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51.
Objective To assess the effect of the balloon valvuloplasty for congenital valvular aortic stenosis (AS) in children.Methods A total of 27 (mean age 6.09 years) children with AS accepted the treatment of percutaneous balloon aortic valvuloplasty (PBAV).The ratios of balloon/valve were 0.95±0.08 for 19 cases of typical AS and 1.00±0.11 for 8 cases of hyp oplastic AS.The patients were evaluated by the gradients across aotic valves i n pre- and post-PBAV and by echocardiogram during the follow-up period.Results Fifteen of 19 (78.9%)cases of typical AS had a better outcome and the gradien t of the remaining 4 cases (26.7%) had increased after follow-up (ΔP>50 mm Hg).Four of 8 (50.0%) cases of hypoplastic AS had satisfactory responses and the gradient of the remaining 3 cases (75.0%) rose.There was no moderate to s evere aortic insufficiency (AI). Conclusion The balloon aortic valvuloplasty provides safe and significant hemodynamic and c linical improvement in pediatric patients.The outcome of PBAV for typical AS is better than for hypoplastic AS. 相似文献
52.
本文分析经皮球囊二尖瓣成形术治疗风湿性二尖瓣狭窄的疗效。结果表明 ,PBMV耗费少 ,住院期短。效果良好 ,值得推广应用 相似文献
53.
球囊血管成形术后再狭窄中ET和IGF—I的改变 总被引:3,自引:0,他引:3
目的 探讨内皮素(endothelin,ET)及胰岛素样生长因子-I(insulin like growth factor-I,IGF-I)在球囊损伤血管内皮后的改变及意义。方法 用自制导管制造大鼠血管内皮损伤模型,观察不同损血管病理改变,同时用放射免疫法测定血将ET及IGF-I含量。结果 血管内皮损伤后,随着时间延长,平滑肌细胞大量增殖造成管腔狭窄,将ET及IGF-I升高明显,各时间点与对照组相比均有显著性差异,且两者具有较好相关性。结论 ET与IGF-I相互作用促进血管平滑肌增殖,两者可能共同能与了球囊血管成形术后再狭窄的病理过程。 相似文献
54.
目的评价经皮二尖瓣球囊扩张术(PBMV)治疗二尖瓣狭窄伴中或重度肺动脉高压的疗效。方法用Inoue球囊导管行PBMV治疗二尖瓣狭窄伴肺动脉收缩压≥60mmHg(8.00kPa)患者101例。用超声心动图和心导管法观察血流动力学效应。结果术后血流动力学明显改善,二尖瓣瓣口面积增加(P〈0.01);肺动脉收缩压及肺循环阻力明显降低(P〈0.001),这些变化在心房颤中层得中尤为明显。结论PBMV治疗严 相似文献
55.
56.
Masahiko Igarashi Yuki Takeda Seijiro Mori Naoko Ishibashi Eiichi Komatsu Kentaro Takahashi Tsunekazu Fuse Mikako Yamamura Kazuki Kubo Yasuo Sugiyama Yasushi Saito 《British journal of pharmacology》1997,120(6):1172-1178
- The aim of this study was to determine whether BAYw6228 (BAYw), a newly developed 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitor, could suppress an atherogenic process such as intimal thickening by a mechanism other than lowering the level of serum cholesterol.
- First, we evaluated the in vitro effect of BAYw on the proliferation of vascular smooth muscle cells (SMC) from various species: Sprague-Dawley (SD) rats, New Zealand (NZ) white rabbits, intimal cells from Watanabe hereditary hyperlipidemic (WHHL) rabbit and SMC from the new-born human aorta. The increasing rate of total protein content of these cells was inhibited by the addition of BAYw in a dose-dependent fashion. In the presence of 2% foetal calf serum (FCS), the value of IC50 was 1.0 μM in SD rats. 2.1 μM in NZ white rabbits, and 0.3 μM in WHHL rabbits. With human SMC, the value was 0.02 μM in the presence of 10% FCS and 0.2 μM with a mixture of growth factors.
