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1.
PurposeTo examine the longitudinal associations of subjectively-measured physical activity (PA) and screen time with multiple domains of cognitive development in a sample of young children.MethodsParticipants were 96 children (baseline age: 3.69 ± 0.78 years) and their parents from Edmonton, Canada in the Physical Activity and Cognition in Early Childhood (PACE) study. Different types of PA (organized, non-organized) and screen time (television viewing, video games) were measured using a parental questionnaire at baseline and at 6- and 12-month follow-ups. Total proxy-reported PA, total screen time, and meeting/not meeting the screen time recommendations (2–4 years: ≤1 h/d; 5 years: ≤2 h/d) of the Canadian 24-Hour Movement Guidelines were also calculated. Working memory (Nebraska Barnyard task) and inhibitory control (Fish-Shark Go/No-Go task) were assessed at the three time points. Intellectual ability, including language development, inductive reasoning, and perceptual speed, were assessed using the Woodcock-Johnson III test battery at 6- and 12-month follow-ups. Multilevel growth modeling was conducted.ResultsOrganized PA (B = 1.26; 95%CI: 0.19,2.33), non-organized PA (B = 0.89, 95%CI: 0.08, 1.71), and total proxy-reported PA (B = 1.03, 95%CI: 0.41,1.66) were positively associated with intellectual ability. In particular, positive associations in regard to language development and inductive reasoning were observed. As for screen time, most associations were not significant, except for positive associations of meeting the screen recommendation with intellectual ability (B = 3.19; 95%CI: 0.002,6.38) and language development (B = 4.32; 95%CI: 0.34,8.30).ConclusionFor young children, promoting PA participation in organized and non-organized activities, as well as meeting the screen time recommendations, appears important for cognitive development. 相似文献
2.
《Cirugía espa?ola》2022,100(12):762-767
IntroductionEsophageal reconstruction is a very complex surgical procedure, burdened by significant morbidity. Gastroplasty and coloplasty have classically been used. Free jejunal plasty has shown to be a very good option in the treatment of cervical esophagus pathology, but the role of supercharged jejunoplasty in thoracic esophagus reconstruction is still controversial.MethodsA retrospective study of esophageal reconstructions with jejunoplasties performed in our unit between January 2011 and December 2019. Epidemiological data, indications, surgical technique, and morbidity and mortality were analyzed.Results67 procedures of esophageal reconstruction were performed, 10 of which were jejunoplasties: 5 free jejunums and 5 supercharged. Morbidity, mortality, mean stay and withdrawal time from enteral feeding were lower in free than in supercharged jejunums.ConclusionsSupercharged jejunoplasty was the last option for reconstruction of the thoracic esophagus. Median sternotomy access provides an excellent approach to the anterior mediastinum and the internal mammary vessels. The free jejunum would be the first choice, with the indemnity of the rest of the esophagus, in the reconstruction of the cervical esophagus. 相似文献
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4.
目的:优化白及多糖的超声提取工艺,比较不同产地白及多糖含量差异,考察白及多糖稳定性和抗氧化活性。方法:以多糖得率为考察指标,料液比、超声温度、超声时间为考察因素设计L9(34)正交试验优化白及多糖超声波提取工艺;以苯酚-硫酸法测定白及多糖含量,考察陕西汉中、云南普洱、湖南洪江及四川绵阳白及多糖含量产地差异;以化学方法考察白及多糖稳定性,并比较白及多糖对1,1-二苯基-2-苦肼基自由基(DPPH·)和羟基自由基(·OH)的清除率以评价其体外抗氧化活性。结果:最佳超声提取工艺条件为:料液比1:25(g/mL)、超声温度80 ℃、超声时间10 min;四川绵阳白及多糖含量最高,达到60.81%,湖南洪江次之,云南普洱最低;白及多糖在柠檬酸及中性溶液中的稳定性较好,在苯甲酸钠、过酸性或过碱性溶液中的稳定性较差;白及多糖能有效地清除DPPH和羟基自由基,具有潜在的体外抗氧化活性。结论:白及多糖超声波提取工艺的优化及其抗氧化活性研究,可为白及多糖提取及综合利用提供借鉴。 相似文献
5.
