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1.
细胞内游离钙在运动心脏重塑中的作用   总被引:13,自引:5,他引:8  
本文建立了运动心脏的实验动物模型,应用激光扫描共聚焦显微镜与新一代钙荧光指示剂Fluo-3/AM的方法,对心肌活细胞内具有生物活性的游离钙的动态变化进行了研究,以期了解运动心脏结构与功能重塑的细胞机制。结果显示:经过12周耐力训练后,心肌细胞内游离钙浓度静息值无显著性改变,心肌收缩时其游离钙浓度峰值较对照组显著增高11%(P<0.05)。停止训练8周后,心肌收缩时胞内游离钙浓度峰值较训练时显著降低14%(P<0.05),恢复到正常对照水平。研究结果提示,运动心脏可保持细胞内钙稳态,心肌收缩时收缩结构钙可获得量增多,是运动心脏心肌收缩性增强的重要机制之一,同时,心肌细胞内游离钙的增多对于运动心脏肥大的发生也起重要的介导作用,而且,运动心肌细胞内游离钙的改变是一种可逆性变化。  相似文献   

2.
运动心脏内分泌功能可复性的研究   总被引:31,自引:4,他引:27  
为了进一步探讨运动心脏的可复性及其与病理心脏的本质差异,通过动物实验模拟运动心脏,观察了停止运动训练8周后心脏重量的变化,并对心肌组织与血浆中心钠素和降钙素基因相关肽含量进行了放射免疫测定。结果显示,经过12周耐力训练后,心脏重量指数显著增高51%;心房肌组织与血浆中心钠素含量分别显著增高49%和79%;心房肌组织与血浆中降钙素基因相关肽含量分别显著增高36%和19%。停止训练8周后,心脏重量指数较训练时显著降低24%,心脏绝对重量和心脏重量指数与其对照组无显著差异;心房肌组织与血浆中心钠素含量分别较训练时显著降低22%和33%,基本恢复到正常对照水平;心房、心室肌组织与血浆降钙素基因相关肽含量分别较训练时降低17%、8%和3%,也恢复到正常对照水平。研究结果表明,运动心脏确有心肌肥大,同时,运动心肌组织,尤其心房组织中心钠素和降钙素基因相关肽的产生与分泌水平增高,对运动性心肌肥大的发生、心肌收缩性的增强及冠脉循环的改善起重要调节作用。停训后运动心肌细胞心钠素和降钙素基因相关肽的改变不仅表明运动心脏内分泌功能改变具有可复性,而且,进一步证实运动心脏与病理心脏有着本质的差别。  相似文献   

3.
本文对经过上、下坡跑台耐力训练的大鼠心肌毛细血管进行了研究,结果表明,毛细血管壁上ATP_(ase)、AKP活性反应增强;毛细血管密度(CD)和毛细血管与心肌纤维的比值(C/F)增高;毛细血管内皮细胞胞浆中微饮小泡增多,毛细血管腔面微绒毛状结构增多。两种训练方式下左、右心室毛细血管的改变基本一致。提示,耐力训练后心肌毛细血管产生了良好的适应性变化,有利于运动心脏的血液供应。  相似文献   

4.
间歇性低氧训练对急性运动大鼠心肌超微结构的影响   总被引:10,自引:1,他引:9  
对SD大鼠进行 4周的间歇性低氧训练后 ,电镜下观察其急性运动后心肌组织的超微结构变化 ,并进行形态计量学分析。结果显示 :间歇性低氧训练和有氧运动相结合 ,可对心肌肌原纤维间线粒体的数量和体积产生一定影响 ,并通过线粒体体积密度的增高和线粒体内膜及嵴的表面密度的增大 ,提高有氧代谢能力  相似文献   

