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1.
Task‐based functional neuroimaging methods are increasingly being used to identify biomarkers of treatment response in psychiatric disorders. To facilitate meaningful interpretation of neural correlates of tasks and their potential changes with treatment over time, understanding the reliability of the blood‐oxygen‐level dependent (BOLD) signal of such tasks is essential. We assessed test–retest reliability of an emotional conflict task in healthy participants collected as part of the Canadian Biomarker Integration Network in Depression. Data for 36 participants, scanned at three time points (weeks 0, 2, and 8) were analyzed, and intra‐class correlation coefficients (ICC) were used to quantify reliability. We observed moderate reliability (median ICC values between 0.5 and 0.6), within occipital, parietal, and temporal regions, specifically for conditions of lower cognitive complexity, that is, face, congruent or incongruent trials. For these conditions, activation was also observed within frontal and sub‐cortical regions, however, their reliability was poor (median ICC < 0.2). Clinically relevant prognostic markers based on task‐based fMRI require high predictive accuracy at an individual level. For this to be achieved, reliability of BOLD responses needs to be high. We have shown that reliability of the BOLD response to an emotional conflict task in healthy individuals is moderate. Implications of these findings to further inform studies of treatment effects and biomarker discovery are discussed.  相似文献   
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Contagious caprine pleuropneumonia (CCPP) is a highly contagious disease caused by Mycoplasma capricolum subsp. capripneumoniae that affects goats in Africa and Asia. Current available methods for the diagnosis of Mycoplasma infection, including cultivation, serological assays, and PCR, are time-consuming and require fully equipped stationary laboratories, which make them incompatible with testing in the resource-poor settings that are most relevant to this disease. We report a rapid, specific, and sensitive assay employing isothermal DNA amplification using recombinase polymerase amplification (RPA) for the detection of M. capricolum subsp. capripneumoniae. We developed the assay using a specific target sequence in M. capricolum subsp. capripneumoniae, as found in the genome sequence of the field strain ILRI181 and the type strain F38 and that was further evidenced in 10 field strains from different geographical regions. Detection limits corresponding to 5 × 103 and 5 × 104 cells/ml were obtained using genomic DNA and bacterial culture from M. capricolum subsp. capripneumoniae strain ILRI181, while no amplification was obtained from 71 related Mycoplasma isolates or from the Acholeplasma or the Pasteurella isolates, demonstrating a high degree of specificity. The assay produces a fluorescent signal within 15 to 20 min and worked well using pleural fluid obtained directly from CCPP-positive animals without prior DNA extraction. We demonstrate that the diagnosis of CCPP can be achieved, with a short sample preparation time and a simple read-out device that can be powered by a car battery, in <45 min in a simulated field setting.  相似文献   
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BackgroundNeoadjuvant yttrium-90 transarterial radioembolization (TARE) is increasingly being used as a strategy to facilitate resection of otherwise unresectable tumors due to its ability to generate both tumor response and remnant liver hypertrophy. Perioperative outcomes after the use of neoadjuvant lobar TARE remain underinvestigated.MethodsA single center retrospective review of patients who underwent lobar TARE prior to major hepatectomy for primary or metastatic liver cancer between 2007 and 2018 was conducted. Baseline demographics, radioembolization parameters, pre- and post-radioembolization volumetrics, intra-operative surgical data, adverse events, and post-operative outcomes were analyzed.ResultsTwenty-six patients underwent major hepatectomy after neoadjuvant lobar TARE. The mean age was 58.3 years (17–88 years). 62% of patients (n=16) had primary liver malignancies while the remainder had metastatic disease. Liver resection included right hepatectomy or trisegmentectomy, left or extended left hepatectomy, and sectorectomy/segmentectomy in 77% (n=20), 8% (n=2), and 15% (n=4) of patients, respectively. The mean length of stay was 8.3 days (range, 3–33 days) and there were no grade IV morbidities or 90-day mortalities. The incidence of post hepatectomy liver failure (PHLF) was 3.8% (n=1). The median time to progression after resection was 4.5 months (range, 3.3–10 months). Twenty-three percent (n=6) of patients had no recurrence. The median survival was 28.9 months (range, 16.9–46.8 months) from major hepatectomy and 37.6 months (range, 25.2–53.1 months) from TARE.ConclusionsMajor hepatectomy after neoadjuvant lobar radioembolization is safe with a low incidence of PHLF.  相似文献   
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Conventional biochemical characterization and an ELISA technique were compared for their ability to identify reference cultures and fresh isolates from suppurating and non-suppurating periodontal pockets, as well as healthy gingival sulci in the same individual. Antisera to Bacteroides gingivalis strain 381, Bacteroides intermedius strains 581 and VP1 8944, and Bacteroides melaninogenicus ss. melaninogenicus strain 287 were prepared by immunizing rabbits. The antisera were conjugated with peroxidase and appropriate dilutions were chosen to minimize cross-reactions in the ELISA technique. Conventional characterization of the isolates included cellular and colonial morphology, biochemical characterization, and gas liquid chromatography of acid end products. The antisera appeared to be specific for each black-pigmented species, since cross-reactions were not observed to reference strains of heterologous species. There was a 94% agreement between the ELISA and conventional identifications of over 300 fresh isolates from periodontal sites.
The predominant black-pigmented Bacteroides species isolated from suppurating sites was Bacteroides intermedius using either identification technique. The median value of proportions of this species was significantly increased in the suppurating periodontal pockets (16.5%) when compared to non-suppurating deep periodontal pockets (3%) and healthy gingival sulci (0%). Significant differences in proportions were not observed for the other species of black-pigmented Bacteroides .  相似文献   
8.
The holographic facial profile scan is a new technique for creation of high-resolution, three-dimensional, realistic facial computer models which can be used for surgical planning and documentation in maxillofacial surgery. First, a holographic image of the patient is recorded using a pulsed laser system. In a second step, called holographic tomography, the real image of the patient's hologram is reconstructed by means of a continuous-wave laser. By moving a screen through the real three-dimensional image, it is sliced into a series of two-dimensional projections which are captured with a digital camera. The slices containing the specific two-dimensional information are superimposed to a three-dimensional surface model using special software. The extremely short exposure time of 35 nanoseconds for taking a holographic image is separated from the time-consuming rendering process of the surface model; thus, the obtained models are not affected by the movements of the patient.  相似文献   
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Recently, data have become available pertaining both to the estimated somatic hazard from exposure of populations to low doses of ionizing radiation and to the extent of exposure resulting from dental radiography. This has made possible an estimation of the somatic hazard to the United States population from dental radiography. It is concluded that the greatest risk of lethality would result from induction of leukemia, but that the actual hazard is probably quite low. It is advised that all procedures which will reduce the radiation exposure to the patient consistent with diagnostic requirements should be employed in order to minimize the potential risk.  相似文献   
10.
Bilateral prophylactic mastectomies (BPM) in young previvors with high‐risk mutations are rising; however, little data on management, therapy timing, and outcomes exist. BRCA+ patients under 30 undergoing BPM from 2006 to 2018 were reviewed. Twenty‐two patients aged 23‐29 underwent mastectomy 4.2 years after genetic diagnosis. Twelve patients completed surveys, most often citing personal decisions (50%) for undergoing mastectomy and plastic surgeons’ recommendations (83.3%) for reconstruction. About 73% of patients completely understood risks/benefits of mastectomy and 63.6% of reconstruction. Patients reported high BREAST‐Q Satisfaction and Well‐Being scores. Continued educational resource development will optimize shared decision‐making in the reconstructive process.  相似文献   
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