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The Coronary Artery Revascularization Prophylaxis (CARP) study showed no survival benefit with preoperative coronary artery revascularization before elective vascular surgery. The generalizability of the trial results to all patients with multivessel coronary artery disease (CAD) has been questioned. The objective of this study was to determine the impact of prophylactic coronary revascularization on long-term survival in patients with multivessel CAD. Over a 4-year period, 1,048 patients underwent coronary angiography before vascular surgery during screening into the CARP trial. The cohort was composed of registry (n = 586) and randomized (n = 462) patients, and their survival was determined at 2.5 years after vascular surgery. High-risk coronary anatomy without previous bypass surgery included 2-vessel disease (n = 204 [19.5%]), 3-vessel disease (n = 130 [12.4%]), and left main coronary artery stenosis >/=50% (n = 48 [4.6%]). By log-rank test, preoperative revascularization was associated with improved survival in patients with a left main coronary artery stenoses (0.84 vs 0.52, p <0.01) but not those with either 2-vessel (0.80 vs 0.79, p = 0.83) or 3-vessel (0.79 vs 0.71, p = 0.15) disease. In conclusion, unprotected left main coronary artery disease was present in 4.6% of patients who underwent coronary angiography before vascular surgery, and this was the only subset of patients showing a benefit with preoperative coronary artery revascularization.  相似文献   
84.
NADH:quinone oxidoreductase (complex I) plays a pivotal role in cellular energy production. It employs a series of redox cofactors to couple electron transfer to the generation of a proton-motive force across the inner mitochondrial or bacterial cytoplasmic membrane. Complex I contains a noncovalently bound flavin mononucleotide at the active site for NADH oxidation and eight or nine iron-sulfur clusters to transfer electrons between the flavin and a quinone-binding site. Understanding the mechanism of complex I requires the properties of these clusters to be defined, both individually and as an ensemble. Most functional information on the clusters has been gained from EPR spectroscopy, but some clusters are not observed by EPR and attributing the observed signals to the structurally defined clusters is difficult. The current consensus picture relies on correlating the spectra from overexpressed subunits (containing one to four clusters) with those from intact complexes I. Here, we analyze spectra from the overexpressed NuoG subunit from Escherichia coli complex I and compare them with spectra from the intact enzyme. Consequently, we propose that EPR signals N4 and N5 have been misassigned: signal N4 is from NuoI (not NuoG) and signal N5 is from the conserved cysteine-ligated [4Fe-4S] cluster in NuoG (not from the cluster with a histidine ligand). The consequences of reassigning the EPR signals and their associated functional information on the free energy profile for electron transfer through complex I are discussed.  相似文献   
85.
Gerhardt SG  Tuder RM  Girgis RE  Yang SC  Conte JV  Orens JB 《Chest》2003,123(2):629-632
Pulmonary eosinophilia is an uncommon problem in lung transplant recipients. We report the unique occurrence of two cases of pulmonary eosinophilia in pulmonary allografts for sarcoidosis. Both patients rapidly acquired bronchiolitis obliterans syndrome (BOS) after resolution of pulmonary eosinophilia. It is known that peripheral eosinophilia is a marker for pulmonary allograft rejection, but its potential in the pathogenesis of BOS is unclear.  相似文献   
86.
OBJECTIVES: The purpose of this study was to determine quality of life (QOL) and exercise performance (EP) in patients with persistent atrial fibrillation (AF) converted to sinus rhythm (SR) compared with those remaining in or reverting to AF. BACKGROUND: Restoration of SR in patients with AF improving QOL and EP remains controversial. METHODS: Patients with persistent AF were randomized double-blind to amiodarone, sotalol, or placebo. Those not achieving SR at day 28 were cardioverted and classified into SR or AF groups at 8 weeks (n = 624) and 1 year (n = 556). The QOL (SF-36), symptom checklist (SCL), specific activity scale (SAS), AF severity scale (AFSS), and EP were assessed. RESULTS: Favorable changes were seen in SR patients at 8 weeks in physical functioning (p < 0.001), physical role limitations (p = 0.03), general health (p = 0.002), and vitality (p < 0.001), and at 1 year in general health (p = 0.007) and social functioning (p = 0.02). Changes in the scores for SCL severity (p = 0.01), functional capacity (p = 0.003), and AFSS symptom burden (p < 0.001) at 8 weeks and in SCL severity (p < 0.01) and AF symptom burden (p < 0.001) at 1 year showed significant improvements in SR versus AF. Symptomatic patients were more likely to have improvement. The EP in SR versus AF was greater from baseline to 8 weeks (p = 0.01) and to 1 year (p = 0.02). The EP correlated with physical functioning and functional capacity except in the AF group at 1 year. CONCLUSIONS: In patients with persistent AF, restoration and maintenance of SR was associated with improvements in QOL measures and EP. There was a strong correlation between QOL measures and EP.  相似文献   
87.
