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41.
目的:经胸超声心动图指导下应用国产Amplatzer封堵器介入治疗先天性心脏病,分析其应用价值。方法:选择2005-05/2007-03在成都市第三人民医院应用国产Amplatzer封堵器进行介入治疗的先天性心脏病患者59例,其中膜周型室间隔缺损30例,继发房间隔缺损15例,动脉导管未闭14例,所有患者均知情同意。①所有Amplatzer封堵器均由北京形状记忆合金材料有限公司提供。仪器采用Sequoia256及Sequoia512型彩色多普勒诊断仪,探头频率为2.5~5.0MHz。②在经胸超声心动图及X射线的引导下采用国产封堵器行先天性心脏病介入封堵术,术后1d,7d、1个月、3个月、1年随访,观察封堵器的位置,有无残余分流。结果:59例患者均封堵成功,全部进入结果分析,无脱落。2例膜周型室间隔缺损患者微量残余分流在术后3个月完全消失;其余患者均未见封堵器脱落、移位,无溶血、房室传导阻滞、瓣膜反流、心脏穿孔等严重并发症。结论:经胸超声心动图可用于引导先天性心脏病的封堵器介入治疗,同时也可用于术后随访,观察封堵器封堵后的移位、脱落等物理学变化。  相似文献   
42.
瘢痕疙瘩家系Fas基因的突变:2个家系10份标本分析   总被引:1,自引:0,他引:1  
目的:观察瘢痕疙瘩家系样本中Fas基因有无突变,探讨Fas基因突变在瘢痕疙瘩形成中的意义。方法:实验于2005-01/05在上海基康公司完成。①标本来自南方医科大学南方医院整形外科2005年收集的A和B两个瘢痕疙瘩家系,所有参与观察的家系成员均签署知情同意书。②采用聚合酶链反应及基因测序技术,分别以A家系两例患者的瘢痕疙瘩组织为观察对象,以其周围正常皮肤及外周静脉血作为自身对照;其配偶的外周静脉血作为正常对照。并以B家系中两例患者的外周静脉血作为不同家系间的对照。共取10份样本,4份组织样本,6份静脉血标本。检测10份样本中Fas基因外显子1~9的基因序列。结果:①基因测序发现所检测的10个瘢痕疙瘩家系标本Fas基因的1~8外显子均未发现突变。②2份瘢痕疙瘩组织标本在第9外显子编码区的11bp,53bp两个位点上存在单个碱基的基因突变或多态性改变。结论:瘢痕疙瘩Fas基因外显子9区段的基因结构异常极有可能造成Fas蛋白的功能改变,从而导致身体局部瘢痕疙瘩的形成。  相似文献   
43.
目的:分析跟骨定量超声骨质测量中各参数与骨密度及形态计量学指标的相关性。方法:选择2004-01/2005-12广州市第六人民医院和中山大学三院骨科小腿以上截肢患者38例,将其跟骨定量超声测定的超声振幅衰减平均值与健康青年人骨峰值进行比较,>-2.5 SD者为骨量正常组(12例),<-2.5 SD者为骨质疏松组(26例)。分别进行跟骨定量超声、双能X线骨密度测量仪及骨形态计量学测量,应用直线相关分析法分析跟骨定量超声测定中各参数与骨密度及骨组织形态计量学各指标的相关性。结果:38例全部进入结果分析。①骨质疏松组跟骨超声振幅衰减平均值和骨硬度指数值均小于骨量正常组(P<0.01)。②骨量正常组跟骨骨密度值显著高于骨质疏松组[(352±16),(233±14)mg/cm2,P<0.01]。③骨量正常组跟骨平均骨小梁间距或弥散度低于骨质疏松组而松质骨体积高于骨质疏松组(P<0.05)。④超声振幅衰减平均值和骨硬度指数与骨密度呈直线正相关(r=0.814,0.326,P<0.01,0.05)。⑤超声传播速度与骨小梁游离末端、平均骨小梁间距呈直线负相关(r=-0.688,-0.712,P<0.01),与小梁间连点数、松质骨体积呈直线正相关(r=0.672,0.794,P<0.01);骨硬度指数与平均骨小梁间距呈直线负相关(r=-0.358,P<0.05),与松质骨体积呈直线正相关(r=0.513,P<0.01)。结论:跟骨定量超声测量中,超声振幅衰减平均值能较好地反映骨的密度,超声传播速度能较好地反映骨的质量,而骨硬度指数能较综合地反映骨强度的改变。  相似文献   
44.
