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71.
Introduction: Routine thrombectomy has been advocated for ST-segment-elevation myocardial infarction (STEMI), but it is unknown how many patients present with a large thrombus. We aimed to quantify the intracoronary thrombus in STEMI and to correlate it with procedure results.
Methods: In 98 patients with STEMI and TIMI flow grades 0–2 in the infarct-related artery, thrombus was qualified as small (ST) when its maximal dimension was <2 vessel diameters and large (LT) when ≥2. Main outcome measures were TIMI flow, myocardial blush grade (MBG), corrected TIMI frame count (cTFC), and ST-segment elevation resolution (STSER).
Results: Only a third of the patients presented with an LT. Thrombus grade was independent of the initial vessel patency. Diabetes (OR 3.1, 95% CI 1.20–8.02, P = 0.027) and pretreatment with clopidogrel (OR 0.27, 95% CI 0.08–0.86, P = 0.034) were independent predictors of LT. LT was an independent predictor of unfavorable results: <3 TIMI flow (OR 2.87, 95% CI 1.04–8.00, P = 0.043), MBG 0–1 (OR 3.36, 95% CI 1.10–10.26, P = 0.033), cTFC > 21 (OR 2.86, 95% CI 1.09–7.49, P = 0.033) and <50% STSER (OR 3.19, 95% CI 1.06–9.63, P = 0.039).
Conclusion: Only a third of STEMI patients present with an LT, being diabetes and lack of clopidogrel pretreatment independent predictors. An LT is strongly associated with worse PCI results.  相似文献   
72.
To determine whether patients with a HLA-identical sibling donor have a better outcome than patients without a donor, an analysis on the basis of intention-to-treat principles was performed within the framework of the EORTC-GIMEMA randomized phase III AML 8A trial. Patients in complete remission (CR) received one intensive consolidation course. Patients with a histocompatible sibling donor were then allocated allogeneic bone marrow transplantation (alloBMT), the patients without a donor were randomized between autologous BMT (ABMT) and a second intensive consolidation (IC2). 831 patients <46 years old and alive >8 weeks from diagnosis were included. HLA typing was performed in 672 patients. AlloBMT was performed during CR1 in 180 (61%) out of 295 patients with a donor. Another 38 patients were allografted: five in resistant disease, 14 during relapse and 19 in CR2. ABMT was performed in 130 (34%) out of 377 patients without a donor in CR1, in six (2%) patients during relapse and in 38 (10%) patients during CR2. The disease-free survival (DFS) from CR for patients with a donor was significantly longer than for patients without a donor (46% v 33% at 6 years; P = 0.01, RR 0.78, 95% confidence interval 0.63–0.96). The overall survival from diagnosis for patients with a donor was longer, but not statistically significant, than for patients without a donor (48% v 40% at 6 years; logrank P = 0.24). When patients were stratified according to prognostic risk groups, the same trend in favour of patients with a donor was seen for survival duration and the DFS remained significantly longer for this group of patients.  相似文献   
73.
Bioavailability of Soil-Bound TCDD: Oral Bioavailability in the Rat   总被引:1,自引:1,他引:0  
Bioavailability of Soil-Bound TCDD: Oral Bioavailability inthe Rat. SHU, H., PAUSTENBACH, D., MURRAY, F. J., MARPLE, L.,BRUNCK, B., DEI ROSSI, D., TEITELBAUM, P. (1988). Fundam ApplToxicol. 10, 648–654. The implications to the public healthof trace amounts of 2,3,7,8-TCDD in the environment are underevaluation by regulatory agencies in the United States and WesternEurope. One major consideration in such evaluations is the contributionto human exposure via ingestion of TCDD-contaminated soil. An80% figure is under consideration by some regulators for estimatedhuman exposure. A contractor for one agency has, in fact, useda value of 1007% bioavailability for estimating human bioavailability.Several studies have investigated the oral bioavailability ofTCDD from contaminated soil in animals. Most have reported estimatesof 25–50%, although one has reported <0.5 and 85%,depending on the source of the contaminated soil. This paperreports an oral bioavailability of approximately 43% in therat dosed with three environmentally contaminated soil samplesfrom Times Beach, Missouri. This figure did not change significantlyover a 500-fold dose range of 2 to 1450 ng TCDD/kg of body weightfor soil contaminated with approximately 2, 30, or 600 ppb ofTCDD. The relevance of animal oral bioavailability data forthe human remains to be evaluated. However, since regulatoryagencies use animal data for extrapolating to humans, the 43%or 25–50% figure would be more accurate than the 80 or100% estimates.  相似文献   
74.
This study measures the resistance to gas flow of different double-lumen bronchial tubes used for separate ventilation of each lung in critically ill patients. Different-sized Robertshaw and Carlens' tubes were studied, as well as a new device that consisted of a cuffed bronchial catheter introduced through a standard tracheal tube. The pressure-flow relationship was curvilinear in all cases. Robertshaw and Carlens' tubes were generally found to have bronchial and tracheal channels with almost similar resistance and offered total resistances similar to those of 7.0-8.0 mm internal diameter tracheal tubes. The new device had a higher resistance than others of equal external diameter. This must be taken into account when its use is recommended for prolonged respiratory support.  相似文献   
75.
An infant with congenital junctional ectopic tachyardia required frequent hospitalizations due to tachycardia acceleration despite multiple antiarrhythmic medications. At 9 months of age, he underwent successful radiofrequency catheter ablation of the tachycardia with preservation of AV conduction.  相似文献   
76.