- Based on these above in vitro findings, we next examined the in vivo effect of the agent to determine whether it could suppress rabbit intimal thickening induced by balloon catheterization. A balloon catheter was inserted from a peripheral branch of the left external carotid artery to the aorta to denude the endothelium of the left common carotid artery in Japanese white rabbits. After 12 days they were divided into control and BAYw groups. The former were subcutaneously injected with saline and the latter with BAYw 1 mg kg−1 day−1. Two days after the beginning of treatment, a second balloon injury was performed to the previously injured left common carotid artery in both groups. After another two weeks, the left common carotid artery was removed and variously stained. Although the total serum cholesterol in the BAYw group was significantly lower than in the control (P<0.05), the difference was not enough to affect intimal thickening. In addition, the BAYw group had a smaller intima/media ratio than the control group, decreasing to 45% of control (P<0.05). By anti-α smooth muscle actin antibody staining, these intimal thickening areas were entirely occupied by SMCs, and their amount was attenuated by BAYw. By anti-rabbit macrophage antibody (RAM 11) staining, the number of positive cells in the intimal thickening was markedly decreased in the BAYw group compared to control (P<0.01).
- These results indicate that BAYw has an inhibitory effect on intimal thickening by attenuating intimal SMC proliferation and infiltration of macrophages, suggesting that BAYw could be effective in the prevention of the progression of atherosclerotic plaque-like restenosis after angioplasty.
57.
为建立闭合性脑硬膜外占位性颅脑损伤的大鼠模型,利用5F 漂浮导管置脑硬膜外模拟占位,按球囊注入水量和持续时间分组。观察各组动物的死亡率,存活鼠的颅内压、脑含水量的变化以及血肿形成、组织受损的情况。结果显示:球囊越大,持续时间越长,损伤越大;存活鼠颅内压及脑水含量均增加,神经机能受损,并有血肿形成和受压区坏死;上述变化随占位时间延长和受压程度的加重而加重。提示该脑损伤模型简单可行、可重复,能较好地反映硬膜外占位性脑损伤的病理分级,且经济实用 相似文献
58.
谷子种子经高空气球搭载后的遗传变异研究 总被引:11,自引:2,他引:9
目的 选育出高产、蛋白质和用脂肪含量高的谷子品(系)种。方法 利用高空气球搭载谷子的干种子,在高空飘游8h后回收种植,对其植物学特性及进行分析研究。结果 种子发芽率比对照低5.2%,发芽热比对照高21.1%。SP1代植株高度比对照低6.8cm,旗叶面积比对照高25%,穗重比对照高15.9%;SP3代大穗型株系性状相对稳定,其中SP3-2的种子蛋白质和脂肪含量均高于对照经高空气球搭载后的SPE-35 相似文献
59.
Gastroplasty is currently one of the most common surgical procedures performed on the morbidly obese for weight loss. An adequate
result can be assured only if the pouch that is created is less than 30 ml and the channel that connects that pouch to the
distal stomach is approximately 1 cm in diameter. The current method to size the pouch is to occlude the esophagus and the
outlet of the pouch and to measure with a manometer through a naso-gastric tube. We contend this method is both time consuming
and adds to the potential of complications. Through the use of a calibration balloon tube the size of the pouch can be quickly
and safely estimated. It can also be used to size the channel between the pouch and the distal stomach and check for leaks.
The technique of how this tube has been used over the past 6 years is described. By the use of a calibration balloon tube,
three problem areas in gastric stapling surgery for morbid obesity are avoided, namely: inappropriate pouch size, inappropriate
channel size and postoperative leaks. 相似文献
60.
Mataichi Ohkubo Ken Takahashi Masahiko Kishiro Katsumi Akimoto Yuichiro Yamashiro 《Pediatrics international》2004,46(1):39-47
Abstract Background : Use of balloon angioplasty or stent implantation has been reported to be effective in relieving coarctation of the aorta. However, restenosis frequently occurs after balloon angioplasty for native aortic coarctation in small infants, and sometimes develops after stent implantation because of vessel growth. The causes of restenosis remain uncertain. The purpose of this study was to assess the histologic differences in vascular responses to angioplasty using conventional balloon, radiofrequency thermal balloon (RFTB), or stent for experimental aortic coarctation. Methods : The authors surgically created an aortic coarctation model using 14 puppies. Angioplasty using conventional balloon, RFTB, or stent was performed 1 month after the initial operation. At the acute or chronic phase after angioplasty, the animals were killed and histologic studies were performed. Results : More vascular injuries were noted in the specimens from animals undergoing conventional angioplasty than in those with RFTB or stent. However, neointimal hyperplasia was seen more often after RFTB or stent because of the proliferation of smooth muscle cells from the tunica media, caused by secretion of growth factors. Apoptosis reached a peak 1?2 weeks after angioplasty, regardless of the type of intervention. Conclusions : The authors conclude that angioplasty with RFTB or stent can provide relatively small injuries in the vessel wall for aortic coarctation, but care must be taken to prevent restenosis caused by intimal hyperplasia, because neointima hyperplasia is more frequent after RFTB or stent. 相似文献