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81.
目的比较使用桡动脉和乳内动脉全动脉化冠状动脉旁路移植术(CABG)与使用一根乳内动脉和静脉做常规CABG的近期手术结果。方法从1999年1月到2005年1月,阜外心血管病医院共有123例患者(男114例、女9例,年龄52.2±10.1岁)采用全动脉化CABG(全动脉化组),血管移植材料为乳内动脉和桡动脉,目标血管桥在2根以上;同期行常规CABG115例(男102例、女13例,年龄60.3±9.1岁),血管的移植材料为一根乳内动脉和若干静脉桥(常规手术组)。比较两组患者术前、术中和术后的临床结果。结果术前资料比较,全动脉化组的患者年龄更小,常规手术组3支病变患者较多(54.5%vs.86.1%,P=0.001),全动脉化组有更多患者选择非体外循环CABG(26.0%vs.57.4%,P=0.001);在体外循环CABG中,全动脉化组需要更长的手术时间;平均移植血管根数全动脉化组少于常规手术组(2.6±0.7根vs.3.4±0.9根,P=0.001);住院死亡率全动脉化组为0.8%,常规手术组为0.9%,两组比较差异无统计学意义(P=1.000);术后近期并发症发生情况两组结果相似。结论对选择适合的患者采用全动脉化CABG能够提供较为安全的近期手术结果。 相似文献
82.
Intra-operative quick insulin assay to confirm complete resection of insulinomas guided by selective arterial calcium injection (SACI) 总被引:1,自引:0,他引:1
Oliver Gimm Evelyn König Phuong Nguyen Thanh Michael Brauckhoff Wolfram Karges Henning Dralle 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(6):679-684
Background and aims Insulinomas are rare endocrine disorders. Pre-operatively, conventional imaging techniques often fail to localise the tumor.
In addition, due to the lack of quick insulin assays, intra-operative confirmation of complete resection was impossible until
recently.
Materials and methods Six patients with biochemical evidence of an insulinoma underwent pre-operative localisation studies and selective arterial
calcium injection (SACI). In addition, insulin was measured before surgery and every 10–15 min after resection of the tumor
using a quick insulin assay.
Results Pre-operative localisation studies identified the tumor correctly as follows: endosonography: three of four, magnetic resonance
imaging: two of four and SACI: six of six. Tumors in the head and body were enucleated while those in the tail were resected
(n = 2, each). Those three patients, in whom magnetic resonance imaging and/or endosonography could localise the tumors pre-operatively,
underwent laparoscopic surgery while the remaining three patients underwent open surgery. Intra-operatively, insulin dropped
to normal levels within 20 min in all cases. After a follow-up of 0.8–3 years, all patients remained biochemically cured.
Conclusions Pre-operatively, SACI appears to be a very sensitive localisation technique and may be most helpful in guiding the surgeon
if conventional imaging techniques fail to localise the tumor. Complete removal of an insulinoma can be reliably predicted
using a quick insulin assay.
This paper was presented at the 2nd Biennial Meeting of the European Society of Endocrine Surgeons (ESES), May 18–20, 2006,
Krakow, Poland. 相似文献
83.
Yu-Te Wu Yen-Chun Chou Wan-Yuo Guo Tzu-Chen Yeh Jen-Chuen Hsieh 《Magnetic resonance in medicine》2007,57(1):181-191
The ability to cluster different perfusion compartments in the brain is critical for analyzing brain perfusion. This study presents a method based on a mixture of multivariate Gaussians (MoMG) and the expectation-maximization (EM) algorithm to dissect various perfusion compartments from dynamic susceptibility contrast (DSC) MR images so that each compartment comprises pixels of similar signal-time curves. This EM-based method provides an objective way to 1) delineate an area to serve as the in-plane arterial input function (AIF) of the feeding artery for adjacent tissues to better quantify the relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), and mean transit time (MTT); 2) demarcate regions with abnormal perfusion derangement to facilitate diagnosis; and 3) obtain parametric maps with supplementary information, such as temporal scenarios and recirculation of contrast agent. Results from normal subjects show that perfusion cascade manifests (in order of appearance) the arteries, gray matter (GM), white matter (WM), veins and sinuses, and choroid plexus mixed with cerebrospinal fluid (CSF). The averaged rCBV, rCBF, and MTT ratios between GM and WM are in good agreement with those in the literature. Results from a patient with cerebral arteriovenous malformation (CAVM) showed distinct spatiotemporal characteristics between perfusion patterns, which allowed differentiation between pathological and nonpathological areas. 相似文献
84.