5.
不同运动负荷小鼠心肌活细胞游离钙动态变化的LSCM研究   总被引:5,自引:0,他引:5  
目的 :探讨运动与心脏重塑的生物学机制中心肌细胞内游离钙的动态变化。方法 :采用激光扫描共聚焦显微技术 ,对不同运动负荷条件下小鼠心肌活细胞内游离钙浓度的变化进行观察、记录和分析 ,采用多道生理记录仪经颈动脉插管 ,对不同运动负荷条件下小鼠心肌收缩功能进行记录与分析。结果 :与对照组比较 ,有氧运动组心脏发生肥大 ,左室内压力二阶导数增加了 47 1 7%(P <0 0 0 1 ) ,表明心肌收缩功能增强 ,静息期心肌细胞内游离 [Ca2 + ]i 基值无显著性变化 ,峰值显著性增加了 1 5 7 2 % (P <0 0 0 1 ) ,达峰时间延长了 3 8 5 % (P <0 0 0 1 ) ;大强度疲劳组心肌肥大 ,但心肌收缩功能降低 (-3 5 2 4% ,P <0 0 0 1 ) ,静息期心肌细胞内游离 [Ca2 + ]i 基值和峰值分别显著增加了 41 9% (P <0 0 0 1 )和 2 0 6 3 % (P <0 0 0 1 ) ,达峰时间延长了 74 8% (P <0 0 0 1 )。有氧运动组与大强度疲劳组比较 ,心肌细胞内游离 [Ca2 + ]i 峰值和达峰时间均有显著性差异 (P <0 0 0 1 )。结论 :不同运动负荷影响心肌细胞内游离 [Ca2 + ]i 的变化 ,大强度疲劳训练可导致心肌细胞内游离[Ca2 + ]i 和静息态基值大幅度升高 ,峰值后移  相似文献   

6.
有氧运动训练后大鼠横纹肌线粒体DNA含量观察   总被引:6,自引:1,他引:5  
有氧运动训练能使肌肉组织产生适应性变化.从而提高运动耐力.本研究通过不同运动训练方案(无负重游泳3天.60分/天;7天,60分/天;12天,60分/天)、训练及注射钙鳌合剂(EGTA)、氧化剂(GSSG),观察大鼠骨骼肌、心肌线粒体DNA含量的变化规律.结果发现,运动训练3天后,骨骼肌线粒体DNA即表现为增加(57%),7天后降为42%.12天后即不再增加,而此时注射GSSG的训练大鼠线粒体DNA仍增加了26%;心肌线粒体DNA只有在训练12天并注射了GSSG才表现为增加(30%),说明改变细胞内的氧化应激的平衡(有氧运动训练及注射GSSC)可以影响线粒体DNA的生物合成.注射EGTA并训练的大鼠,骨骼肌线粒体则表现为没有显著变化,而在心肌线粒体7天和12天后出现了DNA合成的抑制(-30%,-32%),说明细胞内外的钙平衡也会影响线粒体DNA的生物合成.  相似文献   

7.
急性心肌梗塞的MRI特征及其超微病理基础   总被引:1,自引:1,他引:0  
目的 探讨急性心肌梗塞后不同心肌损伤区的MRI特征及其超微病理学基础。方法 结扎兔冠状动脉左前降支 2 4h制作AMI模型 10只 ,行常规MRI、对比剂动态增强MRI、电影MRI及多巴酚丁胺负荷试验。放射微球测定心肌血流量 ,伊文氏蓝和TTC染色确定缺血和梗塞心肌 ,并制作电镜标本观察肌原纤维和线粒体的改变 ,测定病变值和对损伤程度分级。结果 AMI后T1信号无明显改变 ,T2 信号增高 ,40 %可见病变局部心肌壁变薄 ,60 %可见病变邻近左室腔内异常血流高信号 ;正常、缺血和梗塞心肌动态增强时间 -信号强度曲线表现不同 ;cine -MRI表现为局部室壁变薄、运动减弱 ,多巴酚丁胺负荷表现为室壁变厚、运动增强。病变心肌较正常肌含水量显著增高而血流显著减少。正常、缺血及梗塞心肌线粒体体密度、数密度存在显著差异。结论 AMI的MRI表现与心肌超微结构损伤程度及残余血流量有关  相似文献   

8.
运动训练与心肌毛细血管   总被引:2,自引:1,他引:1  
<正> 身体负荷时,机体对于能量物质的需求增加。为了满足机体运动器官的能量供应,心脏必须加强收缩,增加心输出置。由于心肌毛细血管与心肌组织的能量供应息息相关,所以,运动训练与心肌毛细血管的研究是多年来研究运动心脏的专家们的热门课题。本文着重从运动训练与心肌毛细血管分布入手,总结前人的研究结果。  相似文献   

