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41.
ICR 小白鼠脏器中铜,锌锰含量   总被引:1,自引:0,他引:1  
对40只正常成年远交系 ICR 小白鼠的主要脏器,用 WFX—Ⅱ型双光束原子吸收分光光度计测定了各脏器中铜、锌、锰含量.结果表明,主要脏器中铜、锌、锰含量大小顺序不一,铜含量最多的脏器是心,锌、锰含量最多的脏器是肝,在雌雄之间均无显著性差异.  相似文献   
42.
本文报告经皮球囊二尖瓣成形术治疗二尖瓣狭窄12例。10例术前平均左房压为18mmHg~40mmHg(26.7±7.15mmHg),术后即刻为4mmHg~18mmHg(10.6±3.86mmHg)P<0.01。跨瓣压差术前10mmHg~40mmHg(19.6±9.05mmHg),术后为0~5mmHg(2.65±2.21mmHg)P<0.01。1例失败,1例术后发生二尖瓣关闭不全急性左心衰竭死亡。  相似文献   
43.
The Magnum system, initially designed for coronary angioplasty (PTCA) of chronic total occlusion, consists of a balloon catheter and a solid steel 0.021 inch (0.53 mm) steerable and removable wire with a soft and moldable distal portion, tipped with a 1 mm olive. To evaluate its performance in routine PTCA, 200 unselected consecutive patients were randomized to two equal groups, i.e., group Magnum (100 patients, 115 vessels) and group Standard (100 patients, 118 vessels) including 18 and 21 patients with chronic total occlusions, respectively. Randomization was performed by the sealed envelope system in the catheterization laboratory and crossover of system was imposed if it was not possible to place a balloon correctly within 20 min of fluoroscopy time. There were no significant differences between groups concerning clinical and angiographic baseline characteristics, size of initial balloons (3.0±0.3 mm in both groups), fluoroscopy time to cross the lesion with the wire (Magnum: 4±5, Standard: 5±6 min), total fluoroscopy time (Magnum: 11 ± 9, Standard: 12±12 min), and need for crossover (Magnum: 10%, Standard: 16%). Success rates per lesion were comparable with 90% in group Magnum and 84% in group Standard, as were the complications with one inhospital death in group Standard, occurring three weeks after PTCA and stent implantation. There was no emergency operation. Six patients per group had myocardial infarction of whom two in group Magnum and one in group Standard developed a Q-wave. The following variables were significantly in favor of the Magnum system compared with the Standard system: success rate in nontotal lesions (97% versus 90%) crossover success in total occlusions (0 vs. 33%), fluoroscopy time to cross the lesion with the balloon once the wire was in place (1 ± 2 vs. 2 ± 4 min), and use of a single versus 1.2±0.5 wires per lesion. The only advantage of the Standard systems was the more common use of 7 French guiding catheters (Magnum: 40%, Standard: 53%, p = 0.09). The Magnum system compares favorably with standard systems for routine PTCA. The robust design of the Magnum wire does not impair ease of placement and safety but saves material and facilitates balloon advancement across the lesion.  相似文献   
44.
Coronary angioplasty is unsuccessful in <3–5% of cases because the balloon catheter fails to follow a guidewire that has traversed a lesion. Between June 1986 and August 1987, 31 lesions were unable to be crossed with at least two standard angioplasty catheters. Finally, a 2.0-mm-diameter Hartzler LPS (ACS) was utilized and successfully crossed and dilated 16 out of 31 lesions (52%). In the remaining 15 lesions, the ProbeTM (USCI) 2.0 mm diameter × 1.5 cm long balloon wire was able to cross the lesions in 13 (82%) and successfully dilated 12. In one case, lesion rigidity prevented the balloon from expanding at 14 atm. A right coronary artery lesion was attempted in 11 cases, and a left anterior descending and circumflex artery lesion in two patients each. No complications were encountered. In seven out of 12 successful ProbeTM cases, a larger balloon catheter was used to further dilate the artery. This new balloon wire has increased our success rate in severe stenoses and in tortuous vessels with severe distal lesions, in which presently available angioplasty equipment has failed.  相似文献   
45.
