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11.
BACKGROUND: The effect of mitral valve morphology (MVM) on the long-term results of mitral balloon valvuloplasty (MBV) is not well established. The aim of the study was to evaluate the impact of MVM on long-term outcome of MBV. METHODS: Five hundred and eighteen consecutive patients (mean age, 31+/-11 years) who underwent successful MBV were followed up for 0.5-16.5 (mean, 6+/-4.5) years. Patients were divided into two groups according to their mitral echo score (MES) before MBV: group A (n=340; MES8). RESULTS: We report the immediate and long-term clinical and echocardiographic results of the above-mentioned 518 consecutive patients. The mitral valve area was significantly larger in group A than in group B, both immediately after MBV (2.0+/-0.3 vs. 1.82+/-0.3 cm2, respectively; P<0.0001) and also at the last follow-up (1.8+/-0.33 vs. 1.5+/-0.33 cm2, respectively; P<0.0001). Restenosis occurred in 38/340 (11%) in group A vs. 73/178 (41%) in group B (P<0.0001). Actuarial freedom from restenosis at 5, 10, 15 years were 92+/-2%, 85+/-3%, 65+/-6% for group A vs. 72+/-4%, 44+/-5%, 9+/-6% for group B (P<0.001). Event-free survival rates at 5, 10, 15 years for group A were 93+/-1%, 88+/-2%, 66+/-6% vs. 82+/-3%, 59+/-6%, 8+/-7% for group B (P<0.0001). Stepwise Cox multivariate regression analysis identified MES, preprocedure functional class, and postprocedure mitral valve area相似文献   
12.
岛状皮瓣静脉淤血再通后对大鼠全身情况的影响   总被引:4,自引:0,他引:4  
目的:探讨岛状皮瓣静脉淤血再通后对全身多脏器的影响。方法:按静脉淤血时间的不同将大鼠分为4组。观察耳部微循环的改变,测量术后肿瘤坏死因子α(TNFα),白细胞介素10(IL-10)的动态变化,观察心,肺,肝,肾,小肠及耳部血管等组织结构及中性粒细胞浸润数目。结果:皮瓣原位缝合组及静脉淤血2h组,耳部微循环、TNFα、IL-10浓度基本保持不变,各脏器结构改变较轻,中性粒细胞浸润数目少。静脉淤血6、10h组,微循环,肺,小肠,血管则有明显组织学改变,大量中性粒细胞浸润其中,但心,肝,肾组织学改变较轻。TNFα浓度再灌注1h达到高峰,其后逐渐下降,IL-10浓度3h达到最低,然后逐渐上升。结论:皮瓣静脉淤血再通后可造成肺、小肠及血管器官损伤,静脉淤血时间越长,再通后则损伤程度越重。全身微循环的改变,中性粒细胞在肺、小肠中的浸润,与血管内皮细胞的粘附及细胞因子TNFα与IL-10的浓度失衡是重要的操作原因。  相似文献   
13.
腹部手术后并发下肢深静脉血栓16例分析   总被引:1,自引:0,他引:1  
赵占吉  陈晓  毛谡  范筱勇  张军 《腹部外科》2003,16(6):366-367
目的 探讨腹部手术后并发下肢深静脉血栓形成 (DVT)的原因、诊治要点和预防措施。方法 回顾性分析 1 6例腹部手术后并发DVT病人的临床特点及诊断、治疗方法。结果 发生DVT的高危因素是复合创伤、恶性肿瘤、血粘度增高、老年病人、合并高血压病、糖尿病及术后常规应用止血药等。本组 1 6例均治愈 ,无一例发生肺栓塞等严重后果。结论 腹部手术后并发DVT者要积极早期治疗 ,对发生DVT的高危人群术前、术后应采取预防措施  相似文献   
14.
Complications following free tissue transfer have been well established in the literature. Common and rare causes of free flap failure must be addressed by the treating surgeon when microvascular patency is threatened. With the evolution and prevalence of microsurgery, ‘rare’ causes of free flap failure will become increasingly frequent. A high index of suspicion must be established in patients with multiple failed operative interventions. A case of recurrent free flap failure secondary to heparin-induced thrombocytopenia is presented in a patient with a history of squamous cell carcinoma of the floor of the mouth, and a long-standing history of alcohol and tobacco consumption.  相似文献   
15.