9.
运动和胰岛素对骨骼肌作用的组织差异性   总被引:1,自引:0,他引:1  
<正> 运动和胰岛素都能促进骨骼肌的葡萄糖吸收和葡萄糖的代谢。体内外许多研究表明两者对骨骼肌代谢的这种调节作用表现出明显的组织差异性。1 骨骼肌肌纤维类型的生理、生化特性人的红肌肌原纤维ATP和线粒体酶活性,肌红蛋白含量和毛细血管密度都高于白肌肌原纤维,结合代谢特性,哺乳类骨骼肌肌纤维又可分为:慢收缩  相似文献   

10.
游泳训练对大鼠脊髓神经元线粒体超微结构的影响   总被引:1,自引:1,他引:0  
目的 :观察游泳训练对大鼠脊髓神经元线粒体结构的影响。方法 :采用循环水逆流游泳运动方式 ,对游泳训练大鼠脊髓前角运动神经元线粒体超微结构进行形态计量学分析。结果 :与对照组相比 ,(1 )游泳后大鼠脊髓前角运动神经元线粒体数目增多 ,体积增大 ,线粒体嵴致密 ,基质电子密度增高 ,部分线粒体(4 3 6% )有明显的退行性改变。 (2 )游泳组动物的线粒体的体密度 (Vv)、数密度(Nv)、面密度 (Sv)均有明显增加(P<0 0 1 ) ,其中以体密度增加较为显著  相似文献   

11.
Acute limping may be the result of multiple pathologies in children. The differential diagnosis varies based on the age of the child. Irrespective of age, the initial imaging work-up includes AP and frog leg radiographs of the pelvis and ultrasound; MRI may sometimes be helpful. In children less than 3 years, infections and trauma are most frequent. MRI is the imaging modality of choice when osteomyelitis is clinically suspected. Between the ages of 3 and 10 years, transient synovitis of the hip and Legg-Calvé-Perthes disease are main considerations but infection, inflammation and focal bony lesions are also considered. In children over 10 years, slipped capital femoral epiphysis also is considered.  相似文献   

12.
KEY POINTS ·High-intensity interval training(HIT)is characterized by repeated sessions of relatively brief,intermittent exercise.often performed with an“a11 out”effort or at an intensity close to that which elicits peak oxygen uptake(i.e.,≥90%of VO2 peak).  相似文献   

13.
In response to the ENFSI and EDNAP groups’ call for new STR multiplexes for Europe, Promega® developed a suite of four new DNA profiling kits. This paper describes the developmental validation study performed on the PowerPlex® ESI 16 (European Standard Investigator 16) and the PowerPlex® ESI 17 Systems. The PowerPlex® ESI 16 System combines the 11 loci compatible with the UK National DNA Database®, contained within the AmpFlSTR® SGM Plus® PCR Amplification Kit, with five additional loci: D2S441, D10S1248, D22S1045, D1S1656 and D12S391. The multiplex was designed to reduce the amplicon size of the loci found in the AmpFlSTR® SGM Plus® kit. This design facilitates increased robustness and amplification success for the loci used in the national DNA databases created in many countries, when analyzing degraded DNA samples. The PowerPlex® ESI 17 System amplifies the same loci as the PowerPlex® ESI 16 System, but with the addition of a primer pair for the SE33 locus. Tests were designed to address the developmental validation guidelines issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM), and those of the DNA Advisory Board (DAB). Samples processed include DNA mixtures, PCR reactions spiked with inhibitors, a sensitivity series, and 306 United Kingdom donor samples to determine concordance with data generated with the AmpFlSTR® SGM Plus® kit. Allele frequencies from 242 white Caucasian samples collected in the United Kingdom are also presented. The PowerPlex® ESI 16 and ESI 17 Systems are robust and sensitive tools, suitable for the analysis of forensic DNA samples. Full profiles were routinely observed with 62.5 pg of a fully heterozygous single source DNA template. This high level of sensitivity was found to impact on mixture analyses, where 54–86% of unique minor contributor alleles were routinely observed in a 1:19 mixture ratio. Improved sensitivity combined with the robustness afforded by smaller amplicons has substantially improved the quantity of data obtained from degraded samples, and the improved chemistry confers exceptional tolerance to high levels of laboratory prepared inhibitors.  相似文献   