目的:已有研究证实,活血化瘀中药可对抗激素的作用,对激素性股骨头缺血性坏死早期有明显的防治作用。观察桃红四物汤对激素性股骨头缺血性坏死碱性成纤维细胞生长因子表达的影响,进一步阐明活血化瘀法防治激素性股骨头缺血性坏死的机制。方法:实验于2005-04/2006-10在福建中医学院中心实验室完成。①实验材料:健康成年新西兰大白兔60只,雌雄各半,体质量1.8~2.2kg,清洁级,由福建中医学院实验动物中心购自上海市松江区松联实验动物场。桃红四物汤的组成成分为:桃仁、红花、熟地、当归、白芍、川芎。②实验方法:60只健康成年新西兰大白兔,随机分为正常组6只和实验组54只。实验组采用贺氏造模法建立股骨头缺血坏死模型,6周后处死正常组和实验组各6只,确定造模成功。将造模剩余动物随机分为中药治疗组和激素对照组,每组21只:中药治疗组以桃红四物汤7mL/kg(浓度为0.75g/mL)灌胃治疗,1次/d,激素对照组以生理盐水7mL/kg灌胃治疗,1次/d。③实验评估:于治疗后1,2,4周进行股骨头组织病理学观察,并采用放射免疫法检测血清碱性成纤维细胞生长因子含量变化。结果:纳入新西兰大白兔60只,实验过程中因心脏、脑血管梗死死亡18只,进入结果分析42只。桃红四物汤灌胃治疗1,2,4周后,中药治疗组股骨头局部空骨陷窝数明显减少,与激素对照组比较,差异有显著性意义(P<0.05),中药治疗组碱性成纤维细胞生长因子表达增强,与激素对照组相比,差异有显著性意义(P<0.01)。结论:桃红四物汤能促进激素性股骨头缺血性坏死模型兔体内碱性成纤维细胞生长因子的表达,明显减少股骨头局部空骨陷窝数,促进坏死股骨头的修复,这可能是活血化瘀法防治激素性股骨头缺血性坏死的机制之一。  相似文献   
45.
Expression of bcl-xL can confer a multidrug resistance phenotype   总被引:14,自引:3,他引:14  
Minn  AJ; Rudin  CM; Boise  LH; Thompson  CB 《Blood》1995,86(5):1903-1910
It has been suggested that genes that regulate apoptotic cell death may play an important role in determining the sensitivity of tumor cells to chemotherapy. We have recently cloned a member of the bcl-2 family, bcl- x. To test whether bcl-XL expression affects the sensitivity of tumor cells to chemotherapy, we have created stable cell lines overexpressing bcl-XL and have tested these cells for resistance to cell death induced by metabolic inhibitors and chemotherapeutic agents. Bcl-XL expression dramatically reduces the cytotoxicity of bleomycin, cisplatin, etoposide, vincristine, hygromycin B, and mycophenolic acid for up to 4 days in culture. Bcl-XL does not prevent cells from undergoing cell cycle arrest in response to these drugs, but rather prevents treated cells from undergoing apoptosis. Cell-cycle analysis on cells treated with the chemotherapeutic agents bleomycin, cisplatin, etoposide, and vincristine, show that the drugs cause growth arrest in different positions within the cell cycle. Bcl-XL expressing cells treated with chemotherapeutic drugs retain their proliferative ability after the drugs are removed. Interestingly, vincristine-treated cells expressing bcl-XL become polyploid after drug removal. These data show that bcl-XL protects cells from a wide variety of apoptotic stimuli, acts in multiple positions within the cell cycle, and confers a multidrug resistance phenotype. The ability of bcl-XL to prevent apoptotic cell death in response to chemotherapy-induced DNA damage and cell-cycle arrest may contribute to the accumulation of chromosomal aberrations within tumors. The expression of bcl-XL in tumor cells is likely to be an important indicator of chemotherapeutic efficacy.  相似文献   
46.
