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21.
The objective of this study was to determine the effects of orally administered misoprostol and diclofenac on inflammation caused by particulates in the rat subcutaneous air-pouch model. Subcutaneous air pouches were formed in male Sprague-Dawley rats. The animals were premedicated by gavage with either saline, diclofenac, misoprostol, or both diclofenac and misoprostol. The air pouches were injected with either polymethyl methacrylate particles or monosodium urate crystals, and the pouch fluids were obtained at 1, 6, 24, 48, and 72 h. Leukocyte influx, tumor necrosis factor, neutral metalloprotease activity, and prostaglandin E(2) levels were measured. It was determined that leukocyte influx was inhibited by diclofenac in the acute inflammation caused by monosodium urate crystals only. In all animals receiving diclofenac, prostaglandin E(2) (PGE(2)) levels were reduced, whereas tumor necrosis factor levels were elevated. The elevation of tumor necrosis factor was prevented by the addition of misoprostol. It is concluded that the oral administration of diclofenac or misoprostol can affect levels of specific mediators involved in particulate-induced inflammation in the subcutaneous air pouch.  相似文献   
22.
Q Ye  J-H Shieh  G Morrone  M A S Moore 《Leukemia》2004,18(4):777-787
The Notch family of transmembrane receptors has been implicated in the regulation of many developmental processes. In this study, we evaluated the role of Notch4 in immature hematopoietic progenitors by inducing, with retroviral transduction, enforced expression of Int-3, the oncogenic and constitutively active form of mouse Notch4. Int-3-transduced human myeloid leukemia (HL-60) cells demonstrated significantly delayed expression of differentiation markers following retinoic acid and 12-0-tetradecanoylphorbol 13-acetate treatment. Furthermore, HL-60 cells expressing Int-3 displayed a slower growth rate than cells infected with void virus, and accumulation in the G0/G1 phases of cell cycle. Transduction with deletion mutants of Int-3 defined the importance of individual domains of the protein (in particular, the ANK domain and the C-terminal domain) in the inhibition of differentiation and growth arrest of HL-60 cells. When mouse bone marrow enriched for stem cells (5-fluorouracil-resistant, lineage negative) was transduced and cultured for two weeks, the Int-3-transduced population displayed a lower expression of differentiation markers and a three- to five-fold higher frequency of colony-forming cells (CFU-GM/BFU-E) than control cultures. These results strongly support the notion that Notch signaling inhibits differentiation and promotes expansion of hematopoietic stem/progenitor cells.  相似文献   
23.
OBJECTIVE: To describe the development and validation of the Barriers to Care Questionnaire (BCQ). METHODS: The 39-item BCQ was developed through review of the literature, focus groups, and cognitive interviews of Spanish- and English-speaking parents of children with chronic health conditions. Barriers to care are conceptualized as a multidimensional construct consisting of pragmatics, health knowledge and beliefs, expectations about care, skills, and marginalization. The BCQ was field tested in 3 samples of children with special health care needs (CSHCN). RESULTS: Response rate for the field test was 77.2%. There were minimal missing data (0.08%), no floor effects, and minimal ceiling effects (3.8%, total scale). Internal consistency reliability (alpha) for the BCQ total scale was.95 and subscale alpha ranged from.75 to.91. The BCQ total scale and subscales correlated in the expected direction with validated measures of primary care characteristics and health-related quality of life. BCQ scores were higher (fewer barriers) for children with a primary care physician and for those who reported no problems getting care or foregone care. CONCLUSION: The BCQ is a feasible, reliable, and valid instrument for measuring barriers to care for CSHCN. Its use may inform efforts to support consumer choice, enhance provider accountability, and spur quality improvement.  相似文献   
24.
Taurine is an abundant amino acid found in mammalian tissues and it has been suggested to have cyto-protective functions. The aim of the present study was to determine if taurine had the potential to reduce oxidative stress associated with metal-stimulated catecholamine oxidation. Taurine and structural analogs of taurine were tested for their ability to inhibit metal-stimulated quinone formation from dopamine or L-dopa. Oxidative damage to proteins and lipids were also assessedin vitro and the effects of taurine were determined. Taurine (20 mM) was found to decrease significantly ferric iron (50–500 μM)- and manganese (10 μM)-stimulated L-dopa or dopamine oxidation. Taurine had no effect on zinc-induced dopamine oxidation and slightly potentiated copper- and NaIO4-stimulated quinone formation. Ferric iron-stimulated lipid peroxidation was not affected by taurine (1–20 mM). Protein carbonyl formation induced by ferric iron (500 μM) and L-dopa (500 μM) was significantly reduced by 10 mM taurine. The cytotoxicity of L-dopa (250 μM) and ferric chloride (75 μM) to LLC-PK1 cells was attenuated by 10 mM taurine or hypotaurine. Homotaurine alone stimulated L-dopa oxidation and potentiated the cytotoxic effects of ferric iron. Homotaurine was found to be cytotoxic when combined with L-dopa or L-dopa/iron. In contrast, hypotaurine inhibited quinone formation and protected LLC-PK1 cells. These studies suggest that taurine may exhibit cytoprotective effects against the oxidation products of catecholamines by acting as a scavenger for free radicals and cytotoxic quinones.  相似文献   
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26.
