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We describe the pattern of cognitive profiles within a community-based sample of patients with Parkinson's disease (PD) and dementia (PDD) using cluster analyses, and compare the results with data from patients with Alzheimer's disease (AD) and dementia with Lewy bodies (DLB). Fifty patients with PDD and 39 with AD from Stavanger, Norway, and 62 patients with DLB from San Diego, CA, USA were diagnosed by either standardized clinical procedures or criteria (all PDD and all AD cases) or necropsy (all DLB cases). Four subgroups were identified: two subgroups with a subcortical cognitive profile (one with mild and one with moderate dementia severity), one subgroup with global impairment and severe dementia, and one subgroup with a cortical cognitive profile and moderate dementia. Of the patients with PDD and with DLB, 56% and 55%, respectively, had a subcortical cognitive profile, compared with only 33% of the AD patients. Conversely, 30% of the patients with PDD and 26% of those with DLB had a cortical cognitive profile, compared with 67% of the patients with AD. These findings suggest that in some patients with PDD, frontosubcortical changes are the main contributing factor to dementia, whereas in other patients, cortical and hippocampal changes are more important.  相似文献   
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OBJECTIVES: This study was performed to evaluate the clinical and serial angiographic outcomes of patients undergoing sirolimus-eluting stent (SES) implantation for unprotected left main coronary artery (LMCA) stenosis. BACKGROUND: The efficacy of SES has led to their expanded use for off-label indications, including LMCA disease. METHODS: Unprotected LMCA intervention with SES was attempted in 50 patients. Surveillance angiography was performed at three and nine months' follow-up. RESULTS: The target lesion involved the distal LMCA in 47 patients (94%). In-lesion restenosis occurred in 21 patients (42%), was focal in 85% of cases, and in 82% involved the branch ostia, sparing the LMCA itself. Target lesion revascularization (TLR) occurred in 19 patients (38%) over a mean follow-up of 276 +/- 57 days; TLR was ischemia-driven in 7 patients (14%). Late loss was significantly greater within the left circumflex (LCX) ostium compared to the parent vessel (PV) of the LMCA bifurcation (0.83 +/- 0.89 mm vs. 0.49 +/- 0.72 mm, p = 0.04). Late loss continued to increase between three- and nine-month follow-up. Final minimal luminal diameter and maximal balloon pressure were independent predictors of restenosis of the PV. CONCLUSIONS: Restenosis is a frequent finding when serial angiographic follow-up is performed after SES implantation for unprotected distal LMCA lesions. Restenosis is usually focal, most often involves the LCX ostium, and often occurs without symptoms.  相似文献   
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We estimated the impact of a comprehensive set of non-pharmeceutical interventions on the COVID-19 epidemic growth rate across the 37 member states of the Organisation for Economic Co-operation and Development during the early phase of the COVID-19 pandemic and between October and December 2020. For this task, we conducted a data-driven, longitudinal analysis using a multilevel modelling approach with both maximum likelihood and Bayesian estimation. We found that during the early phase of the epidemic: implementing restrictions on gatherings of more than 100 people, between 11 and 100 people, and 10 people or less was associated with a respective average reduction of 2.58%, 2.78% and 2.81% in the daily growth rate in weekly confirmed cases; requiring closing for some sectors or for all but essential workplaces with an average reduction of 1.51% and 1.78%; requiring closing of some school levels or all school levels with an average reduction of 1.12% or 1.65%; recommending mask wearing with an average reduction of 0.45%, requiring mask wearing country-wide in specific public spaces or in specific geographical areas within the country with an average reduction of 0.44%, requiring mask-wearing country-wide in all public places or all public places where social distancing is not possible with an average reduction of 0.96%; and number of tests per thousand population with an average reduction of 0.02% per unit increase. Between October and December 2020 work closing requirements and testing policy were significant predictors of the epidemic growth rate. These findings provide evidence to support policy decision-making regarding which NPIs to implement to control the spread of the COVID-19 pandemic.

