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331.
Accurate spatial correspondence between template and subject images is a crucial step in neuroimaging studies and clinical applications like stereotactic neurosurgery. In the absence of a robust quantitative approach, we sought to propose and validate a set of point landmarks, anatomical fiducials (AFIDs), that could be quickly, accurately, and reliably placed on magnetic resonance images of the human brain. Using several publicly available brain templates and individual participant datasets, novice users could be trained to place a set of 32 AFIDs with millimetric accuracy. Furthermore, the utility of the AFIDs protocol is demonstrated for evaluating subject‐to‐template and template‐to‐template registration. Specifically, we found that commonly used voxel overlap metrics were relatively insensitive to focal misregistrations compared to AFID point‐based measures. Our entire protocol and study framework leverages open resources and tools, and has been developed with full transparency in mind so that others may freely use, adopt, and modify. This protocol holds value for a broad number of applications including alignment of brain images and teaching neuroanatomy.  相似文献   
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This study aimed to explore the association between schoolchildren's oral health-related quality of life (OHRQoL) and the school-related social environment (contextual factors). A cross-sectional study was performed with 1,211 children, aged 8–12 yr, from 20 private and public schools. Sociodemographic information was collected from a questionnaire given to parents, and children were interviewed using the Child Perceptions Questionnaire (CPQ) and examined for oral health conditions. Contextual variables were obtained from school coordinators regarding the social environment. Data analysis was performed through multilevel Poisson regression. A high negative impact on OHRQoL was found for participants who were girls, older, had very severe malocclusion, had dental trauma and caries, and had mothers with less schooling. A negative impact on OHRQoL was also found for children who attended schools in which police security was required (rate ratios [RR] = 1.11; 95% CI: 1.01–1.22) and in which violence among students occurred in the last year (RR = 1.17; 95% CI: 1.02–1.35). The need for police security was associated with a negative impact on the emotional well-being domain, and violence among students was associated with negative impact on the oral symptoms, functional limitations, and social well-being domains. Children in healthier environments have better OHRQoL.  相似文献   
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Clinical Oral Investigations - The aim of this study was to evaluate the degree of conversion, ultimate tensile strength, cell viability, and oxidative stress of two different ternary initiation...  相似文献   
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Background/aims: The frequency of HLA markers associated with rapid progression to AIDS was evaluated in Brazilian patients with AIDS exhibiting or not toxoplasmic retinochoroiditis (TRC). Methods: 98 AIDS patients (25 with TRC, 43 with anti-T. gondii antibodies but without TCR, and 30 without anti-T. gondii antibodies and without TCR) were studied. Results: The HLA-B35 was significantly increased in TRC group (p = 0.0038). Conclusion: The presence of HLA-B35 may simultaneously predispose to progression to AIDS and TRC.  相似文献   
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The biological activity of the multifunctional cytokine interleukin-1 (IL-1) is mediated by its receptors. The aim of this study was to determine if an association exists between single nucleotide polymorphisms (SNPs) in the IL-1 type 1 and 2 receptor genes (IL1R1 and IL1R2) and the expression level of membrane-bound IL1Rs on subpopulations of mononuclear cells or serum levels of soluble IL-1 receptors. It was observed that healthy individuals with the genotype TT in SNP rs2234650:C>T had a lower percentage of intact CD14+ monocytes expressing IL1R1 on their surface. The SNP rs4141134:T>C in IL1R2 has also been associated with the percentage of intact CD3+ T cells expressing IL1R2. Furthermore, individuals carrying the CC allele of SNP rs4141134:T>C and the TT allele of SNP rs2071008:T>G in IL1R2 had a lower density of IL1R2s on the surface of CD14+ monocytes in lipopolysaccharide (LPS)-stimulated PBMC cultures. In summary, this study demonstrated that IL-1 receptor gene polymorphisms could be one of the factors influencing the expression of membrane-bound IL-1 receptors (IL1R) on immunocompetent cells.  相似文献   
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Chehab  FF; Winterhalter  KH; Kan  YW 《Blood》1989,74(2):852-854
We characterized the molecular defect in a Swiss patient with a spontaneous beta-thalassemia mutation. Cloning and DNA sequencing of her beta-globin gene revealed a new frameshift mutation due to a single nucleotide deletion at codon 64 of the beta-globin gene. Restriction site polymorphism showed that the mutation arose on her paternal chromosome. Direct sequencing of a polymerase chain reaction amplified DNA segment showed absence of the lesion in both alleles of her father's beta-globin gene and confirmed the spontaneous nature of this mutation.  相似文献   
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