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Successful reoperation of a ruptured aortic arch aneurysm in a patient with Takayasu's disease. Takayasu's disease is an inflammatory arteriopathy that often progresses to stenosis or aneurysms of the large arteries of the aortic arch. In this connection aneurysms of the ascending aorta are rare. We report the case of a 33 years old female with a ruptured aneurysm of the ascending aorta complicated by a former operation of a truncobicarotidal bypass and severe sclerosis. After ascending aorta and aortic arch replacement was performed in deep hypothermia circulatory arrest we could discharge the patient in good condition on the 11. postoperative day.  相似文献   
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BACKGROUND AND OBJECTIVES: In Italy, the prevalence of C282Y is lower than in Northern European countries. We hypothesized a higher prevalence of C282Y in Northern than in Southern Italian populations. We previously identified a nonsense mutation (E168X) in hemochromatosis probands originating from a region in the north-west of Italy. We aimed to define the prevalence of C282Y and E168X in that region and the origin of the E168X mutation by haplotype analysis. DESIGN AND METHODS: Six-hundred and six blood donors were investigated for C282Y, H63D, S65C and E168X mutations by polymerase chain reaction (PCR)-restriction assays. Three hundred were also tested for rare HFE and TFR2 mutations by reverse-hybridization test strips. D6S265, D6S105 and D6S1281 microsatellites were analyzed to define E168X 6p-associated haplotypes. RESULTS: One C282Y homozygote, thirteen C282Y/ H63D compound heterozygotes, four E168X heterozygotes and three E168X/H63D compound heterozygotes were found. The allele frequencies of C282Y, H63D, S65C, and E168X were 4.7%, 14.9%, 0.74% and 0.58%, respectively. INTERPRETATION AND CONCLUSIONS: The prevalence of C282Y in the region investigated was much higher than that previously reported in Italy. This finding is probably due to the heavy Celtic component of this north-western population and suggests that in populations of Northern Italian descent screening studies for hemochromatosis could be cost-effective. The prevalence of E168X in this region, although low, suggests that the mutation probably originated here many years ago and its frequency increased as a result of a local founder effect. Given its severity, we suggest that the E168X mutation should be searched for in all hemochromatosis patients of Northern ancestry with an incomplete HFE genotype.  相似文献   
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PURPOSE: To determine the efficacy of antiplatelet or anti-coagulant therapy in preventing graft occlusions after coronary artery bypass surgery. DATA IDENTIFICATION: Studies published from 1966 to 1988 were identified through a computerized search using MEDLINE, by searching the bibliographies of all identified articles, and by consulting with the cardiologists and cardiothoracic surgeons in the Veterans Administration Cooperative Study Group on Antiplatelet Therapy After Coronary Artery Bypass Surgery. STUDY SELECTION: All studies selected were randomized, controlled clinical trials comparing at least one active drug with a placebo or nonplacebo control group. DATA EXTRACTION: Key data were extracted from each article, including the percentage of patients in each treatment group with one or more grafts occluded, the percentage of patients with completed postoperative catheterizations, timing of postoperative catheterization, and timing of start of treatment. These data were easily obtained from each article and did not require multiple observers. RESULTS OF DATA ANALYSIS: All studies had positive treatment-effect sizes in favor of active treatment, although some studies did not achieve statistical significance. A meta-analysis combining all treatment effects clearly shows that active treatment is beneficial (overall effect size = 0.30; CI, 0.21 to 0.38). Efficacy improves with early initiation of treatment. CONCLUSIONS: Early initiation of antiplatelet or anticoagulant drugs reduces the incidence of graft occlusions after coronary artery bypass surgery.  相似文献   
