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1.
Although randomized controlled trials demonstrated the long‐term efficacy of lifestyle interventions in overweight children, the effects of these interventions in clinical practice under real‐life conditions are largely unknown. One hundred twenty‐nine centers specialized in outpatient pediatric obesity care participated in this quality assessment. All patients presenting before the year 2006 for lifestyle intervention of at least 6 months duration in these institutions were analyzed in a 2‐year follow‐up. A total of 21,784 (45% male) overweight children and adolescents aged 2–20 years (mean BMI 30.4 kg/m2, mean SDS‐BMI 2.51, mean age 12.6 years) were included in the analysis. Based on an intention‐to‐treat analysis with variables set back to baseline in lost of follow‐up, 22% of the children reduced their SDS‐BMI after 6 months, 15% after 12 months, and 7% after 24 months, but only in 24, 17, and 8% of children, respectively, complete data were available. In the five treatment centers with the best outcome (518 patients), 83% of the children reduced their overweight after 6 months, 67% after 12 months, and 51% after 24 months. Under real‐life conditions, most treatment centers cannot prove the long‐term efficacy of their interventions due to high drop‐out rate or lack of documentation. Conversely, some institutions achieved a reduction of overweight in nearly the half of their patients 24 months after baseline demonstrating the great heterogeneity in outcome. To improve the effectiveness of lifestyle interventions in real‐life studying, the process and structure quality as well as their long‐term results is urgently needed.  相似文献   

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目的:应用速度向量成像(VVI)技术评价Valsalva动作对正常人左室扭转运动的影响,探讨其机理及临床意义。方法:应用VVI技术对30例正常人初始时与40 mmHg乏氏动作张力期10s时左室短轴心内膜及心外膜下心肌旋转(ROT)、扭转(TW)及扭矩(TOR)进行定量分析。结果:与初始时比较,40 mmHgValsalva动作张力期10s时左室舒张末容积(LVEDV)、收缩末容积(LVESV)及每搏量(SV)减低(P<0.001)而心率增快(P<0.001),射血分值(EF)没有变化(P>0.05);左室心尖部心内膜及心外膜下心肌收缩期峰值旋转均减低(P<0.05),而基底部ROT无明显变化(P>0.05),导致左室TW减低(P<0.05)而TOR没有变化(P>0.05)。结论:40 mmHg Valsalva动作可影响正常人左室ROT及TW。临床上Valsalva动作应尽量减少负荷压及持续时间,避免其对心脏功能的不利影响。  相似文献   

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Lithium‐ion batteries (LIBs) have dominated the portable electronics industry and solid‐state electrochemical research and development for the past two decades. In light of possible concerns over the cost and future availability of lithium, sodium‐ion batteries (SIBs) and other new technologies have emerged as candidates for large‐scale stationary energy storage. Research in these technologies has increased dramatically with a focus on the development of new materials for both the positive and negative electrodes that can enhance the cycling stability, rate capability, and energy density. Two‐dimensional (2D) materials are showing promise for many energy‐related applications and particularly for energy storage, because of the efficient ion transport between the layers and the large surface areas available for improved ion adsorption and faster surface redox reactions. Recent research highlights on the use of 2D materials in these future ‘beyond‐lithium‐ion’ battery systems are reviewed, and strategies to address challenges are discussed as well as their prospects.  相似文献   

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Spectral analysis has already been shown to be a powerful tool in the interrogation of lattice patterns, since it assumes no structural characteristics in the data (such as isotropy) prior to analysis. Here we extend the analysis to non‐lattice data for which both points and marks can exhibit spatial structure. Both distance‐ and spectral‐based measures are introduced, and theoretical comparisons are made between lattice and mark spectra. Simulated examples suggest a high degree of independence between point and mark spectra, and a real example is presented for the spatial structure of 584 tree locations and diameters at breast height of longleaf pine trees in southern Georgia.  相似文献   

