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61.
急性肠系膜上动脉栓塞的诊断与治疗   总被引:6,自引:1,他引:5       下载免费PDF全文
目的: 探讨急性肠系膜上动脉栓塞的诊断与治疗。方法:对近10年收治的急性肠系膜上动脉栓塞患者22例临床资料进行回顾分析。结果:术前确诊率为77.3%,2例非手术治疗者均死亡(病死率100.0%)。20例经手术治疗,其中5例行单纯坏死肠管切除,端端吻合术,3例死亡(病死率60.0%);15例行肠系膜上动脉取栓加坏死肠管切除,5例死亡(病死率33.3%)。总病死率为45.5%。结论:对于有器质性心脏病的患者,突然出现腹部疼痛,应警惕肠系膜上动脉栓塞的可能。CTA是诊断急性肠系膜上动脉栓塞的有效手段。早诊断、早期行肠系膜上动脉取栓术是提高治愈率的关键。  相似文献   
62.
一期动静脉转流与并加压破坏深静脉瓣对比的实验研究   总被引:1,自引:0,他引:1  
目的:改进一期动静脉转流术的疗效。方法:10只狗双后肢,随机选择一侧后肢行一期动静脉转流,另一侧行一期动静脉转流加水压破坏深静脉瓣。术后30天通过动脉造影进行对比研究。结果:后者能更有效地加速远段深静脉瓣的破坏,使动脉血逆行更远,同时形成更为丰富的侧枝循环,而不会增加肢体肿胀和深静脉血栓的机会。结论:一期动静脉转流加水压破坏深静脉瓣可能是治疗严重肢体缺血更为有效的方法。  相似文献   
63.
Summary Rats anaesthetised with Inactin, body temp. maintained at 37°C, were infused with mannitol-saline until both urine flow rate and conductivity reached a balanced state. In separate experiments under analogous conditions cardiac output was measured by dye dilution and organ flow rates by86Rb distribution. Doses of oxytocin of 3 ng or less, injected at or just below the carotid bifurcation, caused a highly significant natriuresis with increased tubular rejection, but no measureable haemodynamic changes. The same oxytocin dose given into the internal or external carotid artery above the bifurcation caused neither haemodynamic changes nor natriuresis. Injection of vasopressin, angiotensin and -MSH at the sensitive site did not result in natriuresis in the same dosage range. Section of the sinus nerve significantly decreased the natriuretic response to oxytocin. It is suggested that the carotid body contains a specific oxytocin receptor capable of eliciting natriuresis in the rat.  相似文献   
64.
Summary Three-dimensional arteriography was used to analyse the arterial supply of the great and second toes of 100 cadaveric feet down to the microsurgical level. This information will aid in successful composite tissue transfers of these toes to the hand. The arterial blood supply of the great toe came principally from the first dorsal metatarsal a. (78%) and the first plantar metatarsal a. (22%), and secondarily from the medial tarsal aa. and the three terminal branches of the medial plantar a. For the second toe, the first dorsal metatarsal a. (78%) and the first plantar metatarsal a. (22%) supplied blood from the medial side, and the second dorsal metatarsal a. (78%) and the second plantar metatarsal a. (22%) supplied blood from the lateral side. Seven arterial patterns were found in the interdigital web space. The socalled general pattern was seen in the first web space in 65% of the feet examined. In the second web space it was found in 85%. The first intermetatarsal space sometimes contained a large artery arising directly from the dorsalis pedis or first proximal perforating a. as well as the first dorsal and first plantar metatarsal arteries. In this space, arterial patterns were classified into 4 types and 9 subtypes based on the origins and proximal courses of these arteries. The so-called standard pattern was found in only 19% of the feet, while an arterial pattern with a common proximal trunk on the plantar side for the first dorsal and first plantar metatarsal aa. was found most frequently (46%). In the second intermetatarsal space the second dorsal metatarsal a. was usually located on the dorsum.
