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51.
目的:探讨MRI在浸润性小叶癌(ILC)术前诊断中的应用价值,并评估乳腺密度对其影响。方法:选取75例术前30天内行MRI检查的I-Ⅲ期ILC患者列入本项研究,根据腺体含量评估乳腺密度,在MRI下测量肿瘤大小,并对比其与病理大小的一致性。结果:75例入组患者中26例(34.7%)患者经MRI评估发现新的可疑病灶,20例(26.7%)患者改变了手术方式。高密度乳腺型患者额外病灶检出率明显高于低密度乳腺型患者(51.6% vs 22.7%,P=0.010)。MRI评估肿瘤大小在低密度乳腺型患者中容易被低估(36.4% vs 12.9%,P=0.024),在高密度乳腺型患者中容易被高估(6.8% vs 29.0%,P=0.010),但两组患者与病理大小一致性的比例无明显差异。结论:ILC患者术前乳腺MRI检查能够提高额外恶性肿瘤的检出率,而乳腺密度是影响MRI评估的重要因素。  相似文献   
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PurposeEffective written communication directly affects health care outcomes. Since 2016, the complex language of state-mandated breast density notifications (BDNs) has been challenged, because it is perceived to be beyond the comprehension of most patients. The aim of this study was to assess whether a revised BDN written at a lower reading grade level improves understanding compared with the current state-mandated BDN.MethodsA revised notification with similar content to the current state-mandated BDN was developed. Both notifications were presented to patients for direct comparison, using a paper survey asking questions that evaluated patients’ perceptions and convictions associated with breast density. Surveys were distributed at four outpatient imaging centers to screening mammography patients.ResultsThe current BDN’s mean readability metric was 13.4, and that of the revised BDN was 6.6. Five hundred surveys were analyzed. Survey data demonstrated that 56.6% of all women perceived that dense breast tissue results indicated a “high” associated lifetime breast cancer risk from the current state-mandated BDN compared with only 2.2% with the revised notification (P < .001). Nearly all women were more likely to initiate discussions with their providers regarding their breast tissue density after reading the revised notification (96.0%) as opposed to the current state-mandated BDN (32.8%; P < .001).ConclusionsA significant portion of women misinterpret the intended messages of the current state-mandated BDN. Thus, a revised notification at a lower reading grade level may improve understanding of breast density, leading to improved individualized breast cancer screening for women with dense breasts.  相似文献   
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BackgroundSome chronic obstructive pulmonary disease (COPD) patients develop hypoxemia with disease progression, with some even requiring long-term oxygen therapy (LTOT). Lung function, especially diffusing capacity, and the annual decline in PaO2, are reported to be predictive factors of chronic respiratory failure. However, the association between lung morphometry evaluated using computed tomography (CT) images and LTOT initiation is unknown.MethodsWe retrospectively evaluated the relationship between clinical indices, including pulmonary function, body mass index (BMI), and CT parameters, at baseline and LTOT initiation in two prospective COPD cohorts. In the Nara Medical University cohort (n = 76), the low attenuation area (LAA) and its fractal dimension (fractal D) were adapted as the indices for parenchymal destruction in CT images. The association between these CT measurements and LTOT initiation was replicated in the Kyoto University cohort (n = 130).ResultsIn the Nara Medical University cohort, lower BMI (hazard ratio [HR]:0.70, p = 0.006), lower % diffusing capacity (%DLCO) (HR: 0.92, p = 0.006), lower %DLCO/VA (HR, 0.90, p = 0.008), higher RV/TLC (HR, 1.26, p = 0.012), higher LAA% (HR: 1.18, p = 0.001), and lower fractal D (HR: 3.27 × 10?8, p < 0.001) were associated with LTOT initiation. Multivariate analysis in the Kyoto University cohort confirmed that lower %DLCO and lower fractal D were independently associated with LTOT initiation, whereas LAA% was not.ConclusionFractal D, which is the index for morphometric complexity of LAA in CT analysis, is predictive of LTOT initiation in COPD patients.  相似文献   
56.