A high incidence of α1-antitrypsin (AAT) deficiency has been reported in patients with C-ANCA systemic vasculitis in association with antibodies against proteinase-3 (PR3). To clarify the role of AAT deficiency in the acute vasculitic process as well as in progression of the disease, we studied 84 patients with either C-ANCA or P-ANCA vasculitis with special reference to: (a) the AAT gene, (b) the phenotypic (Pi) variants and (c) the serum levels during both acute illness and remission. The PiZ gene was found in six patients (8% vs. 1.5% controls) irrespective of the type of autoantibodies (C-ANCA vs. P-ANCA). All PiZ patients displayed the ability to raise their AAT serum levels up to the normal range during acute illness. In contrast, 24 patients with the PiM phenotype presented low AAT serum levels during acute illness. In all these patients, the AAT levels returned to normal values during the remission. Low AAT levels were associated with low levels of C-reactive protein (PCR) ( P  < 0.001), with a less severe renal involvement or a minor risk of death, and, in one tested patient, with a novel point mutation (TCGA → TCAA) at the enhancer–promoter region of the AAT gene. Low AAT serum levels did not correlate with either type/titre of autoantibody or distribution/severity of the vasculitis process. In the case–control study, high AAT levels emerged as a major determinant of progression towards end-stage renal failure [odds ratio 3 (95% CI 1.1–8.4)]. These results indicate: (a) a high incidence of the PiZ gene of AAT in systemic vasculitis irrespective of the type of autoantibodies; (b) a novel form of AAT deficiency associated with the normal PiM phenotype becoming manifest only during acute illness; (c) dysregulation of the acute-phase response affecting selectively AAT or both AAT and PCR; (d) correlation between low plasma levels of AAT and less severe renal involvement or risk of death.  相似文献   
77.
78.
Summary Protein A-sepharose affinity chromatography was used to isolate IgG subclasses from the serum of CBA mice chronically infected with Schistosoma mansoni. The subclasses were tested for the presence of two antibodies which are responsible for the death of young schistosomula in vitro; 'lethal antibody' (LA), which kills schistosomula in co-operation with complement and 'eosinophil adherence antibody' (EAA) which causes the death of schistosomula by promoting the adherence of eosinophils to the parasite. LA and EAA were detected only in the IgG fraction of the serum. LA was concentrated in the IgG2a fraction and EAA in the IgG1 fraction. The development of IgG subclasses specific for schistosomula was followed in mice exposed to twenty cercariae by the fluorescent antibody technique. IgG1, IgG2a and IgG2b antibodies were detected 2 weeks after infection and their titres rose steadily to reach high levels by weeks 12 or 14. IgM antibody was not detected until week 6 and IgA until week 10; both were present at lower concentrations than the IgG1 antibodies.  相似文献   
79.
In a group of 70 patients, 29 women and 41 men, with atypicalchest pain and normal findings at coronary arteriography, somehemodynamic and angiographic parameters of left ventricularfunction were measured, for the purpose of determining the valuesof normality and to document possible differences between sexes. Of the diastolic parameters, the left ventricular end-diastolicpressure and volume was lower in women than in men, the LVEDPbeing 11.9 ± 3.4 against 13.7 ± 3.6 mm Hg (P <0.025), and ED V of 76.1 ± 15 against 89.5 ± 23ml/m2 (P < 0.005). Of the systolic parameters, the ejection fraction of 74 ±7% in women was significantly higher than that of 67 ±7% in men (P < 0.0005), and so was the mean velocity of volumereduction of 2.59 ± 0.58 of women against that of 2.26± 0.35 of men (P < 0.01). The physiological diversity between the sexes, with women showinga constant hyperdynamic condition in comparison to men, withsmaller ventricular volumes and increased contraction, seemsto offer a possible explanation for some intriguing aspectsof the diagnosis of ischemic heart disease in the female sex.  相似文献   
80.
Background: Although it has been recently demonstrated that there was no significant difference in total survival and clinical outcomes between patients who underwent coronary artery bypass grafting (CABG) with or without surgical ventricular reconstruction (SVR), the question of whether or not SVR decreases the arrhythmic risk profile in this population has not been clarified yet. Objective: To determine the real incidence of sudden cardiac death (SCD) and sustained ventricular tachycardia/ventricular fibrillation (sustained VT/VF) in patients following CABG added to SVR and to define their clinical and echocardiographic parameters predicting in‐hospital and long‐term arrhythmic events (SCD + sustained VT/VF). Methods: Pre‐ and postoperative clinical and echocardiographic values as well as postoperative electrocardiogram Holter data of 65 patients (21 female, 63 ± 11 years) who underwent SVR + CABG were retrospectively evaluated. Results: Mean follow‐up was 1,105 ± 940 days. At 3 years, the SCD‐free rate was 98% and the rate free from arrhythmic events was 88%. Multivariate logistic analysis identified a preoperative left ventricular end‐systolic volume index (LVESVI) > 102 mL/m2 (odds ratio [OR] 1.4, confidence interval [CI] 1.073–1.864, P = 0.02; sensitivity 100%, specificity 94%) and a postoperative pulmonary artery systolic pressure (PASP) > 27 mmHg (OR 2.3, CI 1.887–4.487, P = 0.01; sensitivity 100%, specificity 71%) as independent predictors of arrhythmic events. Conclusions: Our and previous studies report a low incidence of arrhythmic events in patients following SVR added to CABG, considering the high‐risk profile of the study population. A preoperative LVESVI > 102 mL/m2 and a postoperative PASP > 27 mmHg had a good sensitivity and specificity in predicting arrhythmic events. (PACE 2010; 33:1054–1062)  相似文献   
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