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141.
目的探讨螺旋CT(SCT)和MRI对主动脉瘤的诊断价值。方法25例主动脉瘤,13例行MRI检查,12例行SCT及三维重建技术检查。三维重建方法采用表面阴影显示法(SSD)、最大密度投影(MaxIP)及多层面重建法(MPVR)。结果13例主动脉夹层MRI和SCT均较好显示主动脉夹层内膜片和真假腔,SCT显示内膜破口5例,MRI无一例显示;SCT及三维重建较好地显示了主动脉夹层的内膜撕裂的范围、真性主动脉瘤(TAA)瘤壁的厚度及钙化、附壁血栓的情况及与邻近大血管分支的关系。结论SCT及三维重建技术的联合应用较低场MRI更能明确主动脉瘤的病变,对帮助和指导手术更具有价值。 相似文献
142.
颅内破裂动脉瘤手术时机的选择 总被引:5,自引:0,他引:5
目的探讨颅内破裂动脉瘤不同手术时机与临床预后的关系.方法回顾性分析121例前循环动脉瘤,其中延期手术夹闭97例,早期24例,采用不同的统计方法分析不同手术时机对预后的影响.结果早期手术夹闭24例中除1例V级患者于术后3d死亡和1例Ⅲ级患者于术后2月因颅内感染死亡外,余22例均获得优或良疗效;平均住院18.2d,无1例再出血,延期手术的97例平均住院时间是前者的2倍,14例发生再出血.结论早期显微外科治疗颅内破裂动脉瘤,尤其对Hunt&HessI~Ⅲ级患者,有利于缩短住院时间,降低保守治疗期间再出血的危险性,而对于Ⅳ~V级脑肿胀患者,早期手术的困难程度相应增加. 相似文献
143.
电解可脱性铂弹簧圈栓塞治疗颅内动脉瘤26例 总被引:2,自引:0,他引:2
目的:报告使用电解可脱性钱弹簧圈(Guglielmi detachable coil,GDC)栓塞治疗颅内动脉瘤的情况。方法:气管内插管全订和肝素抗凝下,使用Seldinger’s技术,经Tracker微导管放置GDC栓塞颅内动脉瘤。成功栓塞26例31个颅内动脉瘤,其中27个为100%栓塞,3个为95%,1个为90%。3个95%栓塞均为宽颈动脉瘤。1个90%栓塞者,为Hunt分级Ⅳ级,存在严重脑血 相似文献
144.
H Lauder L A Sellers T -P D Fan W Feniuk P P A Humphrey 《British journal of pharmacology》1997,122(4):663
- The aim of the present study was to determine the effect of somatostatin (SRIF) on mitogen-induced regeneration of rat aortic vascular smooth muscle cells (VSMC) and for comparison Chinese hamster ovary (CHO)-K1 cells expressing human recombinant sst5 receptors (CHOsst5), following partial denudation of a confluent cell monolayer. Regeneration was assessed by measuring areas of recovery into the denuded area and by counting total cell numbers.
- In VSMC, SRIF (0.1 nM–1 μM) had no effect on the basal levels of regeneration but caused a concentration-dependent inhibition (pIC50 8.0–8.6) of the stimulated regeneration induced by sub-maximal concentrations of basic fibroblast growth factor (bFGF, 10 ng ml−1), platelet-derived growth factor-BB (PDGF, 5 ng ml−1) or endothelin-1 (ET-1, 100 nM). SRIF (pIC50 8.8) also inhibited bFGF-induced regeneration of CHOsst5 cells.
- In VSMC, the inhibitory action of SRIF on the regeneration induced by bFGF (10 ng ml−1) was due to an anti-proliferative effect, rather than an effect on cell migration, as SRIF (0.1 nM–1 μM) abolished bFGF-induced increases in total cell numbers. The bFGF-induced increase in cell numbers was also abolished by actinomycin D (0.1 μg ml−1).
- The sst5 receptor-selective agonist, L-362,855 (pIC50 10.5), was about 100 times more potent than SRIF at inhibiting bFGF-induced regeneration of both VSMC and CHOsst5 cells whilst the sst2 receptor-selective agonist, BIM-23027 (pIC50 6.8), was approximately 20 times weaker than SRIF.
- The sst5 receptor antagonist, BIM-23056 (100 nM), antagonized SRIF-induced inhibition of bFGF-induced regeneration in both VSMC and CHOsst5 cells (estimated pKB values 8.8 and 8.3, respectively).