《Brain stimulation》2022,15(2):337-351
BackgroundAbnormalities in frontoparietal network (FPN) were observed in many neuropsychiatric diseases including substance use disorders. A growing number of studies are using dual-site-tACS with frontoparietal synchronization to engage this network. However, a computational pathway to inform and optimize parameter space for frontoparietal synchronization is still lacking. In this case study, in a group of participants with methamphetamine use disorders, we proposed a computational pathway to extract optimal electrode montage while accounting for stimulation intensity using structural and functional MRI.MethodsSixty methamphetamine users completed an fMRI drug cue-reactivity task. Four main steps were taken to define electrode montage and adjust stimulation intensity using 4x1 high-definition (HD) electrodes for a dual-site-tACS; (1) Frontal seed was defined based on the maximum electric fields (EF) predicted by simulation of HD montage over DLPFC (F3/F4 in EEG 10–10), (2) frontal seed-to-whole brain context-dependent correlation was calculated to determine connected regions to frontal seeds, (3) center of connected cluster in parietal cortex was selected as a location for placing the second set of HD electrodes to shape the informed montage, (4) individualized head models were used to determine optimal stimulation intensity considering underlying brain structure. The informed montage was compared to montages with large electrodes and classic frontoparietal HD montages (F3-P3/F4-P4) in terms of tACS-induced EF and ROI-to-ROI task-based/resting-state connectivity.ResultsCompared to the large electrodes, HD frontoparietal montages allow for a finer control of the spatial peak fields in the main nodes of the FPN at the cost of lower maximum EF (large-pad/HD: max EF[V/m] = 0.37/0.11, number of cortical sub-regions that EF exceeds 50% of the max = 77/13). For defining stimulation targets based on EF patterns, using group-level head models compared to a single standard head model results in comparable but significantly different seed locations (6.43 mm Euclidean distance between the locations of the frontal maximum EF in standard-space). As expected, significant task-based/resting-state connections were only found between frontal-parietal locations in the informed montage. Cue-induced craving score was correlated with frontoparietal connectivity only in the informed montage (r = ?0.24). Stimulation intensity in the informed montage, and not in the classic HD montage, needs 40% reduction in the parietal site to reduce the disparity in EF between stimulation sites.ConclusionThis study provides some empirical insights to montage and dose selection in dual-site-tACS using individual brain structures and functions and proposes a computational pathway to use head models and functional MRI to define (1) optimum electrode montage for targeting FPN in a context of interest (drug-cue-reactivity) and (2) proper transcranial stimulation intensity.  相似文献   
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A comparative study involving bimetallic nickel catalysts designed from disubstituted N,N,N′,N′‐tetra(diphenylphosphanylmethyl)benzene diamine bridging ligands is reported. Catalyst behavior is explored in the Kumada catalyst‐transfer polymerization (KCTP) using poly(3‐hexylthiophene) (P3HT) as the model system. The success of a controlled polymerization is monitored by analyzing monomer conversion, degree of polymerization, end‐group identity, and molecular weight distribution. The characterization of P3HT obtained from KCTP initiated with the bimetallic catalysts shows chain‐growth behavior; however, the presence of Br/Br end‐groups and broader molecular weight distribution reveals a reduced controlled polymerization compared to the commonly employed Ni(dppp)Cl2. The observed increase in intermolecular chain transfer and termination processes in KCTP initiation with the bimetallic catalysts can be attributed to a weaker Ni(0)‐π‐aryl complex interaction, which is caused by increased steric crowding of the coordination sphere.  相似文献   
58.
