ]m 即明显升高 ,同时心肌线粒体呼吸功能加强 ,呼吸控制率(RCR)、Ⅲ态呼吸速率升高 ,且RCR与 [Ca2 + ]m 呈显著正相关 (r=0 .8415 ,P <0 .0 1) ;伤后 3、6、12、2 4h心肌 [Ca2 + ]m 升高更加明显 ,但线粒体呼吸功能反而下降 ,RCR与 [Ca2 + ]m 均呈显著负相关。②F0 F1-ATPase活性于伤后 1h明显降低 ,但 3h显著高于对照组 ,6、12、2 4h再度下降 ;伤后 3、6、12、2 4h线粒体细胞色素c氧化酶活性分别下降 42 .5 %、36 .2 %、32 .3%和 18.9%。③大鼠烧伤后 1h心肌线粒体ATP含量无明显变化 ,但 3、6、12、2 4h线粒体ATP含量均显著降低 ,同时ADP含量升高。结论 :烧伤初始 [Ca2 + ]m 适度升高 ,促进线粒体呼吸功能加强 ;烧伤后续阶段Ca2 + 严重超载在线粒体呼吸功能损害中起重要作用。  相似文献   

2.
烧伤脓毒症早期心肌内泛素mRNA的表达变化及意义   总被引:1,自引:0,他引:1  
目的 观察烧伤脓毒症大鼠心肌内泛素mRNA表达的变化及意义。方法 采用大鼠 30 %Ⅲ度烫伤复合腹腔注射内毒素(6mg/kg)动物模型 ,分为伤后 2h和 6h组 ,同时设对照组 ,通过核糖核酸印迹法检测大鼠心肌内泛素mRNA表达的变化。结果 伤后 2h和 6h大鼠心肌内泛素mRNA 2 4kb条带和 1 2kb条带的表达均较对照组均显著升高 ,其中 2 4kb条带的升高更明显 (P<0 0 1)。提示烧伤脓毒症早期心肌内重要的蛋白降解途径———泛素系统活性呈持续增强现象 ,预示蛋白降解代谢可能显著增加。结论 该发现对进一步从代谢角度研究烧伤脓毒症时心肌结构的变化及其对心功能的影响有重要意义。  相似文献   

3.
力竭游泳对红细胞膜的影响   总被引:25,自引:2,他引:23  
目的进一步探讨运动贫血的发生机理,为防治运动性贫血提供一定理论依据.方法采用荧光法和比色法分别测定力竭游泳后红细胞膜MDA含量、红细胞变形性、Na+-K+-ATPase、Ca2+-ATPase活性以及红细胞膜总磷脂、胆固醇含量及其比值.结果与对照组相比,MDA含量在运动后即刻和1h极显著升高(p<0.01),24h后仍高于对照组(p<0.05);红细胞变形性在运动后即刻,运动后1h显著下降(<0.05;p<0,01),24h后仍未恢复正常;Na+-K+-ATPase和Ca2+-ATPase活性在运动后即刻和1h显著下降(p<0.05),24h后基本恢复到正常;红细胞膜总磷脂在运动后即刻显著下降(p<0.05),并在1h后恢复正常;红细胞膜上胆固醇在运动后即刻极显著低于对照组(p<0.01),1h和24h后仍显著低于对照组;红细胞膜上胆固醇/磷脂比值在运动后即刻和1h均显著低于对照组(p<0.05),24h后基本恢复正常;相关分析表明,红细胞的变形性与红细胞膜上MDA含量呈显著负相关(p<0.05).结论力竭游泳运动引发的自由基产生和脂质过氧化对红细胞膜结构有损害,使Na+-K+-ATPase和Ca2+-ATPase活性下降,红细胞膜上的磷脂和胆固醇含量以及其比值降低,致使红细胞变形性下降,可能是造成运动性贫血的重要原因之一.  相似文献   

