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91.
目的研究45 d-6°头低位卧床对尿液中Ca和P元素昼夜节律的影响,探讨卧床实验中骨丢失的可能规律与机制。方法收集卧床实验8名受试者尿样,每个时间段连续收集3 d。采用电感耦合等离子体发射光谱仪(ICP-OES)对尿样中的Ca,P和K三种元素的含量进行检测,并对Ca和P等元素的昼夜节律特征进行分析。结果尿Ca总含量在卧床前、中、后3个时间段无显著差异,但Ca元素的日间含量在卧床中的早期和晚期阶段都显著降低,在卧床后又恢复至接近卧床前水平。尿中P元素总含量在卧床中的早期显著升高,随后不断下降,到卧床晚期则显著低于卧床前水平,P元素在日间和夜间的变化趋势差异不大。反映骨质变化的Ca/P参数在卧床中和卧床后也有显著变化。此外,卧床实验也对尿液中Ca和P含量变化的昼夜节律具有影响。结论卧床实验对于尿中Ca和P含量及Ca/P参数产生显著影响,同时也影响了Ca和P含量的节律性,这些变化可能与卧床过程中骨代谢失衡有关。 相似文献
92.
Muslum Kul Fatih Unal Hasan Kandemir Bahram Sarkarati Kamer Kilinc Sultan Basmac? Kandemir 《Psychiatry investigation》2015,12(3):361-366
Objective
Oxidative metabolism is impaired in several medical conditions including psychiatric disorders, and this imbalance may be involved in the etiology of these diseases. The present study evaluated oxidative balance in pediatric and adolescent patients with attention deficit hyperactivity disorder (ADHD).Methods
The study included 48 children and adolescents (34 male, 14 female) with ADHD who had no neurological, systemic, or comorbid psychiatric disorders, with the exception of oppositional defiant disorder (ODD), and 24 sex- and age-matched healthy controls (17 male and seven female).Results
TAS was significantly lower, and TOS and OSI were significantly higher in patients with ADHD than in healthy controls. Total antioxidant levels were lower in patients with comorbid ODD than in those with no comorbidity. No difference was found in TOS or OSI among the ADHD subtypes; however, TAS was higher in the attention-deficient subtype.Conclusion
Our findings demonstrated that oxidative balance is impaired and oxidative stress is increased in children and adolescents with ADHD. This results are consistent with those of previous studies. 相似文献93.
《Nutrition, metabolism, and cardiovascular diseases : NMCD》2020,30(12):2351-2362
Background and aimsTriglyceride glucose (TyG) index is considered a new surrogate marker of insulin resistance that associated with the development of vascular disease. The aim of this study was to evaluate the prognostic value of TyG index in patients with acute myocardial infarction (AMI).Methods and resultsA total of 3181 patients with AMI were included in the analysis. Patients were stratified into 2 groups according to their TyG index levels: the TyG index <8.88 group and the TyG index ≥8.88 group. The incidence of major adverse cardiovascular events (MACEs) during a median of 33.3-month follow-up were recorded. Multivariable Cox regression models revealed that the TyG index was positively associated with all-cause death [HR (95% CI): 1.51 (1.10,2.06), p = 0.010], cardiac death [HR (95% CI): 1.68 (1.19,2.38), p = 0.004], revascularization [HR (95% CI): 1.50 (1.16,1.94), p = 0.002], cardiac rehospitalization [HR (95% CI): 1.25 (1.05,1.49), p = 0.012], and composite MACEs [HR (95% CI): 1.19 (1.01,1.41), p = 0.046] in patients with AMI. The independent predictive effect of TyG index on composite MACEs was mainly reflected in the subgroups of male gender and smoker. The area under the curve (AUC) of the TyG index predicting the occurrence of MACEs in AMI patients was 0.602 [95% CI 0.580,0.623; p < 0.001].ConclusionHigh TyG index levels appeared to be associated with an increased risk of MACEs in patients with AMI. The TyG index might be a valid predictor of cardiovascular outcomes of patients with AMI.Trial registrationRetrospectively registered. 相似文献
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目的:探讨钢铁企业工人心理资本在付出回报失衡、超负荷与工作倦怠关系中的调节与中介作用。方法随机选取某钢铁集团公司生产主线男性工人1700人,进行自填式问卷调查。调查内容包括一般情况、工作倦怠、付出回报失衡、超负荷、心理资本和感知的工作环境等。有效回收问卷1254份(73.76%)。采用分层回归分析检验调节作用,渐近—再抽样策略检验中介作用。结果心理资本对付出回报失衡与工作倦怠各维度之间的关系不存在调节作用,而对超负荷与情绪衰竭、玩世不恭之间关系有显著的正向调节作用;心理资本在付出回报失衡与情绪衰竭、玩世不恭之间关系中具有显著的中介作用,其中介效应量分别为5.84%和18.75%。结论心理资本水平高的工人,情绪衰竭和玩世不恭程度会随着超负荷的增加而明显上升;但心理资本水平低的工人,情绪衰竭和玩世不恭程度随着超负荷的增加而上升的趋势较弱。付出回报失衡降低钢铁工人心理资本存量进而导致情绪衰竭和玩世不恭。 相似文献
96.
