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Twelve genetically determined brain polypeptide charge variants were identified by comparing cerebellar vermis of 7 inbred mouse strains and of mice selectively bred from 8 strains closely related to these 7 ancestral strains and one other for acute behavioral sensitivity to the sedative effects of ethanol. The selectively bred ethanol-sensitive (LS, long sleep) and insensitive (SS, short sleep) mice exhibited different allelic variants at 6 of these 12 gene loci expressed in the cerebellum. Variant polypeptide A1 (81 kdalton, pI 5.6) was shown to be associated with the membrane of synaptosomal mitochondria and to exhibit a basic variant in SS mice that is determined by a dominant allele. Other variant polypeptides showed codominant inheritance in F1 crosses. However, the phenotype of no single one of these brain polypeptides consistently correlated with the ethanol behavioral sensitivity of the 7 inbred mouse strains nor of 8 recombinant inbred (B X D, C57BL X DBA) strains. This finding supports the hypothesis that a substantial amount of inbreeding, leading to random fixation of alleles independent of selection for ethanol sensitivity, occurred during the breeding of the SS and LS mice. The present findings of a lack of a strong association between sleep time and a brain polypeptide variant do not preclude the existence of a major gene effect contributing to variation in acute sensitivity to ethanol but are consistent with reports that multiple loci are responsible for the difference in ethanol sensitivity between SS and LS mice.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Two odontogenic keratocysts occurring in the anterior portion of the maxilla, an unusual location, are reported. In one instance, the clinical and radiographic features simulated a nasopalatine cyst. It is suggested that a likely origin for an odontogenic keratocyst in this location is the primordium of a mesiodens that fails to develop.  相似文献   
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BACKGROUND  Normal and low ejection fraction (EF) heart failure patients appear to have similar outcomes. OBJECTIVE  The object of this study was to determine whether sex modifies the effects of left ventricular EF on prevalent heart failure mortality. DESIGN  Prospective cohort study. PATIENTS  Patients (n = 6, 095) with a diagnosis of heart failure and a measure of EF undergoing cardiac catheterization in Alberta, Canada between April 1999 and December 2004; follow-up continued through October 2005. MEASUREMENTS  All-cause mortality was assessed in analyses stratified by patient sex and EF (≤50% vs. >50%). MAIN RESULTS  Overall, female heart failure patients were older, had more hypertension, valvular disease, less systolic impairment and coronary artery disease. Baseline medication use was similar in the four sex-EF groups. Low EF heart failure mortality over 6.5 years was slightly higher but was not significantly modified by patient sex. This relationship remained unchanged after adjustment for differences in baseline characteristics and process of care (women normal EF, reference group; men normal EF adjusted HR 1.1, 95% CI 0.9–1.3; women low EF adjusted HR 1.5, 95% CI 1.1–2.0; men low EF adjusted HR 1.6, 95% CI 1.2–2.1). CONCLUSIONS  Patient sex did not appear to modify the negative effects of low EF on long-term survival in this prospective study of prevalent heart failure. The small absolute difference in survival between low and normal EF heart failure highlights the need for further research into optimal therapy for the latter, a less well-understood condition. Preliminary findings presented as a poster at the Canadian Society of Internal Medicine Annual Meeting, Calgary, Alberta on November 2, 2006  相似文献   
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Lipid-lowering therapy, particularly with statins, reduces the risk of cardiovascular mortality; however, there is uncertainty about their efficacy in patients with heart failure, including those without coronary artery stenosis. A clinical database was studied to determine whether lipid-lowering therapy is associated with improved survival in persons with heart failure-with or without concomitant coronary artery stenosis. During an 8-year period, 6060 people with a history of heart failure underwent coronary angiography. At the time of angiography, 1216 received a lipid-lowering agent. During a median follow-up of 4.7 years, 7.1 deaths per 100 person-years occurred among users of lipid-lowering therapy, compared with 7.8 per 100 person-years among nonusers (adjusted hazard ratio 0.87, 95% confidence interval 0.77-0.97). Use of lipid-lowering therapy was associated with a reduced risk of death in patients with heart failure. Current evidence supports statin use in individuals with recognized heart failure and concomitant coronary heart disease, dyslipidemia, or diabetes mellitus. More data are needed before statins can be recommended in those with isolated heart failure.  相似文献   
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This paper prospectively documents the health-related quality of life (HRQoL) and social participation benefits of adult patients receiving cochlear implants in Australia and New Zealand. Thirty-four consecutively implanted patients completed the Assessment of Quality of Life (AQoL) and Hearing Participation Scale (HPS) instruments before implantation, and at 3– and 6–month follow-ups. Implantation resulted in significant improvements in AQoL and HPS scores. The effect size was 1.09 for both measures. Those in the top socio-economic tertile obtained the greatest gains. The HRQoL and social participation benefits were slightly larger than those reported elsewhere. This may be because participants used more recent technology (Nucleus 24 rather than Nucleus 22) and received auditory and self-efficacy training as part of their rehabilitation. The results suggest that cochlear implants have a large beneficial effect. They show that social and HRQoL outcomes can be parsimoniously measured using the HPS and AQoL instruments.  相似文献   
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Background

In order to reduce the delays encountered through patient transfer, regional care models have been developed that directly transport subsets of acute myocardial infarction (AMI) patients to hospitals with percutaneous coronary intervention (PCI) facilities. Calgary is a Canadian city that implemented this type of model in 2004.

Methods

The study population included 9768 AMI patients admitted to Calgary hospitals between 1997 and 2007. Administrative data were used to define patients who were directly admitted to the PCI hospital and those transferred there after initial admission to a hospital without specialized cardiac care. The differences in clinical characteristics and mortality trends of patients grouped by hospital delivery site and transfer practice are described.

Results

The proportion of patients directly admitted to a PCI hospital has increased with the implementation of a regional care model. Among patients admitted to non-PCI facilities, the patients who are transferred are younger, more likely to be male, have a shorter length of stay, and have lower proportions of several comorbid conditions. The risk-adjusted in-hospital mortality odds ratio for patients who received care at the PCI hospital postmodel relative to those treated at non-PCI hospitals premodel was 0.38 (95% confidence interval, 0.31-0.47). The corresponding adjusted odds ratio was 0.60 (0.47-0.76).

Conclusions

Our results suggest changing care over time and trends toward improved outcomes. Patients' clinical characteristics appear to play a major role in the decision to transfer. Avoidance of the risk treatment paradox through refinement of regional transfer protocols ought to be a priority.  相似文献   
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