4.
高住低训对大鼠心肌线粒体呼吸链酶复合物活性的影响   总被引:1,自引:1,他引:0  
目的:探讨高住低训(HiLo)习服过程中大鼠心肌线粒体呼吸链酶复合物活性的动态变化。方法:40只SD大鼠分为5组:常氧对照组以及HiLo1、2、3、4周组,每组8只。HiLo组大鼠每天在模拟海拔2500m(氧含量约为15.4%)的环境生活,在模拟海拔1300m(氧含量约为19.4%)环境游泳1h,每周6天。通过光谱分析法,观察在1~4周时间内,在HiLo作用下大鼠心肌线粒体呼吸链酶复合物Ⅰ(NADH-CoQ还原酶)、复合物Ⅱ(琥珀酸-CoQ还原酶)、复合物Ⅲ(CoQ-细胞色素C还原酶)和复合物Ⅳ(细胞色素氧化酶)活性的变化。常氧对照组不进行运动,测试指标与运动组相同。结果:HiLo1周组大鼠心肌线粒体酶复合物Ⅰ、Ⅱ、Ⅲ、Ⅳ活性与对照组相比均显著下降(P<0.05,P<0.01)。HiLo2周组除酶复合物Ⅲ外,其他三种酶复合物活性均显著低于对照组(P<0.05,P<0.01)。HiLo3周组心肌线粒体酶复合物Ⅰ、Ⅱ、Ⅲ、Ⅳ活性与对照组相比差异无统计学意义;但线粒体蛋白含量显著升高(P<0.05)。HiLo4周组心肌线粒体酶复合物Ⅰ、Ⅱ、Ⅳ活性显著升高(P<0.05,P<0.01);线粒体蛋白含量显著升高(P<0.05)。结论:大鼠心肌线粒体呼吸链酶复合物Ⅰ、Ⅱ、Ⅲ、Ⅳ活性在HiLo的习服过程中需要3周时间。  相似文献   

5.
丹参对烧伤大鼠心肌细胞线粒体功能影响的实验研究   总被引:2,自引:0,他引:2  
目的:探讨丹参对烧伤大鼠心肌细胞线粒体呼吸功能及氧自由基的影响。方法:96只SD大鼠随机分为对照组(A)、烧伤组(B)、治疗组(C)。B组和C组造成20%总体表面积Ⅲ度烧伤。在伤后1、2、6小时,动态检测心肌细胞线粒体内细胞色素aa3、细胞色素C、能荷和超氧化物歧化酶(SOD)水平。结果: (1)伤后2小时内,B、C组心肌细胞线粒体内细胞色素aa3水平无显著降低(P>0.05)。伤后6小时,B、C组心肌细胞线粒体内细胞色素aa3水平显著低于A组<0.05);同时C组显著高于B组(P<0.05);(2)伤后1小时开始,心肌细胞线粒体内细胞色素C水平、能荷和SOD活力均呈进行性下降改变;C组显著高于B组(P<0.05)。结论:丹参能显著提高细胞色素aa3、细胞色素C、能荷和SOD;明显改善大鼠烧伤后心肌细胞线粒体呼吸功能及明显减少氧自由基的产生。  相似文献   

6.
目的 观察刨伤性脑损伤(traumatic brain injury,TBI)大鼠脑组织匀浆及线粒体Na+-K+-ATP酶、Ca2+-ATP酶活性、神经细胞内游离Ca2+浓度及脑组织钙调蛋白(CaM)表达的动态变化,探讨脑复合剂脑保护作用的分子生物学机制.方法 建立大鼠TBI模型,分别设立假手术组、TBI组及中药治疗组.中药治疗组给予脑复合剂10 g·kg-1·d-1,假手术组及TBI组给予同等剂量等渗盐水,2次/d,连续7 d.分别于TBI后24 h、72 h、1周等3个时相点处死大鼠,动态定量分析各组大鼠脑组织匀浆及线粒体Na+-K+-ATP酶、Ca2+-ATP酶活性、神经细胞内游离Ca2+浓度及脑组织CaM表达的变化.结果 TBI组各时相点大鼠脑组织匀浆及线粒体Na+-K+-ATP酶、Ca2+-ATP酶活性均明显降低,于TBI后72 h后逐渐恢复,1周时仍明显低于假手术组.中药治疗组大鼠脑组织Na+-K+-ATP酶、Ca2+-ATP酶活性显著增加(P<0.05);TBI组各时相大鼠脑组织神经细胞内游离Ca2+浓度及脑组织CaM表达均有不同程度增高,于伤后24 h达高峰,持续至72 h仍高于假手术组.而中药治疗组各时相大鼠神经细胞内游离Ca2+浓度及脑组织CaM表达明显低于TBI组(P<0.05).结论 脑复合剂的脑保护作用可能与增加脑组织Na+-K+-ATP酶、Ca2+-ATP酶的活性,从而减轻TBI后脑细胞的能量代谢障碍,降低神经细胞内游离Ca2+浓度及脑组织CaM表达,减轻Ca2+超载所导致的继发性脑损伤有关.  相似文献   