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BACKGROUND AND AIM OF THE STUDY: Mitral valve reconstruction in patients with acute endocarditis (AE) is a challenging operation which prompts the surgeon into immediate action. This report summarizes the mid-term results of 22 patients who required mitral valve reconstruction due to AE. METHODS: Mean patient age was 46 years (range: 20-79 years); mean follow up was 46 months (range: 1-90 months). Preoperatively, >70% of patients had severe mitral regurgitation and were in NYHA functional class III. Surgical techniques used were annuloplasty (n = 16; 10 with Carpentier ring, five Wooler-Kay and one Frater); suture closure of the perforation (n = 1), patch closure of the perforation (n = 5), leaflet resection with primary closure (n = 2), leaflet resection with patch closure (n = 8), and chordal transfer (n = 3). Additional surgery included CABG (n = 3) and De Vega plasty (n = 4). Aortic valve replacement or reconstruction (n = 9) included one mechanical valve, one bioprosthesis, one reconstruction and six homografts. Patients were followed up annually in our outpatient department and/or by questionnaires. RESULTS: Two patients died perioperatively due to either low output syndrome or uncontrolled sepsis. There were three reoperations; two of these were successful, and one patient subsequently died. In addition, one patient died six years after operation due to prostatic cancer, and one seven years later due to progressive heart failure. At the last follow up, 15 patients were in NYHA class I (68%) and five in class II (23%); no or only mild mitral insufficiency was seen on transthoracic echocardiography (91%). The estimated survival rate at 60 months was 87 +/- 12.7%, and 12 patients were followed up for >60 months. No incidence of recurrent valve infection occurred. CONCLUSION: Mitral valve reconstruction in patients with AE shows a low incidence of valve-related complications with promising postoperative functional results and mid-term survival. On this basis, mitral valve reconstruction for mitral insufficiency secondary to AE may be recommended as a valve salvage treatment, when it is technically possible.  相似文献   
109.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited myocardial disease that predominantly affects the right ventricle and is associated with ventricular arrhythmias that may lead to sudden cardiac death. Mutations within at least seven separate genes have been identified to cause ARVC, however a genetic culprit remains elusive in approximately 50% of cases. Although negative genetic testing may be secondary to pathogenic mutations within undiscovered genes, an alternative explanation may be the presence of large deletions or duplications involving known genes. These large copy number variants may not be detected with standard clinical genetic testing which is presently limited to direct DNA sequencing. We describe two cases of ARVC possessing large deletions involving plakophilin‐2 (PKP2) identified with microarray analysis and/or multiplex ligation‐dependent probe amplification (MLPA) that would have been classified as genotype negative with standard clinical genetic testing. A deletion of the entire coding region of PKP2 excluding exon 1 was identified in patient 1 and his son. In patient 2, MLPA analysis of PKP2 revealed deletion of the entire gene with subsequent microarray analysis demonstrating a de novo 7.9 Mb deletion of chromosome 12p12.1p11.1. These findings support screening for large copy number variants in clinically suspected ARVC cases without clear disease causing mutations following initial sequencing analysis.  相似文献   
110.
The high temporal resolution of EEG/MEG data offers a way to improve source reconstruction estimates which provide insight into the spatio-temporal involvement of neuronal sources in the human brain. In this work, we investigated the performance of spatio-temporal regularization (STR) in a current density approach using a systematic comparison to simple ad hoc or post hoc filtering of the data or of the reconstructed current density, respectively. For the used STR approach we implemented a frequency-specific constraint to penalize solutions outside a narrow frequency band of interest. The widely used sLORETA algorithm was adapted for STR and generally used for source reconstruction. STR and filtering approaches were evaluated with respect to spatial localization error and spatial dispersion, as well as to correlation of original and reconstructed source time courses in single source and two source scenarios with fixed source locations and oscillating source waveforms. We used extensive computer simulations and tested all algorithms with different parameter settings (noise levels and regularization parameters) for EEG data. To verify our results, we also used data from MEG phantom measurements. For the investigated scenarios, we did not find any evidence that STR-based methods outperform purely spatial algorithms applied to temporally filtered data. Furthermore, the results show very clearly that the performance of STR depends very much on the choice of regularization parameters.  相似文献   
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