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The aim of this study was to evaluate the effectiveness of a practice magnetic resonance unit, in preparing children to undergo magnetic resonance procedures without general anaesthesia (GA) or sedation. The records of children who attended the practice MRI between February 2002 and April 2004 were retrospectively reviewed. Each record was assessed as to whether the child had passed or failed the practice MRI intervention. Those children who were considered to have passed and were proceeded to a clinical non‐GA MRI had the report of the clinical scan reviewed. If the scan had been reported as non‐diagnostic because of movement artefact it was classified as a failed scan, otherwise it was considered a pass. One hundred and thirty‐four children undertook a practice MRI (age range 4.1–16.1 years, median age 7.7 years, 47% boys) and 120/134 (90%) passed the practice session. In all, 117/120 (98%) subsequently had a clinical non‐GA MRI and 110/117 (94%) passed (median age 7.8 years, 47% boys). Preparation is a safe and effective method to reduce the need for sedation and GA in children undergoing a clinical MRI scan. It provides a positive medical experience for children, parents and staff, and results in cost savings for the hospital.  相似文献   
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Glial cell line-derived neurotrophic factor (GDNF) plays a critical role in neurodevelopment and survival of midbrain dopaminergic and spinal motor neurons in vitro and in vivo. The biological actions of GDNF are mediated by a two-receptor complex consisting of a glycosylphosphatidylinositol-linked cell surface molecule, the GDNF family receptor alpha 1 (GFR alpha 1), and receptor protein tyrosine kinase Ret. Although structural analysis of GDNF has been extensively examined, less is known about the structural basis of GFR alpha 1 function. In this study, based on evolutionary trace method and relative solvent accessibility prediction of residues, a set of trace residues that are solvent-accessible was selected for site-directed mutagenesis. A series of GFR alpha 1 mutations was made, and PC12 cell lines stably expressing different GFR alpha 1 mutants were generated. According to the survival and differentiation responses of these stable PC12 cells upon GDNF stimulation and the GDNF- GFR alpha 1-Ret interaction assay, residues 152NN153, Arg259, and 316SNS318 in the GFR alpha 1 central region were found to be critical for GFR alpha 1 binding to GDNF and eliciting downstream signal transduction. The single mutation R259A in the GFR alpha 1 molecule simultaneously lost its binding ability to GDNF and Ret. However N152A/N153A or S316A/N317A/ S318A mutation in the GFR alpha 1 molecule still retained the ability to bind with Ret. These findings suggest that distinct structural elements in GFR alpha 1 may be involved in binding to GDNF and Ret.  相似文献   
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Endothelial dysfunction is a key feature of preeclampsia and may contribute to increased cardiovascular disease risk years after pregnancy. Flow-mediated dilation (FMD) is a non-invasive endothelial function test that predicts cardiovascular event risk. New protocols allow researchers to measure three components of the FMD response: FMD, low flow-mediated constriction, and shear stimulus. This review encourages researchers to think beyond “low FMD” by examining how these three components may provide additional insights into the mechanisms and location of vascular dysfunction. The review then examines what FMD studies reveal about vascular dysfunction in preeclampsia while highlighting opportunities to gain greater mechanistic insight from new protocols. Studies using traditional protocols show that FMD is low in mid-pregnancy prior to preeclampsia, at diagnosis, and for 3 years post-partum. However, FMD returns to normal by 10 years post-partum. Studies using new protocols are needed to gain more mechanistic insight.  相似文献   
