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31.
8kg以下婴儿室间隔缺损伴肺动脉高压手术治疗   总被引:25,自引:0,他引:25  
为提高小婴儿室缺伴肺动脉高压的手术疗效,总结16例8kg以下室间隔缺损(室缺)伴肺动脉高压婴儿行急诊手术修补室缺的经验。其中14例在深低温停循环下进行,手术效果满意;术后死亡1例(6%)。作者认为,婴儿巨型室缺应尽早手术治疗为宜,深低温停循环方法尤为适合;术后强调持续保持病婴镇静及呼吸道通畅,防止肺高压危象的发生。  相似文献   
32.
用脉冲式多普勒超声心电图对51例糖尿病患者的左室舒张功能参数进行了测定.与正常对照组结果相比,糖尿病患者的左室舒张早晚期最大流速之比、快速充盈分数、快速充盈减速度及左室舒张早期最大流速显著降低,而左室舒张晚期最大流速显著增高.在糖尿病患者中,有视网膜病变组与无视网膜病变组相比,左室舒张早晚期最大流速之比、快速充盈分数及快速充盈加速度显著降低,而左室舒张晚期最大流速显著增高.提示糖尿病患者左室舒张功能受损.  相似文献   
33.
高血压大鼠心肌中MMP-2的蛋白表达及其RAS阻断后的变化   总被引:4,自引:2,他引:2  
[目的]探讨高血压大鼠左室心肌中基质金属蛋白酶-2(MMP-2)蛋白表达的变化以及血管紧张素转化酶抑制剂(ACEI)、血管紧张素Ⅱ1型受体拮抗剂(AT1-ant)单独与联合治疗对高血压大鼠心肌中MMP-2蛋白表达的影响。[方法]40只雄性8周龄的易卒中自发性高血压大鼠(SHRSP)随机分成5组:SHRSP对照组、安慰剂组、缬沙坦组、苯那普利组及缬沙坦与苯那普利联用组。另外,取8只雄性8周龄的京都Wistar大鼠(WKY)作为对照。利用免疫组织化学的方法检测WKY以及SHRSP左室心肌中MMP-2蛋白的表达。[结果]SHRSP的收缩压(SBP)、左室质量指数(LVMI)、胶原容积分数(CVF)、血管周围胶原面积(PVCA)、左室心肌MMP-2蛋白表达较同龄的WKY显著增高。给予苯那普利、缬沙坦单独或联合治疗后SHRSP的LVMI、CVF、PVCA、左室心肌 MMP-2蛋白表达都显著降低。苯那普利、缬沙坦单独应用时的效果没有差异,而联合应用的效果更显著。[结论]SHRSP左室心肌中MMP-2蛋白表达增高,肾素血管紧张素系统(RAS)阻断后MMP-2蛋白表达显著减少;苯那普利、缬沙坦逆转高血压心室重塑的作用可能部分通过下调MMP-2蛋白表达而实现;苯那普利和缬沙坦都能降低SHRSP的血压以及逆转其左室重塑,而联合用药的作用更显著。  相似文献   
34.
Objective To investigate the changes of perioperative right ventricular function after pulmonary resction. Methods 45 cases of pulmonary resection were divided into four groups.Group Ⅰwas wedge resection(n = 10), GroupⅡ was lobectomy(n = 19), Group Ⅲ was double lobectomy(n=7)and Group Ⅳ was pneumonectomy(n=9). The changes of CVP, PAMP, PEP/ET, Sa, VTIs, RVSP, Ea/Aa, and Tel were evaluated by traditional ultrasonic and tissue Doppler ultrasonic techniques at different time inter- vals (pre-operation, 5-7 days orland 1 month post-operation), Results Compared with the pre-operation CVP, the indexes of all groups have no significant changes post-operatively. Wedge resection didn' t obviously influence right cardiac after load and systolic function/diastolic function. No evidet changes detected in Tei pre-and post-operatively. However, the indexes (PAMP, RVSP and PEP/ET ratio) reflecting right cardiac afterload evidently increased at post-pneumonectomy or lobectomy group5- 7 days post-opera- tive. All these reflect the decrease of Tei, which was more obvious in pneumonectomy than in lobectomy group. Right cardiac after- load, systolic/diastolic function and Tel index recovered to pre-operative level 1 month post-operation in single lobectomy group. But the above indicators, especially the Tel, were still high in double lobectomy and pmeunonectomy groups 1 morth post-operation.Tei index is positively correlated with PAMP and is weakly correlated with PET/ET ratio and Ea/Aa ratio. Conclusion Pulmonary wedge resection doesn't evidently influence right cardiac function. However, right cardiac diastolic function evidently decreases temporarily at lobectomy group. The systolic function and diastolic funetions decrease after double-lobectomy and pneumonectomy and it's more evident in pneumonectomy group. Though the right cardiac afterloads of lobectomy, double lobectomy and pneumonectomy groupa all increase significantly post-operativlye, only the former recover to pre-operative level 1 month after surgery.  相似文献   
35.
徐育红  王建安 《浙江医学》2004,26(6):407-409
目的探讨原发性高血压(EH)患者微量白蛋白尿(MCA)与血压及左室重塑的关系.方法 84名EH患者按24h尿微量白蛋白值分为微量白蛋白尿组(MCA组)和正常白蛋白尿组(NMCA组),进行动态血压、心脏超声检测,比较两组动态血压值、左室重量指数(LVMI)及左室重塑的特点.结果 MCA组平均收缩压、平均舒张压、脉压、平均动脉压均高于NMCA组(均P<0.01);MCA组LVMI、左室肥厚与向心性肥厚的发生率均高于NMCA组(均P<0.01),正常构型率低于NMCA组(P=0.01).LVMI与尿微量白蛋白值、平均收缩压、平均舒张压均呈显著的正相关(均P<0.05).结论合并有MCA的EH患者血压较高,LVMI较大,左室肥厚与向心性肥厚的发生率较高.MCA与血压及左室重塑密切相关.  相似文献   
36.