目的阐明双氢青蒿素(DHA)诱导肿瘤细胞铁死亡的作用及其机制。方法利用3,3′,5,5′-四甲基联苯胺(TMB)检测DHA与FeSO_4体外芬顿样(Fenton)反应生成氧自由基(·OH)的能力;MTT法检测DHA对人肝癌HepG2细胞的毒性(包括FeSO_4与去铁胺预处理组)。MTT法考察谷胱甘肽(GSH)与铁死亡抑制剂(Fer-1)对DHA细胞毒性的影响;采用DCFH-DA染料考察DHA(包括FeSO_4预处理组)诱导的细胞内活性氧的生成能力;采用C11-BODIPY581/591与DiO分别考察DHA(包括FeSO_4预处理组)对细胞内脂质过氧化物生成能力以及细胞膜结构的影响;利用谷胱甘肽过氧化物酶4(GPX-4)试剂盒测定DHA(包括FeSO_4预处理组)对HepG2细胞内GPX-4活性的影响。结果 Fe~(2+)能够催化DHA发生芬顿样反应并生成·OH;DHA的半数抑制浓度(IC_(50))为(39.96±8.78)μmol/L,FeSO_4与去铁胺分别能够增加或者降低DHA的细胞毒性;DHA处理后细胞内活性氧含量与脂质过氧化物含量升高,细胞形态变大,细胞膜呈散点状分布并呈现解离状态。FeSO_4预处理组与DHA组相比较进一步增加细胞内活性氧含量与脂质过氧化物含量,并且细胞膜形态完全破坏。FeSO_4能够增强DHA对GPX-4活性的抑制作用。结论 DHA通过芬顿样反应升高细胞内活性氧而最终诱导肿瘤细胞铁死亡。另外,外源性铁可以加速DHA发生芬顿样反应进而加速肿瘤细胞铁死亡的发生与发展。 相似文献
6.
目的:研究大鼠血清氧化调节因子的增龄性改变及平补阴阳中药淫羊藿女贞子的影响作用。方法:8个月龄雄性SD大鼠,随机分为7组,饲养至相应月龄,包括9个月龄组、12个月龄组、15个月龄组、17个月龄组,淫羊藿组、女贞子组、淫羊藿女贞子组(配伍组),以3、6个月龄雄性大鼠为青年对照组。各用药组饲养至15个月龄后开始灌胃给予相应药物2个月。取血清检测以下指标:总抗氧化能力(TT-AOC)、超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-PX)、还原型谷胱甘肽(GSH)、一氧化氮(NO)、总一氧化氮合成酶(tNOS)、诱导型一氧化氮合成酶(iNOS)、结构型一氧化氮合酶(cNOS)及8-羟基脱氧鸟苷(8-OHDG)。结果:与青年大鼠比较,17个月龄大鼠血清SOD、GSH、GSH-PX及T-AOC水平显著降低(均P<0.01),NO、tNOS、iNOS、MDA及8-OHDG含量显著升高(P<0.05或0.01),cNOS差异无统计学意义。与17个月龄大鼠比较,配伍组SOD、GSH、GSH-PX及T-AOC水平显著升高(均P<0.01),NO、tNOS、iNOS、cNOS、MDA及8-OHDG含量均显著降低(P<0.05或0.01)。基于多层感知(Multi-Layer Perceptron,MLP)神经网络模型,结果显示淫羊藿女贞子合用可使17个月龄自然衰老大鼠的上述指标的改变逆转至(10.45±0.87)个月,作用优于淫羊藿、女贞子单用。结论:淫羊藿女贞子配伍延缓衰老的作用与其改善衰老大鼠血清自由基损伤有关。 相似文献
7.
