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31.
Summary

Conventional laparoscopy has not yet been widely adopted for procedures involving the retroperitoneal organs, due to the problems of adequate bowel retraction and the poor access afforded by the position of the root of the mesentery. Developments in retroperitoneal laparoscopy facilitated by balloon dissection have afforded a new minimally invasive approach to the retroperito-neum. We have compared retroperitoneoscopic and laparoscopic approaches to the great vessels in a porcine model.  相似文献   
32.
Summary

We report the use of a vascular surgical device to provide safe closure of the arterial access site after abdominal aortic-stent implantation. After suture-mediated percutaneous closure of the arterial puncture site, bleeding stopped immediately. There was no need for adjunctive compression. Immobilisation of the patient lasted only 1 h.  相似文献   
33.
目的 探讨超声心动图对小儿主动脉缩窄的诊断价值.方法 经超声心动图诊断的主动脉缩窄50例,男33例,女17例,年龄5天~11岁(中位年龄9个月零9天),均经手术和(或)造影证实.超声心动图检查在胸骨上主动脉弓长轴切面观显示主动脉弓及其三分支,确定缩窄范围和类型.彩色多普勒超声心动图显示主动脉缩窄处血流,频谱多普勒测量缩窄处血流速度.结果 50例患儿中,局限性缩窄23例,占46.00%;管状缩窄27例,占54.00%;33例合并动脉导管未闭.结论 将小儿主动脉缩窄分为管状缩窄和局限性缩窄可能更为合理;管状主动脉缩窄较常见.  相似文献   
34.
Concordance between programmed stimulation and 24 hour ambulatory electrocardiographic (Holter) monitoring was studied in 54 patients with sustained ventricular tachycardia during 84 therapeutic trials with class IA antiarrhythmic agents. During baseline studies before treatment, all patients had frequent (greater than or equal to 30/h) ventricular premature complexes on Holter recordings and sustained ventricular tachycardia inducible by one to three extrastimuli. During treatment, programmed stimulation and Holter monitoring were repeated. Efficacy of treatment determined by programmed stimulation (ventricular tachycardia no longer inducible or nonsustained) was compared with three Holter criteria of efficacy: I = 83% or more reduction of ventricular premature complexes and abolition of ventricular tachycardia; II = 50% or more reduction of ventricular premature complexes and 90% or more reduction of couplets and abolition of ventricular tachycardia; III = abolition of ventricular tachycardia in patients with ventricular tachycardia during a baseline Holter recording. Treatments were judged effective by programmed stimulation criteria in only 25% of cases but in 51, 63 and 75% of cases by Holter criterion I, II and III, respectively. Results of programmed stimulation and Holter monitor were discordant (effective by one criterion but ineffective by the other) in 50% of cases using Holter criterion I, in 54% using Holter criterion II and in 61% using Holter criterion III. In the majority of discordant results, treatments appeared efficacious by Holter criteria but ineffective by programmed stimulation criteria, suggesting insensitivity of efficacy by Holter criteria or nonspecificity of induced ventricular tachycardia during treatment, or both.  相似文献   
35.
Two enzymes, lipoprotein lipase (LPL) and hepatic triglyceride lipase (HTGL), are released into human plasma after intravenous injection of heparin. LPL is the major enzyme responsible for initiating catabolism of chylomicrons and very-low-density lipoproteins (VLDL). The physiological role of HTGL is less certain. HTGL has been postulated to be an alternate enzyme to LPL in hydrolysis of triglyceride in VLDL and to be an important enzyme for removal of phospholipid from both low-density lipoproteins (LDL) and high-density lipoproteins (HDL). In this latter role, this enzyme would convert larger, lighter lipoprotein particles to smaller denser particles. HTGL deficiency has been found in severe liver disease and with a genetic deficiency of this enzyme. A unique patient is described with acquired hepatic triglyceride lipase deficiency and vitamin A intoxication. This patient developed hypercholesterolemia with an increase in both LDL and HDL. An increased proportion of lighter LDL (LDL1) and HDL (HDL2) was noted. In addition, after administration of heparin there was no shift in the distribution of apoE in plasma fractionated using a column containing 4% agarose. These findings are consistent with a postulated role of HTGL in metabolism of light LDL and HDL particles and some classes of apoE containing lipoproteins.  相似文献   
36.