In this study, human umbilical vein and human saphenous vein endothelial cells were seeded on glass and exposed to fluid shear in a parallel-plate flow chamber. Cell retention, morphology and migration were studied as a function of shear stress and of adhesion time prior to exposure to shear. Three-hour and 24-h adhesion times gave rise to comparable cell retention values after 2 h of flow for both cell types. Cell retention decreased from 85 to 20% as shear stress increased from 88 to 264 dynes cm−2 (8.8 to 26 Pa). Mean spreading areas decreased after the onset of flow, but subsequently stabilized to plateau values, which were smaller at higher shear stresses. Shape factors increased faster to higher values as cells were exposed to higher shear stresses, without any obvious preference in orientation of the cells with respect to the direction of flow. Migration was unidirectional with flow and linear with time. Migration was faster for cells which had adhered for 24 h than for cells which had adhered for 3 h and was accompanied by the presence of fibrillar structures left behind on the surface upstream of migrating cells. It is concluded that after 3 h adhesion to glass, cells have adhered with an adhesion strength that does not substantially increase during the next 21 h. However, during this time changes in cell-substratum interactions seem to occur judging by the differences in, e.g., migration rates.  相似文献   
16.
静脉血气分析及其临床应用进展   总被引:2,自引:0,他引:2  
张德平 《医学研究生学报》2004,17(8):741-743,748
动脉血气分析是严重心肺疾病和许多代谢性疾病的重要检测手段,在血流动力学稳定状态下,动、静脉血气的CO2气体含量和酸碱参数非常接近,但在循环功能衰竭等情况下,动、静脉血气出现分离现象,此时可能需同时作静脉血气。静脉血气分析对危重患者特别是循环衰竭的患者可以提供组织氧合和酸碱状态更切实的评价,并可能对有效复苏提供更好的指导。  相似文献   
17.
本文报告我院外科1985~1987年,使用应变容积描绘仪检查下肢深静脉机能不全30例。其中28例同时行Doppler超声检查,27例行静脉造影检查。介绍了测量最大静脉输出量,最大静脉逆流量和静脉再充盈时间的方法和结果,叙述了该技术的原理,在诊断下肢静脉机能不全时,应变应变容积描绘仪是较好的无损伤检查技术。  相似文献   
18.
Background: We performed a phase I study of a novel system of complete hepatic venous isolation and extracorporeal chemofiltration in patients with unresectable hepatocellular carcinoma (HCC) to determine (a) whether systemic exposure to doxorubicin could be limited after high-dose hepatic arterial infusion (HAI), and (b) the hepatic maximum tolerated dose (MTD) of doxorubicin. Methods: Ten patients with biopsy-proven HCC were treated with 20-min HAI of doxorubicin (17 total treatments). Two patients were treated with doxorubicin 60 mg/m2, three patients were treated at 90 mg/m2, and five patients received 120 mg/m2. A newly developed dual-balloon vena cava catheter was advanced from the femoral vein, and the balloons were inflated to isolate and capture total hepatic venous outflow. The hepatic venous blood was pumped through extracorporeal carbon chemofilters before return of the blood to the systemic circulation. Results: Peak systemic doxorubicin levels were an average 85.6% lower than were peak prefilter levels (p<0.01). Because all catheters were placed percutaneously and because the chemofiltration markedly limited systemic chemotherapy exposure, patients were discharged 1 day after 16 of the 17 treatments. The hepatic and systemic MTD of doxorubicin in this treatment protocol was 120 mg/m2. Conclusions: This novel system of complete hepatic venous isolation and chemofiltration limits systemic chemotherapy toxicity and will allow use of higher doses of chemotherapeutic agents to treat HCC. The results of this study were presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993.  相似文献   
19.
本文通过应用彩色多普勒及激光荧光染料显示射流方法研究了不同形状界面对射流的影响。结果表明对照组及平坦界面射流时,彩色多普勒与激光荧光染料两种方法无显著差异;在弯曲界面条件下,彩色多普勒射流小于激光荧光染料射流(P<0.01~0.0001)。彩色多普勒研究表明不同形状界面射流大小分别与每搏容量相关好(r=0.83~0.99),但射流大小明显不同。凹形界面射流面积最小,平坦及凸形界面射流面积也小于对照组。研究提示不同形状界面可以导致界面射流不同程度地减小,并且彩色多普勒也不易对弯曲界面的射流完全成像。在临床上应用彩色多普勒对返流定量时,需考虑上述影响。  相似文献   
20.
目的探讨下肢深静脉血栓形成MR血管成像(MRA)的临床价值。方法对30例怀疑下肢深静脉血栓形成的患者进行了MRA和DSA检查,MRA采用二维时间飞越法(2DTOF)。对MRA与DSA表现进行对照分析。结果下肢深静脉血栓形成的MRA表现有1静脉充盈缺损(14例)、静脉闭塞和中断(8例)、静脉再通(3例)、侧支循环形成(25例)。以DSA为标准,MRA诊断出所有病变,但有1例假阳性。结论MRA作为无创性检查,是诊断下肢深静脉血栓有效的检查方法之一。  相似文献   
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