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A series of derivatives analogous to Nb-benzoyltryptamine were synthesized by the Schotten-Bauman procedure. The products obtained were: Nb-4-methoxy-benzoyltryptamine, Nb-2,4-dimethoxy-benzoyltryptamine, Nb-3,4-dimethoxy-benzoyltryptamine, Nb-3,4-methylenedioxy-benzoyltryptamine and Nb-3,4,5-trimethoxy-benzoyltryptamine. They were characterized through the usual spectrometric methods (UV, IR, 1H and 13C NMR) and showed non-selective relaxant activity in guinea-pig ileum pre-contracted with acetylcholine, histamine and KCl.  相似文献   
95.
In patients with acute myocardial infarction (AMI), little is known about the correlation between prognostic variables and aspects of ruptured plaque at the coronary angiography. Five hundred patients with acute myocardial infarction were studied in a consecutive and prospective manner; of these, 264 patients were excluded mainly because of the presence of an occluded culprit coronary artery. The remaining 236 patients were divided according to the presence (113, 52%) or absence (126, 48%) of angiographic aspects suggestive of ruptured plaque, and correlated with 49 clinical, electrocardiographic, in-hospital complications, procedures, and other angiographic prognostic variables. The variables that correlated significantly and independently with angiographic aspects of ruptured plaque were: presence of thrombi and higher degree of residual stenosis at the culprit coronary artery, as well as white ethnic group.  相似文献   
96.
This in vitro research verified the possibility of eliminating staining caused by coffee and red wine in five composite resins, after being submitted to thermal cycling. Thirty-six specimens were prepared and immersed in water at 37°C for 24 hours. After polishing, specimen color was measured in a spectrophotometer Cintra 10 UV (Visible Spectrometer, GBC, Braeside, VIC, Australia). All specimens were submitted to thermal cycling at temperatures of 5 and 55°C with a dwell time of 1 minute, for 1,000 cycles in a 75% ethanol/water solution. After thermal cycling, the specimens were immersed in water at 37°C until 7 days had elapsed from the time the specimens were prepared. All specimens were then taken to the spectrophotometer for color measurement. The specimens were divided into three groups (N = 12): distilled water (control), coffee, and red wine. For the staining process to occur on only one surface, all the sides, except one, of the surfaces were isolated with white wax. The specimens were immersed in one of the solutions at 37°C for 14 days. The specimens were dried and taken to the spectrophotometer for color measurement. After this, the specimens were submitted to 20 μm wear three times, and the color was measured after each one of the wear procedures. Calculation of the color difference was made using CIEDE2000 formula. According to the methodology used in this research, it was concluded that the staining caused by coffee and red wine was superficial and one wear of 20 μm was sufficient to remove the discoloration.  相似文献   
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This article reports the case of a young female adult with GAPO syndrome who presented as a peculiar dental finding unerupted primary and permanent dentitions, which resembled total anodontia on clinical examination. A cephalometric analysis was performed to investigate the alterations in facial bone development. This is the 9th GAPO syndrome case reported in a Brazilian patient.  相似文献   
99.
The purpose of this study was to evaluate the acceptability of a brief, video-based parental intervention that modeled parent-child communication about tobacco, delivered within an emergency department (ED) setting. While waiting to be seen by a physician in the ED, 20 parent-youth dyads watched the video together and then private, semi-structured focused interviews were conducted around the "take home" message and views on the settings, actors, and content of the videos. Dyads agreed that the design, delivery, and content of the video intervention were acceptable, realistic, and useful in providing parental reinforcements about the importance of parent-youth tobacco communication and the ED was considered to be a good setting for watching the video. Our findings support the development and delivery of such an ED intervention and aids in determining content and scenarios for future intervention development.  相似文献   
100.
Glial cell line-derived neurotrophic factor (GDNF) is widely recognized as a potent survival factor for dopaminergic neurons of the nigrostriatal pathway that degenerate in Parkinson's disease (PD). In animal models of PD, GDNF delivery to the striatum or the substantia nigra protects dopaminergic neurons against subsequent toxin-induced injury and rescues previously damaged neurons, promoting recovery of the motor function. Thus, GDNF was proposed as a potential therapy to PD aimed at slowing down, halting or reversing neurodegeneration, an issue addressed in previous reviews. However, the use of GDNF as a therapeutic agent for PD is hampered by the difficulty in delivering it to the brain. Another potential strategy is to stimulate the endogenous expression of GDNF, but in order to do that we need to understand how GDNF expression is regulated. The aim of this review is to do a comprehensive analysis of the state of the art on the control of endogenous GDNF expression in the nervous system, focusing mainly on the nigrostriatal pathway. We address the control of GDNF expression during development, in the adult brain and after injury, and how damaged neurons signal glial cells to up-regulate GDNF. Pharmacological agents or natural molecules that increase GDNF expression and show neuroprotective activity in animal models of PD are reviewed. We also provide an integrated overview of the signalling pathways linking receptors for these molecules to the induction of GDNF gene, which might also become targets for neuroprotective therapies in PD.  相似文献   
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