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The effect of nonsteroidal antiinflammatory drugs (NSAIDs) on the risk of cardiovascular events remains controversial. Among NSAIDs, only low-dose aspirin exerts protective vascular effects. Low-dose aspirin has been proven effective for secondary prevention. For primary prevention, the usefulness of low-dose aspirin is debated, as illustrated by the differences in recommendations across countries. NSAIDs other than aspirin, whether COX-2 selective or nonselective, increase the risk of cardiovascular events. Among them, naproxen is associated with the smallest risk increase. In patients with a history of coronary artery disease, diclofenac seems to carry the greatest risk, but all NSAIDs should be avoided. Uncertainties persist about aspirin interactions with other NSAIDs and with proton pump inhibitors. An adverse effect of acetaminophen on the risk of cardiovascular disease cannot be completely ruled out.  相似文献   
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Kasaj A, Meister J, Lehmann K, Stratul SI, Schlee M, Stein JM, Willershausen B, Schmidt M. The influence of enamel matrix derivative on the angiogenic activity of primary endothelial cells. J Periodont Res 2012; 47: 479–487. © 2011 John Wiley & Sons A/S Background and Objective: Angiogenesis plays a crucial role in early wound healing and tissue regeneration. Although enamel matrix derivative (EMD) has demonstrated the potential to stimulate periodontal regeneration, the biological effects of EMD on angiogenesis and underlying mechanisms have not been fully elucidated. The aim of the present study was to examine the angiogenic effects of EMD in vitro. Material and Methods: Human umbilical vein endothelial cells (HUVECs) were used to assess the effect of EMD on proliferation, survival, adhesion and migration. The effect of EMD on HUVEC angiogenesis was assessed by a three‐dimensional sprouting assay. In order to understand the signalling mechanism of altered cell proliferation of HUVECs caused by EMD, the phosphorylation status of ERK1/2 and of the serine/threonine protein kinase Akt was analysed by western blot using phospho‐specific antibodies. Results: The proliferation of HUVECs was stimulated by 50 μg/mL EMD, whereas higher concentrations (≥ 100 μg/mL) resulted in an increased apoptotic rate. The mitogenic response to EMD was associated with the activation of ERK1/2. Enamel matrix derivative did not affect cell adhesion, but all concentrations of EMD tested (0.1–250 μg/mL) promoted migration of HUVECs. Furthermore, EMD induced capillary‐like sprout formation from HUVEC spheroids in a dose‐dependent manner. Conclusion: Our data indicate that EMD acts as a proangiogenic factor in vitro and, as such, might contribute to periodontal tissue regeneration by stimulation of vessel formation during wound healing.  相似文献   
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Performance in a semantic task is speeded up for repeated stimuli compared to novel stimuli. This conceptual priming effect is related to a decrease in functional activation within the left inferior prefrontal cortex for repeated stimulus exposure (repetition suppression). However, in contrast to perceptual priming which is known to be very robust over long periods of time, previous studies on semantic priming focused on short-term effects. The present study combined a behavioral and functional imaging experiment to investigate long-term conceptual repetition priming (retention interval 3 days). We found a highly significant decrease of reaction time for word stimuli which were presented repeatedly after 3 days both compared to initial presentation and to a matched word list. The functional magnetic resonance imaging data showed a repetition suppression within the left inferior (BA45, BA47) and middle (BA9) frontal gyrus for the comparison of known with unknown words. These data demonstrate that even over a period as long as 3 days, a repetition suppression within the left frontal network involved in semantic decision can be found. Thus, priming-related mechanisms in the semantic network may be robust over several days.  相似文献   
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Here, we analyze the complete coding sequences of all recognized tick-borne flavivirus species, including Gadgets Gully, Royal Farm and Karshi virus, seabird-associated flaviviruses, Kadam virus and previously uncharacterized isolates of Kyasanur Forest disease virus and Omsk hemorrhagic fever virus. Significant taxonomic improvements are proposed, e.g. the identification of three major groups (mammalian, seabird and Kadam tick-borne flavivirus groups), the creation of a new species (Karshi virus) and the assignment of Tick-borne encephalitis and Louping ill viruses to a unique species (Tick-borne encephalitis virus) including four viral types (i.e. Western Tick-borne encephalitis virus, Eastern Tick-borne encephalitis virus, Turkish sheep Tick-borne encephalitis virus and Louping ill Tick-borne encephalitis virus). The analyses also suggest a complex relationship between viruses infecting birds and those infecting mammals. Ticks that feed on both categories of vertebrates may constitute the evolutionary bridge between the three distinct identified lineages.  相似文献   
109.
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by progressive death of cortical and spinal motor neurons, for which there is no effective treatment. Using a cell-based assay for compounds capable of preventing motor neuron cell death in vitro, a collection of approximately 40,000 low-molecular-weight compounds was screened to identify potential small-molecule therapeutics. We report the identification of cholest-4-en-3-one, oxime (TRO19622) as a potential drug candidate for the treatment of ALS. In vitro, TRO19622 promoted motor neuron survival in the absence of trophic support in a dose-dependent manner. In vivo, TRO19622 rescued motor neurons from axotomy-induced cell death in neonatal rats and promoted nerve regeneration following sciatic nerve crush in mice. In SOD1(G93A) transgenic mice, a model of familial ALS, TRO19622 treatment improved motor performance, delayed the onset of the clinical disease, and extended survival. TRO19622 bound directly to two components of the mitochondrial permeability transition pore: the voltage-dependent anion channel and the translocator protein 18 kDa (or peripheral benzodiazepine receptor), suggesting a potential mechanism for its neuroprotective activity. TRO19622 may have therapeutic potential for ALS and other motor neuron and neurodegenerative diseases.  相似文献   
110.
OBJECTIVE: To determine whether breath sound distribution maps can differentiate between patients with pneumonia or pleural effusion versus healthy controls. METHODS: We recorded breath sounds from 20 patients conventionally diagnosed as having pleural effusion, 20 patients conventionally diagnosed as having pneumonia, and 60 healthy controls, of whom 20 served as a learning sample. All subjects were examined with a computer-based multi-sensor breath sound mapping device that records, analyzes, and displays a dynamic map of breath sound distribution. The physicians who interpreted the breath sound images were first trained in identifying common characteristics of the images from the learning sample of normals. Then the images from the 40 patients and the 40 controls were interpreted as either normal or abnormal. RESULTS: In the normal images, the left and right lung images developed synchronously and had similar size, shape, and intensity. The sensitivity and specificity of blinded differentiation between normal and abnormal images when the physician interpreter did not know the patient's workup were 82.5% and 80%, respectively. The sensitivity and specificity of blinded detection of normal and abnormal images when the interpreter did know the patient' workup were 90% and 88%, respectively. CONCLUSIONS: Computerized dynamic imaging of breath sounds is a sensitive and specific tool for distinguishing pneumonia or pleural effusion from normal lungs. The role of computerized breath sound analysis for diagnosis and monitoring of lung diseases needs further evaluation.  相似文献   
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