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81.
BACKGROUND: Bone marrow cell injection has been introduced to treat patients with ischemic heart disease. However, focal application of bone marrow cells may generate an arrhythmogenic substrate. OBJECTIVES: To assess the electrophysiological and arrhythmogenic effects of intramyocardial bone marrow cell injection in patients with chronic myocardial ischemia. METHODS: Bone marrow was aspirated in 20 patients (65+/-11 years, 19 male) with drug-refractory angina and myocardial ischemia. Electroanatomical mapping (NOGA, Biosense-Webster, Waterloo, Belgium) was performed during mononuclear cell isolation. Areas for cell injection were selected based on the localization of ischemia on SPECT. These areas were mapped in detail to evaluate local bipolar electrogram duration, amplitude and fragmentation. Mononuclear cells were injected in the ischemic area with the NOGA system. SPECT and electroanatomical mapping were repeated at 3 months. Holter monitoring was repeated at 3 and 6 months. RESULTS: SPECT revealed a decrease in the number of segments with ischemia (3.5+/-2.5 vs. 1.1+/-1.0 at 3 months; P<0.01) and an increased left ventricular ejection fraction (44+/-13% vs. 49+/-17% at 3 months; P=0.02). The number of ventricular premature beats remained unchanged (10+/-24x10(2)/24h vs. 8+/-23x10(2)/24h at 3 months (P=NS) and 12+/-30x10(2)/24h at 6 months (P=NS)). At 3 months follow-up, bone marrow cell injection did not prolong electrogram duration (15.9+/-4.6 ms vs. 15.6+/-4.0 ms; P=NS), decrease electrogram amplitude (3.8+/-1.5 mV vs. 3.8+/-1.5 mV; P=NS), or increase fragmentation (2.0+/-0.5 vs. 1.9+/-0.4; P=NS). CONCLUSION: Intramyocardial bone marrow cell injection does not increase the incidence of ventricular arrhythmias and does not alter the electrophysiological properties of the injected myocardium.  相似文献   
82.
目的探讨骨胶原含量在绝经后骨质疏松症的发生、发展及在骨质疏松性骨折中的作用。方法取7个月龄未交配雌性SD大鼠60只,随机分为四组,A组:对照组(sham组);B组:切除卵巢组;C组:切除卵巢+雌激素治疗组;D组:切除卵巢+降钙素治疗组。除A组外,其他三组通过切除双侧卵巢法12周后制成骨质疏松模型,24周后分别行k的力学特性、右侧股骨三点弯曲试验、羟脯氨酸含量、k骨密度(BMD)测定,Masson三色染色法显示骨胶原形态。结果A、C、D组与B组在k羟脯氨酸含量、BMD、k压缩力学参数值、右侧股骨生物力学参数值、骨胶原染色含量及形态方面差异均有统计学意义(P〈0.05),而A、C、D组之间差异无统计学意义(P〉0.05)。统计学分析显示羟脯氨酸含量与BMD及骨生物力学参数值呈直线相关性。结论骨质疏松的发生与骨胶原含量下降有关。骨胶原含量的下降与BMD降低及骨生物力学改变呈相关性。应用雌激素和降钙素治疗去势后骨质疏松大鼠,不仅可以提高其BMD含量和骨生物力学性能,而且还可以提高骨胶原的含量。  相似文献   
83.
目的 探讨靶心图上心肌灌注缺损区定量分析方法的可靠性、重复性及应用价值。方法 16例急性心肌梗死(AMI)行自体骨髓单个核细胞移植治疗的住院患者,于治疗前、治疗后45和90d行^99Tc^m-MIBI静息心肌灌注显像。在靶心图上勾画缺损区(在左心室靶心图中放射性计数低于40%的区域),并进行定量分析。结果 (1)不同操作者所得ROI结果之间的差异无统计学意义(t=0.52,P〉0.05)。(2)治疗后45d心肌灌注缺损区面积较治疗前缩小34.32%,差异有统计学意义(t=2.83,P〈0.05);治疗后90d心肌灌注缺损区面积较治疗后45d缩小14.77%,差异有统计学意义(t=2.51,P〈0.05)。示自体骨髓单个核细胞移植对缺血心肌的恢复有一定疗效,能够缩小梗死面积,且自体骨髓单个核细胞冠状动脉内移植治疗AMI的疗效在移植后早期(45d内)即有体现。(3)面积百分比是观察心肌灌注变化的重要定量指标。结论 该方法对心肌病变范围及严重程度能准确定量;对评价AMI骨髓于细胞移植术疗效有一定的价值。  相似文献   
84.
