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951.
The impact of bone marrow fibrosis grade on the prognosis of patients with chronic myelomonocytic leukemia (CMML) remains controversial. Therefore, we examined the records of 82 patients diagnosed with CMML at our institution and summarized baseline characteristics and molecular profiles by subgroups of absent or mild (grades 0/1) and moderate (grade 2) fibrosis. Cox proportional hazards models were constructed to assess the prognostic significance of fibrosis grade. Grade 2 fibrosis was identified in 63 patients (76.8%), grade 1 in 16 patients (19.5%), and grade 0 in 3 patients (3.7%). Grade 2 fibrosis was associated with reduced hemoglobin levels (median 9.75 vs 11.0 g/dL in grade 0/1; p?=?0.04) and increased percentages of ringed sideroblasts (7.5 vs 0%; p?=?0.008). In multivariable analysis, grade 2 fibrosis was an independent predictor of poor overall survival (OS; 95% CI 1.32–6.35; HR 2.90; p?=?0.008), but not event-free survival (EFS; 95% CI 0.62–2.67; HR 1.28; p?=?0.50). Absolute neutrophil count (ANC) was found to impact OS (95% CI 1.01–1.09; HR 1.05; p?=?0.009), while both ANC (95% CI 1.00–1.07; HR 1.04; p?=?0.04) and peripheral blood blast percentage (95% CI 1.02–1.32; HR 1.16; p?=?0.02) impacted EFS. These results implicate fibrosis grade is an important indicator of prognosis, with high-grade fibrosis predicting inferior survival. Given the prevalence of marrow fibrosis in CMML, fibrosis grading should be incorporated into prognostic assessment and therapeutic decision-making.  相似文献   
952.
The purpose of this study was to assess whether the degree of fluoroscopic aortic valve calcification could help identify the presence of aortic stenosis in the elderly. To evaluate the diagnostic utility of cardiac fluoroscopy for the detection of aortic stenosis (aortic valve area less than or equal to 1.0 cm 2) in patients 60 years or older, aortic valve area determined by cardiac catheterization was related to the pattern of calcification seen on cinefluoroscopy in 97 patients (mean age of 72 +/- 6 years) with suspected aortic stenosis. Dense circumferential (3+) calcification of the aortic valve was seen on cinefluoroscopy in 56 of 59 patients with an aortic valve area less than or equal to 1.0 cm 2 (sensitivity 95%), compared to 5 of 38 patients with aortic valve area greater than 1.0 cm2 (specificity 87%) (p less than .001). These findings suggest that in patients 60 years of age or older with suspected aortic stenosis, a dense circumferential (3+) aortic valve calcification on cinefluoroscopy is highly predictive of an aortic valve area less than or equal to 1.0 cm2 with a positive predictive accuracy of 91% and a negative predictive accuracy of 91%. Thus cinefluoroscopy may provide an accurate adjunct or alternative to Doppler echocardiography in the assessment of aortic stenosis in the elderly.  相似文献   
953.
Chemotactic and random migrations of neutrophils derived from four patients with primary hyperparathyroidism were found to be defective. These abnormalities improved significantly in parallel with the decrease in serum calcium and parathormone and with the increase in serum phosphorus concentration after surgical removal of the adenoma. These observation suggest a possible role for parathormone phosphorus and calcium in the motility of neutrophils.  相似文献   
954.
Linking is an electrophysiologic phenomenon in which each successive impulse entering a macroreentry circuit propagates preferentially along 1 limb because of the functional impedance to conduction in the contralateral limb produced by the previous impulse. Electrophysiologic studies were performed in 12 patients with a bidirectionally conducting accessory pathway. Linking was analyzed while 1:1 atrioventricular conduction took place through the normal pathway. When atrial pacing (at the same cycle length) could be initiated during sinus rhythm in patients with rapidly conducting accessory pathways, linking was dynamically maintained by repetitive local refractoriness (interference). When it could