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111.
Aims   The primary aim was to compare the efficacy of smoking cessation treatment using a combination of active nicotine patch plus active nicotine gum versus therapy consisting of active nicotine patch plus placebo gum in a sample of alcohol-dependent tobacco smokers in an early phase of out-patient alcohol treatment. A secondary aim was to determine whether or not there were any carry-over effects of combination nicotine replacement on drinking outcomes.
Design   Small-scale randomized double-blind placebo-controlled clinical trial with 1-year smoking and drinking outcome assessment.
Setting   Two out-patient substance abuse clinics provided a treatment platform of behavioral alcohol and smoking treatment delivered in 3 months of weekly sessions followed by three monthly booster sessions.
Participants   Participants were 96 men and women with a diagnosis of alcohol abuse or dependence and smoking 15 or more cigarettes per day.
Intervention   All participants received open-label transdermal nicotine patches and were randomized to receive either 2 mg nicotine gum or placebo gum under double-blind conditions.
Findings   Analysis of 1-year follow-up data revealed that patients receiving nicotine patch plus active gum had better smoking outcomes than those receiving patch plus placebo gum on measures of time to smoking relapse and prolonged abstinence at 12 months. Alcohol outcomes were not significantly different across medication conditions.
Conclusions   Results of this study were consistent with results of larger trials of smokers without alcohol problems, showing that combination therapy (nicotine patch plus gum) is more effective than monotherapy (nicotine patch) for smoking cessation.  相似文献   
112.
Acanthamoeba species and leptomyxid organisms are free-living amebas that cause meningoencephalitis, primarily in immunocompromised patients. We report the isolation and culture of Acanthamoeba species and leptomyxid amebas from four patients with fatal amebic meningoencephalitis. Acanthamoeba species were cultured from brain abscess specimens from three immunocompromised patients (including two patients with AIDS). In the case of the fourth patient, who had no identifiable immunodeficiency, leptomyxid amebas were cultured from a specimen from a subcutaneous nodule and were identified in amebic granulomas in brain tissue by the indirect immunofluorescence test. Persons with advanced infection due to the human immunodeficiency virus may be at increased risk for amebic meningoencephalitis, but the diagnosis should be considered in the differential diagnosis of any immunocompromised patient with cerebral abscesses.  相似文献   
113.
OBJECTIVES: We evaluated whether statins have anti-arrhythmic effects by exploring the association of statin use with appropriate implantable cardioverter-defibrillator (ICD) therapy for ventricular tachycardia/ventricular fibrillation (VT/VF) in the Multicenter Automatic Defibrillator Implantation Trial (MADIT)-II. BACKGROUND: A few studies have suggested that lipid-lowering drugs may have anti-arrhythmic effects in patients with coronary artery disease. METHODS: Patients receiving an ICD (n = 654; U.S. centers only) in the MADIT-II study were categorized by the percentage of days each patient received statins during follow-up (90% to 100%, n = 386; 11% to 89%, n = 116; and 0% to 10%, n = 152). The Kaplan-Meier method with significance testing by the log-rank statistic and time-dependent proportional hazards regression analysis were used to evaluate the effect of statin use on the probability of ICD therapy for the combined end point VT/VF or cardiac death and for the end point VT/VF. RESULTS: The cumulative rate of ICD therapy for VT/VF or cardiac death, whichever occurred first, was significantly reduced in those with > or =90% statin usage compared to those with lower statin usage (p = 0.01). The time-dependent statin:no statin therapy hazard ratio was 0.65 (p < 0.01) for the end point of VT/VF or cardiac death and 0.72 (p = 0.046) for VT/VF after adjusting for relevant covariates. CONCLUSIONS: Statin use in patients with an ICD was associated with a reduction in the risk of cardiac death or VT/VF, whichever occurred first, and was associated with a reduction in VT/VF episodes. These findings suggest that statins have anti-arrhythmic properties.  相似文献   
114.
Multiple studies comparing sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES) in patients with coronary artery disease have been performed. Despite these comparisons, it remains uncertain whether a differential in long-term efficacy and safety exists. Unselected patients treated exclusively with 1 drug-eluting stent type were enrolled in the Registry Experience at the Washington Hospital Center with Drug-Eluting Stents. There were 2,099 patients (3,766 lesions) treated with SES and 1,079 patients (1,850 lesions) treated with PES. Patients were followed at 30 days, 1 year, and 2 years for the clinical endpoints of death, myocardial infarction, target vessel revascularization, and definite and definite/probable stent thrombosis. Patients in the SES group had more dyslipidemia, history of congestive heart failure, and ostial lesions; patients treated with PES had more previous coronary artery bypass surgery, unstable angina, and type C lesions. At 2 years, unadjusted major adverse cardiac events (MACE) (22.6% vs 21.1%, p = 0.3) and target vessel revascularization (13.3% vs 11.2%, p = 0.1) were comparable. The incidence of definite stent thrombosis was higher in the SES group (1.8% vs 0.9%, p = 0.05) driven by early events. Similar results were seen after adjustment for baseline differences: MACE (hazard ratio 1.1, 95% confidence interval [CI] 0.9 to 1.3, p = 0.5), definite stent thrombosis (hazard ratio 2.3, 95% CI 1.0 to 5.2, p = 0.05), and target vessel revascularization (hazard ratio 1.1, 95% CI 0.9 to 1.4, p = 0.4). The incidence and rate of late stent thrombosis (>30 days) were similar (0.7% vs 0.5%, p = 0.4 and 0.24%/year, both groups, respectively). In conclusion, no major differential in long-term safety or efficacy was detected between SES and PES; both stent types were efficacious in reducing revascularization but were limited by a small continual increase in late stent thrombosis.  相似文献   
115.
