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81.
82.
全主动脉弓替换术中顺行性脑灌注时血流变化观察 总被引:5,自引:2,他引:3
目的 利用前瞻性随机对照方法比较全主动脉弓替换术中单侧顺行性脑灌注 (ASCP)和双侧ASCP时视网膜中央动脉、球后血管血流变化和血S1 0 0蛋白浓度变化。方法 1 6例全主动脉弓替换术患者随机分为单侧AS CP和双侧ASCP组 ,每组各 8例。两组均行术前术后颅脑计算机体层摄影 (CT)。术中采用经眼球超声监测视网膜中央动脉及球后血管血流。术中术后动态测定血S1 0 0蛋白浓度。结果 两组各有 1例出现短暂性神经功能异常。ASCP过程中单侧组右侧视网膜中央动脉可探及血流 ,左侧视网膜中央动脉不可探及 ,双侧组两侧视网膜中央动脉均可探及血流。所有患者球后动脉均可探及血流。两组间各阶段血S1 0 0蛋白浓度无显著性差异 (P >0 .0 5 )。结论 在基底动脉环完整 ,存在有效侧支循环条件下 ,单侧灌注操作较为简便 ,双侧灌注在ASCP期间两侧脑灌注较为均衡 ,但两种灌注方法对S1 0 0蛋白浓度的影响无显著性差异。 相似文献
83.
OBJECTIVE: To compare the outcome of urgent haemorrhoidectomy with conservative treatment for prolapsed thrombosed internal haemorrhoids. METHODS: A prospective randomised study of 50 patients with prolapsed thrombosed internal haemorrhoids was carried out using clinical and ultrasonic outcome measures. Peri-operative bed occupancy and the presence of symptoms at 6 and 24 months were compared. Endoanal ultrasonic scanning was carried out to investigate anal sphincter integrity in those patients willing to be studied. RESULTS: The median length of hospital stay for the group treated conservatively; 2 nights (range 1-9 nights) was significantly shorter than for the group treated by urgent haemorrhoidectomy; 4 nights (range 1-12 nights, P < 0.01). There was no difference between treatment groups in the number of patients with symptoms at six or 24 months. Urgent haemorrhoidectomy was associated with a significantly higher incidence of endosonographically detected anal sphincter damage in 18 patients: 66%vs 0% (P = 0.009). CONCLUSION: Conservative treatment for prolapsed thrombosed internal haemorrhoids is associated with shorter in patient stay and less anal sphincter damage compared with operative treatment. 相似文献
84.
Christina Djokoto George Tomlinson Stephen Waldman Marc Grynpas Angela M. Cheung 《Journal of clinical densitometry》2004,7(4):448-456
Dual-energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) are the accepted modalities for the evaluation of fracture risk in the clinical setting. However, neither method provides a direct measurement of bone mechanics. In this study, we investigated a prototype device, known as a mechanical response tissue analyzer (MRTA), which provides direct mechanical measurements of mechanical properties of bone. A total of 56 healthy volunteers (20 men and 36 women) between the ages of 18 and 83 were recruited. The MRTA was used to measure the cross-sectional bending stiffness (EI) of the ulna bone. Axial speed of sound (SOS) at the ulna bone was determined by QUS; bone mineral content (BMC) and bone mineral density (BMD) were determined by DXA. Correlations, regression analysis, and analyses of variance (ANOVAs) were used to compare the three modalities. These analyses revealed that although there are strong linear relationships among the data collected by the various technologies, the bone properties reflected by MRTA are not fully explained by DXA and QUS. We conclude that the total information conveyed by MRTA measurements is unique. Further research is needed to delineate the different qualities of bone strength that are captured by MRTA, but not by DXA or QUS. 相似文献
85.
妊马雌酮对绝经后妇女心血管功能的影响 总被引:1,自引:0,他引:1
目的:探讨妊马雌酮替代疗法对绝经妇女心脏和周围血管功能的影响。方法:随机选择22例有更年期症状的绝经妇女(20例自然绝经,2例子宫切除),采用多普勒超声测定妊马雌酮治疗前后心血管轿流动力学参数,统计学分析采用配对t检验。结果:服用后左心室收缩末期容积减小,射血分散和短轴缩短率增高,治疗前后差异显性意义;左心室舒张功能差异无显性意义。左颈内动脉、左大脑中动脉和左视网膜中动脉舒张期最小流速增大,搏动指数和阻力指数减小。结论:妊马雌酮可改善绝经妇女的心脏功能,降低周围血管阻力。 相似文献
86.
目的 通过与血管内超声 ( IVUS)相比较 ,探讨压力导丝在评价冠脉内支架置入即刻效果 ,指导优化支架置入中的作用。方法 5 1例患者置入冠脉内支架后先后予血管内超声和压力导丝检测判断是否达到相应的理想支架置入标准。若未达标准 ,则进一步采用更高压力同样球囊或更大球囊再扩张。结果 支架置入后 IVUS判断 3 1例达到标准 ,不需再扩张 ,15例不满意者再扩张支架 ,支架内截面积增加 2 4 .3 % ( P<0 .0 5 ) ,最终 4 1例 ( 89% )得到满意 IVUS,5例因超声导管未跨过支架无超声资料 ;压力导丝检测 3 5例达到标准 ,不需再扩张 ,16例不满意者再扩张支架最终 4 5例 ( 88% )得到满意结果 (心肌部分血流储备 ,FFRmyo>0 .90 )。血管内超声和压力导丝两者在判定理想支架置入方面有很好的相关性 ,符合率达 90 %。以血管内超声检测作金标准 ,应用受试者工作特性曲线 ( ROC)计算心肌部分血流储备 FFRmyo预测理想支架置入的最佳临界点为 0 .90。结论 压力导丝是指导冠脉支架置入更方便、安全的有效手段 ,有广泛推广应用的价值 相似文献
87.