be initiated during the usual type of orthodromic circus movement tachycardia, linking was sustained by actual impulse collision, the underlying mechanism having also been called entrainment. When it could be initiated during sinus rhythm in a patient with a slowly conducting accessory pathway, linking was maintained by impulse collision, but the underlying mechanism could not be called entrainment because stimulation had not been started during tachycardia. This study showed that 2 terms--linking and entrainment--may be applied to the same mechanism and, conversely, that the same name could not be used in reference to the same mechanism when pacing was initiated under different circumstances. However, using the proposed conceptual formulation for linking, it is apparent that seemingly diverse mechanisms associated with macroreentry circuits involving accessory pathways are, in fact, variations on a common electrophysiologic theme.  相似文献   
955.
Asymptomatic ("silent") ischaemia has been shown to be of prognostic significance in patients with stable and unstable angina and more recently in patients recovering after myocardial infarction. No therapeutic regimen has yet been shown to improve the prognosis of patients with silent ischaemia after infarction, which can be found in as many as a third of these patients. Attempts to achieve therapeutic revascularisation in all these patients may be undesirable, but early revascularisation could be especially beneficial in some selected high risk patients. Two hundred and fifty consecutive clinically stable survivors of myocardial infarction who had predischarge submaximal exercise tests were followed up for a year. Silent ischaemia was found in 27% of these patients; 15% had symptomatic ischaemia. Patients with a positive exercise test were prescribed a beta blocker before discharge. Mortality in patients with silent (9.4%) and symptomatic (5.4%) ischaemia in the first year after infarction was not significantly different. Patients with symptomatic ischaemia were more likely to have undergone coronary artery bypass grafting in the first year. Patients with silent ischaemia were, however, significantly more likely to die than patients with a negative exercise test (relative odds 12:1). Patients with silent ischaemia and an abnormal blood pressure response or who could not complete a submaximal exercise protocol were at particularly high risk, being 32 times more likely to die than those with a negative test (95% confidence interval from 3.3 to 307 times more likely). First year mortality in this group was 22%. The benefits of therapeutic revascularisation in this high risk group need to be studied.  相似文献   
956.
Reperfusion therapy with thrombolytic agents has been a significant advancement in the management of patients with acute ST elevation myocardial infarction. The outcome of acute myocardial infarction has significantly improved by early application of thrombolytic therapy. Intracoronary streptokinase has been used for >30 years, but reawakening interest occurred in the early 1980s in the use of thrombolytic therapy to establish rapid reperfusion during an acute myocardial infarction. Initial studies aimed at direct intracoronary thrombolysis, but owing to its cumbersome process and requirement of an active round the clock cardiac catheterization laboratory, it has been replaced by regimens of intravenous thrombolytic therapy which is as efficacious as intracoronary administration. Consideration of thrombolytic therapy has become a standard treatment for patients presenting with acute ST elevation myocardial infarction and various well-controlled trials have demonstrated the importance of both early and full reperfusion in improving clinical outcome in the setting of acute myocardial infarction. The subject of intravenous thrombolysis is perhaps the most rapidly evolving area in the management of acute myocardial infarction patients in the past decade. The current review focuses on the thrombolysis in the treatment of myocardial infarction and other conditions.  相似文献   
957.