自固化磷酸钙人工骨修复骨缺损的临床应用   总被引:5,自引:1,他引:4  
目的:探讨自固化磷酸钙人工骨(CPC)填充修复骨缺损的临床效果。方法:骨缺损94例,男59例,女35例;年龄11~72岁,平均39.4岁。骨缺损部位:胸腰椎38例,跟骨25例,胫骨15例,股骨7例,肱骨近端3例,桡骨远端5例,近节指骨1例。骨缺损原因:骨折塌陷复位后骨缺损63例,骨髓炎20例,骨囊肿6例,骨纤维异常增殖症4例,内生软骨瘤1例。骨缺损范围为1cm×1cm~4cm×20cm,用CPC填充修复,CPC充填量为3~42g,其中单纯CPC填充修复74例(胸腰椎骨折行椎体成形38例,骨折复位后空腔充填25例,良性骨肿瘤病灶刮除后充填11例),载药CPC填充修复骨髓炎20例。结果:所有患者均获随访,随访时间14~48个月,平均29.6个月。全部患者术后未见过敏或毒性反应,无皮疹或高热,血钙、磷、碱性磷酸酶均正常,切口无瘙痒感。随访时X线片显示,植入CPC与宿主骨接触紧密,界面处未见间隙存在,骨缺损处的解剖形状完全或大部分恢复,未见脱落现象,随访时部分患者CPC部分降解成骨。9例发生术后伤口渗出,为淡黄色清亮稀薄分泌物,细菌培养阴性,经换药后伤口愈合良好。结论:CPC填充修复骨缺损安全有效,并发症少,是理想的骨替代品,载药CPC是治疗骨髓炎的理想方法。  相似文献   
85.
The purpose of this study was to investigate the application of intravenous iloprost as a novel therapy for the treatment of post-transplant distal limb syndrome (PTDLS). PTDLS is a benign but disabling complication in the first year after renal transplantation. It is characterized by bilateral, often incapacitating pain in the feet and or knees on motion and a significant rise in alkaline phosphatase levels on laboratory evaluation. On MRI, bone marrow edema of the affected bone regions can be demonstrated. PTDLS differs from steroid induced osteonecrosis of the hip in terms of localization, an average cumulative steroid dosage within expected limits, and a benign outcome, as PTDLS does not progress to overt cell necrosis. From August 2003 to April 2005 we treated 10 patients with MRI-proven diagnosis of PTDLS following a standardized regimen of intravenous iloprost over 5 days. Iloprost led to prompt pain relief measured on a visual analogous scale (VAS) ranging from 1 to 10 (5.6 +/- 1.5 before vs. 2.1 +/- 1.3 after treatment, p = 0.0004). PTDLS represents a benign but disabling complication following renal transplantation. Intravenous iloprost might be a promising therapeutic concept leading to a quick relief of symptoms without relevant side effects.  相似文献   
86.
目的 了解不同的年龄绝经后妇女不同体重质量指数(BMI)与不同部位骨密度(BMD)的关系。方法 来自门诊健康体检的557名绝经后妇女(肝肾等疾病除外),年龄范围50~78岁。用双能X线吸收法(DEXA)测定腰椎(L2-4)、股骨颈、Ward's三角及Troch等部位的BMD,同时计算BMI。根据BMI将研究对象分为3组:低体重组(BMI≤20 kg/m2)、正常体重组(25≥BMI>20 kg/m2)及超重组(BMI>25 kg/m2)。根据年龄又分为3组(50-,60-,70~78岁),用方差分析的方法进行各组间均数的统计学分析。结果不同BMI组总体不同部位的BMD方差分析比较有极显著意义P<0.01,高BMI组的BMD均值明显增高;进一步对同一年龄组不同BMI组的不同部位的BMD均值比较,各组之间均有显著性差异(P<0.01),特别是低体重组的骨密度明显低于其他两组BMI组的BMD。结论BMI与绝经后妇女的骨密度有显著相关,但低体重的绝经后妇女作为骨折的危险人群应受到更多的关注:对于超重的绝经后妇女,通过增加体重的方式增加BMD是危险的,因为超重与高血压、冠心病、糖尿病、心肌梗死及中风有一定的关系;通过其他途径:如年轻时加强运动、多饮牛奶、不盲目减肥等,提高妇女峰值骨含量是非常重要的。  相似文献   
87.
后路椎间融合术治疗成人腰椎滑脱的前瞻性研究   总被引:32,自引:0,他引:32  
目的前瞻性比较采用自体髂骨块和椎间融合器治疗成人腰椎滑脱的效果。方法自1998年2月~2002年2月治疗78例腰椎滑脱患者,所有患者均行椎弓根螺钉固定、后路椎间融合术,根据椎间融合材料的不同,前瞻性将患者随机分为融合器组36例(采用后方斜向单枚椎间融合器)和自体骨组42例(采用自体髂骨块)。男33例,女45例;年龄35~59岁,平均43岁。其中Ⅰ度滑脱29例,Ⅱ度滑脱39例,Ⅲ度滑脱10例。比较两组患者的基本情况、临床效果和影像学结果(融合率和手术节段椎间隙高度的变化)。结果术后随访2年~3年7个月,平均35个月。两组在性别、年龄、滑脱程度、手术时间、失血量以及住院时间上差异无显著性,两组患者均无严重并发症。融合器组优良率为88.8%,自体骨组为83.2%(P=0.99)。术后1年融合器组的融合率为86.1%,自体骨组为83.3%,两组间差异无显著性意义(P=0.87);最终随访时椎间隙高度融合器组平均减少1.7 mm,自体骨组平均减少2.6 mm,两组间差异有非常显著性意义(t=1.38,P< 0.005)。结论采用自体骨为植骨材料者术后椎间隙高度丢失明显增加,但两组之间融合率和临床优良率差异无显著性。椎间融合器和自体髂骨块均可以作为腰椎滑脱后路椎间融合的植骨材料,临床疗效好。  相似文献   
88.
