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61.
The capability of magnetic resonance (MR) imaging for detecting aortic, iliac, and femoral stenoses and occlusions was evaluated. Multisection spin-echo studies at 0.35 tesla were obtained of the infrarenal aorta to the femoral bifurcation in 24 patients, all of whom had undergone intraarterial angiography within 14 days of imaging. Transaxial MR images were compared with the angiograms. Arterial stenoses and occlusions in these vessels detected by MR imaging correlated with angiographic findings in 91% of the instances. Protrusional atherosclerotic plaques and occlusions and stenoses in the aortoiliac region were demonstrated accurately on MR images; complications of previous vascular surgery, such as aneurysms at sites of previous anastomoses or endarterectomy, were also identified. Due to the limited spatial resolution, MR images failed to demonstrate some femoral stenoses. MR imaging may be used for evaluation of aortoiliac vascular disease and for follow-up study after surgical revascularization. However, the limited spatial resolution, noncomposite display of the aortoiliofemoral circulation, and lack of evaluation of peripheral runoff provided by current MR imaging techniques militate against its replacing angiography prior to vascular intervention. 相似文献
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Primary cavitating lung carcinomas have not previously been described with spontaneous pneumothorax as the presenting manifestation. Two patients whose pneumothoraces resulted in the initial diagnosis of a primary cavitary lung carcinoma are described. Pathologic evidence of vascular invasion suggests tumor necrosis with secondary rupture into the pleural space as a likely mechanism for pneumothorax. 相似文献
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López-Menchero R del Pozo C Andreo L Sánchez L Albero MD Alvarez L Pinar A 《Nefrología : publicación oficial de la Sociedad Espa?ola Nefrologia》2006,26(6):711-718
We report a retrospective study on the results of 132 native fistulas, 12 grafts and 27 tunneled catheters followed during 30 months in 144 patients on hemodialysis. The results were compared according to patient age: 75 years or over (n = 58, 80.3 +/- 3.5) vs below 75 years (n = 86, 59.5 +/- 13.3). Gender, presence of diabetes and type of fistula were also included in the analysis. RESULTS: There were no statistically significant differences between both groups in the use of tunneled catheters or grafts (8.6% vs 5.8% y 5.2% vs 10.5% respectively), primary failure of native fistulas (7.1% in those aged 75 years or over vs 25.5% in patients below 75 years), rate of thrombosis (0.03 vs 0.09/patient year at risk respectively) or number of percutaneous or surgical procedures in order to maintain the fistula patency (0.11 vs 0.16/patient year at risk respectively). At the same time no differences were seen in the primary, primary assisted and secondary patency of the native fistulas. The mean age of the patients when the first access fistula was created was different according to the area of surgery (74.9 +/- 9.3 for the elbow vs 64.9 +/- 16.2 years for the forearm, p < 0.005). Diabetes was an unfavourable factor for primary (HR Cox 2.08, p < 0.05) or secondary (Log Rank, p <0.05) patency. CONCLUSION: The vascular access for hemodialysis in elderly patients presents a similar evolution to that seen in younger populations if the access creation is based on an exhaustive study, including ecodoppler of the vascular map and the use of more proximal fistulas if necessary. Therefore the more frequent use of grafts or catheters in elderly patients is not justified. 相似文献
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AM Innes KM Boycott EG Puffenberger D Redl IM MacDonald AE Chudley C Beaulieu R Perrier T Gillan A Wade JS Parboosingh 《Clinical genetics》2010,78(5):424-431
Innes AM, Boycott KM, Puffenberger EG, Redl D, MacDonald IM, Chudley AE, Beaulieu C, Perrier R, Gillan T, Wade A, Parboosingh JS. A founder mutation in BBS2 is responsible for Bardet‐Biedl syndrome in the Hutterite population: utility of SNP arrays in genetically heterogeneous disorders. Bardet‐Biedl syndrome (BBS) is a multisystem genetically heterogeneous disorder, the clinical features of which are largely the consequence of ciliary dysfunction. BBS is typically inherited in an autosomal recessive fashion, and mutations in at least 14 genes have been identified. Here, we report the identification of a founder mutation in the BBS2 gene as the cause for the increased incidence of this developmental disorder in the Hutterite population. To ascertain the Hutterite BBS locus, we performed a genome‐wide single nucleotide polymorphism (SNP) analysis on a single patient and his three unaffected siblings from a Hutterite family. The analysis identified two large SNP blocks that were homozygous in the patient but not in his unaffected siblings, one of these regions contained the BBS2 gene. Sequence analysis and subsequent RNA studies identified and confirmed a novel splice site mutation, c.472‐2A>G, in BBS2. This mutation was also found in homozygous form in three subsequently studied Hutterite BBS patients from two different leuts, confirming that this is a founder mutation in the Hutterite population. Further studies are required to determine the frequency of this mutation and its role, if any, in the expression of other ciliopathies in this population. 相似文献
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