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Diabetes mellitus (DM) increases mortality in acute ST-segment elevation myocardial infarction (STEMI) but the responsible mechanism is not fully elucidated. We compared the rate of successful myocardial reperfusion measured by tissue myocardial perfusion grade (TMPG) and outcomes in patients with and without DM undergoing primary percutaneous coronary intervention (PCI) for STEMI. Patients enrolled in the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS AMI) trial were analyzed according to presence of DM with respect to TMPG after PCI and outcomes at 30 days and 3 years. Multivariable logistic regression was performed to identify the independent contribution to mortality of DM and TMPG and the interaction between the 2 was assessed. Complete data were available for 3,265 patients, of whom 533 (16.3%) had DM. Diabetic patients were significantly older and heavier and had more risk factors for coronary disease and more previous MI, revascularization, and heart failure. There were no differences in rates of Thrombolysis In Myocardial Infarction grade 3 flow after PCI in the infarct artery or TMPG 2/3 between patients with and without DM. Compared to nondiabetics, mortality was significantly higher at 30 days and at 3 years in the DM group (1.8% vs 4.5%, p = 0.0002 and 5.4% vs 11.0%, p <0.0001, respectively). DM and TMPG were significantly associated with 3-year mortality, but there was no statistical interaction between DM and TMPG (p = 0.70). In conclusion, DM is associated with a significantly higher risk of death but this association is not mediated by impaired epicardial or myocardial reperfusion.  相似文献   
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Background : Myocardial infarct size is a strong independent predictor of mortality in patients with ST‐elevation myocardial infarction (STEMI). In the Harmonizing Outcomes with RevasculariZatiON and Stents in Acute Myocardial Infarction (HORIZONS‐AMI) trial, bivalirudin compared with unfractionated heparin plus a glycoprotein IIb/IIIa inhibitor reduced cardiac mortality in STEMI patients, which was attributed to reduced major bleeding. Whether a possible reduction in infarct size with bivalirudin may have contributed to the enhanced survival with this agent is unknown. Methods : Cardiac magnetic resonance imaging was performed within 7 days and after 6 months in 51 randomized patients from a single center in HORIZONS‐AMI trial (N = 28 bivalirudin, N = 23 heparin plus abciximab). Infarct size, microvascular obstruction (MVO), left ventricular ejection fraction (LVEF), and LV end‐diastolic and end‐systolic volume indices were evaluated. Results : Infarct size was not significantly different after treatment with bivalirudin compared with heparin plus abciximab either within 7 days (median 9.3% [interquartile range 4.9%, 26.6%] vs. 20.0% [5.9%, 28.2%], P = 0.28) or at 6 months 6.7% [3.8%, 20.0%] vs. 8.2% [1.8%, 16.5%], P = 0.73). MVO was present in 28.6% versus 34.8% of patients respectively (P = 0.63). LVEF and LV volume indices also did not significantly differ between the two groups at either time period, nor were differences in myocardial recovery evident. Conclusions : In conclusion, in the HORIZONS‐AMI Cardiac magnetic resonance imaging (CMRI) substudy, cardiac magnetic resonance imaging within 7 days and at 6 months after primary percutaneous coronary intervention (PCI) did not demonstrate significant differences in infarct size, MVO, LVEF, or LV volume indices in patients treated with bivalirudin compared with unfractionated heparin plus abciximab. © 2011 Wiley Periodicals, Inc.  相似文献   
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One of the strategies employed to increase the sensitivity of the fluorescence-based biosensors is to deposit chromophores on plasmonic metasurfaces which are periodic arrays of resonating nano-antennas that allow the control of the electromagnetic field leading to fluorescence enhancement. While artificially engineered metasurfaces realized by micro/nano-fabrication techniques lead to a precise tailoring of the excitation field and resonant cavity properties, the technological overhead, small areas, and high manufacturing cost renders them unsuitable for mass production. A method to circumvent these challenges is to use random distribution of metallic nanoparticles sustaining plasmonic resonances, which present the properties required to significantly enhance the fluorescence. We investigate metasurfaces composed of random aggregates of metal nanoparticles deposited on a silicon and glass substrates. The finite difference time domain simulations of the interaction of the incident electromagnetic wave with the structures reveals a significant enhancement of the excitation field, which is due to the resonant plasmonic modes sustained by the nanoparticles aggregates. We experimentally investigated the role of these structures in the fluorescent behaviour of Rhodamine 6G dispersed in polymethylmethacrylate finding an enhancement that is 423-fold. This suggests that nanoparticle aggregates have the potential to constitute a suitable platform for low-cost, mass-produced fluorescent biosensors.  相似文献   
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