- SRIF-induced inhibition of bFGF-induced regeneration of VSMC and CHOsst5 cells was abolished by pretreating cells with pertussis toxin (100 ng ml−1) for 20 h.
- These findings suggest that SRIF-induced inhibition of the proliferation of rat aortic VSMC is mediated via activation of receptors which are similar to human sst5 receptors. Furthermore this inhibitory effect is transduced via pertussis toxin-sensitive Gi/Go proteins.
145.
Seventy-eight consecutive survivors of a first acute anteriorQ wave myocardial infarction (AMI) underwent two-dimensionalechocardiography (2D echo), colour Doppler echo and radionuclideangiography (RNA) for the diagnosis of left ventricular (LV)anteroapical aneurysm, in order to study the relationship ofthis complication to precordial ST segment elevation in thesepatients. The ST elevation (mm) in lead V2, the maximum ST elevationin V1-V6 and the sum of ST elevation in V1 to V6 were calculated.LV aneurysm was present in 19 patients by 2D echo, of whom 12had a paradoxical systolic flow pattern (red and outward towardsthe transducer) at the apex. There was no difference between the mean ST elevation in V2or the maximum ST elevation in V1-V6 in patients with and withoutan aneurysm, although the sum of ST elevations in V1 to V6 washigher in the former group (P<0.01). ST elevation of patientswith and without paradoxical systolic flow also did not differsignificantly. Wall motion abnormality (akinesis and dyskinesis)by 2D echo in the anterior wall was seen in 74% of patientswith and 36% of patients without an aneurysm (P<0.005), andin the septal region in 63% and 47% of respective patients (P-NS).There was no difference between the magnitude of ST elevationin subgroups of patients with ejection fraction (EF) 30% to40%, but the mean EF of patients with (23 ± 2.1%) andwithout a LV aneurysm (34 ± 1.3%) differed (P<0.001). It is concluded that precordial ST segment elevation does notclearly and in the diagnosis of an anteroapical LV aneurysm.It is related to akinesis and dyskinesis in anterior and septalregions inherent in patients with AMI and does not indicateimpaired LV function. 相似文献
146.
PONGRATZ G.; GANSSER R.; BACHMANN K.; SINGER H.; WORTH H. 《European heart journal》1994,15(7):1002-1004
Coronary aneurysms resulting from a previous episode of Kawasaki'sdisease are considered an important cause of myocardial infarctionin children. A case of a 19-year-old man presenting with anacute myocardial infarction associated with coronary aneurysmsis described. These coronary lesions were previously evaluatedangiographically and echocardiographically at the age of 13years, 5 months after the acute episode of a Kawasaki's disease. 相似文献
147.
The cross-sectional velocity distribution in the left ventricularoutflow tract was studied in 40 patients with valvular aorticstenosis. Doppler colour flow mapping and a time-interpolationmethod were used to construct the cross-sectional velocity andtime-velocity integral (TVI) profiles at different levels. Byusing pulsed Doppler, the subaorticflow velocity was sampledfrom the anterior, middle and posterior regions along the diameterof the left ventricular outflow tract (at 0.5 to 1.0 cm proximalto the aortic anulus) in the apical long axis view. Thus, foreach patient, three aortic valve areas were calculated by usingthe continuity equation. Each patient was assigned to one oft/treesubgroups according to the left ventricular ejection fraction(EF): subgroup I with EF25% (n=10), subgroup II with 25%<EF50%(n=17) and subgroup III with EF>50% (n = 13). Velocity distributionsin the three subgroups were compared to each other. Results:(1) The velocity distribution in the left ventricular outflowtract was skewed with the highest velocities and TVIs alongthe anterior wall and septum. The skewness of the velocity distributionwas more pronounced in the apical long axis view than in thefour chamber view (P<0.05). The extent of skewness of theTVI profile was positively correlated to the left ventricularEF both in the long axis view (r=0.63; P<0.001) and in thefour chamber view (r=057; P<0.001). (2) Pulsed Dopplersampling from different regions along the diameter produceddifferent TVIs, and therefore yielded significantly differentcalculated aortic valve areas, especially in subgroup III. Due to the skewness of the velocity distribution in the leftventricular outflow tract, location of the pulsed Doppler samplevolume significantly affects the accuracy of aortic valve areacalculation by using the continuity equation, especially inpatients with relatively high left ventricular EF. In patientswith low EF, selection of pulsed Doppler sampling site is lessimportant. 相似文献
148.