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Objective: A systems dynamics computer model was developed to examine how the interactions between carbohydrate and fat metabolism influence body weight regulation. It reflects the operation of a two reservoir‐system: one representing the body's limited glycogen, and the other, its large fat reserves. The outflows from the reservoirs correspond to the oxidation of glucose and fat, whose relative contributions are affected by the size of the prevailing glycogen and fat reserves. Together, they meet the body's energy expenditure. Replenishments occur three times per day, in portions restoring total glycogen content to specific levels. A parameter mimicking the action of insulin is necessary to create realistic responses. Research Methods and Procedures: The model was run for 125‐day periods to establish the degree of adiposity for which rates of fat oxidation become commensurate with fat intake and the influence thereon of various dietary, environmental, lifestyle, and inherited variables. Results: Equivalent degrees of adiposity can be sustained under a variety of conditions. For instance, the impact on steady‐state body fat contents of a 10% increase or decrease in the energy provided by dietary fat is offset by a 26‐gram decrease or increase in mean glycogen levels. Discussion: Environmental factors such as food diversity, palatability, and availability can be expected to raise the range within which glycogen levels are habitually maintained. This restrains fat oxidation, until expansion of the fat mass is sufficient to promote fat oxidation to a rate commensurate with dietary fat intake. This metabolic leverage can explain why increased food offerings tend to raise the prevalence of obesity.  相似文献   

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Chiral nanostructures show macroscopic optical activity. Local optical activity and its handedness are not uniform in the nanostructure, and are spatially distributed depending on the shape of the nanostructure. In this study we fabricated curved chain nanostructures made of gold by connecting linearly two or more arc structures in a two‐dimensional plane. Spatial features of local optical activity in the chain structures were evaluated with near‐field circular dichroism (CD) imaging, and analyzed with the aid of classical electromagnetic simulation. The electromagnetic simulation predicted that local optical activity appears at inflection points where arc structures are connected. The handedness of the local optical activity was dependent on the handedness of the local chirality at the inflection point. Chiral chain structures have odd inflection points and the local optical activity distributed symmetrically with respect to structural centers. In contrast, achiral chain structures have even inflection points and showed antisymmetric distribution. In the near‐field CD images of fabricated chain nanostructures, the symmetric and antisymmetric distributions of local CD were observed for chiral and achiral chain structures, respectively, consistent with the simulated results. The handedness of the local optical activity was found to be determined by the handedness of the inflection point, for the fabricated chain structures having two or more inflection points. The local optical activity was thus governed primarily by the local chirality of the inflection points for the gold chain structures. The total effect of all the inflection points in the chain structure is considered to be a predominant factor that determines the macroscopic optical activity. Chirality 28:540–544, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   

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The development of two‐dimensional (2D) materials is experiencing a renaissance since the adventure of graphene. 2D materials typically exhibit strong in‐plane covalent bonding and weak out‐of‐plane van der Waals interactions through the interlayer gap. Opening 2D materials is an effective way to alter the physical and chemical properties, such as band gap, conductivity, optical property, thermoelectric property, photovoltaic property and superconductivity. A larger interlayer distance means more accessible active sites for catalysis, an ion‐accessible surface in the interlayer space, which may greatly enhance the performance of 2D materials for energy conversion and storage. Moreover, opening 2D materials by intercalation can change the band filling state and the Fermi level. This review mainly focuses on the opening of 2D materials and their subsequent applications in energy conversion and storage fields, expecting to promote the development of such a new class of materials, namely expanded 2D materials. The exciting progresses of these expanded materials made in both energy conversion and storage devices including solar cells, thermoelectric devices, electrocatalyst, supercapacitors and rechargeable batteries, is presented and discussed in depth. Furthermore, prospects and further developments in these exciting fields of the expanded 2D materials are also commented.  相似文献   