Western blot analysis of antibody to varicella-zoster virus   总被引:3,自引:0,他引:3  
We used western blot (WB) to compare the IgG response to varicella-zoster virus (VZV) after chickenpox (CP), zoster, and administration of a live attenuated varicella vaccine (LAVV). After CP, 13 of 14 normal children had antibody to glycoprotein (gp) I (99 and 92 kilodaltons [kDa]), 11 had antibody to gpII (133 kDa), and 10 had antibody to gpIII (119 kDa). Bands at 150 and 35 kDa were also seen in 13 and 11 sera, respectively. Bands to gpI, gpII, and p35 were more intense after zoster than CP. After one dose of LAVV, eight of eight normal children had gpI antibody. In leukemic children, gpI antibody appeared in 18 (56%) after one dose and in 25 (89%) after two doses. Upon household exposure, leukemic vaccinees who developed CP were less likely than those protected to have prior gpIII and p35 antibodies. As seen after zoster, WBs after breakthrough CP showed intense responses to VZV antigens. Thus, WB helps distinguish secondary from primary antibody responses to VZV.  相似文献   
116.
For patients undergoing elective percutaneous coronary intervention (PCI), procedural anticoagulation with bivalirudin was previously shown to significantly reduce bleeding complications at the cost of a modest increase in ischemic events compared with unfractionated heparin (UFH) and glycoprotein IIb/IIIa inhibitors (GPIs). However, the excess bleeding in patients treated with UFH and GPIs may have been caused by excessively high UFH doses and increased activated clotting times. This study sought to determine the bleeding risk of targeted low-dose UFH with GPIs compared with bivalirudin in patients undergoing elective PCI. Of 1,205 patients undergoing elective PCI, 602 underwent PCI with adjunctive UFH and GPIs with the UFH dose targeted to an activated clotting time of approximately 250 seconds, and 603 patients matched for baseline characteristics underwent PCI with bivalirudin. Outcomes were analyzed for major bleeding (hematocrit decrease >15%, gastrointestinal bleed, or major hematoma) and 6-month major adverse cardiac events (death, myocardial infarction, and target-lesion revascularization). The maximum activated clotting time achieved was 261.7 +/- 61.6 seconds in the UFH/GPI group and 355.4 +/- 66.6 in the bivalirudin group (p <0.001). In-hospital major bleeding rates were similar between groups (1.8% UFH/GPI vs 1.7% bivalirudin; p = 0.83), as were transfusion requirements (1.2% UFH/GPI vs 0.5% bivalirudin; p = 0.61). The 6-month major adverse cardiac event rate was also similar between groups (9.5% UFH/GPI vs 9.0% bivalirudin; p = 0.81). In conclusion, there were no significant differences in major bleeding and 6-month major adverse cardiac events for patients undergoing elective PCI treated with targeted low-dose UFH and GPIs compared with those treated with bivalirudin.  相似文献   
117.
Alcohol septal ablation (ASA) of patients with hypertrophic cardiomyopathy (HC) allows study of the electrocardiographic effects of myocardial necrosis confined to the base of the interventricular septum, a rare event in atherothrombotic coronary artery disease. Eighty-four consecutive patients were studied after ASA for HC. After excluding 20 with pacing before ASA and 6 with no available preprocedure electrocardiograms, the electrocardiograms of the remaining 58 patients were compared with those of 58 consecutive patients with anterior ST elevation myocardial infarctions who underwent primary intervention for left anterior descending coronary artery (LAD) occlusions. In 25 patients, the occlusions were proximal to the first septal perforator, and in 33 patients, the occlusions were more distal. All electrocardiograms were analyzed with respect to conduction abnormalities and ST-segment changes. Patients with HC developed right bundle branch block significantly more often than those with LAD occlusions (50% vs 14%, p = 0.001) Moreover, patients with HC required postprocedure pacing more frequently (14% vs 2%, p <0.05). A distinctive pattern of ST displacement was found. There was more frequent ST depression in leads I and aVF and greater ST elevation in lead V(1) in patients who underwent ASA, indicating a greater tendency toward a rightward direction than was true in patients with LAD occlusions. In conclusion, in addition to more frequent right bundle branch block after ASA, a distinctive a characteristic pattern of ST-segment deviation similar to but distinct from that produced by proximal LAD occlusion appeared.  相似文献   
118.