K. H. Vogelberg M. Mühl M. Köhler 《Journal of molecular medicine (Berlin, Germany)》1987,65(15):713-718
Summary Seventy-five diabetic and 40 nondiabetic subjects who where suffering from peripheral vascular disease were studied in order to determine whether the degree of the severity of their disease can be better calculated by Doppler ultrasound examinations of the peak velocity than by the systolic pressure of the peripheral bloodstream. In 46 examinations of normal controls the mean value of the peak velocity was 13.3±3.3 cm/s with a standard deviation of 15.4%±13.2% on one day and 16.1%±15.9% on different days. Considering patients with or without diabetes mellitus the velocity was significantly decreased in correlation to an increasing degree of severity of the vascular disease (P<0.001); however, the decrease was lower in diabetic than in nondiabetic subjects (6.9±2.8 vs 4.6±6.2,P<0.05). The systolic pressure hardly decreased, but remained higher in all stages of peripheral vascular disease of diabetics than in the nondiabetic subject (P<0.05 toP<0.005). There was a significant decrease of the systolic pressure only in diabetic subjects with the most advanced degree of the disease, i.e. stage IV (P<0.05).It is concluded from this study that Doppler ultrasound measurements of the peak velocity of the peripheral bloodstream are a useful parameter to calculate the degree of severity of the peripheral vascular disease. In addition, it is concluded than peak velocity is an even better prognostic indicator of peripheral vascular disease than is measurement of the systolic blood pressure at the feet.
Abkürzungen AVK periphere arterielle Verschlußkrankheit - USDI Ultraschall-Doppler-Index - MSBG maximale Blutströmungsgeschwindigkeit - HFV Herzfrequenzvariation 相似文献
Abkürzungen AVK periphere arterielle Verschlußkrankheit - USDI Ultraschall-Doppler-Index - MSBG maximale Blutströmungsgeschwindigkeit - HFV Herzfrequenzvariation 相似文献
88.
89.
Luciano Potena Francesco Grigioni Gaia Magnani Paolo Ortolani Fabio Coccolo Simonetta Sassi Koen Koessels Cinzia Marrozzini Antonio Marzocchi Samuela Carigi Anna C. Musuraca Antonio Russo Carlo Magelli Angelo Branzi 《American journal of transplantation》2005,5(9):2258-2264
Although observational studies suggest that hyperhomocysteinemia may be a risk factor for coronary allograft vasculopathy (CAV), prospective data on homocysteine-lowering interventions and CAV development are lacking. We, therefore, randomized 44 de novo heart transplant (HT) recipients to 15 mg/day of 5-methyl-tetrahydrofolate (n=22), or standard therapy (control group, n=22) to investigate the effect of homocysteine lowering on the change in coronary intimal hyperplasia during the first 12 months after transplant, as detected by intra-vascular ultrasound (IVUS). Although 12 months after HT, homocysteinemia was lower in folate-treated patients (p<0.001), coronary intimal area increased similarly in the two groups (p>0.4). Conversely, hypercholesterolemia and cytomegalovirus infection were both associated with increased intimal hyperplasia (p<0.04), independently from folate intake. Sub-group analysis revealed that folate therapy reduced intimal hyperplasia in patients with hyperhomocysteinemia before randomization (n=19; p=0.02), but increased intimal hyperplasia in patients with normal homocysteine plasma concentrations (p=0.02). This bimodal effect of folate therapy persisted significantly after adjusting for cytomegalovirus infection and hypercholesterolemia. Despite effective in prevent hyperhomocysteinemia after heart transplantation, folate therapy does not seem to affect early CAV onset. However, sub-group analysis suggests that folate therapy may delay CAV development only in patients with baseline hyperhomocysteinemia, while may favor CAV progression in recipients with normal baseline homocysteinemia. 相似文献
90.
目的评价螺内酯联合依那普利治疗老年人扩张型心肌病(DCM)心力衰竭的有效性和安全性。方法以148例老年DCM心力衰竭患者作研究对象,按随机化原则分为观察组(74例)和对照组(74例)。对照组为依那普利,加上基础用药(地高辛、双氢克尿噻);观察组为对照组用药加上螺内酯。治疗6周后复查两组的动态心电图、超声心动图。结果治疗后两组的左室射血分数(LVEF)均有增加,左室收缩末期容积(LVESV)和左室舒张末期容积(LVEDV)均有减少,24 h室性早搏(VA)数也均有减少;观察组与对照组比较,LVEF显著增加。两组均未发现高血钾及肝肾功能损害。结论在老年DCM心力衰竭常规用药的基础上,常规加用螺内酯联合依那普利的治疗有效、安全,可显著改善左室重构和防治猝死。 相似文献