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Background: According to clinical practice guidelines, transarterial chemoembolization (TACE) is the standard treatment modality for patients with intermediate-stage hepatocellular carcinoma (HCC). Early prediction of treatment response can help patients choose a reasonable treatment plan. This study aimed to investigate the value of the radiomic-clinical model in predicting the efficacy of the first TACE treatment for HCC to prolong patient survival.Methods: A total of 164 patients with HCC who underwent the first TACE from January 2017 to September 2021 were analyzed. The tumor response was assessed by modified response evaluation criteria in solid tumors (mRECIST), and the response of the first TACE to each session and its correlation with overall survival were evaluated. The radiomic signatures associated with the treatment response were identified by the least absolute shrinkage and selection operator (LASSO), and four machine learning models were built with different types of regions of interest (ROIs) (tumor and corresponding tissues) and the model with the best performance was selected. The predictive performance was assessed with receiver operating characteristic (ROC) curves and calibration curves.Results: Of all the models, the random forest (RF) model with peritumor ( + 10 mm) radiomic signatures had the best performance [area under ROC curve (AUC) = 0.964 in the training cohort, AUC = 0.949 in the validation cohort]. The RF model was used to calculate the radiomic score (Rad-score), and the optimal cutoffvalue (0.34)was calculatedaccordingto theYouden’sindex. Patientswere thendivided intoa high-risk group (Rad-score > 0.34) and a low-risk group (Rad-score ≤0.34), and a nomogram model was successfully established to predict treatment response. The predicted treatment response also allowed for significant discrimination of Kaplan-Meier curves. Multivariate Cox regression identified six independent prognostic factors for overall survival, including male [hazard ratio (HR) = 0.500, 95% confidence interval (CI): 0.260–0.962, P = 0.038], alpha-fetoprotein (HR = 1.003, 95% CI: 1.002–1.004, P < 0.001), alanine aminotransferase (HR = 1.003, 95% CI: 1.0 01–1.0 05, P = 0.025), performance status (HR = 2.400, 95% CI: 1.20 0–4.80 0, P = 0.013), the number of TACE sessions (HR = 0.870, 95% CI: 0.780–0.970, P = 0.012) and Rad-score (HR = 3.480, 95% CI: 1.416–8.552, P = 0.007).Conclusions: The radiomic signatures and clinical factors can be well-used to predict the response of HCC patients to the first TACE and may help identify the patients most likely to benefit from TACE.  相似文献   
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Background: Wernicke encephalopathy (WE) is an acute neurological disease resulting from vitamin B1 deficiency, and there are only very few case reports of WE after liver transplantation. The present study aimed to investigate the clinical characteristics, etiology, magnetic resonance imaging (MRI) features, treatment and prognosis of patients with WE after liver transplantation.Methods: Twenty-three patients with WE after liver transplantation from the First Affiliated Hospital, Zhejiang University School of Medicine and Jiangxi Provincial People’s Hospital between January 2011 and December 2021 were retrospectively analyzed.Results: Among the 23 patients diagnosed with WE after liver transplantation, 6 (26%) had a classic triad of impaired consciousness, oculomotor palsy and ataxia, and 17 (74%) had two features. The misdiagno- sis rate was 65%. After treatment with high-dose vitamin B1, 19 (83%) patients showed improvement, whereas 4 (17%) showed no improvement, including 3 with residual short-term memory impairments and 1 with residual spatial and temporal disorientation and ataxia.Conclusions: The misdiagnosis rate is high in the early stage of WE, and the prognosis is closely associated with whether WE is diagnosed early and treated timely. High-dose glucose or glucocorticoids can trigger WE and cannot be administered before vitamin B1 treatment. Vitamin B1 is suggested to be used as a prophylactic treatment for patients with WE after liver transplantation.  相似文献   
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Racial concordance has been identified as a potential strategy to improve the perinatal health of Black women and birthing people by mitigating implicit bias and improving mutual trust, healthy communication, and satisfaction. In a recent article published in BIRTH: Issues in Perinatal Care, Bogdan-Lovis et al. surveyed 200 Black women to determine whether they possessed a race and gender practitioner preference for their birth practitioner and examined whether race and gender concordance was associated with greater birth satisfaction and perceived respect, trust, practitioner competence, empathy, and use of inclusive communication. In this commentary, written by a group of Black midwives, we respond to the study and offer a vision for race-concordant care that encompasses cultural safety provided in a community-based setting.  相似文献   
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