Nanoporous Au has been subjected to serial block face-scanning electron microscopy (SBF-SEM) 3D-characterisation. Corresponding sections have been digitalized and used to evaluate the associated mechanical properties. Our investigation demonstrates that the sample is homogeneous and isotropic. The effective Young’s modulus estimated by an analytical multiscale approach agrees remarkably well with the values stated in the literature.  相似文献   
27.
目的:比较4种不同树脂粘结材料在不同深度根管内粘固纤维桩的推出强度。方法:28个单根管离体前牙截冠后行根管充填和桩道预备,随机分为4组,分别用不同的粘结材料(Ⅰ:XP Bond-Dual Cure Calibra resincement;Ⅱ:XP Bond-Dual Cure Fluorocore2;Ⅲ:Excite DSC MultiCore Flow;Ⅳ:Multilink Primer A/B MultilinkAutomix)粘固纤维桩。粘固了纤维桩的牙根切割为1mm厚的试件并将其按照根管的深度分为上部、中部和下部3组,测试其推出强度。结果:Ⅰ组、Ⅱ组上部的推出强度均显著高于下部(P<0.05),Ⅲ组、Ⅳ组的推出强度在不同深度根管间无显著性差异(P>0.05)。结论:材料的类型和根管的深度对纤维桩的固位有影响。  相似文献   
28.
Current evidence on the effects of continuous positive airway pressure (CPAP) on cardiac mechanics in patients with obstructive sleep apnea (OSA) is based on a few single studies. The authors investigated this topic through a meta‐analysis of speckle tracking echocardiography (STE) studies that provided data on left ventricular (LV) and right ventricular (RV) mechanics as assessed by global longitudinal strain (GLS). The PubMed, OVID‐MEDLINE, and Cochrane library databases were systematically analyzed to search English‐language review papers published from inception to January 31, 2022. Studies were identified by crossing the following terms: “obstructive sleep apnea”, “sleep quality”, “sleep disordered breathing”, “continuous positive airway pressure therapy”, “noninvasive ventilation”, “left ventricular hypertrophy”, “systolic dysfunction”, “global longitudinal strain”, “left ventricular mechanics”, “right ventricular mechanics”, “echocardiography” and “STE echocardiography”. The meta‐analysis, including a total of 337 patients with OSA from nine studies (follow‐up 2–24 months) showed a significant GLS improvement in both LV and RV after CPAP, standard mean difference (SMD) being 0.51±0.08, CI:0.36–0.66, p = .0001 and 0.28±0.07, CI:0.15–0.42, p = .0001), respectively. Corresponding SMD values for LV ejection fraction (LVEF) and tricuspid annular plane systolic excursion (TAPSE) were 0.20±0.06, CI:0.08–0.33, p = .001 and 0.08±0.06, CI: ‐0.04/0.20, p = .21. Our meta‐analysis suggests that: I) CPAP treatment exerts beneficial effects on biventricular function in patients with OSA; II) the assessment of cardiac mechanics by STE should be routinely recommended for monitoring cardiac function in this setting, due to limitations of conventional echocardiography in evaluating biventricular performance.  相似文献   
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30.
AIM: It has been established that antiphospholipid antibodies (aPL) are associated with recurrent abortions, but the pathophysiologic mechanisms that characterize thrombosis and recurrent pregnancy losses are still not clear.However, it is known that they are associated with the presence of antibodies directed against anionic phospholipids and putative cofactors. In this study the pathogenetic role of annexin A5, a potent anticoagulant cofactor protein for its anticoagulant property in recurrent abortions, was investigated. METHODS: Endothelial cells of human umbilical veins 'EAHY2936 Line' in culture were used, incubated with antiphospholipid anticardiolipin (ACA) antibodies purified from plasma of patients with recurrent abortions. The expression of annexin A5 on the cells with ACA was investigated by immunofluorescence and by confocal microscope. The negative control was also carried out: EAHY cells in cultivation medium without ACA. RESULTS: Confocal analysis revealed a uniform distribution of annexin A5 on the cellular membranes in the negative control. Instead, in EAHY cells with ACA, the annexin A5 appears distributed in irregular manners on the cellular membranes (cytoplasmic and nuclear). CONCLUSION: The results of an irregular 'cluster' distribution of annexin A5 on the EAHY cells in presence of aPL, and in agreement with the literature, demonstrated that aPL, inhibiting annexin A5 ability to protect anionic phospholipid, promote the coagulation factors to diffuse laterally against phospholipids.  相似文献   
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