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《Endocrine practice》2023,29(6):471-477
ObjectiveTo investigate the incidence of corticotroph hyperplasia (CH) or lymphocyte infiltration in the pituitary of patients with obesity.MethodsThe pituitary and adrenal glands from 161 adult autopsies performed between 2010 and 2019 at our institution were reviewed. The clinical history, body mass index (BMI), and cause of death were recorded. Routine hematoxylin and eosin staining, reticulin staining, and immunohistochemical staining for adrenocorticotropic hormone, CD3, and CD20 were performed. The results were analyzed using the Fisher and chi-square statistics. Decedents were separated into 4 groups based on BMI (kg/m2): (1) lean (BMI, <25.0), (2) overweight (BMI, 25.0-29.9), (3) obesity class I (BMI, 30.0-34.9), and (4) obesity classes II to III (BMI, >34.9).ResultsCH/neoplasia was identified in 44 of 161 pituitary glands. Four (9.1%) of 53 lean patients had pituitary lesions, whereas 27.3% (12) of overweight, 22.7% (10) of obesity class I, and 40.9% (18) of obesity class II patients had hyperplasia (P < .0001). Small corticotroph tumors were identified in 15 patients; only 1 was a lean patient, and the tumor was associated with the Crooke hyaline change of nontumorous corticotrophs. The presence of CH and neoplasia was associated with adrenal cortical hyperplasia and lipid depletion. Microscopic foci of T and B lymphocytes were identified in the pituitaries of patients in each weight category; no independent association between BMI and lymphocyte inflammation was found.ConclusionOur data indicate an association between CH/neoplasia and obesity. It remains unclear whether obesity is the cause or effect of adrenocorticotropic hormone and cortisol excess.  相似文献   

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Two‐dimensional (2D) nanomaterials (i.e., graphene and its derivatives, transition metal oxides and transition metal dichalcogenides) are receiving a lot attention in energy storage application because of their unprecedented properties and great diversities. However, their re‐stacking or aggregation during the electrode fabrication process has greatly hindered their further developments and applications in rechargeable lithium batteries. Recently, rationally designed hierarchical structures based on 2D nanomaterials have emerged as promising candidates in rechargeable lithium battery applications. Numerous synthetic strategies have been developed to obtain hierarchical structures and high‐performance energy storage devices based on these hierarchical structure have been realized. This review summarizes the synthesis and characteristics of three styles of hierarchical architecture, namely three‐dimensional (3D) porous network nanostructures, hollow nanostructures and self‐supported nanoarrays, presents the representative applications of hierarchical structured nanomaterials as functional materials for lithium ion batteries, lithium‐sulfur batteries and lithium‐oxygen batteries, meanwhile sheds light particularly on the relationship between structure engineering and improved electrochemical performance; and provides the existing challenges and the perspectives for this fast emerging field.  相似文献   

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CD36 is a membrane receptor with a wide variety of functions, including the regulation of energy metabolism, fat storage, and adipocyte differentiation. To assess the relationship between CD36 gene single‐nucleotide polymorphisms (SNPs) and obesity in adolescents, we evaluated the relationship between CD36 SNPs and the risk of obesity in a case–control study composed of 307 obese (age = 15.0 ± 1.1 years) and 339 normal‐weight adolescents (age = 14.6 ± 1.1 years). To validate the results, we assessed the relation between the same SNPs and percentage of body fat (BF%) and BMI in 1,151 European adolescents (age = 14.8 ± 1.4 years). SNPs with a minor allele frequency >0.10 were selected to tag CD36. Genotyping was performed on an Illumina system. Four SNPs (rs3211867, rs3211883, rs3211908, and rs1527483) were associated with increased risk of obesity in the case–control study (odds ratio (OR) (95% confidence interval)): 1.96 (1.26–3.04], P = 0.003; 1.73 (1.16–2.59), P = 0.007; 2.42 (1.47–4.01), P = 0.0005 and 1.95 (1.25–3.05), P = 0.003, respectively). The same four SNPs were associated with higher BMI (P < 0.05) and BF% (P < 0.04) in the validation study. Further analyses identified a haplotype (frequency: 0.05) carrying the minor allele of these SNPs as being associated with obesity (OR: 2.28; P = 0.0008) in the case–control study and with excess adiposity (i.e., higher BF% (P = 0.03) and BMI (P = 0.04)) in the validation study. Our data suggest that genetic variability at the CD36 gene locus could be associated with body weight variability in European adolescents but these findings require replication.  相似文献   

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This study presents nationally representative estimates of individual and aggregate years‐of‐life‐lost (YLLs) associated with overweight and three categories of obesity separately by age, race, smoking status, and gender strata. Using proportional hazards analysis and data from the National Health Interview Survey (NHIS) Linked Mortality Files, we estimated life expectancies for each BMI strata and quantified YLLs by comparing differences between each strata and the normal BMI reference group. Our results provide further evidence that overweight and mild obesity are not associated with a reduction in life expectancy. However, higher BMI categories are associated with lower expected survival. In aggregate, excess BMI is responsible for ~95 million YLLs. White females account for more than two‐thirds of the aggregate YLLs. Unless something is done to reduce the rising prevalence of those with BMIs >35, or to mitigate the impact of obesity or its correlates on YLLs, expected life expectancy for US adults may decrease in the future.  相似文献   

