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81.
The implant surface must withstand high insertion torque during implant insertion. The aim of this study was to investigate the damage to implant surfaces caused by two different insertion protocols in vitro. Fifteen titanium implants per group were inserted in standardized polyurethane foam models, group 1 according to a non-threaded surgical protocol and group 2 according to a threaded surgical protocol. Before and after insertion, the surfaces were visualized by scanning electron microscopy (SEM) and non-contact laser profilometry. Different surface area parameters were evaluated and maximum torque during insertion was determined. SEM detected topographical changes such as deposition of the test block and smoothening of the surface in the region of the thread crests in both groups. The laser profilometry analysis revealed significant changes in the surface topography of the implants in both groups, but no differences between the groups. Insertion torque was significantly decreased in the threaded group. Both types of surgical intervention resulted in surface damage. Less damage was detected to the thread crests with the use of a thread cutter, and most of the surface was not visibly affected by the surgical protocol at the microscopic level. The surgical protocol seems to have a minor influence on preservation of the implant surface.  相似文献   
82.
目的:观察水陆地黄汤对气阴两虚夹瘀型糖尿病肾病氧化应激及临床指标的影响。方法:60例气阴两虚夹瘀型糖尿病肾病患者随机分为对照组与联合组,每组30例,对照组给予盐酸贝那普利片10 mg,1次/d,联合组在对照组基础上加服水陆地黄汤,1剂/d。治疗12周后观察两组氧化应激指标:谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)、丙二醛(MDA)及临床指标:空腹血糖(FPG)、餐后2 h血糖(2 hPG)、糖化血红蛋白(HbA1c)、尿微量白蛋白(mALB)、24 h尿蛋白定量(24 hU-PQ)、肾小球滤过率(eGFR)的变化及临床症状的改善。结果:联合组治疗总有效率为90.0%,与对照组56.7%比较,差异有统计学意义(P<0.05);治疗后联合组MDA较治疗前均降低(P<0.05),SOD、GSH-Px均高于治疗前(P<0.05),与对照组比较,差异有统计学意义(P<0.05);联合组FPG、2 hPG、HbA1c、mALB、24 hU-PQ、eGFR较治疗前均降低(P<0.01)。结论:水陆地黄汤联合盐酸贝那普利可改善气阴两虚夹瘀型糖尿病肾病氧化应激状态,明显缓解临床症状,延缓病程进展。  相似文献   
83.
Baicalein (5,6,7-trihydroxyflavone), isolated from the root of traditional Chinese herb Scutellaria baicalensis Georgi, has anti-inflammatory and anti-oxidative activities. This study explored the protective and modulatory mechanisms of baicalein on neuroinflammation, oxidative stress and metabolic abnormality in lipopolysaccharide (LPS)-activated BV-2 cells. Our results demonstrated that treatment with baicalein remarkably restrained the production of pro-inflammatory factors including nitric oxide (NO), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in LPS-activated BV-2 cells. Moreover, baicalein significantly inhibited reactive oxygen species (ROS) production, decreased cyclooxygenase-2 (COX-2) and nuclear factor-b (NF-κB)/p65 expression. 1H NMR metabolomics analysis revealed that 12 differential metabolites were regulated by baicalein, implicated in alanine, aspartate and glutamate metabolism, glutathione metabolism, arginine and proline metabolism, D-glutamine and D-glutamate metabolism. In conclusion, these results indicated that baicalein has protective and modulatory effects on neuroinflammation and oxidative stress in LPS-activated BV-2 cells.  相似文献   
84.
Environmental exposures and genome maintenance mechanisms that respond to environmentally-induced genotoxicity have a profound impact on human health. Eight review articles in this Special Issue (SI) titled “Environmental Health and Genome Integrity” describe emerging new mechanisms by which distinct forms of environmentally-induced DNA damage are remediated, and explain how DNA repair pathway choices impact genome integrity and disease propensity. Here, we provide an introduction to reviews from this SI. Our expanding knowledge of how genotoxic exposures impact the genome will allow us to better predict, prevent and treat environmentally-induced human diseases such as cancer and neurodegenerative disorders.  相似文献   
85.
目的探讨乙酰谷酰胺对酒精中毒昏迷患者的急救效果和血清β内啡肽(β-EP)、氧化应激指标的影响。方法选择2017年1月-2019年3月成都市第三人民医院蒲江医院接诊的115例酒精中毒昏迷患者,通过随机数表法分为观察组60例和对照组55例。两组入院后均给予常规治疗,对照组在此基础上给予盐酸纳洛酮注射液治疗,观察组在对照组基础上,联合乙酰谷酰胺注射液治疗。比较两组临床疗效、临床症状恢复时间、肝功能、血清β-EP、氧化应激指标和清醒后不适症状。结果观察组总有效率明显高于对照组(P<0.05);两组体温正常时间比较差异无统计学意义(P>0.05),观察组苏醒时间、生命体征稳定时间明显短于对照组(P<0.05);治疗后,观察组肝功能指标谷草转氨酶(AST)、谷丙转氨酶(ALT)、γ-谷氨酰转肽酶(γ-GT)明显低于对照组(P<0.05);观察组血清β-EP、丙二醛(MDA)明显低于对照组,超氧化物歧化酶(SOD)明显比对照组高(P<0.05);观察组头晕头痛、恶心呕吐、乏力、胸闷发生率均明显低于对照组(P<0.05)。结论在常规治疗基础上,联合乙酰谷酰胺对酒精中毒昏迷患者急救疗效显著,且可有效改善肝功能及血清β-EP、氧化应激指标的表达,减少清醒后不适症状的发生率,值得应用推广。  相似文献   
86.