BACKGROUND: Renal fibroblasts are important effector cells in tubulointerstitial fibrosis, with experimental antifibrotic strategies focusing on the functional down-regulation of these cells. Several experimental models of fibrosis have provided evidence for the effectiveness of the polypeptide hormone relaxin as a potential antifibrotic agent. This study was conducted to further elucidate the antifibrotic mechanisms of relaxin on renal fibroblasts in vitro. METHODS: Rat cortical fibroblasts were obtained from outgrowth culture of renal tissue isolated from kidneys 3 days post-unilateral ureteric obstruction and constituted 100% of cells studied. A relaxin radio-receptor assay was used to establish binding of relaxin to renal fibroblasts in vitro. Functional studies then examined the effects of H2 relaxin (0, 1, 10 and 100 ng/ml) on fibroblast kinetics, expression of alpha-smooth muscle actin (alpha-SMA), total collagen synthesis, collagenase production and collagen-I lattice contraction. CTGF mRNA expression was also measured by northern analysis. RESULTS: H2 relaxin bound with high affinity to rat renal fibroblasts, but receptor numbers were low. Consistent with its previously reported bimodal effect, transforming growth factor (TGF-beta 1) reduced fibroblast proliferation, an effect abrogated by H2 relaxin. Fibroblasts exposed to H2 relaxin (100 ng/ml) for 24 h demonstrated decreased immunostaining for alpha-SMA and reduced alpha-SMA protein expression compared with controls. There was a trend for a relaxin-mediated reduction in total collagen synthesis and alpha 1(I) mRNA expression with large dose-related increases in collagenase protein expression being observed. TGF-beta 1-stimulated collagen-I lattice contraction was significantly inhibited following co-incubation with 100 ng/ml relaxin. Incremental doses of H2 relaxin had no significant effect on CTGF mRNA expression. CONCLUSIONS: The findings of this study suggest that the antifibrotic effects of relaxin involve down-regulation of fibroblast activity, increase in collagenase synthesis and restructuring of collagen-I lattices, which are consistent with its known physiological role of matrix remodelling. Although there appears to be an interaction between TGF-beta 1 and H2 relaxin, this does not appear to involve a reduction in CTGF mRNA expression.  相似文献   
89.
The aim of this study was to clarify and compare the temporal course of bone mineral density (BMD) between fast bone losers and normal residents in Miyama Village, a rural Japanese community. BMD was measured over a 10-year period in a cohort study in Miyama Village, Wakayama Prefecture, Japan, to provide information on rate of bone loss in the mature and elderly population. Subjects (n=400) were selected by sex and age stratum from the full list of residents born in 1910–1949, with 50 men and 50 women in each age decade. Baseline BMD of the lumbar spine and proximal femur was measured using dual energy X-ray absorptiometry in 1990, 1993, 1997 and 2000. In the cohort, 171 men and 189 women completed the follow-up survey performed in 1993. After calculating the rate of bone loss between 1990 and 1993, the greatest tertile from the distribution of bone loss was categorized as fast bone losers, with the remainder considered as normal subjects. Changes in BMD were compared between normal subjects and fast bone losers over the 10-year period. Mean rate of change for BMD at both lumbar spine and femoral neck in fast bone losers recovered to levels similar to those in normal subjects over 7 years of observation. By contrast, BMD at the lumbar spine and femoral neck decreased steeply over the 10-year period in both groups, and mean BMD for fast bone losers was significantly lower than that of normal subjects (P<0.05). These differences were apparent only at the lumbar spine in both men and women, even after adjusting for age. These results indicate that fast bone loss is a transient phenomenon rather than a fixed status, although individuals who have been categorized as fast bone losers at some stage continue to display low BMD in the lumbar spine.  相似文献   
90.
目的观察应用动力髁螺钉联合骨肽注射液治疗股骨髁上骨不连的疗效。方法53例股骨髁上骨不连患者随机分为两组:对照组(26例)和治疗组(27例),两组均应用动力髁螺钉治疗,治疗组加用骨肽注射液治疗。随访,进行疗效评价,记录骨愈合时间和测定疼痛指数。结果治疗组疗效优于对照组。结论应用动力髁螺钉联合骨肽注射液治疗股骨髁上骨不连可提高疗效。  相似文献   
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