《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2022,16(3):102444
Background and aimsThe negative impact of obesity on the brain is an issue of increasing clinical interest. Hence, this review summarized evidence linking obesity with brain morphology (gray and white matter volume), brain function (functional activation and connectivity), and cognitive function.MethodsA criticals review of the relevant published English articles between 2008 and 2022, using PubMed, Google Scholar and Science Direct. Studies were included if (1) an experimental/intervention study was conducted (2) the experiment/intervention included both high fat diet or body weight, whether it could counteract the negative effect brain morphological or functional change. Critical analysis for a supporting study was also carried out.ResultsBrain dysfunction can be recognized as result from neuroinflammation, oxidative stress, change in gut-brain hormonal functionality decrease regional blood flow or diminished hippocampal size and change in gut-brain hormonal functionality; which collectively translate into a cycle of deranged metabolic control and cognitive deficits, often obesity referred as changes in brain biochemistry and brain function. Recently, a few changes in brain structure and functions could be traced back even to obese children or adult. Evidence here suggested that obesity elicits early neuroinflammation effects, which likely disrupt the normal metabolism in hypothalamus, and hippocampus result from brain insulin resistance. The mechanisms of these robust effects are discussed herein.ConclusionBrain disease is inseparable from obesity itself and requires a better recognition to allow future therapeutic targeting for treatment of obesity. Additional research is needed to identify the best treatment targets and to identify if these changes reversible. 相似文献
8.
Stephen J. Winters 《Current medical research and opinion》2016,32(2):271-272
Dose adjustment with transdermal testosterone preparations should recognize the variability of serum total testosterone levels between applications and over the course of 24?h. Dose adjustments are also made difficult by between-laboratory assay variability. Low SHBG with obesity and diabetes lowers the total testosterone level, and free or bioavailable testosterone may prove to be a better choice for monitoring the progress and dosing of testosterone-treated men with adult onset hypogonadism. 相似文献
9.
《中国整形与重建外科(英文)》2020,2(2):103-106
BackgroundThrough precise understanding of the vascular anatomy of the breast, the lower segment of the breast could be harvested as a pedicled or free flap for contralateral breast reconstruction.Case presentationIn case 1, based on the 4th internal thoracic artery perforator, the pedicled flap from the breast was transferred to the contralateral side for immediate breast reconstruction. In case 2, with the thoracoacromial vascular pedicle, the free flap from the healthy breast was harvested for delayed breast reconstruction on the contralateral side.ResultsBoth flaps survived well postoperatively. A certain degree of asymmetry was observed in both cases, but the patients were satisfied with the overall results. At the end of follow-up, no tumor recurred in either breast.ConclusionIn patients with a large healthy breast, the lower segment could be harvested as a pedicled or free flap for contralateral breast reconstruction. 相似文献
10.
《Pharmacological reports : PR》2019,71(4):551-555
BackgroundIn the past two decades, enhanced understanding of the biology of G-protein-coupled receptors (GPRs) has led to the identification of several such receptors as novel targets for free fatty acids (FFAs). Two GPRs, FFAR1 and FFAR4, have received special attention in the context of chronic inflammatory diseases, thanks to their anti-inflammatory activities.MethodsThe present study investigates the influence of prolonged treatment with GW9508 – agonist of FFAR1 and FFAR4 – on the development of atherosclerosis plaque in apoE-knockout mice, using morphometric and molecular methods.ResultsGW9508 administration has led to the reduction of atheroscletoric plaque size in an apoE-knockout mice model. Moreover, a FFAR1/FFAR4 agonist reduced the content of macrophages by almost 20%, attributed by immunohistochemical phenotyping to the pro-inflammatory M1-like activation state macrophages.ConclusionsProlonged administration of GW9508 resulted in significant amelioration of atherogenesis, providing evidence that the strategy based on macrophage phenotype switching toward an M2-like activation state via stimulation of FFAR1/FFAR4 receptors holds promise for a new approach to the prevention or treatment of atherosclerosis. 相似文献