Objectives

The purpose of the current study was to assess the effect of angiotensin-converting enzyme inhibitor (ACEI) therapy in facilitating cardioversion from persistent atrial fibrillation (AF) and maintaining sinus rhythm.

Background

Pharmacologic therapy and electrical cardioversion for AF are often unsuccessful in maintaining long-term sinus rhythm.

Methods

The current study, a 1-year, prospective follow-up, comprised 47 patients with persistent AF undergoing electrical cardioversion. Patients receiving ACEI were compared with those receiving other medications. The study end point was the number of defibrillation attempts required for atrial defibrillation and the number of hospital admissions. A secondary end point was change in signal-averaged P-wave duration (SAPD) 1 year after successful electrical cardioversion.

Results

Of those admitted and requiring electrical defibrillation, the number of defibrillation attempts required for successful cardioversion was significantly less in the ACEI group (P < .001). The incidence rate ratio for admissions comparing recipients of ACEI with others was 0.14 (P = .03). Patients receiving ACEI therapy had significantly lower SAPD at 1 year when compared with the no-ACEI group (135 ms ± 3 vs 150 ms ± 2, P = .002).

Conclusions

The use of long-term ACEI therapy facilitated electrical defibrillation in patients with persistent AF. ACEI therapy also reduced SAPD, suggesting amelioration of the arrhythmogenic substrate. Furthermore, we confirmed that SAPD is prolonged in patients with persistent AF.  相似文献   
958.
AIMS: To compare interferon monotherapy with its combination with lamivudine for hepatitis B e antigen (HBeAg)-positive hepatitis B treatment. METHODS: Two independent researchers identified pertinent randomized controlled trials. The trials were evaluated for methodological quality and heterogeneity. Rates of sustained virological and biochemical responses, and HBeAg clearance and seroconversion were used as primary efficacy measures. Quantitative meta-analyses were conducted to assess differences between groups for conventional and pegylated interferon, and overall. RESULTS: Greater sustained virological, biochemical and seroconversion rates were observed with addition of lamivudine to conventional [odds ratio (OR)=3.1, 95% confidence intervals (CI) (1.7-5.5), P<0.0001, OR=1.8, 95% CI (1.2-2.7), P=0.007 and OR=1.8, 95% CI (1.1-2.8), P=0.01 respectively], although not pegylated [OR=1.1, 95% CI (0.5-2.3), P=0.8, OR=1.0, 95% CI (0.7-1.3), P=0.94, and OR=0.9, 95% CI (0.6-1.2), P=0.34 respectively] interferon-alpha, with no significant affect on HBeAg clearance rates [OR=1.6, 95% CI (0.9-2.7), P=0.09, and OR=0.8, 95% CI (0.6-1.1), P=0.26 respectively]. Excluding virological response (P<0.001), pegylated interferon monotherapy and conventional interferon and lamivudine combination therapy were similarly efficacious (P>0.05), with the former studied in harder to treat patients, as evidenced by the superior virological response observed with conventional as compared with pegylated interferon monotherapy (P<0.0001). CONCLUSION: In comparable populations, pegylated interferon monotherapy is likely to be equally or more efficacious than conventional interferon and lamivudine combination therapy, thus constituting the treatment of choice, with no added benefit with lamivudine addition. However, when conventional interferon is used, its combination with lamivudine should be considered.  相似文献   
959.
Thoracic outlet syndrome (TOS) associated with congenital clavicular pseudoarthrosis is rare in adults and often misdiagnosed. In this case report, we describe an adult female who was found to have thromoosis of the subclavian and axillary arteries with embolization documented by invasive angiography. This unusual vascular manifestation of TOS should remind physicians that anatomic derangements may predispose to upper extremity ischemia. © 1995 Wiley-Liss, Inc.  相似文献   
960.
Prospective data of 3,120 consecutive patients who had elective coronary artery bypass were analyzed to identify patient profile, cost, outcome and predictors of those readmitted to the intensive care unit. Group A (n=3,002) had a single intensive care unit admission and group B (n=118) were readmitted within 30 days after surgery. Parsonnet score, EuroSCORE, age, body mass index, chronic obstructive airway disease, peripheral vascular disease, renal dysfunction, unstable angina, congestive cardiac failure, and poor left ventricular function were higher in group B. Bypass and crossclamp times were longer, and the prevalence of inotropic and balloon pump support, arrhythmias, myocardial infarction, re-exploration, blood loss and transfusion, cerebrovascular accident, wound infection, sternal dehiscence, and multisystem failure were higher in group B. Despite a 4-fold increase in cost of care, the mortality rate (32.4%) of patients readmitted to intensive care was 23-times higher than routine patients (1.4%). Crossclamp time>80 min, Parsonnet score>10, EuroSCORE>9, sternal dehiscence, ventricular arrhythmias, and renal failure predicted readmission.  相似文献   
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