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NMR Spectroscopy has been established as a major tool for identification and quantification of metabolites in a living system. Since the metabolomics era began, one‐dimensional NMR spectroscopy has been intensively employed due to its simplicity and quickness. However, it has suffered from an inevitable overlap of signals, thus leading to inaccuracy in identification and quantification of metabolites. Two‐dimensional (2D) NMR has emerged as a viable alternative because it can offer higher accuracy in a reasonable amount of time. We employed 1H,13C‐HSQC to profile metabolites of six different laboratory E. coli strains. We identified 18 metabolites and observed clustering of six strains according to their metabolites. We compared the metabolites among the strains, and found that a) the strains specialized for protein production were segregated; b) XL1‐Blue separated itself from others by accumulating amino acids such as alanine, aspartate, glutamate, methionine, proline, and lysine; c) the strains specialized for cloning purpose were spread out from one another; and d) the strains originating from B strain were characterized by succinate accumulation. This work shows that 2D‐NMR can be applied to identify a strain from metabolite analysis, offering a possible alternative to genetic analysis to identify E. coli strains.  相似文献   

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Objective: Low‐carbohydrate diets have become a popular alternative to standard diets for weight loss. Our aim was to compare the cost‐effectiveness of these two diets. Research Methods and Procedures: The patient population included 129 severely obese subjects (BMI = 42.9) from a randomized trial; participants had a high prevalence of diabetes or metabolic syndrome. We compared within‐trial costs, quality‐adjusted life years (QALYs), and the incremental cost‐effectiveness ratio (CER) for the two study groups. We imputed missing values for QALYs. The CER was bootstrapped to derive 95% confidence intervals and to define acceptability cut‐offs. We took a societal perspective for our analysis. Results: Total costs during the one year of the trial were $6742 ± 6675 and $6249 ± 5100 for the low‐carbohydrate and standard groups, respectively (p = 0.78). Participants experienced 0.64 ± 0.02 and 0.61 ± 0.02 QALYs during the one year of the study, respectively (p = 0.17 for difference). The point estimate of the incremental CER was $?1225/QALY (i.e., the low‐carbohydrate diet dominated the standard diet). However, in the bootstrap analysis, the wide spread of CERs caused the 95% confidence interval to be undefined. The probabilities that the low‐carbohydrate diet was acceptable, using cut‐offs of $50, 000/QALY, $100, 000/QALY, and $150, 000/QALY, were 72.4% 78.6%, and 79.8%, respectively. Discussion: The low‐carbohydrate diet was not more cost‐effective for weight loss than the standard diet in the patient population studied. Larger studies are needed to better assess the cost‐effectiveness of dietary therapies for weight loss.  相似文献   

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Objective: This study examined the extent to which consistency of self‐monitoring by participants and their parents was related to weight control over an initial period of 3 months within the context of a treatment program for morbidly obese low‐income minority adolescents. Research Methods and Procedures: Eighty‐three obese adolescents (mean age, 13.0 years; 51% boys; 92% African American; mean BMI, 43.0 kg/m2; mean BMI z‐score, 6.0) and at least one parent participated in a long‐term treatment program that included a very‐low‐fat dietary focus, weekly group cognitive‐behavior therapy, monthly nutrition education classes, a 12‐week physical therapy class, and medical monitoring. Results: Participants who self‐monitored on the majority of days compared with those who did not self‐monitor at all or who self‐monitored infrequently attended more sessions and generally lost more weight over the first 3 months. Although parents signed behavioral contracts committing to self‐monitor their own eating and exercising over the first month, only 12% did so. Nonetheless, participants whose parents self‐monitored were much more likely to self‐monitor consistently and lose weight during the first 3 months. Discussion: These results indicate that self‐monitoring is a cornerstone of successful weight control even for morbidly obese low‐income minority adolescents; targeting consistency of self‐monitoring among these high‐risk weight controllers and their parents should be just as important as it is for more affluent and less overweight adolescents.  相似文献   

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