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Recent pharmacotherapy trials in Parkinson's disease (PD) using dopaminergic neuroimaging as outcome parameter failed to show significant relationships between imaging and clinical results. One possible explanation is that there is a non-linear relationship between striatal denervation and motor performance reflecting a statistical "floor" effect in the imaging data with advanced disease. Both the motor manifestations and the striatal dopamine denervation of idiopathic PD, however, are typically asymmetric and more meaningful associations may be found by comparing data from the least denervated striatum with motor performance in the corresponding body side. PD patients (n=28) underwent [11C]beta-CFT dopamine transporter (DAT) positron emission tomography (PET) and grooved pegboard testing. Voxel-based analysis of DAT PET and bimanual pegboard scores demonstrated significant correlation clusters within the bilateral striata (P<0.001). However, findings were most prominent in the least denervated striatum. There was a significant inverse correlation between pegboard scores of the least affected arm and DAT binding of the least denervated striatum (Rs=-0.69, P<0.0001) but no significant correlation between pegboard scores of the clinically most affected arm and DAT binding of the most denervated striatum (Rs=-0.15, ns). These data indicate that the robustness of the grooved pegboard test as a biomarker for nigrostriatal denervation in PD mainly reflects the relationship between test performance of the clinically least affected limb and the least denervated striatum. These findings indicate that there is both a statistical "floor" and "ceiling" effect for the most affected striatal and body sides that must be considered when employing imaging as an outcome measure in clinical trials in PD.  相似文献   
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Annals of Surgical Oncology - Poor prognosis in liver cancer is due to its high frequency of intrahepatic metastasis. Cancer stem-like cells (CSLCs), which possess the properties of stemness, tumor...  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - To determine the relationship between the peripapillary choroidal thickness (ppCT) and the degree and distribution of the...  相似文献   
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The COVID‐19 pandemic has rapidly evolved and changed our way of life in an unprecedented manner. The emergence of COVID‐19 has impacted transplantation worldwide. The impact has not been just restricted to issues pertaining to donors or recipients, but also health‐care resource utilization as the intensity of cases in certain jurisdictions exceeds available capacity. Here we provide a personal viewpoint representing different jurisdictions from around the world in order to outline the impact of the current COVID‐19 pandemic on organ transplantation. Based on our collective experience, we discuss mitigation strategies such as donor screening, resource planning, and a staged approach to transplant volume considerations as local resource issues demand. We also discuss issues related to transplant‐related research during the pandemic, the role of transplant infectious diseases, and the influence of transplant societies for education and disseminating current information.  相似文献   
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The purpose of this study is to compare clinical outcomes of left ventricular assist device (LVAD) patients with device thrombosis who underwent device exchange (DE) or medical therapy (MT) alone. Consecutive patients undergoing LVAD implant between July 2008 and December 2017 were included. Device thrombosis was diagnosed with comprehensive assessments including ramp test, laboratory data, device parameters, and clinical presentations. First, MT was initiated in all patients. After MT, DE was considered if device thrombosis was refractory to initial MT, and it caused end-organ impairment and/or hemodynamic instability. Among 319 consecutive LVAD patients, 43 patients (13.5%) were diagnosed with device thrombosis. DE was performed in 28 patients (DE group); device explant was performed in 1 patient. MT was continued in 14 patients (MT group). In-hospital mortality was significantly lower in the DE group than the MT group (3.6% [1/28] vs. 28.6% [4/14], = .0184). One-year survival was significantly better in the DE group (74.0% vs. 30.1%; log-rank = .001), and freedom from cerebrovascular accident (CVA) at 1 year was greater in the DE group (87.1% vs. 47.7%; log-rank = .004). DE was associated with improved 1-year survival and fewer CVAs. Surgical intervention, if feasible, is recommended for LVAD device thrombosis.  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - Recently, artificial intelligence has been used to determine sex using fundus photographs alone. We had earlier reported that sex...  相似文献   
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