Background: Osteoporosis (OP) is a growing health problem not only in women but also in men. Subjects and methods: This study was carried out on 100 healthy men, age range 30–65 years (mean ± SD, 44.65 ± 8.3). All were randomly recruited from Assiut city during the period January 2005 to January 2006. Complete clinical history included occupational history, smoking habit, physical activity and calcium intake. Complete clinical examination and anthropometric measurments were done. Laboratory investigations for serum calcium, phosphorus and osteocalcin were performed. Bone mineral density (BMD) was measured by calcaneal ultrasound. Results: Sixty‐three percent of participants had normal BMD, 37% had low BMD, (26% had quantitative bone ultrasound [QUS] T‐score –1 to –2.5 and 11% had QUS T‐score ≤ –2.5). Smoking and low physical activity were risk factors for low BMD. Significant positive correlations were found between BMD and body mass index, serum calcium, and osteocalcin and negative correlation with phosphorus. We concluded that low BMD occurs with high frequency in Egyptian men. Smoking, physical inactivity and low body index are significant risk factors. Low serum calcium, low serum osteocalcin and high serum phosphorus are biochemical risk factors of low BMD in males.  相似文献   
88.
OBJECTIVES: Chronically ill patients who are not satisfied with their care may change healthcare providers or systems, which could disrupt continuity of care and impede management of their conditions. We examined whether patient satisfaction affected subsequent use of non-Veterans Affairs (VA) services among chronically ill veterans discharged from VA hospitals. METHODS: The data used in this study came from a multicenter trial of increased access to primary care. We enrolled patients with diabetes, heart failure, and/or chronic obstructive pulmonary disease who were discharged from 1 of 9 VA medical centers. At baseline, we assessed satisfaction using the Patient Satisfaction Questionnaire. VA and non-VA utilization over the subsequent 6 months were assessed using VA and Medicare administrative data, non-VA billing data, and patient interviews. Using multivariable logistic regression analyses, we examined whether baseline patient satisfaction was associated with non-VA inpatient or outpatient utilization during the next 6 months. We conducted the same analysis for Medicare-eligible veterans, a group with better access to non-VA care. RESULTS: Of 1375 study patients, 174 (13%) used non-VA healthcare. Patients with non-VA utilization were older and lived farther from a VA. The odds of non-VA use decreased by 11% as satisfaction increased (odds ratio 0.89; 95% confidence interval 0.83-0.97; P = 0.005). This relationship was strongest among Medicare-eligible veterans (odds ratio 0.85; 95% confidence interval 0.77-0.93; P = 0.001). CONCLUSIONS: Dissatisfied veterans discharged from the hospital were more likely to go outside VA for care. Thus, improvements in patient satisfaction may lead to improvements in continuity of care.  相似文献   
89.
Brugada syndrome is believed to be the cause of up to 50% of sudden cardiac death (SCD) cases due to ventricular dysrhythmias in young healthy individuals with no structural heart disease. This syndrome was first reported in 1992 and is rarely seen in the Emergency Department (ED). Given the life-threatening nature of Brugada syndrome, we hope to increase awareness in Emergency Medicine practitioners. We report the case of a 22-year-old man who was referred to the ED with a history of intermittent palpitations, near-syncope and electrocardiogram findings of RSR' and ST elevation in V1-V2 characteristic of Brugada syndrome. It is crucial that emergency physicians search for this diagnosis, as an implantable cardioverter-defibrillator is the only recognized life-saving intervention, and the risk of SCD is high if the diagnosis is missed.  相似文献   
90.
The Global Program for Elimination of Lymphatic Filariasis calls for mass drug administration for endemic populations outside of sub-Saharan Africa with a single dose of diethylcarbamazine (DEC) and albendazole (Alb) annually for 4-6 years. Single-dose DEC/Alb dramatically reduces blood microfilaria (MF) counts, but most treated subjects fail to completely clear MF after a single dose. A more effective regimen might reduce the number of years required for elimination programs. We performed a randomized clinical trial in Egyptian adults with asymptomatic microfilaremia to compare treatment with seven daily doses of oral DEC (6 mg/kg) and Alb (400 mg) with a single dose of the same combination. We also studied the effect of re-treatment with single-dose DEC/Alb 12 months after the first treatment course. Multi-dose DEC/Alb was significantly more effective than single-dose therapy for reducing and clearing microfilaremia (mean reduction in MF/ml relative to pretreatment counts at 12 months, 99.6% versus 85.7%, with complete clearance in 75% versus 23.1%). The two regimens had similar activity against adult filarial worms, as indicated by serial ultrasound assessments. Neither regimen resulted in complete clearance of filarial antigenemia. There was no difference in adverse events, which were mild to moderate. Blood microfilaria and parasite antigen clearance rates increased following re-treatment. Multi-dose DEC/Alb may be a useful option for filariasis elimination programs, especially in the first year (when enthusiasm for mass drug administration and coverage rates are high), to quickly reduce community MF loads and transmission rates.  相似文献   
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