Les artères de l'hallux et du deuxième orteil. Analyse tridimensionnelle de cent pieds de cadavres
Résumé L'artériographie en trois dimensions a été utilisée pour analyser la vascularisation artérielle de l'hallux et du deuxième orteil de cent pieds de cadavres jusqu'au niveau microchirurgical. Ces renseignements aideront au succès des transferts de tissus composites de ces orteils vers la main. La vascularisation artérielle de l'hallux vient principalement de la première artère métatarsienne dorsale (78 %) et de la première artère métatarsienne plantaire (22 %) et secondairement des artères tarsiennes médiales et des trois branches terminales de l'artère plantaire médiale. Pour le deuxième orteil, la première artère métatarsienne dorsale (78 %) et la première artère métatarsienne plantaire (22 %) vascularisent le versant médial, la deuxième artère métatarsienne dorsale (78 %) et la deuxième artère métatarsienne plantaire (22 %) vascularisent le versant latéral. Sept dispositions artérielles ont été trouvées dans la commissure interdigitale. Une disposition dénommée commune a été vue dans la premiere commissure sur 65 % des pieds examinés, dans la deuxième commissure dans 85 % des cas. Le premier espace intermétatarsien contient parfois une volumineuse artère, naissant directement de l'artère dorsale du pied ou de la première artère perforante proximale, mais aussi des premières artères métatarsiennes dorsale ou plantaire. Dans cet espace, les dispositions artérielles sont classées en 4 types et 9 sous-types, basés sur l'origine et le trajet proximal de ces artères. La disposition standard a été trouvée seulement sur 19 % des pieds, alors qu'une disposition comprenant un tronc proximal commun situé sur le versant plantaire, fournissant les premières artères métatarsiennes dorsale et plantaire, a été trouvée plus fréquemment (46 %). Dans le deuxième espace intermétatarsien, la deuxième artère métatarsienne dorsale était habituellement située sur le versant dorsal.
  相似文献   
65.
目的:利用高脂饮食加空气干燥术建立一种稳定、重复性好、有较典型动脉粥样硬化病理改变的动物模型。方法:32只日本大耳白兔随机分为模型组(n=24)、对照组(n=8)。模型组给予高脂饲料喂养加空气干燥术,术中结扎左侧颈动脉分支血管,对照组正常饲料喂养,分别于术后第2、4、8、12周处死动物。取颈动脉组织切片HE染色,光镜下观察。结果:(1)75%兔颈总动脉存在细小血管分支,暂时结扎侧支血管后干燥效果更好。(2)对双侧颈动脉实施手术,结扎左侧分支,成模率更高。部分斑块显示出不稳定性。结论:采用改进后高脂饮食加空气干燥术可成功建立兔颈动脉粥样硬化模型,其病理特点适合于目前临床研究。  相似文献   
66.
研究轴向应变对血管顺应性的影响 ,明确能否通过调节吻合张力建立顺应性一致的静脉移植修复动脉缺损模型。取一段做完轴向拉伸实验的血管 (兔股动、静脉分别为 13、12条 ) ,测量不同伸长率下的压力—容积曲线 ,换算为压力—标准容积曲线 ,用幂函数 P=M1 × [еM2 ( v- v0 ) - 1]进行拟合 ,用多项式 M=a1 λ5+a2 λ4 +a3λ3+aλ2 +a5λ+a6 拟合 M- λ数据。由 P=M1 × [еM2 ( v- v0 ) - 1]得出在动脉平均压 (11.78KPa)下血管顺应性 dv/ dp=1/ (M1 ×M2 +11.78M2 )。由张力 T与伸长率 λ的单值对应关系建立起 T与顺应性 dv/ dp的单值对应关系 ,发现在张力 1.19g时 ,在动脉平均压下 ,动静脉的顺应性一致 ,为 0 .0 31,其所对应的动静脉伸长率为 :1.6 7及 1.32  相似文献   
67.
Summary The human fetal carotid body was studied using both histochemical and electron microscopic methods. The glomus cells of a mid term fetal carotid body evidently contain catecholamines. This was demonstrated both by formaldehyder-induced fluorescence of the cells and by the presence of typical dense-cored vesicles (diameter 1430–3200 Å) in the cytoplasm of the chief cells. The glomus cells were densely innervated and the synapses found on their surface were probably cholinergic in type, containing agranular synaptic vesicles measuring 400–700 Å in diameter with a few dense-cored vesicles measuring 900 to 1300 Å. Synapses were not found in any other cell type within the glomus caroticum. The prominent feature of the glomus cell cytoplasm was the presence of the dense-cored vesicles. The density of the vesicular core varied only slightly from cell to cell. There were no perceptible differences in vesicular size between the different cells. The glomus cells were mostly surrounded by the processes of the sustentacular cells, which usually also surrounded the capillary walls. No glomus cells were ever found in direct contact with the capillary wall. The capillaries were wide and very numerous over the restricted area of the organ. They formed sinusoidal loops, probably anastomosing with each other. Finally, the features of the fine structure are discussed, correlating the present findings with our knowledge about the adult functional carotic body.  相似文献   
68.