《Journal of endodontics》2020,46(10):1455-1464
IntroductionThe aim of this study was to investigate whether mineral trioxide aggregate (MTA) can be modified with caffeic acid (CA) to form caffeic acid/mineral trioxide aggregate (CAMTA) cement and to evaluate its physicochemical and biological properties as well as its capability in immune suppression and angiogenesis.MethodsMTA was immersed in trishydroxymethyl aminomethane buffer with CA to allow coating onto MTA powders. X-ray diffractometry and tensile stress-strain tests were conducted to assess for physical characteristics of CAMTA and to evaluate for successful modification of MTA. Then, the CAMTA cement was immersed in simulated body fluid to evaluate its hydroxyapatite formation capabilities and Si release profiles. In addition, RAW 264.7 cells and human dental pulp stem cells were used to evaluate CAMTA’s immunosuppressive capabilities and cell responses, respectively. hDPSCs were also used to assess CAMTA’s angiogenic capabilities.ResultsThe X-ray diffractometry results showed that CA can be successfully coated onto MTA without disrupting or losing MTA’s original structural properties, thus allowing us to retain the initial advantages of MTA. CAMTA was shown to have higher mechanical properties compared with MTA and had rougher pitted surfaces, which were hypothesized to lead to enhanced adhesion, proliferation, and secretion of angiogenic- and odontogenic-related proteins. In addition, it was found that CAMTA was able to enhance hydroxyapatite formation and immunosuppressive capabilities compared with MTA.ConclusionsCAMTA cements were found to have improved physicochemical and biological characteristics compared with their counterpart. In addition, CAMTA cements had enhanced odontogenic, angiogenic, and immunosuppressive properties compared with MTA. All of the results of this study proved that CAMTA cements could be a biomaterial for future clinical applications and tissue engineering use.  相似文献   
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Congenital diarrhea and enteropathies (CODEs) are a group of monogenic disorders that often present with severe diarrhea in the first weeks of life. Enteric anendocrinosis (EA), an extremely rare cause of CODE, is characterized by a marked reduction of intestinal enteroendocrine cells (EC). EA is associated with recessively inherited variants in Neurogenin-3 (NEUROG3) gene. Here we investigate a case of a male infant who presented with mysterious severe malabsorptive diarrhea since birth. Thorough clinical assessments and laboratory tests were successful to exclude the majority of differential diagnosis categories. However, the patient's diagnosis was not established until the genetic test using whole-exome sequencing (WES) was performed. We identified a novel homozygous missense disease-causing variant (DCV) in NEUROG3 (c.413C>G, p.Thr138Arg). Moreover, molecular dynamic simulation analysis showed that (p.Thr138Arg) led to a global change of the NEUROG3 orientation affecting its DNA binding capacity. To the best of our knowledge, this is the first time to apply WES to reach a differential diagnosis of patients with CODEs. Our study not only expands our knowledge about NEUROG3 variants and their clinical consequences but also proves that WES is a very effective tool for the diagnosis of CODEs. This might be of value in early diagnosis of diseases and prenatal CODEs detection.  相似文献   
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For children with Developmental Coordination Disorder (DCD), the real-time coupling between frontal executive function and online motor control has not been explored despite reported deficits in each domain. The aim of the present study was to investigate how children with DCD enlist online control under task constraints that compel the need for inhibitory control. A total of 129 school children were sampled from mainstream primary schools. Forty-two children who met research criteria for DCD were compared with 87 typically developing controls on a modified double-jump reaching task. Children within each skill group were divided into three age bands: younger (6–7 years), mid-aged (8–9), and older (10–12). Online control was compared between groups as a function of trial type (non-jump, jump, anti-jump). Overall, results showed that while movement times were similar between skill groups under simple task constraints (non-jump), on perturbation (or jump) trials the DCD group were significantly slower than controls and corrected trajectories later. Critically, the DCD group was further disadvantaged by anti-jump trials where inhibitory control was required; however, this effect reduced with age. While coupling online control and executive systems is not well developed in younger and mid-aged children, there is evidence of age-appropriate coupling in older children. Longitudinal data are needed to clarify this intriguing finding. The theoretical and applied implications of these results are discussed.  相似文献   
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