14.
Objective To evaluate the preliminaily clinical efficacy and retrievability of a retrievable hinged covered metallic stent in the treatment of the bronchial stump fistula (BSF). Methods Between April 2003 and March 2005, 8 patients with bronchial stump fistula after pneumonectomy or lobectomy were treated with two types (A and B) of retrievable hinged covered metallic stents. Type A stent was placed in 6 patients and type B in 2 under fluoroscopic guidance. The stent was removed with a retrieval set when BSF was healed or complications occurred. Results Stent placement in the bronchial tree was technically successful in all patients, without procedure-related complications. Immediate closure of the BSF was achieved in all patients after the procedure. Stents were removed from all patients but one. Removal of the stents was difficult in two patients due to tissue hyperplasia. Patients were followed up for 6 - 21 months. Placement of the stents remained stable in all patients except one due to severe cough. Permanent closure of BSF was achieved in 7 (87.5%) of 8 patients. Conclusion Use of a retrievable hinged covered expandable metallic stent is a simple, safe, and effective procedure for closure of the BSF. Retrieval of the stent seems to be feasible. (J Intervent Radiol, 2007, 16: 253-257)  相似文献   

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Zusammenfassung Bei der rechtsmedizinischen Identifizierung kann die Identität im strengen Sinn allenfalls bei lebenden Personen festgestellt werden; sonst läßt sich nur von Teilen auf das Ganze (vom Untersuchungsobjekt auf die Person) schließen, wobei die verschiedenen Merkmale des Untersuchungsobjektes entsprechend der Hdufigkeit ihres Vorkommens eine unterschiedliche Beweiskraft haben. Bei der Schädelidentifizierung mit Hilfe moderner photographischer oder elektronischer Superprojektionsverfahren ergeben sich unter Berücksichtigung der Weichteildicken so viele (fiktive) Vergleichspunkte, daß bei geeignetem Vergleichsmaterial (Photographien) Identität wegen der Vielzahl übereinstimmender Bezugspunkte in den meisten Fällen evident ist.  相似文献   

19.
This is a review of the role of imaging procedures for the assessment of abdominal and pelvic lymph nodes. The diagnosis of malignant lymphatic spread is rarely the sole purpose of imaging, because it is usually part of a general abdominal examination, most frequently with CT or US, or increasingly with MRI. These studies are often requested in order to obtain information about the situation to be encountered during surgery, or to alert the surgeon to irresectability or to unexpected metastases outside the initially planned area of exploration. In most surgically treated tumours the role of imaging for preoperative staging is limited, due either to its insufficient sensitivity or because the initial treatment is independent of the lymph node stage. Imaging is commonly used to verify treatment response to chemo- or radiotherapy and for follow-up.Correspondence to: S. Delorme  相似文献   

20.
目的:探索CT-SIM三维定位系统、体模固定技术和PET-CT融合影像导引定位技术在胸部肿瘤经皮穿刺活检中的应用价值。方法:对380例胸部肿瘤患者行改进的CT定位技术下的经皮穿刺活检术。根据肿瘤的大小、深度、毗邻关系、活动度以及患者的心肺功能状态,综合运用CT-SIM系统、体模固定技术和PET-CT融合影像导引技术,为患者进行穿刺前定位。统计穿刺定位时间长度、成功率、确诊率、并发症发生情况,并与210例采用传统铅栅定位下胸部肿瘤穿刺活检的相应资料进行比较。结果:采用改进的CT定位技术的380例患者穿刺定位精确,平均定位时间(9.5 min)较传统方法(16.8 min)缩短7.3 min,活检成功率和确诊率分别是98.7%和95.3%,高于传统定位方法的93.3%和83.3%,两者差异均具有统计学意义(P〈0.05)。穿刺并发症发生率相似,气胸发生率分别为2.8%和2.9%,咯血发生率分别为11%和12.8%。结论:根据患者状态及肿瘤特点,在CT-SIM系统快速精确定位技术的基础上,综合运用体模固定技术和PET-CT融合影像导引技术,能显著缩短经皮穿刺活检的定位时间,提高活检成功率。  相似文献   

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