7.
目的 观察核因子 κB(NF κB)对烧伤脓毒症大鼠骨骼肌蛋白分解代谢的影响 ,并探讨其可能机制。方法 采用 30 %TBSAⅢ度烫伤加内毒素攻击大鼠为模型模拟临床烧伤脓毒症 ,10 5只Wistar大鼠随机分为正常对照组、烧伤脓毒症组、烧伤脓毒症 NF κB抑制剂二硫代氨基甲酸吡咯烷 (PDTC)组 ,采用凝胶电泳迁移率改变分析法 (EMSA)分析骨骼肌NF κB活性的变化 ,高效液相色谱分析法测定酪氨酸和 3 甲基组氨酸。结果 可见烧伤脓毒症大鼠伸趾长肌总蛋白、肌纤维蛋白降解率在伤后 2h即较对照组即显著升高 ,之后逐渐上升 ,以 12h升高最显著 (P <0 0 1) ;而骨骼肌NF κB的活性于伤后 2h显著升高 ,之后呈现下降趋势 ,伤后 12h其活性仍显著高于正常对照组 (P <0 0 5 )。结论 研究表明NF κB于烧伤脓毒症大鼠的骨骼肌中明显活化 ,而应用NF κB抑制剂PDTC能够明显降低脓毒症时骨骼肌代谢率 ,说明NF κB可能参与调控烧伤脓毒症时骨骼肌的异常代谢。  相似文献   

8.
以大鼠力竭运动为模型,研究了牛磺酸对心肌中环磷酸腺苷(cAMP)、环磷酸鸟苷(cGMP)水平和心肌线粒体钙离子含量的影响.结果发现:力竭运动可造成大鼠心肌中cAMP和cGMP水平显著升高,心肌线粒体Ca2+含量显著增加,造成心肌线粒体和心肌的损伤,而牛磺酸可显著抑制力竭运动后大鼠心肌中cAMP、cGMP的升高,抑制心肌线粒体的钙超载.结果提示:牛磺酸可显著抑制力竭运动后大鼠心肌第二信使水平的升高及心肌线粒体中钙超载现象,说明牛磺酸有减轻和防止力竭运动后心肌损伤的作用.  相似文献   

9.
目的 :探讨快速补液对烧伤延迟复苏后心肌局部血流量的改善作用。方法 :采用大鼠 30 %TBSA(Ⅲ°)烧伤模型 ,分为快速补液组 (RI组 )和均匀补液组 (AI组 ) ,采用氢廓清法测定伤前、伤后 1、3、6、1 2、2 4、48h的心肌局部血流量 ,同时行心肌组织光镜和电镜形态学观察。结果 :伤后 1h ,心肌局部血流量降低 ,6h达最低点。补液后 ,心肌局部血流量显著升高 ,RI组的升高幅度显著大于AI组。形态学观察表明 ,RI组的心肌损害较AI组轻。结论 :快速补液能够改善心肌局部血流量 ,从而可减轻心肌损害。  相似文献   

