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91.
92.
Carotid endarterectomy still represents the gold standard treatment of carotid artery bifurcation stenosis but percutaneous angioplasty with stenting is rapidly growing as a non-invasive alternative. In this paper we report the results of systematic application of carotid stenting performed in a cardiological setting, particularly as regards clinical management of patients and technical approach. One-hundred (100) procedures of carotid artery stenting (CAS) on 94 consecutive patients, both symptomatic and asymptomatic, with a carotid stenosis > 70%, were performed over a period of 30 months. The technical approach was directly derived from coronary angioplasty with use of large lumen guiding catheters, 0.014 in. intravascular guidewires and distal protection devices usually employed in coronary interventions. In 3 cases, a post-carotid endarterectomy restenosis and in 97 cases, a de-novo lesion, were treated respectively; in 71 cases, the degree of stenosis was 71-89% and in 29 cases, 90-99%. Cerebral protection was obtained with a distal to the lesion endovascular filter in 63 cases. Immediate technical success, i.e. residual stenosis of the treated vessel < 30% and no significant pathologic acceleration of blood flow (< 1.5 m/sec) at the Doppler ultrasound evaluation, was achieved in all procedures (100%). Ninety-six (96) procedures were totally uncomplicated; in-hospital cerebral complications were 1 TIA, 2 minor and 1 major strokes; at 30-day follow-up one additional major stroke occurred. Despite a particularly high incidence of comorbidities, neither unfavorable cardiological complications nor neurologic deaths were reported. Systematic CAS is a feasible treatment of the carotid artery bifurcation stenosis with high procedural success and low perioperative and short term complications. Its performance in a cardiological setting can combine satisfying procedural results and potentially successful handling of cardiovascular complications.  相似文献   
93.
OBJECTIVES: The aim of this study was to evaluate whether the occurrence of the Brugada Syndrome typical electrocardiogram (ECG) pattern (i.e., right bundle branch block, coved-type ST-segment elevation, and T-wave inversion in the right precordial leads) is characterized by a concomitant lengthening of QT intervals in the right precordial leads. BACKGROUND: It has been suggested that the typical ECG pattern of Brugada syndrome is due to a decreased net inward current during phase 1 of the action potential, which also leads to its prolongation in the right epicardium. METHODS: Thirty-two subjects (19 males) age 37 +/- 15 years with a suspicious baseline ECG, or who were relatives of Brugada syndrome patients, underwent 12-lead ECG before and after the administration of flecainide. RESULTS: The flecainide test was negative in 14 and positive in 18 subjects. After flecainide administration, the positive ECGs were characterized by a greater QT interval corrected for heart rate (QTc) prolongation in the right precordial leads than that in the negative ECGs (78.2 +/- 35.5 ms vs. 22.0 +/- 28.4 ms in V(1) and 107.1 +/- 43.8 ms vs. 26.7 +/- 30.1 ms in V(2); p < 0.01), whereas there was no difference in the QTc prolongation in the left precordial leads (55.2 +/- 25.3 ms vs. 35.1 +/- 28.1 ms in V(5) and 53.1 +/- 32.8 ms vs. 27.3 +/- 22.4 ms in V(6); p = NS). CONCLUSIONS: In accordance with the electrophysiological background, the typical ECG pattern of Brugada syndrome is also characterized by a considerable prolongation of the QT interval in right precordial leads.  相似文献   
94.
BACKGROUND: Moderate alcohol consumption has been associated in several studies with decreased risk of cardiovascular and cerebrovascular events; however, available data on the effects of alcohol intake on cognitive functioning are conflicting. We assessed the association between alcohol consumption and cognitive impairment in a series of older subjects enrolled in a multicenter pharmacoepidemiology survey. METHODS: The association between average alcoholic intake and cognitive performance was assessed in 15,807 patients admitted to participating centers during the survey periods. Demographic variables, comorbid conditions, medications, and objective tests that were associated with cognitive impairment (as indicated by a Hodkinson Abbreviated Mental Test score <7) in separate logistical regression models were examined as potential confounders in a summary model. RESULTS: Cognitive impairment was detected in 1693 (19%) of 8755 drinkers and 2008 (29%) of 7052 nondrinkers (Fisher's exact test, p < 0.0001). After adjusting for potential confounders, alcohol consumption was associated with decreased probability of cognitive impairment (odds ratio, 0.75; 95% confidence interval, 0.66-0.85). The relationship between drinking level and cognitive dysfunction was nonlinear, because the probability of cognitive impairment was decreased for moderate alcohol use as compared with abstinence, but it was increased for daily consumption exceeding one wine-equivalent liter among men and 0.5 liter among women. This nonlinear association persisted when cerebrovascular and Alzheimer's disease were considered separately. CONCLUSIONS: Alcohol abuse is associated with increased prevalence of cognitive dysfunction among older subjects; however, a daily alcohol consumption of less than 40 g for women and 80 g or less for men might be associated with a decreased probability of cognitive impairment. This possible protective effect of alcohol consumption should be further assessed by prospective studies.  相似文献   
95.
