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81.
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The present study aimed to determine the effect of the functional monomer, 10‐methacryloxydecyl dihydrogen phosphate (MDP), on the enamel bond durability of single‐step self‐etch adhesives through integrating fatigue testing and long‐term water storage. An MDP‐containing self‐etch adhesive, Clearfil Bond SE ONE (SE), and an experimental adhesive, MDP‐free (MF), which comprised the same ingredients as SE apart from MDP, were used. Shear bond strength (SBS) and shear fatigue strength (SFS) were measured with or without phosphoric acid pre‐etching. The specimens were stored in distilled water for 24 h, 6 months, or 1 yr. Although similar SBS and SFS values were obtained for SE with pre‐etching and for MF after 24 h of storage in distilled water, SE with pre‐etching showed higher SBS and SFS values than MF after storage in water for 6 months or 1 yr. Regardless of the pre‐etching procedure, SE showed higher SBS and SFS values after 6 months of storage in distilled water than after 24 h or 1 yr. To conclude, MDP might play an important role in enhancing not only bond strength but also bond durability with respect to repeated subcritical loading after long‐term water storage.  相似文献   
83.
To evaluate the incremental diagnostic and prognostic value of cardiac magnetic resonance (CMR) in patients with chest pain, raised troponin and unobstructed coronary arteries, and to compare subsequent event rates between diagnostic groups. 130 patients (mean age: 54?±?17) presenting with troponin-positive acute chest pain and unobstructed coronary arteries were included. All patients were managed according to European Society of Cardiology guidelines, including echocardiography, and had CMR within 6.2?±?5.3?days of presentation. During follow-up, major adverse cardiovascular events (MACE) were recorded. CMR provided a diagnosis in 100 of 130 patients (76.9%), with the remaining 30 (23.1%) having a normal examination. CMR diagnosed 37 (28.5%) acute myocardial infarctions, 34 (26.1%) myocarditis, 28 (21.5%) apical ballooning syndromes and 1 (0.8%) hypertrophic cardiomyopathy. When a single diagnosis was suspected by the referring physician, CMR validated this diagnosis in 32 patients (76.2%). CMR provided a formal diagnosis in 61 patients (69.3%) in which the clinical diagnosis was uncertain between at least two possibilities. CMR corrected a wrong diagnosis in 10 patients (7.7%). CMR-suggested diagnosis led to a modification of therapy in 42 patients (32.3%). Median follow-up was 34?months (interquartile range 24–49) in 124 patients. Sixteen patients (12.9%) experienced MACE. MACE rate was not different between patients with a conclusive CMR and normal CMR. In patients with acute troponin-positive chest pain and unobstructed coronary arteries, early CMR has important diagnostic and therapeutic implications. However its association with occurrence of MACE during mid term follow-up was not obvious.  相似文献   
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Astrocytes are fundamental building blocks of the central nervous system. Their dysfunction has been implicated in many psychiatric disorders, including alcohol use disorder, yet our understanding of their functional role in ethanol intoxication and consumption is very limited. Astrocytes regulate behavior through multiple intracellular signaling pathways, including G-protein coupled-receptor (GPCR)-mediated calcium signals. To test the hypothesis that GPCR-induced calcium signaling is also involved in the behavioral effects of ethanol, we expressed astrocyte-specific excitatory DREADDs in the prefrontal cortex (PFC) of mice. Activating Gq-GPCR signaling in PFC astrocytes increased drinking in ethanol-naïve mice, but not in mice with a history of ethanol drinking. In contrast, reducing calcium signaling with an astrocyte-specific calcium extruder reduced ethanol intake. Cortical astrocyte calcium signaling also altered the acute stimulatory and sedative-hypnotic effects of ethanol. Astrocyte-specific Gq-DREADD activation increased both the locomotor-activating effects of low dose ethanol and the sedative-hypnotic effects of a high dose, while reduced astrocyte calcium signaling diminished sensitivity to the hypnotic effects. In addition, we found that adenosine A1 receptors were required for astrocyte calcium activation to increase ethanol sedation. These results support integral roles for PFC astrocytes in the behavioral actions of ethanol that are due, at least in part, to adenosine receptor activation.Subject terms: Astrocyte, Addiction  相似文献   
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This study's purpose was to determine whether portal hypertension adversely affects small intestinal mucosal injury. Portal hypertension was produced in male Sprague-Dawley rats by two-stage ligation of the portal vein. Sham-operated rats were used as controls. Two weeks later, intestinal injury was produced byin vivo perfusion with 5 mM chenodeoxycholic acid for 30 min. Intestinal injury was assessed by quantitative morphometry and by measuring intestinal water and mannitol absorption. Portal hypertension resulted in more injury in the distal perfused intestine as manifested by increased villus tip denudation [portal hypertensive 52.5±9.6sem) vs controls 28.1±5.7m, P=0.05). Additionally there was a significant decrease in the unperfused duodenal villus height in portal hypertensive rats (portal hypertensive 755±22 vs controls 848±28m, P<0.02). Portal hypertension had no significant effect on the increase in mannitol absorption or water secretion caused by chenodeoxycholic acid perfusion. This study suggests that portal hypertension alters small intestinal mucosa and increases susceptibility to injury.This work was supported in part by a grant from the Research Service of the Veterans Administration.  相似文献   
89.
A 50-year-old male cigarette smoker with a posterior parenchymal lung mass developed a bloody, exudative pleural effusion. Pathologic examination of the resected lung confirmed the preoperative diagnosis of an intralobar pulmonary sequestration.  相似文献   
90.
This article offers a commentary by representatives of the Association of Psychology Postdoctoral and Internship Centers (APPIC) on the 2015 article written by Gonsalvez et al. related to the assessment of clinical competencies in clinical psychology practicum students. The four competency “super clusters” derived by Gonsalvez et al. result from a unique empirical hierarchical clustering approach and are sure to add important knowledge to the field. This commentary generalizes from clinical psychology education and training in Australia to the United States, expands from practica to internship and postdoctoral training, and reflects on some relevant APPIC issues and initiatives. Future research is also suggested.  相似文献   
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