异搏定区域动脉灌注在阻止急性胰腺炎重症化治疗中的作用 总被引:1,自引:1,他引:0
目的探讨钙拮抗剂异搏定区域动脉灌注在阻止急性胰腺炎重症化治疗中的作用。方法45例轻型急性胰腺炎患者被随机分为3组常规治疗组、静脉治疗组及动脉灌注组。入院后,常规治疗组采取常规保守治疗;静脉治疗组行合理液体治疗,静脉注射异搏定;动脉灌注组液体补充同时采用持续动脉灌注异搏定1~2周。测定治疗后1、4及7d血清肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)、黏附分子-1(ICAM-1)及P-选择素(P-selectin)水平。结果治疗后4、7d,血清TNF-α和P-selectin水平动脉灌注组较静脉治疗组及常规治疗组明显降低(P<0.05);血清IL-1β水平动脉灌注组和静脉治疗组均较常规治疗组明显降低(P<0.05);血清ICAM-1水平动脉灌注组明显低于常规治疗组(P<0.05)。结论持续区域动脉灌注异搏定可能通过减少细胞因子的产生,抑制黏附分子P-selectin和ICAM-1的上调,阻止急性胰腺炎重症化发展。 相似文献
85.
血浆血管内皮细胞生长因子与肝细胞癌临床特征的相关性 总被引:1,自引:0,他引:1
目的通过检测肝细胞癌(HCC)患者肝动脉栓塞术前血浆血管内皮细胞生长因子(VEGF),考察VEGF表达与肿瘤大小、边界、门脉癌栓、远隔转移之间的相关性。方法收集介入治疗前HCC患者46例,VEGF定量检测采用双抗体夹心酶ABC ELISA法。根据血浆VEFG表达水平将患者分为阳性组(32例)和阴性组(14例),对肿瘤大小、边界、门脉癌栓、远隔转移情况进行组间对比。CT和DSA间接门脉造影获得的图像进行对比评估。结果VEGF阳性表达率69.56%(32/46),阴性表达率30.44%(14/46)。VEGF阳性组肿瘤直径>5cm者26例(81.25%),阴性组12例(85.75%),两组间无显著性差异(P>0.05)。CT片上阳性组肿瘤边界清楚15例(46.88%),阴性组边界清楚8例(57.14%),组间无显著性差异。阳性组门脉癌栓发生率62.50%(20/32),阴性组14.29%(2/14),两组间有极显著性差异(P<0.01)。阳性组远隔转移8例;阴性组无远隔转移,经检验P<0.05。结论血浆VEGF高表达可以提示门脉癌栓或远隔转移的存在,而与肿瘤大小、边界无关。血浆VEGF可能成为观察肿瘤门脉癌栓及远隔转移的指标。 相似文献
86.
经肝动脉灌注三氧化二砷对肝移植瘤血管的作用 总被引:5,自引:0,他引:5
目的 :探讨经肝动脉灌注As2 O3 对肝移植瘤血管的作用 .方法 :采用新西兰大白兔建立 5 0只肝脏Vx 2移植瘤动物模型 ,随机平均分成 5组 .移植瘤术后 2wk ,经肝动脉插管灌注不同浓度As2 O3 ,并以顺铂和生理盐水作对照 ,连续 7d ,6wk末切取肝肿瘤组织 ,观察肿瘤组织微血管有无改变 ,检测移植瘤组织血管内皮生长因子 (VEGF)的表达 .结果 :实验组肿瘤组织毛细血管内皮细胞肿胀、细胞核碎裂、细胞坏死及微血栓形成 ,阴性对照组和阳性对照组无类似改变 .实验组VEGF表达低于对照组 ,差异有显著性 (P <0 .0 1 ) ,而实验组间VEGF表达无差异性 (P =1 .0 0 ) .结论 :经肝动脉灌注As2 O3可减少肿瘤组织的血管生成 ;选择性破坏肝移植瘤组织血管 ,并存在一定剂量效应相关性 相似文献
87.