Brown  CB; Beaudry  P; Laing  TD; Shoemaker  S; Kaushansky  K 《Blood》1995,85(6):1488-1495
We have cloned, expressed, and partially purified a naturally occurring, truncated, soluble form of the human granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor alpha subunit to investigate its biochemical and biologic properties. The soluble receptor species lacks the transmembrane and cytoplasmic domains that are presumably removed from the intact receptor cDNA by a mechanism of alternative splicing. The resulting soluble 55- to 60-kD glycosylated receptor species binds GM-CSF with a dissociation constant (kd) of 3.8 nmol/L. The soluble GM-CSF receptor successfully competes for GM-CSF binding not only with the transmembrane-anchored GM-CSF receptor alpha subunit but also with the native oligomeric high-affinity receptor complex. In addition, in human bone marrow colony-forming assays, the soluble GM-CSF receptor species can antagonize the activity of GM-CSF. Our data suggest that the soluble GM-CSF receptor may be capable of acting in vivo as a modulator of the biologic activity of GM-CSF.  相似文献   
47.
Platelet activating factor (PAF) and thromboxane A2 (TxA2) are two vasoactive mediators which can decrease renal blood flow. Both are synthesized by various intrarenal cell types or by macrophages which may infiltrate the kidney during unilateral ureteral obstruction (UUO). In several experimental systems, PAF receptor activation is accompanied by TxA2 release; pharmacological modification of TxA2 synthesis or receptor activation modulates the response to PAF. The involvement of PAF in UUO has not been studied previously, and the role of TxA2 has not been clearly defined by previous investigations. The hemodynamic response to acute UUO is characterized by decreases in renal blood flow (RBF) and glomerular filtration rate and an acute increase in ureteral pressure. In the present experiments, the involvement of either PAF or TxA2 in the acute response to UUO was studied by determining if blockade of either the TxA2 or PAF receptor would affect the renal hemodynamic response to UUO. In addition, the effect of blockade of the TxA2 receptor on the renal response to PAF was determined. Our results indicate that only a small portion of the renal response to PAF is mediated by TxA2, and that neither PAF nor TxA2 can be implicated in the acute hemodynamic response to UUO. TxA2 or PAF involvement in the chronic response to UUO still remains to be determined.  相似文献   
48.
磁性明胶微球体内分布实验研究   总被引:11,自引:0,他引:11  
对磁性明胶微球进行了同位素标记。用γ-闪烁照相技术观察了磁性明胶微球在兔体内的分布。结果表明:靶部位的放射活性加磁场是未加磁场的15倍,而且施加磁场时间长和磁场强度大有利于磁性明胶微球定位于靶区。文中也介绍了自行设计的外加磁场装置。  相似文献   
49.
BACKGROUND: Osteopenia with decreased bone mineral density (BMD) is a frequent finding in renal allograft recipients. Data concerning the bone architecture in these patients do not exist, however. METHODS: We compared the bone architecture of 33 randomly assigned women (age 49 +/- 12 years), who had received renal allografts 5.6 +/- 5.3 years before the investigation, with 74 women (age 50 +/- 14 years) who were admitted for osteodensitometry. All patients underwent single-energy computed tomography (SEQCT) and a midvertebral high-resolution tomography with computer-assisted analysis of the trabecular vertebral body architecture. RESULTS: Progressive alteration of bone architecture was associated with increasing vertebral height loss of the vertebral body. Height reduction of a vertebral body of more than 15% was associated with a significantly lower BMD (-2.3 +/- 0.8 versus -1.1 +/- 1.1 standard deviations below normal BMD), a lower trabecular bone area (13 +/- 8% versus 42 +/- 22%) and a lower trabecular diameter (1.4 +/- 0.5 mm versus 2.2 +/- 0.8 mm) compared to recipients without height reduction. In comparison to a matched group of patients with similarly reduced BMD (1.1 +/- 1.2 versus 1.2 +/- 1.1 SD below normal BMD), renal allograft recipients showed a lower number of trabecular plates (5.6 +/- 3.1 versus 7.0 +/- 3.7) and a smaller intertrabecular surface (54 +/- 116 mm versus 75 +/- 138 mm). CONCLUSIONS: Alterations of bone architecture in renal allograft recipients were associated with progressive vertebral height loss. Despite similar bone mineral density, differences of bone architecture could be observed between renal allograft recipients and patients with osteoporosis.   相似文献   
50.
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