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41.
Ruptures of the hepatic artery and hepatic pseudoaneurysms (PA) are rare but serious complications of hepatic transplantation. We conducted a retrospective study of 640 liver transplantations performed in our institution for a variety of pathologies. After surgery, seven major arterial bleeds occurred (0.9%). Of these seven cases, there were due to hepatic artery rupture (HAr) and four to PA rupture; all confirmed at either surgery (six cases) or autopsy (one case). Five of the seven patients died. In all cases the transplantation was difficult. All vascular injuries but one were caused by sepsis and occurred either after an undetermined cause septicemic syndrome (five cases) or graft dysfunction (one case). The last vascular injury was biliary drainage related. Six of the seven patients had imaging studies. Sonography (five cases) found a sub-hepatic hypoechoic collection in three cases but failed to do so in two. Duplex doppler (three cases) failed in all three cases to demonstrate a PA. Computed tomography (three cases) showed one PA, one perihilar sub-hepatic collection and failed in one. Conventional angiography (three cases) depicted a PA in all three cases. At the present time, our practice is to perform systematic angiography in patients with undetermined cause septicemic syndrome to research a PA. And if angiography is normal, to then puncture systematically any sub-hepatic collection to determine the bacteriological nature of this collection. Correspondence to: H. Caillet  相似文献   
42.
It is shown that a repetitive pulse sequence consisting of two 90° pulses and gradients in a 1:2 ratio around the second 90° pulse generates interscan shifted stimulated echoes (SSTEs) and intrascan multiple spin echoes (MSEs). Separation of these two types of signals is accomplished using specific gradient crusher schemes. The intensity of the SSTEs is an order of magnitude larger than that of the MSEs and determines the signal contrast if both effects are selected simultaneously. The SSTE sequence generates improved contrast between gray and white matter, even at high field, which is explained in terms of increased inverse T1-weighting for the interscan echo. The MSE image has low signal to noise and no detectable contrast. The effect of interscan diffusion weighting is also discussed.  相似文献   
43.
距骨的血液供应及其临床意义   总被引:30,自引:0,他引:30  
本文观察了24侧尸体足标本,均无已知临床血管疾病。在死后36~48小时之间行动脉灌注ABS填充剂,以化学腐蚀和手工剔除的方法清除软组织。距骨的血供来自小腿下部三根主要动脉的分支,即跗骨管动脉和三角支、近端和远端跗骨窦动脉、颈上支及后结节血管丛。跗骨管动脉常发自足底内侧动脉,而三角支多单独自胫后动脉发出;跗骨管动脉通常比三角支和跗骨窦动脉都来得细小。以上的这些动脉相互吻合,形成了一个骨膜血管网,覆盖于全部的距骨非关节面上。而且,环绕着跗骨管、跗骨窦、距骨颈的上面和距骨体部的内侧面,由三角支、跗骨管动脉、跗骨窦动脉、颈上支及其相互之间的吻合血管网形成了一个不定形的距骨动脉环。本文还讨论了距骨缺血性坏死与动脉环的可能关系,距骨骨折脱位或手术后的缺血性坏死是由于距骨动脉环的毁损或功能受影响所致。三角支在距骨骨折脱位时具有重要意义,手术或手法复位时应注意保护。  相似文献   
44.
山东农村儿童膳食中人体锌吸收率的测定   总被引:1,自引:0,他引:1  
目的:测定山东农村儿童代表性膳食中锌(Zn)的人体吸收率。方法:模拟山东农村典型膳食模式,采用富集的天然低丰度稳定性同位素67Zn标记ZnCl2,使用热电离质谱法(TIMS)检测膳食和粪便中总锌含量与67Zn/68Zn比值,计算锌的真吸收率;使用原子吸收分光光度计穴AAS雪测定膳食与粪便的总锌,计算锌的表观吸收率。同时测定影响锌吸收的因子膳食脂肪、蛋白、植酸、纤维素和维生素C(Vc)的含量,计算日平均摄入量,将其结果与我国儿童每日推荐膳食营养素摄入量(RNIs)进行比较。结果:锌的真吸收率为(12.94±3.32)%,锌的表观吸收率为(22.37±1.59)%,两者差异有统计学意义(P<0.05)。锌的平均日摄入量为11.16mg,占RNI的111.6%,高于推荐量。蛋白质和Vc的日摄入量分别为31.2g与13.3mg,占RNIs的56.73%和29.60%,低于推荐量。脂肪、植酸和膳食纤维的日摄入量较高。结论:在蛋白质和Vc的日摄入量较低,脂肪、植酸和膳食纤维的日摄入量较高的条件下,锌的真吸收率较低。  相似文献   
45.