10.
缺血缺氧在大鼠烧伤后"休克心"中的作用及其机制探讨   总被引:39,自引:0,他引:39  
目的 探讨缺血缺氧在烧伤后“休克心”中的作用及其机制。 方法 健康成年Wistar大鼠 15 0只 ,分为对照组 (2 5只 )和 30 %TBSAⅢ度烧伤组 (12 5只 ) ,其中烧伤组又分为 1,3,6 ,12和 2 4h组 ,每组 2 5只。检测心肌收缩功能、心肌微血管通透性分值、心肌局部血流量、血浆中心肌肌球蛋白轻链 1(CMLC1)、心肌组织核转录因子 (NF -κB)活性、髓过氧化物酶 (MPO)、TNFαmRNA表达和心肌组织TNFα含量。 结果 伤后 1h ,心肌微血管通透性分值即开始增高 ,2 4h达对照值的 2 .1倍 ;心肌局部血流量显著降低 ,伤后 2 4h仍显著低于对照水平 ;CMLC1增高达对照组的 18.6倍。心肌组织NF -κB活性和TNFαmRNA表达明显增强 ,心肌组织TNFα含量增高。心肌组织MPO活性升高。左心室收缩峰压 (LVSP)、最大左心室等容收缩期中心室内压上升 下降的最大速率 (±dp dtmax)均显著降低 ,而左心室舒张末压 (LVEDP)上升 ,表明心肌收缩功能和舒张功能均减退。 结论 缺血缺氧造成了心肌严重损害 ,心肌组织NF -κB活性明显增强 ,心肌细胞TNFα等促炎因子表达上调是烧伤后“休克心”的重要因素。  相似文献   

11.
12.
成批煤气爆燃烧伤的救治体会   总被引:1,自引:0,他引:1  
报道治疗因煤气泄漏爆炸烧伤病员7例,经应用MEBT技术积极救治,其中6例于伤后17天痊愈出院,另一例特重伤员也于伤后30天康复出院。作者认为:应严格按照MEBT/MEBO要求进行规范治疗,正确处理生命体征、休克、感染、脏器功能和创面的辨证关系。同时,不能忽视外科营养在过程中的重要作用,它是创面修复的物质保证。  相似文献   

13.
In situations of stress, such as clinical trauma, starvation or prolonged, strenuous exercise, the concentration of glutamine in the blood is decreased, often substantially. In endurance athletes this decrease occurs concomitantly with relatively transient immunodepression. Glutamine is used as a fuel by some cells of the immune system. Provision of glutamine or a glutamine precursor, such as branched chain amino acids, has been seen to have a beneficial effect on gut function, on morbidity and mortality, and on some aspects of immune cell function in clinical studies. It has also been seen to decrease the self-reported incidence of illness in endurance athletes. So far, there is no firm evidence as to precisely which aspect of the immune system is affected by glutamine feeding during the transient immunodepression that occurs after prolonged, strenuous exercise. However, there is increasing evidence that neutrophils may be implicated. Other aspects of glutamine and glutamine supplementation are also addressed.  相似文献   

14.
新疆石河子地区奶牛隐性乳房炎的调查与分析   总被引:1,自引:0,他引:1  
采用LMT法对新疆石河子地区三个规模化奶牛场泌乳牛群进行了隐性乳房炎检测,共检测994头泌乳牛3976个乳区.结果表明:奶牛隐性乳房炎阳性率为81.9%,乳区阳性率为49.1%.数据分析表明,不同年龄、胎次以及有无卧床奶牛的隐性乳房炎阳性率差异显著(P<0.05),后乳区的隐性乳房炎感染率显著高于前乳区感染率(P<0.05),隐性乳房炎乳区发生数也明显影响当日产奶量(P<0.05).  相似文献   

15.

Objectives

Women are resistant to neuromuscular fatigue compared to men in response to a range of exercise tasks. The sex differences in the neuromuscular responses to load carriage have yet to be investigated.

Design

Prospective cohort study.

Methods

Twenty-three male and 19 female British Army recruits completed a 9.7 km loaded march within 90 min, with the weight carried dependent on military trade (16 ± 2 kg for men and 15 ± 1 kg for women). Isometric maximal voluntary contraction (MVC) force of the knee extensors and vertical jump (VJ) height were examined pre- and post-loaded march to examine neuromuscular fatigue. Heart rate (HR) was recorded throughout and ratings of perceived exertion (RPE) was recorded following the march.