ObjectivesThe aim of this study was to define predictors of prosthesis-patient mismatch (PPM) and its impact on mortality after transcatheter aortic valve replacement (TAVR) with self-expandable valves (SEVs) in patients with small annuli.BackgroundTAVR seems to reduce the risk for PPM compared with surgical aortic valve replacement, especially in patients with small aortic annuli. Nevertheless, predictors and impact of PPM in this population have not been clarified yet.MethodsPredictors of PPM and all-cause mortality were investigated using multivariable logistic regression analysis from the cohort of the TAVI-SMALL (International Multicenter Registry to Evaluate the Performance of Self-Expandable Valves in Small Aortic Annuli) registry, which included patients with severe aortic stenosis and small annuli (annular perimeter <72 mm or area <400 mm2 on computed tomography) treated with transcatheter SEVs: 445 patients with (n = 129) and without (n = 316) PPM were enrolled.ResultsIntra-annular valves conferred increased risk for PPM (odds ratio [OR]: 2.36; 95% confidence interval [CI]: 1.16 to 4.81), while post-dilation (OR: 0.46; 95% CI: 0.25–0.84) and valve oversizing (OR: 0.53; 95% CI: 0.28–1.00) seemed to protect against PPM occurrence. At a median follow-up of 354 days, patients with severe PPM, but not those with moderate PPM, had a higher all-cause mortality rate compared with those without PPM (log-rank p = 0.008). Multivariable Cox regression confirmed severe PPM as an independent predictor of all-cause mortality (hazard ratio: 4.27; 95% CI: 1.34 to 13.6).ConclusionsAmong patients with aortic stenosis and small aortic annuli undergoing transcatheter SEV implantation, use of intra-annular valves yielded higher risk for PPM; conversely, post-dilation and valve oversizing protected against PPM occurrence. Severe PPM was independently associated with all-cause mortality.  相似文献   
96.
OBJECTIVE: Antineutrophil cytoplasmic antibodies (ANCA) binding to neutrophil elastase (NE) and proteinase 3 (PR3) are detectable in most patients with cocaine-induced midline destructive lesions (CIMDL), but the pathogenic role and antigen specificity of these antibodies are unknown. This study was undertaken to assess the effects of NE ANCA on the enzymatic activity of NE, to determine whether these antibodies interfere with the physiologic effect of secretory leukoprotease inhibitor (SLPI), and to investigate the antigen specificity of both NE and PR3 ANCA in patients with CIMDL. We also compared the binding of PR3 ANCA in patients with CIMDL with that in patients with Wegener's granulomatosis (WG). METHODS: PR3 ANCA and NE ANCA were detected by capture enzyme-linked immunosorbent assays (ELISAs) and by indirect immunofluorescence. IgG was purified from the patients' sera, and the influence of NE ANCA on the enzymatic activity of NE and on the inhibitory activity of SLPI was investigated by determining the hydrolysis of N-methoxysuccinyl-Ala-Ala-Pro-Val p-nitroanilide by NE. RESULTS: IgG from NE ANCA-positive sera of patients with CIMDL inhibited the enzymatic activity of NE and did not interfere with the activity of SLPI. In contrast to the findings in WG sera, measurement of PR3 ANCA in CIMDL sera showed only fair to moderate concordance between the 2 different capture ELISAs. Cross-inhibition experiments demonstrated that NE ANCA and PR3 ANCA represent distinct autoantibodies in patients with CIMDL. CONCLUSION: The functional effects of NE ANCA on the enzymatic activity of NE or on the activity of SLPI cannot be implicated in the pathogenesis of CIMDL. The autoimmune reaction that targets neutrophil serine proteases in patients with CIMDL is frequently directed against more than one antigen. The ANCA response, including the reactivity of PR3 ANCA, in patients with CIMDL differs from what has been described in patients with WG.  相似文献   
97.
98.
In this article we analyze some of the structural characteristics of the coding section and the intron of the human chemokine CXC receptor 4 (a 7-transmembrane receptor) pre-mRNA. In the coding sequence the frequencies of the individual nucleotides do not depart significantly from 0.25, while in the intron the frequencies of the As and Gs are significantly lower and higher, respectively, than expected from a random distribution. Analysis of the pattern of association of nucleotides into triplets or couples shows that some triplets or couples occur with frequencies significantly higher or lower than expected when assuming a random association of nucleotides. In particular, in the intron combinations of the same nucleotide are over-represented. 7-or-more nucleotide repeats occur in both the coding section and the intron with frequencies which exceed the confidence limits for a random distribution. For the coding sequence this is possibly explained by the alternans of relatively similar hydrophobic-coding sections and relatively similar intervening intracellular and extracellular hydrophilic-coding sections. 7-or-more nucleotide repeats in reverse order and in reverse/complemented order occur in the intron, but not in the coding section, with frequencies which significantly exceed a random distribution. The numerous intronic repeats in reverse/complemented order may be of relevance for the secondary structure of the intron and might be one important element of the integrated splicing code.  相似文献   
99.
European Child & Adolescent Psychiatry - Attention-Deficit/Hyperactivity Disorder (ADHD) comprises disturbances in attention, emotional regulation, and reward-related processes. In spite of the...  相似文献   
100.
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