An in vivo model has been developed for chronic observation of the effects of ischemia on cortical bone remodeling and perfused vascularity. Diaphragm occluders were implanted around the right common iliac artery of four rabbits and inflated to produce 10 h of ischemia to the limb. Microcirculation was monitored with intravital microscopy of injected fluorescent microspheres and FITC-Dextran 70 through a bone window, the tibial bone chamber implant (BCI). Bone resorption and apposition in the BCI were indicated with mineralization dyes. Between 2 and 12 h following release of the occluder, secondary ischemia/no-reflow and other evidence of reperfusion injury were observed. Vessel damage was suggested by abnormally high leakage of FITC-D70 from the few vessels perfused during secondary ischemia. In the weeks following occluder release perfused vasculature increased beyond pre-occlusion levels. Net bone resorption reached a maximum when vascularity passed normal levels. In order to further validate the arterial occlusion model for osteonecrosis, techniques for (1) confirming bone death and (2) detecting increased leukocyte adherence to endothelial cells were added. The dead cell stain Ethidium homodimer-1 was used to tag dead osteocytes immediately after occlusion and produced a measure designated osteonecrosis index. To detect leukocytes adhering to vessel walls, carboxyfluorescein diacetate, succinimidyl ester was injected at occluder release. An increase in the number of adherent leukocytes was detected. © 1999 Biomedical Engineering Society. PAC99: 8764Rr, 8717-d, 8719Tt  相似文献   
69.
3D MRI-Based Multicomponent FSI Models for Atherosclerotic Plaques   总被引:1,自引:0,他引:1  
A three-dimensional (3D) MRI-based computational model with multicomponent plaque structure and fluid-structure interactions (FSI) is introduced to perform mechanical analysis for human atherosclerotic plaques and identify critical flow and stress/strain conditions which may be related to plaque rupture. Three-dimensional geometry of a human carotid plaque was reconstructed from 3D MR images and computational mesh was generated using Visualization Toolkit. Both the artery wall and the plaque components were assumed to be hyperelastic, isotropic, incompressible, and homogeneous. The flow was assumed to be laminar, Newtonian, viscous, and incompressible. The fully coupled fluid and structure models were solved by ADINA, a well-tested finite element package. Results from two-dimensional (2D) and 3D models, based on ex vivo MRI and histological images (HI), with different component sizes and plaque cap thickness, under different pressure and axial stretch conditions, were obtained and compared. Our results indicate that large lipid pools and thin plaque caps are associated with both extreme maximum (stretch) and minimum (compression when negative) stress/strain levels. Large cyclic stress/strain variations in the plaque under pulsating pressure were observed which may lead to artery fatigue and possible plaque rupture. Large-scale patient studies are needed to validate the computational findings for possible plaque vulnerability assessment and rupture predictions.  相似文献   
70.
目的 探讨寰椎因素致椎 基底动脉供血不足的发病机制及手术切开横突孔减压提供解剖学依据。方法 在5 0例中国成年人干燥寰椎标本上 ,对具有临床意义的数据进行解剖学测量。结果 寰椎横突孔与椎动脉沟的成角左侧为(6 7 87± 5 39)°,右侧为 (6 9 84± 4 5 5 )° ;椎动脉沟绕寰椎侧块成角 :左侧为 (6 2 4 6± 4 6 6 )°,右侧为 (6 3 6 1± 2 31)°。寰椎横突孔前壁厚度 :左侧为 (2 96± 0 5 4 )mm ,右侧为 (3 2 1± 0 4 0 )mm。横突孔后壁厚度 :左侧为 (2 2 8± 0 5 7)mm ,右侧为 (2 0 2± 0 2 6 )mm。以上数据左、右侧比较差异无显著性。结论 椎动脉行经在寰椎横突孔与椎动脉沟内时 ,在骨性结构上有明显的两个成角 ,即横突孔与椎动脉沟的成角和椎动脉沟绕过侧块的成角 ,椎动脉的这两个成角增加了血液循环的阻力 ,同时在头颈部旋转运动时 ,椎动脉与骨性成角间更加贴近 ,这两个成角与椎 基底动脉供血不足的发生有关。寰椎横突孔后壁较前壁薄 ,此数据可作炒寰椎横突孔后壁切开减压时手术参考依据  相似文献   
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