Pesticide exposure is associated with cognitive and psychomotor disorders. Glyphosate-based herbicides (GlyBH) are among the most used agrochemicals, and inhalation of GlyBH sprays may arise from frequent aerial pulverizations. Previously, we described that intranasal (IN) administration of GlyBH in mice decreases locomotor activity, increases anxiety, and impairs recognition memory. Then, the aim of the present study was to investigate the mechanisms involved in GlyBH neurotoxicity after IN administration. Adult male CF-1 mice were exposed to GlyBH IN administration (equivalent to 50 mg/kg/day of Gly acid, 3 days a week, during 4 weeks). Total thiol content and the activity of the enzymes catalase, acetylcholinesterase and transaminases were evaluated in different brain areas. In addition, markers of the cholinergic and the nigrostriatal pathways, as well as of astrocytes were evaluated by fluorescence microscopy in coronal brain sections. The brain areas chosen for analysis were those seen to be affected in our previous study. GlyBH IN administration impaired the redox balance of the brain and modified the activities of enzymes involved in cholinergic and glutamatergic pathways. Moreover, GlyBH treatment decreased the number of cholinergic neurons in the medial septum as well as the expression of the α7-acetylcholine receptor in the hippocampus. Also, the number of astrocytes increased in the anterior olfactory nucleus of the exposed mice. Taken together, these disturbances may contribute to the neurobehavioural impairments reported previously by us after IN GlyBH administration in mice.  相似文献   
87.
Bisphenol A (BPA) is one of the most widely used chemicals in plastic industry, which enters the human body through occupational and food contact. We studied the protein changes in rat cerebral cortex to evaluate the neurotoxicity of BPA. Twenty-four adult male rats were randomly selected and divided into four groups and each group respectively received 0, 0.5, 5 and 50 mg/kg of BPA for 4 weeks orally. To determine the oxidative status, reduced glutathione content and the level of malondialdehyde were measured in brain cortical tissue. The proteins of each sample extracted and separated on a two-dimensional acrylamide gel electrophoresis. From the obtained protein map, the 10 most altered protein spots were used for mass spectroscopy analysis. The lipid peroxidation in both doses of 0.5 and 5 mg/kg was significantly higher than the control group, but the glutathione content had no significant difference between the groups. Based on the results of the MS data analysis by the MASCOT database search engine, 10 proteins with altered intensity were identified as pyruvate kinase, alpha-enolase, aconitate hydratase, creatine kinase B-type, phosphatidylethanolamine-binding protein 1, 14-3-3 protein eta, guanine nucleotide-binding protein subunit beta-1, dihydropyrimidinase-related protein 2, glutamine synthetase and the neurofilament light polypeptide. There are several reports suggesting that the increase or decrease in the level and activity of these 10 proteins, similar to those observed in this study, is related to some neurological and psychosocial disorders including neurodegenerative diseases, schizophrenia, depression, epilepsy and some brain tumors.  相似文献   
88.
Objective2D Ultrasound (US) imaging has been recently investigated as a more accessible alternative to 3D Magnetic Resonance Imaging (MRI) for the estimation of soft issue motion under external mechanical loading. In the context of pressure ulcer prevention, the aim of this pilot MRI study was to design an experiment to characterize the sacral soft tissue motion under a controlled mechanical loading. Such an experiment targeted the estimation of the discrepancy between tissue motion assessed using a 2D imaging modality (echography) versus tissue motion assessed using a (reference) 3D imaging modality (MRI).MethodsOne healthy male volunteer participated in the study. An MRI-compatible custom-made setup was designed and used to load the top region of the sacrum with a 3D-printed copy of the US transducer. Five MR images were collected, one in the unloaded and four in the different loaded configurations (400–1200 [g]). Then, a 3D displacement field for each loading configuration was extracted based on the results of digital volume correlation. Tissue motion was separated into the X, Y, Z directions of the MRI coordinate system and the ratios between the out-of-plane and in-plane components were assessed for each voxel of the selected region of interest.ResultsRatios between the out-of-plane and in-plane displacement components were higher than 0.6 for more than half of the voxels in the region of interest for all load cases and higher than 1 for at least quarter of the voxels when loads of 400–800 [g] were used.ConclusionThe out-of-ultrasound-plane tissue displacement was not negligible, therefore 2D US imaging should be used with caution for the evaluation of the tissue motion in the sacrum region. The 3D US modality should be further investigated for this application.  相似文献   
89.
BackgroundNon-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. Insulin resistance, oxidative stress, and obesity are major contributors to NAFLD pathogenesis. The effects of garlic powder supplementation on these risk factors in patients with NAFLD was investigated.MethodsIn this 12-wk, randomized controlled clinical trial, ninety patients with NAFLD were randomly assigned to two groups. The treatment group received four tablets of garlic (each coated tablet contained 400 mg garlic powder) daily and the control group received four tablets of placebo (each coated tablet contained 400 mg starch).ResultsA significant decrease was seen in the treatment group compared to the control group in waist circumference (P = 0.001), body fat percent (P < 0.001), serum concentration of fasting blood sugar (P = 0.01), insulin (P < 0.001), homeostatic model assessment for insulin resistance (P < 0.001), and malondialdehyde (P < 0.001), as well as significant increase in skeletal muscle mass (P = 0.002), serum concentration of superoxide dismutase (P < 0.001), and total antioxidant capacity (P < 0.001).ConclusionGarlic powder supplementation improved risk factors of NAFLD. Further studies are needed to determine the effects of garlic on hepatic features in patients with NAFLD. The study protocol was registered at Iranian clinical trials website under code IRCT20170206032417N4.  相似文献   
90.
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