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91.
Infection is a rare complication of cardiac mural thrombus andmay prove difficult to diagnose and treat. We describe a patientwith infected thrombus associated with a left ventricular aneurysm,involving Salmonella typhimurium. Cross-sectional echocardiographyproved helpful in establishing the diagnosis.  相似文献   
92.
Regional cerebral blood flow after occlusion of the middle cerebral artery   总被引:3,自引:0,他引:3  
Occlusions of the middle cerebral artery (MCA) are mostly of embolic origin (appr. 80%) and give rise to about one third of all ischemic strokes, most of these being major strokes. MCA occlusions lasting for less than 1/2 h are tolerated without occurrence of permanent tissue damage. Occlusions lasting between 1/2 h to 4-8 h lead to permanent tissue damage and neurological deficits that are proportional to the duration of occlusion. Maximal tissue damage is obtained after 4-8 h occlusion. A cerebral blood flow of 8-23 ml/100 gr/min is sufficient for cellular viability but insufficient for normal tissue function ("ischemic penumbra"). Cellular function is completely abolished in the interval 8-16 ml/100 gr/min and flow at that level is tolerated only for 1-3 h before neuronal death ensues. In the interval 18-23 ml/100 gr/min there is some functional activity although it is reduced. Experimental and clinical evidence suggests that flow in this interval may be tolerated for several days, months or even longer ("chronic ischemic penumbra"). After MCA occlusion the blood flow falls below 8 ml/100 gr/min in most cases and permanent MCA occlusion always leads to relatively large areas of frank infarction. The ischemic infarcts may be surrounded by collaterally perfused areas where the blood flow is pressure-dependent (impaired autoregulation) and quite commonly insufficient for normal neuronal function (below 23 ml/100 gr/min). Such collaterally perfused areas may include a "chronic ischemic penumbra". Emboli causing MCA occlusions commonly disintegrate and/or migrate more peripherally within the first few weeks post stroke. This leads to reperfusion and changes of ischemic infarcts into hyperemic infarcts where flow is severely increased. The vascular reactivity is completely abolished in hyperemic infarcts and the hyperemic state lasts for about two weeks. Probably, anemic infarcts are equivalent to ischemic infarcts while the hemorrhagic variety is equivalent to hyperemic infarcts. The "partial infarct" with selective neuronal necrosis occurs in experimental animals after MCA occlusions of less than four h but not after permanent MCA occlusion. The significance of partial infarction in human stroke is not clarified. The extent of irreversible tissue damage can be reduced only if therapy sets in within 4-8 h after the occlusion. If a "chronic penumbra" exists the extension of reversible tissue damage can be reduced if therapy aimed at increasing the blood flow in the penumbra sets in within weeks or even months after the stroke.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
93.
目的 探讨应用介入方法治疗急性下肢缺血性疾病的临床效果及安全性。方法 21例患按基础病因不同分为两组,对无患肢慢性缺血史给予单纯动脉内灌注尿激酶,对存在有患肢慢性缺血史在给予适当尿激酶30万u后,应用超滑导丝通过闭塞段,顺导丝送入球囊导管行PTA术。结果 第1组8例,获得成功,1例于术后第3天死于急性左心功能不全;第2组9例获得成功,3例在发病5日后行截肢术。结论 (1)多种介入方法联合治疗急性下肢缺血临床效果可靠。(2)基础性病因是决定介入方法选择的首要因素。  相似文献   
94.
目的观察前列腺素E1(8μg·kg-1)与黄芪(225mg·kg-1)合用对家兔缺血心脏功能的影响.方法麻醉家兔冠脉结扎30min后再灌30min,测定左室舒张末期压(LVEDP).结果两药合用的疗效优于单药应用,减少缺血再灌注损伤心律失常的发生(P<0.01).结论前列腺素E1与黄芪合用对家兔缺血心脏功能的保护有显著的协同作用.  相似文献   
95.
目的验证超声彩色室壁动力学(CK)分析技术判断心肌梗死的准确性.方法结扎犬冠状动脉(冠脉)造成实验性急性心肌梗死模型,应用超声CK分析技术与病理解剖的结果进行对比性研究.结果结扎犬冠脉前超声CK图像由红-黄-绿-蓝色组成,色彩分布均匀,心内膜彩色移位(SEM)值为7.98~14.53mm结扎犬冠脉后造成实验性急性心肌梗死时超声CK图像绿-蓝色完全消失,仅遗留红-黄色,SEM值为1.27~6.45mm,与结扎前对比明显减少(P<0.05).超声CK图像检测的心肌梗死范围为(26.2±4.8)mm2,病理解剖测量为(22.5±4.7)mm2,两者对比显著相关(r=0.9264,P<0.01).结论超声CK图像有助于急性心肌梗死定性、定量诊断.  相似文献   
96.
磷酸肌酸停搏液对缺血心肌的保护作用   总被引:4,自引:0,他引:4  
王涛  李守先 《上海医学》2001,24(1):38-40
目的 探讨外源性磷酸肌酸(creatine phosphate,CP)在心脏直视手术中作为添加剂加入心脏停搏液中对缺血心肌的保护作用。方法 66例接受心内直视手术的患者分为对照组(I组)及试验组(Ⅱ组),各33例。I组使用冷晶体停搏液,Ⅱ组在I组停搏液中加入CP。于不同时段取血样检测5种心肌酶的含量。结果 两组心肌酶含量,术前差异无显著性;术后Ⅱ组心肌酶谱上升幅度低于I组,而下降速度则快于I组。结论 外源性CP加入心脏停搏液中对心肌具有良好的保护作用。  相似文献   
97.