Richard Werner Karsten Alfke Tobias Schaeffter Arya Nabavi H Maximilian Mehdorn Olav Jansen 《Magnetic resonance in medicine》2004,52(6):1443-1447
A new method for the selective spin labeling of left- or right-sided supplying arteries of the brain without the need for additional RF coils is demonstrated. A clinical 1.5 T scanner was used. The spatial selectivity of the labeling process is based on the limited coverage of the excitation field of a standard send/receive head coil together with an oblique positioning of the labeling plane. A computer simulation was used to optimize key labeling parameters under the condition of laminar flow. The validity of the computer model results was confirmed by MRI measurements with a flow model. For human studies, a double-inversion continuous arterial spin labeling (CASL) sequence was modified to allow for arbitrary positioning of the labeling plane. The obtained perfusion-weighted images showed a clear delineation of the perfusion territories of the selected arteries in the anterior circulation of the brain and good gray/white matter contrast. 相似文献
88.
肝动脉解剖变异在中晚期肝癌介入治疗中的意义 总被引:1,自引:0,他引:1
目的 探讨放射学肝动脉解剖变异及其在中晚期肝癌介入导管治疗中的临床意义。方法 回顾性分析125例中晚期肝癌肝动脉造影表现及其介入治疗资料。结果 125例中107例(85.6%)有典型肝动脉分布。肝动脉变异18例(14.4%),其中肝右动脉变异10例(8%),而又以肝右动脉始于肠系膜上动脉者最多,占6.4%。副肝左动脉变异1例(0.8%)。肝左动脉和肝右动脉同时变异2例(1.6%)。肝总动脉变异3例(2.4%)。胃十二指肠动脉起自肝右动脉和腹腔动脉各1例(1.6%)。对123例成功进行了肝动脉化疗栓塞,2例肝右动脉变异因角度关系超选插管未成功。结论 认识肝动脉解剖变异有助于提高插管的成功率和中晚期肝癌的介入治疗疗效。 相似文献
89.
R. NIJLAND H. W. JONGSMA J. G. NlJHUIS B. OESEBURG 《Acta anaesthesiologica Scandinavica》1995,39(S107):71-76
A piglet model was used to evaluate the accuracy of a fiberoptic oximeter over a wide range of arterial oxygen saturation (SaO2 ) values. In eight anaesthetized piglets, the inspired oxygen concentration was varied from 30% to 6% resulting in a SaO2 range from 100% to 15%. Paired data of the Opticath® fiberoptic catheter, which was placed in the descending aorta, and blood sample SaO2 values assessed by a multiwavelength oximeter, were analysed. After in vitro calibration according to the manufacturer's instruction, the fiberoptic catheter started to underestimate the SaO2 below 78%, worsening towards lower SaO2 values. The overall bias was -3. 4% and the precision 3. 8%. An off-line fit with a non-linear model resulted in a standard deviation of residuals of 2. 6%. After several in vivo calibration adjustments when the Fiberoptic oximeter deviated more than 4% from the blood sample value, the bias was eliminated over the total SaO2 range and the precision was 3. 7%. The Opticath® fiberoptic oximeter could have an accuracy for the whole SaO2 range between 15–100% close to the accuracy of the multiwavelength oximeter, when the fiberoptic oximeter is adapted for the underestimation below 78% SaO2 . 相似文献
90.
W. D. Boeckx V. V. Vijay Haribhakti L. Bosmans J. A. Gruwez 《European journal of plastic surgery》1992,15(3):127-132
Summary In 50 rats, different types of end-to-side carotid artery anastomoses were compared. In one technique, a longitudinal split in the long axis of the vessel was performed to enhance the diameter of the anastomosis. This theoretical advantage was not confirmed in this series. The clamping time, anastomoses time, and tamponade time were increased significantly when compared with a simple, slightly oblique end-to-side anastomosis. This study highlighted that the most simple type of end-to-side anastomosis gave less bleeding, achieved a quicker water-tight anastomosis and decreased the risk of late problems. 相似文献