动脉硬化性脑白质病的CT表现与临床分析   总被引:1,自引:0,他引:1  
目的 :探讨动脉硬化性脑白质病的临床与CT表现特点。方法 :收集 10 0例动脉硬化性脑白质病的临床与CT资料进行综合分析。结果 :10 0例的CT表现为 :弥漫性脑白质低密度改变 ,主要分布在双侧脑室旁及半卵圆中心白质区 ,病灶多呈条带状及月晕状。合并脑萎缩 90例 ;脑梗塞 76例 ,其中 2 5例有大的梗塞灶 ,其余为腔隙性梗塞 ;脑出血 9例 ,其中位于壳核 5例 ,丘脑 3例 ,小脑 1例 ;有 15例伴发基底节区软化灶。增强扫描 8例 ,显示病灶无明显增强。结论 :动脉硬化性脑白质病是发生于老年人的缺血性脑血管病 ,高血压动脉硬化是其主要发病因素。  相似文献   
46.
A variety of continuous and pulsed arterial spin labeling (ASL) perfusion MRI techniques have been demonstrated in recent years. One of the reasons these methods are still not routinely used is the limited extent of the imaging region. Of the ASL methods proposed to date, continuous ASL (CASL) with a separate labeling coil is particularly attractive for whole-brain studies at high fields. This approach can provide an increased signal-to-noise ratio (SNR) in perfusion images because there are no magnetization transfer (MT) effects, and lessen concerns regarding RF power deposition at high field because it uses a local labeling coil. In this work, we demonstrate CASL whole-brain quantitative perfusion imaging at 3.0 T using a combination of strategies: 3D volume acquisition, background tissue signal suppression, and a separate labeling coil. The results show that this approach can be used to acquire perfusion images in all brain regions with good sensitivity. Further, it is shown that the method can be performed safely on humans without exceeding the current RF power deposition limits. The current method can be extended to higher fields, and further improved by the use of multiple receiver coils and parallel imaging techniques to reduce scan time or provide increased resolution.  相似文献   
47.
48.
本文报道1000例正常人发自由基的电子自旋共振波谱饱和功率(ESR-SP)的检测结果。所得正常值的全组中位数为2.496mw;95%上下限分别为2.989及1.720mw。如按性别统计,则女性下限(1.617mw)较男性(1.983mw)为低,(P<0.05)。按年龄分别统计,则40岁以上的中位数(2.376mw)及其下限(2.009mw)高于40岁以下的中位数(2.548mw)及其下限(1.597mw),两者差异有显著性(P<0.05)及极显著性(P<0.01)。因此在使用此正常值指标时,必须注意性别与年龄因素。  相似文献   
49.
We examined 161 human tissue samples using the spot hybridization technique with nonradioactive labeled DNA probes of human papillomavirus (HPV). Whole cells were spotted on nitrocellulose filters; DNA of the cells was denatured and fixed to the filter. Then the DNA spots were hybridized to nonradioactive labeled DNA and monitored by a sandwich immunoenzymatic reaction. This technique is simple, sensitive, specific, requires no special equipment, and can be used in clinical settings. HPV DNA was found in 92% of samples in which, on the basis of histologic and colposcopic criteria, its presence was suspected, as well as in 31 samples where it was not suspected.  相似文献   
50.
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