腹主动脉阻断导致内脏缺血再灌注损伤的研究   总被引:3,自引:0,他引:3  
目的观察腹主动脉阻断所引起的肝、肾、小肠等内脏缺血再灌注损伤的改变。方法建立小猪腹主动脉阻断1小时的模型,检测在不同再灌注时点组织及血液中丙二醛(MDA)和超氧化物歧化酶(SOD)的变化,同时检测肝肾功能和动脉血气分析,观察动物术后的生存情况。结果与缺血前比较,大多数再灌注时点血、组织中MDA明显升高,而SOD明显降低(P<0.05)。在再灌注2小时,血中谷丙转氨酶(ALT)、尿素氮(BUN)、肌酐(CRE)较缺血前明显升高(P<0.01),代谢性酸中毒也极为明显。多数动物术后能够存活,但均出现下肢截瘫。结论腹主动脉阻断1小时能引起明显的内脏缺血再灌注损伤改变,多数内脏经处理后其损伤能够得到代偿恢复,而脊髓损伤恢复困难。  相似文献   
37.
Measurement of vessel wall strain using cine phase contrast MRI   总被引:3,自引:0,他引:3  
PURPOSE: To determine the feasibility of using magnetic resonance imaging (MRI) to non-invasively measure strain in the aortic wall. MATERIALS AND METHODS: Cine phase contrast MRI was used to measure the velocity of the aortic wall and calculate changes in circumferential strain over the cardiac cycle. A deformable vessel phantom was used for initial testing and in vitro validation. Ultrasonic sonomicrometer crystals were attached to the vessel wall and used as a gold standard. RESULTS: In the in vitro validation, MRI-calculated wall displacements were within 0.02 mm of the sonomicrometer measurements when maximal displacement was 0.28 mm. The measured maximum strain in vitro was 0.02. The in vivo results were on the same order as prior results using ultrasound echo-tracking. CONCLUSION: Results of in vivo studies and measurement of cyclic strain in human thoracic and abdominal aortas demonstrate the feasibility of the technique.  相似文献   
38.
目的探讨三血管气管-肺动脉分叉切面在诊断单侧肺动脉异常起源于升主动脉(AOPA)中的应用价值。方法选取我院确诊的5例AOPA,总结AOPA在该切面声像图特点,结合随访病理解剖和其他影像学复查情况与产前超声诊断进行对比分析。结果在5例患儿中左肺动脉异常起源主动脉弓(AOLPA)4例,右肺动脉异位起源主动脉弓(AORPA)1例,同时合并其他心内畸形者2例,远端型4例,近端型1例。结论超声检查是诊断胎儿单侧肺动脉异常起源主动脉弓的重要方法,三血管气管-肺动脉分叉切面有其特殊的声像图表现,能提高对本病的认识降低误、漏诊率。  相似文献   
39.
目的 探讨主动脉缩窄矫治术后近、中期血管结构与功能改变.方法 选取20例确诊主动脉缩窄(CoA)并行手术矫治的患儿(CoA组),其中单纯性主动脉缩窄6例,复合性主动脉缩窄(合并其他心内畸形)14例;同期20例单纯室间隔缺损(VSD)患儿(VSD组)作对照,均于术前至术后1年监测血压,超声下颈总动脉内中膜厚度(IMT)和肱动脉血流介导的血管舒张功能(FMD).20例健康儿童(健康组)进行1年的随访.结果 术前、术后1个月、术后6个月、术后1年3组均无高血压临床表现.CoA组的颈总动脉IMT[(0.47±0.10) mm,(0.49±0.10) mm、(0.57±0.07) mm、(0.61±0.07)mm]均高于同期的VSD组[(0.41±0.11) mm,(0.43±0.11) mm,(0.51±0.08) mm,(0.55±0.08) mm]与健康组[(0.40±0,09) mm、(0.42±0.11) mm、(0.50±0.08)mm、(0.57±0.08) mm],差异均有统计学意义,P<0.05.CoA组的肱动脉FMD[(5.46±1.51)%、(5.71±1.88)%、(5.42±1.69)%、(5.27±1.02)%]均明显低于VSD组[(6.69±1.45)%、(6.66±1.21)%、(6.81±1.03)%、(6.43±1.34)%]和健康组[(6.59±1.84)%,(6.84±1.41)%、(6.91±1.31)%、(6.56±1.62)%],差异均有统计学意义,P<0.05.而上述两个指标在VSD组与健康组之间均差异无统计学意义,P>0.05.结论 主动脉缩窄矫治术后患儿仍存在血管结构和内皮功能异常,提示手术纠治主动脉缩窄后血管损害持续存在,可能是主动脉缩窄矫治术后患儿心血管疾病发生率高于健康儿童的原因.  相似文献   
40.
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