OBJECTIVES: This study was designed to evaluate whether the destruction of the World Trade Center (WTC) on September 11, 2001 (9/11), led to an increased frequency of ventricular arrhythmias among patients fitted with an implantable cardioverter-defibrillator (ICD). BACKGROUND: The WTC attack induced psychological distress. Because ICDs store all serious arrhythmias for months, the attack provided a unique opportunity to compare pre- and post-9/11 frequencies of potentially lethal arrhythmias among ICD patients. METHODS: Two hundred consecutive ICD patients who presented for regularly scheduled follow-up to six affiliated clinics were recruited into this observational study. The electrograms stored in the ICDs for the three months before 9/11 and 13 months thereafter were scrutinized in a blinded manner (relative to date) for all ventricular tachyarrhythmias (tachycardia or fibrillation) triggering ICD therapy. RESULTS: The frequency of tachyarrhythmias increased significantly for the 30 days post-9/11 (p = 0.004) relative to all other months between May 2001 and October 2002. In the 30 days post-9/11, 16 patients (8%) demonstrated tachyarrhythmias, compared with only seven (3.5%) in the preceding 30 days, representing a 2.3-fold increase in risk (95% confidence interval 1.1 to 4.9; p = 0.03). The first arrhythmic event did not occur for three days following 9/11, with events accumulating in a progressive non-clustered pattern. CONCLUSIONS: Ventricular arrhythmias increased by more than twofold among ICD patients following the WTC attack. The delay in onset and the non-clustered pattern of these events differ sharply from effects following other disasters, suggesting that subacute stress may have served to promote this arrhythmogenesis.  相似文献   
119.
We have evaluated the fibrinogen/fibrin fragment E antigen assay as a diagnostic test in patients with clinically suspected venous thrombosis by comparing the results of this assay with venography in 272 patients. The result of the fragment E antigen assay was elevated in 79 of 80 patients with positive venograms for recent venous thrombosis (sensitivity 99%) and within the normal range in 161 of 192 patients with normal venograms (specificity 84%). The fragment E assay was also evaluated in 130 medical and surgical controls without evidence of venous thrombosis by leg scanning and the test was found to be relatively nonspecific. However, in the patient group under study, a correct clinical diagnosis of no thrombosis, based on a normal fragment E result, was made in 161 of 162 cases (negative predictive value of 99%). Therefore, a normal test result effectively excludes a diagnosis of venous thrombosis in clinically symptomatic patients. The assay, as currently performed, is technically demanding and takes 24 hr to complete. Therefore, it will have to be simplified before it can be applied to clinical practice.  相似文献   
120.
Human low density lipoprotein (LDL) covalently conjugated with 200-250 residues of lactose per LDL particle (Lac-LDL) was bound and rapidly taken up by the galactose-specific receptor of rat hepatocytes. Uptake of Lac-LDL was associated with inhibition of 3-hydroxy-3-methylglutaryl-CoA reductase and stimulation of cholesterol esterification. Uptake of native human LDL had no significant effects on these enzyme activities even when the rates of LDL uptake equaled those of Lac-LDL. When injected into rats, Lac-LDL was selectively removed by the liver (98% of injected dose). The hepatic subcellular distribution of simultaneously injected native 125I-labeled LDL and 131I-labeled Lac-LDL differed significantly, Lac-LDL was associated with fractions enriched in lysosomal hydrolases whereas native LDL was found predominantly in the supernatant fraction enriched in lactate dehydrogenase. Chloroquine (0.1 mM) markedly suppressed uptake of Lac-LDL by cultured rat hepatocytes (> 80%) but had only a small effect on uptake of native LDL. Leupeptin (0.625 mM) inhibited degradation of Lac-LDL more than it did degradation of native LDL. Colchicine (0.25 microM) dramatically suppressed uptake of Lac-LDL (> 70%) but did not affect native LDL uptake even at concentrations as high as 10 microM. Uptake of human LDL by rat hepatocytes occurs largely by nonspecific mechanisms, including fluid endocytosis, whereas Lac-LDL, as shown here, is taken up by a specific receptor-mediated mechanism. The results show further that native human LDL, representing an example of a protein taken up nonspecifically, is processed intracellularly by a pathway qualitatively distinct from that for Lac-LDL, an example of a protein taken up by a specific mechanism. Lac-LDL may serve as a vehicle for specifically delivering drugs, hormones, or radioactive compounds to hepatocytes for therapeutic or diagnostic purposes.  相似文献   
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