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Neuroimaging studies indicate that children with attention‐deficit/hyperactivity disorder (ADHD) present alterations in several functional networks of the sensation‐to‐cognition spectrum. These alterations include functional overconnectivity within sensory regions and underconnectivity between sensory regions and neural hubs supporting higher order cognitive functions. Today, it is unknown whether this same pattern of alterations persists in adult patients with ADHD who had never been medicated for their condition. The aim of the present study was to assess whether medication‐naïve adults with ADHD presented alterations in functional networks of the sensation‐to‐cognition spectrum. Thirty‐one medication‐naïve adults with ADHD and twenty‐two healthy adults underwent resting‐state functional magnetic resonance imaging (rs‐fMRI). Stepwise functional connectivity (SFC) was used to characterize the pattern of functional connectivity between sensory seed regions and the rest of the brain at direct, short, intermediate, and long functional connectivity distances, thus covering the continuum from the sensory input to the neural hubs supporting higher order cognitive functions. As compared to controls, adults with ADHD presented increased SFC degree within primary sensory regions and decreased SFC degree between sensory seeds and higher order integration nodes. In addition, they exhibited decreased connectivity degree between sensory seeds and regions of the default‐mode network. Consistently, the higher the score in clinical severity scales the lower connectivity degree between seed regions and the default mode network.  相似文献   
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Exercise improves objective measures of physical function in individuals on hemodialysis, but its effect on patient‐reported outcomes (PROs) is largely unknown. We performed a scoping review to characterize the existing knowledge base on exercise and PROs in dialysis patients to make recommendations for future research. We searched Medline, Embase, Cochrane Database of Systematic Reviews; Cochrane Central Register of Controlled Trials, CINAHL, and SPORT Discus from inception to November 28, 2018 and then screened results for randomized controlled trials comparing aerobic/resistance exercise, or both, with no exercise in individuals on dialysis that reported results of any PRO. Of 1374 eligible studies, 25 studies met inclusion criteria. Study interventions included aerobic exercise (11 intradialytic and 3 home‐based trials); intradialytic resistance exercise (seven studies) and combined aerobic and resistance exercise (six intradialytic and one facility‐based trial). The PROs measured included health‐related quality of life (n = 19), depression (n = 6), anxiety (n = 3), symptom burden (n = 4), sleep quality (n = 2), restless legs syndrome (n = 2), disability (n = 2), and self‐reported physical activity level (n = 4). Only five studies included a PRO as a primary outcome. Studies primarily used broad/generic measures of health‐related quality of life and the effect of exercise on symptoms remains relatively unexplored, particularly in peritoneal dialysis populations. Although limited, the role of exercise in improving restless legs was consistent and is a promising outcome for future study. A critical step to improving the quality of the research on this topic includes the use of validated and consistent PRO measures.  相似文献   
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目的 探讨Stealth穿透型参考电离室在立体定向放疗的相对剂量学中的实际应用价值。方法 在IBABlue Phantom水箱中使用2种方法对于配备Brianlab圆锥形限光筒的VarianNovalis 6 MV光子射线进行相对剂量测定。第1种方法无Stealth穿透型参考电离室,单独使用SFD半导体电离室配合“Step by Step”逐点测量;第2种方法有Stealth穿透型参考电离室,使用SFD半导体电离室配合“Continuous”连续测量。测量内容包括直径4、15 mm限光筒下中心轴百分深度剂量(PDD)曲线和离轴剂量比(OAR)曲线并记录每次测量所需时间。结果 对于配备直径4 mm及15 mm的X刀限光筒的6 MV光子射线,逐点测量和连续测量所得的射野中心轴PDD曲线及10 cm深度处OAR曲线吻合度较好,差异在1%以内。连续测量PDD曲线及OAR曲线所需时间大幅缩短,较逐点测量平均缩短为13.1%和20.7%。结论 Stealth穿透型参考电离室在立体定向放疗相对剂量学中的应用可以在保证剂量结果准确性前提下大幅提高测量效率。  相似文献   
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An accurate assessment of time since fracture is an essential component of abuse and death investigations; however, little evidence-based research exists on dating fractures, especially those of the cranial vault. This is primarily due to difficulties in procuring human fracture specimens of known posttraumatic survival times. The aim of this article is to introduce a new database through which limitations imposed by sample procurement may be mitigated. The Repository of Antemortem Injury Response (REPAIR) is a digitally accessible database of cranial vault fractures of known ages with extensive contextual information and visual documentation in the form of photography, radiography, and histological photomicrographs. This repository is a multifunctional tool that serves as a case submission portal for cranial fractures of known posttraumatic survival time, a sample database for research on fracture healing and rates of repair, a resource for comparative assessments of cranial fractures in forensic casework, and an educational tool for healing fracture histomorphology.

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Background and aimsDespite using sensor-augmented pump therapy (SAPT) with predictive low-glucose management (PLGM), hypoglycemia is still an issue in patients with type 1 Diabetes (T1D). Our aim was to determine factors associated with clinically significant hypoglycemia (<54 mg/dl) in persons with T1D treated with PLGM-SAPT.Methodology: This is a multicentric prospective real-life study performed in Colombia, Chile and Spain. Patients with T1D treated with PLGM-SAPT, using sensor ≥70% of time, were included. Data regarding pump and sensor use patterns and carbohydrate intake from 28 consecutive days were collected. A bivariate and multivariate Poisson regression analysis was carried out, to evaluate the association between the number of events of <54 mg/dl with the clinical variables and patterns of sensor and pump use.Results188 subjects were included (41 ± 13.8 years-old, 23 ± 12 years disease duration, A1c 7.2% ± 0.9). The median of events <54 mg/dl was four events/patient/month (IQR 1–10), 77% of these events occurred during day time. Multivariate analysis showed that the number of events of hypoglycemia were higher in patients with previous severe hypoglycemia (IRR1.38; 95% CI 1.19–1.61; p < 0.001), high glycemic variability defined as Coefficient of Variation (CV%) > 36% (IRR 2.09; 95%CI 1.79–2.45; p < 0.001) and hypoglycemia unawareness. A protector effect was identified for adequate sensor calibration (IRR 0.77; 95%CI 0.66–0.90; p:0.001), and the use of bolus wizard >60% (IRR 0.74; 95%CI 0.58–0.95; p:0.017).ConclusionIn spite of using advanced SAPT, clinically significant hypoglycemia is still a non-negligible risk. Only the identification and intervention of modifiable factors could help to prevent and reduce hypoglycemia in clinical practice.  相似文献   
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Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique increasingly used to modulate neural activity in the living brain. In order to establish the neurophysiological, cognitive or clinical effects of tDCS, most studies compare the effects of active tDCS to those observed with a sham tDCS intervention. In most cases, sham tDCS consists in delivering an active stimulation for a few seconds to mimic the sensations observed with active tDCS and keep participants blind to the intervention. However, to date, sham-controlled tDCS studies yield inconsistent results, which might arise in part from sham inconsistencies. Indeed, a multiplicity of sham stimulation protocols is being used in the tDCS research field and might have different biological effects beyond the intended transient sensations. Here, we seek to enlighten the scientific community to this possible confounding factor in order to increase reproducibility of neurophysiological, cognitive and clinical tDCS studies.  相似文献   
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