急性心肌梗死后室间隔穿孔患者的外科治疗   总被引:1,自引:0,他引:1  
目的:探讨急性心肌梗死(AMI)后室间隔穿孔(VSR)的外科治疗方法和结果。方法:回顾分析手术治疗的8例急性心肌梗死后室间隔穿孔患者的临床资料。男性7例,女性1例,年龄62~74岁,平均年龄67.5岁,均有急性心肌梗死史,4例有高血压病史,2例有糖尿病史,6例合并室壁瘤。心功能NYHAⅢ级6例,Ⅳ级2例。术前射血分数(EF)值33%~71%,平均54.5%。患者心肌梗死至手术的间隔时间平均为5.4周。所有患者均采用牛心包补片旷置室间隔穿孔,7例患者同期行冠状动脉旁路移植术,平均2.7支/例。结果:手术死亡2例,死亡率25%。其中1例因多脏器功能衰竭于术后32 d死亡,另1例因肾功能不全于术后6 d死亡。存活6例随访3~24个月,平均13.2个月,无晚期死亡,无心血管事件。心功能NYHAⅠ级5例,Ⅱ级1例。术后EF值50%~66%,平均58.3%。结论:掌握适当的手术时机、完善的术前准备、积极的围手术期治疗、准确的手术操作和避免术后并发症的发生,能有效地降低急性心肌梗死后室间隔穿孔患者的死亡率,改善其预后。  相似文献   
37.
连续浅缝法修补膜周型室间隔缺损   总被引:4,自引:0,他引:4  
目的探讨连续浅缝法修补单纯膜周型室间隔缺损(pVSD)法的效果。方法选取2002年1月至2004年10月我院收治的体重10kg以内(≤10kg)50例单纯膜周型室间隔缺损患者,均采用自体心包连续浅缝法修补。结果主动脉阻断时间32±21min(14-52min),体外循环时间56±35min(29-69min)。无°房室传导阻滞发生,9例发生右束支传导阻滞,2例结性心律。2例膜周偏流出道型VSD患者因前上缘残余分流分别为0.4cm和0.3cm,再次手术修补;1例后下缘残留细束样分流,直径0.15cm,随访6个月后自愈;10例膜周偏流出道型VSD患者剪开三尖瓣,8例垂直瓣环,2例平行瓣环;1例三尖瓣中度反流,随访无加重;5例轻度反流,4例轻微反流,随访均无加重;1例心包积液;1例再次进入手术室止血。结论连续浅缝法是修补单纯膜周型室间隔缺损的有效外科纠治方法。  相似文献   
38.
Biomechanics     
Therapeutic agents used to treat osteoporosis reduce the incidence of vertebral and nonvertebral fractures in osteoporotic women. The antiremodeling agents, such as the bisphosphonates, prevent bone loss by suppressing the remodeling rate, perhaps increasing bone volume slightly, and increasing mineralization of the tissue. The anabolic agents, of which rhPTH(1–34) is the only one approved, accomplish this in a manner that is almost completely the opposite in terms of biological process. rhPTH(1–34) causes net bone gain by stimulating both modeling and remodeling, by increasing bone volume significantly through direct bone apposition to trabecular and endocortical surfaces, and by reducing the mean degree of tissue mineralization (a natural consequence of enhanced remodeling). Each of these treatments maintains or increases bone strength and is similarly effective at preventing fractures. However, because of their different mode of action, each has different consequences for bone matrix quality (defined here by microdamage accumulation and by the properties of mineral and collagen) and the mechanical properties of the tissue. Although bone's composite nature makes it a relatively tough material—more like fiberglass than glass—the accumulation of damage will nevertheless reduce its residual mechanical properties until the damage is repaired through remodeling. Agents that suppress remodeling are associated with both microdamage accumulation and increased mineralization. The biological importance of damage and mineralization to bone's mechanical properties is still a source of debate.  相似文献   
39.
Abstract:  We describe a patient with acquired alpha-thalassemia myelodysplastic syndrome (ATMDS). A previously healthy 66-year-old man presented with hemoglobin of 9.3 g/dL, mean corpuscular volume 59 fL, and a bone marrow aspirate with increased erythroid precursors and hypolobulated megakaryocytes. Hemoglobin H inclusions were seen in most red cells after 1% brilliant cresyl blue supravital stain of the peripheral blood. At the molecular level, we identified of a novel mutation in the most 3' exon of the ATRX gene ( C GA→ T GA substitution in codon 2407) resulting in a premature termination codon (p.R2407X). This case provides further evidence for a link between ATRX mutations and ATMDS, and suggests a possible role for the conserved Q-box element in ATRX function.  相似文献   
40.
Background Although there have been reports dealing with ventricular diverticulum (VD) analyzed by cisternography and computed tomography (CT), those focusing on magnetic resonance imaging (MRI) or neuroendoscopic findings are rare. Case report We present a case of noncommunicating hydrocephalus caused by aqueductal stenosis with cystic lesion located in supracerebellar region. Third ventriculostomy was performed on this case. The conventional CT and MRI were compatible with usual VD, but neuroendoscopic examination suggested otherwise. The endoscopic view inside of the cystic lesion demonstrated passing veins and no membrane. We diagnosed this cystic lesion as a unique subtype of advanced VD mimicking spontaneous ventriculostomy. Endoscopic observation of the cyst was very useful for accurate diagnosis and safe treatment.  相似文献   
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