磷酸肌酸心脏停搏液心肌保护临床观察   总被引:3,自引:0,他引:3  
目的研究磷酸肌酸对缺血/再灌注损伤心肌的保护机制.方法对16例进行双瓣膜替换术的患者,随机分成两组(各8例)对照组(单晶体停搏液组)和实验组(晶体停搏液中加入磷酸肌酸10mmol/L);分别于主动脉阻断前,开放后5、15、30、60、120min抽血测定乳酸(LA)、丙二醛(MDA)、超氧化物歧化酶(SOD)、黄嘌呤氧化酶(XOD);于阻断前,开放后2、24和48h测定心肌肌钙蛋白T(cTnT);两组部分患者于心脏阻断后即刻和主动脉开放前1min,取左心房心肌做电镜检查.结果开放后5、15、30min时实验组LA、MDA含量明显低于对照组(分别为P<0.05、O.01),SOD活性保持明显高于对照组(P<0.05),XOD组间无明显差异;开放后2、24、48h实验组cTnT显著低于对照组(P<0.01).心肌超微结构结果为对照组线粒体改变较实验组明显(2.725±0.832和l.872±0.542,P<0.001).结论磷酸肌酸具有为心肌细胞提供能量、保护细胞膜完整、维持心肌收缩蛋白正常的作用,可减轻心肌缺血/再于灌注损伤.  相似文献   
98.
目的 探讨霍金斯 (Hawkins)征在诊断距骨颈垂直骨折致距骨体缺血性坏死的价值 ,以及移位程度与缺血性坏死发生率的关系。方法 对 5 6例距骨颈骨折患者进行回顾性分析 ,判断有无Hawkins征 ,确定距骨颈骨折Hawkins征分型及 3种类型缺血性坏死的发生率。结果  2 4例缺血性坏死患者Hawkins征呈阴性 ,32例无缺血性坏死者呈阳性 ,三类骨折中移位较重的缺血性坏死发生率较高 (P <0 .0 1)。结论 Hawkins征在诊断距骨颈骨折致体部缺血性坏死中有较高的诊断价值 ,骨折移位程度是影响缺血性坏死发生率的重要因素之一。  相似文献   
99.
In secondary mitral regurgitation, the concept that the mitral valve (MV) is an innocent bystander, has been challenged by many studies in the last decades. The MV is a living structure with intrinsic plasticity that reacts to changes in stretch or in mechanical stress activating biohumoral mechanisms that have, as purpose, the adaptation of the valve to the new environment. If the adaptation is balanced, the leaflets increase both surface and length and the chordae tendineae lengthen: the result is a valve with different characteristics, but able to avoid or to limit the regurgitation. However, if the adaptation is unbalanced, the leaflets and the chords do not change their size, but become stiffer and rigid, with moderate or severe regurgitation. These changes are mediated mainly by a cytokine, the transforming growth factor‐β (TGF‐β), which is able to promote the changes that the MV needs to adapt to a new hemodynamic environment. In general, mild TGF‐β activation facilitates leaflet growth, excessive TGF‐β activation, as after myocardial infarction, results in profibrotic changes in the leaflets, with increased thickness and stiffness. The MV is then a plastic organism, that reacts to the external stimuli, trying to maintain its physiologic integrity. This review has the goal to unveil the secret life of the MV, to understand which stimuli can trigger its plasticity, and to explain why the equation “large heart = moderate/severe mitral regurgitation” and “small heart = no/mild mitral regurgitation” does not work into the clinical practice.  相似文献   
100.
Objective: The present study aimed to evaluate the therapeutic effect and explore the underlying mechanisms of Longxue Tongluo Capsule (LTC) on ischemic stroke rats. Methods: Twenty-six rats were randomly divided into four groups, including sham group, sham + LTC group, MCAO group, and MCAO + LTC group. Ischemic stroke rats were simulated by middle cerebral artery occlusion (MCAO), and LTC treatment group were orally administrated with 300 mg/kg of LTC once daily for seven consecutive days. LTC therapy was validated in terms of neurobehavioral abnormality evaluation, cerebral infarct area, and histological assessments. The plasma metabolome comparisons amongst different groups were conducted by UHPLC-Q Exactive MS in combination with subsequent multivariate statistical analysis, aiming to finding the molecules in respond to the surgery or LTC treatment. Results: Intragastric administration of LTC significantly decreased not only the neurobehavioral abnormality scores but also the cerebral infarct area of MCAO rats. The interstitial edema, atrophy, and pyknosis of glial and neuronal cells occurred in the infarcted area, core area, and marginal area of cerebral cortex were improved after LTC treatment. A total of 13 potential biomarkers were observed, and Youden index of 11 biomarkers such as LysoPC, SM, and PE were more than 0.7, which were involved in neuroprotective process. The correlation and pathway analysis showed that LTC was beneficial to ischemic stroke rats via regulating glycerophospholipid and sphingolipid metabolism, together with nicotinate and nicotinamide metabolism. Heatmap and ternary analysis indicated the synergistic effect of carbohydrates and lipids may be induced by flavonoid intake from LTC. Conclusion: The present study could provide evidence that metabolomics, as systematic approach, revealed its capacity to evaluate the holistic efficacy of TCM, and investigate the molecular mechanism underlying the clinical treatment of LTC on ischemic stroke.  相似文献   
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