K.S. Flannagan M. Ramírez-Zea A.V. Roman A.K. Das E. Villamor 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2018,28(12):1237-1244
Background and aims
Polyunsaturated fatty acids (PUFA) may play a role in the etiology of the metabolic syndrome (MetS). The aim of the study was to examine the associations of adipose tissue PUFA biomarkers with MetS among parents and children in Mesoamerica.Method and results
We conducted a cross-sectional study among 468 parents and 201 children aged 7–12 y from the capital cities of Guatemala, El Salvador, the Dominican Republic, Honduras, Nicaragua, Panama, Costa Rica, and Belize, and Tuxtla Gutiérrez in Mexico. We measured PUFA biomarkers in gluteal adipose tissue by gas chromatography. In adults, MetS was defined according to the National Cholesterol Education Program's Adult Treatment Panel III definition. In children, we created an age- and sex-standardized metabolic risk score using abdominal circumference, the homeostasis model of insulin resistance, blood pressure, serum HDL cholesterol, and triglycerides. We estimated prevalence ratios of MetS and mean differences in metabolic score across quartiles of PUFA using multivariable-adjusted Poisson and linear regression models, respectively. Among adults, MetS was associated with low alpha-linolenic acid (ALA), high eicosapentaenoic acid (EPA), and low gamma-linolenic acid (GLA). It was linearly, positively associated with dihomo-gamma-linolenic acid (DGLA) and estimated Δ6-desaturase (D6D) activity. Among children, the metabolic score was positively associated with docosapentaenoic acid (DPA), DGLA, and D6D activity.Conclusions
Among Mesoamerican adults, MetS prevalence is inversely associated with adipose tissue ALA and GLA, and positively associated with EPA, DGLA, and the D6D index. Among children, metabolic risk score is positively associated with DPA, DGLA, and the D6D index. 相似文献97.
目的 评估成人脊柱侧凸患者长时间步行前后整体和局部的矢状面影像学参数。方法 回顾性纳入2016年1月至2018年6月于海军军医大学(第二军医大学)长征医院就诊的98例成人脊柱侧凸患者,根据行走前矢状面参数将患者分为两组:代偿组(行走前矢状面平衡,矢状面躯干偏移<40 mm且骨盆倾斜角>20°)和失代偿组(行走前矢状面失平衡,矢状面躯干偏移≥ 40 mm且骨盆倾斜角>20°)。步行15 min前后拍摄站立位全脊柱正侧位X线片,测量脊柱矢状面参数,包括矢状面躯干偏移、胸椎后凸角、腰椎前凸角、骨盆入射角、骨盆倾斜角、骶骨倾斜角。比较两组步行15 min前后脊柱矢状面参数,并对每组步行15 min前后矢状面躯干偏移变化值与其余矢状面参数变化值进行相关性分析。结果 代偿组19例,其中女16例、男3例,平均年龄为(64.1±5.9)岁,BMI为(24.2±4.6)kg/m2;失代偿组79例,其中女67例、男12例,平均年龄为(66.7±7.2)岁,BMI为(24.9±5.1)kg/m2,两组患者性别构成比、年龄、BMI差异均无统计学意义(P均>0.05)。步行前,代偿组患者腰椎前凸角大于失代偿组(Z=2.784,P=0.003),骨盆入射角-腰椎前凸角和矢状面躯干偏移均小于失代偿组(Z=1.953,P=0.028;Z=3.815,P<0.01);两组间骨盆倾斜角、骶骨倾斜角、胸椎后凸角差异均无统计学意义(P均>0.05)。步行15 min后,两组间骨盆倾斜角、骶骨倾斜角、腰椎前凸角、胸椎后凸角、骨盆入射角-腰椎前凸角、矢状面躯干偏移差异均无统计学意义(P均>0.05)。与步行前比较,代偿组和失代偿组患者步行15 min后骶骨倾斜角、骨盆入射角-腰椎前凸角、矢状面躯干偏移均增大(代偿组Z=1.718、P=0.043,Z=2.198、P=0.015,Z=3.875、P<0.01;失代偿组Z=1.842、P=0.031,Z=1.943、P=0.021,Z=2.917、P=0.002),骨盆倾斜角和腰椎前凸角均减小(代偿组Z=1.639、P=0.047,Z=3.624、P<0.01;失代偿组Z=1.812、P=0.039,Z=3.893、P<0.01);失代偿组患者步行15 min后胸椎后凸角也较步行前增大(Z=2.287,P=0.012)。代偿组、失代偿组患者步行15 min前后矢状面躯干偏移变化值均与骨盆倾斜角变化值呈负相关(rs=-0.519、-0.625,P=0.024、0.001),与骶骨倾斜角变化值、腰椎前凸角变化值、骨盆入射角-腰椎前凸角变化值均呈正相关(代偿组rs=0.519、0.645、0.645,P均<0.05;失代偿组rs=0.625、0.407、0.407,P均<0.01)。结论 成人脊柱侧凸患者长时间行走后矢状面平衡的代偿机制逐渐减弱或消失,骨盆及脊柱伸肌肌群的疲劳可能是代偿机制消失的原因。对于初次就诊时矢状面躯干偏移<40 mm、骨盆倾斜角>20°的患者,建议在行走15 min后再次拍摄X线片重新评估是否存在潜在的矢状面失平衡。 相似文献
98.
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100.
FoxP3+ regulatory T (Treg) cells comprise a highly dynamic population that restrains autoreactivity. Although complete or long‐term depletion of Foxp3+CD4+ Treg cells in adult mice has been shown to result in chronic inflammation and autoimmune disease, the impact of transient Treg‐cell depletion on self‐reactive responses is poorly defined. A new study published in this issue of the European Journal of Immunology [Eur. J. Immunol. 2014. 44: 3621–3631] shows that, although transient depletion of Treg cells in mice is swiftly followed by recovery of Treg‐cell numbers, the “rebounded” population fails to maintain tolerance, culminating in severe autoimmune gastritis. This commentary explores new questions about the quantitative and qualitative aspects of Treg‐cell function in immunological tolerance raised by this study and others. 相似文献