A new balloon electrode catheter (10 French) with five or six balloon electrodes placed on the cardiac side was developed for transesophageal atrial pacing and bipolar ECG recording. The diameter of the hemispheric electrodes is 6 mm and the length of the esophageal balloon is 10 cm. The transesophageal atrial pacing threshold was measured with the balloon electrode catheter by transesophageal programmed atrial stimulation (TPS) (n = 54). At the onset of TPS, the feeling, capture fn = 54), and pain voltage threshold (n = 6) were measured by increasing the amplitude of the pacing voltage during high rate bipolar atrial pacing and bipolar atrial ECG recording. In 38 TPS, the capture threshold was lower than the feeling threshold (n = 28). In 16 TPS, the capture threshold was higher than the feeling threshold. In conclusion, painless atrial pacing and excellent ECG recording can be achieved with a multipolar esophageal balloon electrode catheter with a low pacing voltage amplitude and a high P wave amplitude.  相似文献   
46.
复发性口腔溃疡患者血Cu,Fe,Zn含量分析   总被引:5,自引:0,他引:5  
目的:探讨微量元素在复发性口腔溃疡发病中的作用。方法:检测了44例复发性口腔溃疡患者血清微量元素Cu,Fe,Zn含量,并与正常健康人对照,统计结果用t检验。结果:复发性口腔溃疡患者血清Zn含量明显低于对照组,而Fe含量高于对照组。结论:提示缺Zn是诱发复发性口腔溃疡的因素之一。  相似文献   
47.
Four selected cases of emergent IABP insertion in PV patients are presented. After angiographic documentation of critical iliac stenosis, conservative peripheral angioplasty was performed prior to IABP insertion. No patient experienced a peripheral ischemic event associated with IABP use. © 1992 Wiley-Liss, Inc.  相似文献   
48.
孙滢滢  张少锋  周冰  孔亮 《中国美容医学》2006,15(2):173-174,i0007
目的:利用Matlab和Ansysworkbench软件辅助建立桩核冠三维有限元模型。方法:应用薄层CT技术,获取建模所需二维影像45张(层厚0.5mm,无间隔),利用Matlab软件编程读取图像边界数据,导入Ansys三维有限元专用软件,在Ansysworkbench环境中三维重组模型,同时进行模型单元划分和力学检测。结果:建立包含桩核、冠修复体、牙根、粘固剂、牙胶尖、牙周膜、松质骨和皮质骨的三维有限元模型。结论:利用Matlab软件和Ansysworkbench软件辅助建模,提高了建模的精度、速度和灵活性,为牙颌组织三维有限元建模提供了新的方法。  相似文献   
49.
目的对比分析胃镜下应用探条或自制气囊扩张治疗贲门失弛缓症的疗效。方法1998年1月~2007年12月,胃镜下治疗贲门失弛缓症45例,其中应用自制气囊扩张22例(自制气囊组),应用探条扩张23例(探条组),比较2组疗效。结果探条组23例扩张1~9次,平均3.6次;自制气囊组22例扩张1~6次,平均2.3次。2组术中及术后均无并发症发生。首次治疗费用探条组(1542.57±281.30)元,自制气囊组(861.91±176.48)元(t=9.671,P=0.000)。扩张后3个月的疗效2组差异无显著性[探条组显效14例(61%)、有效8例(35%)、无效1例(4%),自制气囊组显效15例(68%)、有效5例(23%)、无效2例(9%),Z=-0.351,P=0.726]。扩张后6个月的疗效2组差异有显著性[探条组显效5例(22%)、有效3例(13%)、无效15例(65%),自制气囊组显效10例(45%)、有效7例(32%)、无效5例(23%),Z=2.564,P=0.010]。结论胃镜下应用探条和自制气囊扩张治疗贲门失弛缓症安全、简便,患者恢复快,尤其自制气囊扩张器设备简单,就地取材,疗效肯定,在基层医院具有良好的推广价值。  相似文献   
50.
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