Results

HR was higher for women (173 ± 9 b min?1, 83 ± 6% heart rate reserve) than men (158 ± 8 b min?1, 72 ± 6% heart rate reserve) (p  0.001). RPE following the march was also higher for women than men (6 ± 2 vs 4 ± 2, respectively, p < 0.001). The loss in MVC force was greater for men than women (?12 ± 9% vs ?9 ± 13%, respectively, p = 0.031), however VJ height was impaired to a similar extent (?5 ± 11% vs ?5 ± 6%, respectively, p = 0.582).

Conclusions

The greater physiological stress during load carriage for women compared to men did not translate to a greater severity of knee extensor muscle fatigue, with women demonstrating fatigue resistance.  相似文献   

16.

Background

The local muscular endurance of knee flexors, during eccentric work in particular, is important in preventing or delaying kinematic changes associated with fatigue during treadmill running. This result, however, may not be transferable to overground running.

Objective

To test the hypothesis that overground running is associated with eccentric hamstring fatigue.

Methods

Thirteen runners (12 male and one female) performed an isokinetic muscle test three to four days before and 18 hours after a marathon. Both legs were tested. The testing protocol consisted of concentric and eccentric quadriceps and hamstring contractions.

Results

There were no significant differences between peak torque before and after the race, except that eccentric peak hamstring torque (both thighs) was reduced.

Conclusion

Overground running (running a marathon) is associated with eccentric hamstring fatigue. Eccentric hamstring fatigue may be a potential risk factor for knee and soft tissue injuries during running. Eccentric hamstring training should therefore be introduced as an integral part of the training programme of runners.  相似文献   

17.
目的:对42例肺心病慢性呼吸性酸中毒患者的80例次血气测定结果。方法:用不同的酸碱图(卡)及代偿公式进行酸碱类型的初步差别分析。结果:结合临床表现、各种影响因素与治疗反应等作出综合判定。结论:比较二种判定的差异,并提出较为实用、可靠的判断建议,以助于复合型呼吸性酸碱失衡的临床诊断与处理。  相似文献   

18.
Primary hyperoxaluria (PH1) is a rare inborn autosomal recessive metabolic disorder due to the deficiency of hepatic alanine-glyoxylate-aminotransferase. This deficiency results in excessive synthesis and urinary excretion of oxalate, inducing renal stone formation and deposition of calcium oxalate in the kidney, bone, myocardium, and vessels (systemic oxalosis, SO) in the most severely affected individuals. We report renal and skeletal changes in a 3-month-old girl with PH1 and SO. Intense cortico-medullary hyperechogenicity and increased homogeneous radiopacity of normal-sized kidneys suggested the diagnosis of SO. Skeletal survey showed osteopenia and characteristic symmetrical metaphyseal transverse bands in long bones, progressively becoming more dense and migrating towards the diaphysis. Multiple pathological and slowly healing fractures of the limbs occurred at the dense band level. A radiopaque rim was then observed in flat bones, epiphyseal nuclei, and vertebral bodies. Inflammatory granulomatous reaction, induced by the presence of oxalate crystals in the marrow spaces, coexisted with progressively evident radiological signs of secondary hyperparathyroidism, with partially overlapping features. The patient was treated by peritoneal dialysis and hemodialysis until combined liver–kidney transplantation. There are no previous reports of infants treated with hemodialysis for more than 2 years.  相似文献   

19.
Interventional oncology in private practice requires expert training and can be performed in a stand-alone facility for type 1 procedures in a hospital setting for type 2 and 3 procedures where subspecialized radiologists, state-of-the-art equipment, and postprocedure hospital monitoring are available. A multidisciplinary effort with oncologists, internal medicine physicians and anesthesiologists is necessary. The practice of interventional oncology requires around the clock availability, meticulous and established protocols and procedures and a financial investment. On the other hand, it is professionally gratifying because of constant technical advances and the impact on patients.  相似文献   

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