The anaesthetic management of the surgical repair of a descending aortic aneurysm in a patient with large, bilateral, pulmonary
bullae is described. Anaesthesia for descending aortic surgery normally involves unilateral, positive-pressure ventilation,
an option which poses some risk of barotrauma in the presence of bilateral bullae. Patients with bullous disease commonly
have severe lung disease and thorough preoperative assessment and preparation are necessary. Intraoperatively, bilateral rupture
of the bullae could be catastrophic and preparations should be made for this possibility. In order to diminish this risk,
a surgical technique including preemptive collapse of the bulla by minithoracotomy and tube drainage, with use of a bronchial
blocker to the affected part of the lung may be used. If rupture occurs, then high frequency jet ventilation may be effective.
Use of a double lumen endobronchial tube may be advantageous for patients with either unilateral and bilateral bullae. Anaesthesia
for patients with bullae should avoid positive-pressure ventilation and nitrous oxide in order to limit the risk of barotrauma
from a ball valve mechanism. In this case, the risk of barotrauma was reduced by performing an inhalational induction of anaesthesia
and limiting peak inflation pressures during thoracotomy. It was elected to use positivepressure ventilation through a double
lumen endobronchial tube following chest incision. A high frequency jet ventilator was available but not employed. Anaesthetic
management was complicated by the presence of pleural adhesions, surgical approach directly through a bulla, and the requirement
for one lung ventilation.
The de i’aone descendante aecouverte cnez un pattent porde grosses bulles bilatérales d’emphysème est discutée, esthésie habituelle
pour une chirurgie de l’aorte descendante site une ventilation mécanique unilatérale et constitue ainsi sque additionnel pour
le porteur de bulles emphysémas bilatérales. Ces patients ont ordinairement des affections onaires graves et l’évaluation
et la préparation préopéraprennent une importance spéciale. Pendant l’intervention, pture de bulles bilatérales peut être
catastrophique et il se préparer à cette éventualité. Pour minimiser ce risque, technique chirurgicale qui inclut le collapsus
préventif de lle par minithoracotomie et drainage, avec installation d’un ieur bronchique sur la partie atteinte du poumon.
Si une re survient, le passage à la ventilation par jet à haute tence peut être salutaire. Le tube endobronchique à double
ère peut présenter des avantages aussi bien dans les cas ulles unilatérales que bilatérales. Chez ces patients, il vaut x
s’abstenir de ventiler avec une pression positive et du xyde d’azote afin de limiter le risque de barotraumisme soupape. Dans
ce cas-ci, on a réussi à limiter le risque arotraumatisme en réalisant une induction par inhalation réduisant la pression
d’inflation de pointe pendant la cotomie. Après l’incision thoracique, on a choisi d’utiliser tilation mécanique avec un tube
endobronchique à double ère. Un ventilateur à jet à haute fréquence était prêt mais as été utilisé. La gestion de l’anesthésie
a été compliquée par dhérences pleurales, par la rencontre d’une bulle d’emphysà l’incision et par l’obligation de ventiler
un seul poumon. 相似文献
149.
体外循环不阻断升主动脉下小儿、婴幼儿心内直视术136例分析 总被引:3,自引:2,他引:1
目的:评价体外循环下不阻断升主动脉行心内直视术对心肌的保护作用。方法:对1995年9月至1998年8月在先心心内直视术中应用此法的136例婴幼儿进行回顾性分析。全组男77例,女59例。年龄3个月~5岁(平均365±120岁),体重5~18(平均1401±352)。病种包括室间隔缺损103例,房间隔缺损12例,法乐氏四联症14例,法三2例,肺动脉瓣狭窄2例,部分性房室管通道2例,三尖瓣下移1例。结果:全组死亡3例(22%)。术后并发症:低心排2例,支气管痉挛3例,二次止血1例。结论:体外循环下不阻断升主动脉行心内直视术是临床效果满意,安全有效的心肌保护方法。 相似文献
150.
目的:探讨用于检验带膜记忆合金支架血管腔内搭桥治疗动脉瘤的模型。方法:分别以实验动物腹直肌后鞘、Dacron补片、不同口径的Dacron人血管及球囊导管材料,采用四种不同手术方法制作腹主动脉瘤模型。结果:11例动物10例模型制作成功,1例死亡,1月后造影检查发现9例的动脉瘤模型形态满意,1例动脉脉瘤扩张程度较差。结论;以腹阗甩垢鞘为材料制作动脉瘤模型具有取材方便,操作简便、不易漏血、无异物反应的优 相似文献