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排序方式: 共有622条查询结果,搜索用时 15 毫秒
1.
Maria Gonzalez-Cao Cristina Carrera Juan Francisco Rodriguez Moreno Pedro Rodríguez-Jiménez Mónica Antoñanzas Basa Rosa Feltes Ochoa Teresa Puertolas Eva Muñoz-Couselo José Luis Manzano Ivan Marquez-Rodas Juan Martín-Liberal Ainara Soria Pilar Lopez Criado Almudena Garcia-Castaño Aram Boada Pablo Ayala de Miguel Susana Puig Guillermo Crespo Alfonso Berrocal 《Journal of the American Academy of Dermatology》2021,84(5):1412-1415
2.
S Amartur Z P Liang F Boada E M Haacke 《Journal of magnetic resonance imaging : JMRI》1991,1(6):721-724
The authors present an improvement to a sigma-filter extrapolation method for the reconstruction of magnetic resonance (MR) images from symmetric discrete Fourier data. By making use of the phase information in the image data, the proposed method can overcome the data inconsistency problem of the original method for handling MR image data with large phase variations, such as those obtained in gradient-echo pulse sequences. Reconstruction results show that its performance is comparable with that of the modified complex sigma-filter method proposed previously to handle the inconsistency problem. However, the new approach has the advantage of reducing computation time by a factor of two with use of a sigma filter applied to real instead of complex images. It is expected that this method will be more practical for use in clinical MR imaging systems. 相似文献
3.
Diaz D Prieto A Barcenilla H Monserrat J Prieto P Sánchez MA Reyes E Hernandez-Fuentes MP de la Hera A Orfao A Alvarez-Mon M 《Journal of leukocyte biology》2004,76(3):609-615
The analysis of apoptosis in cell populations involves the detection of their specific lineage antigen (LAg) expression. This experimental approach relies on their assumed constant expression, but it is unclear whether such expression is actually maintained during cell death. We examined whether the loss of LAgs is a common feature of apoptotic lymphocytes and whether some might completely lose their LAgs. The changes in the expression of CD3, CD5, CD8, CD4, CD28, CD56, and CD19 were monitored in highly purified lymphocyte populations obtained by negative selection in a fluorescence-activated cell sorter. These were cultured for 24 h with or without phytohemagglutinin or staurosporin. For each LAg-positive subset studied, apoptosis was consistently more common among cells showing partial or total loss of LAg expression compared with cells maintaining their initial LAg levels. The kinetics of expression loss was rapid for CD8, CD56, and CD28, and more than 80% of initial expression was lost in the early stages of apoptosis but was slower for CD3, CD5, and CD4. For CD3 and CD5, expression was dependent on the apoptotic stimulus used. It is interesting that loss of antigen expression was independent of cell size. This phenomenon was also found in nonmanipulated, highly pure CD19 B lymphocytes of peripheral blood mononuclear cells from B chronic lymphocytic leukemia patients. Loss of LAg expression appeared to be a common feature of apoptotic lymphocytes under all the conditions assayed. The different kinetic patterns of LAg loss suggest apoptotic cells might actively regulate this process. 相似文献
4.
5.
Mutations in APP are associated with familial early-onset Alzheimer disease (FAD). Examination of the genomic sequence in one patient with FAD revealed a change located in the axon 17 of the APP gene at position 275329G>A (GenBank accession number: D87675; GI: 2429080); cDNA sequence 2137G>A (GenBank accession number: X06989; GI: 28720). This corresponds to the mutation A713T in APP. AD stage VI of neurofibrillary degeneration and stage C of Aβ-amyloid burden was found at the post-mortem neuropathological examination. Previous studies have suggested that the mutation A713T in APP is a silent mutation or polymorphism. However, we have not found this change in APP in a control population analyzed by the amplification-refractory mutation system (ARMS). It is concluded that A713T in APP is implicated in the pathogenesis of AD. Since the immunohistochemical study indicates that A713T mutation is not likely to relate with Aβ-amyloid processing, the causative role of this rare mutation remains to be warranted. 相似文献
6.
Jennifer Janusz Caroline Harrison Cristina Boada Lisa Cordeiro Susan Howell Nicole Tartaglia Richard Boada 《American journal of medical genetics. Part C, Seminars in medical genetics》2020,184(2):469-481
Few studies have systematically assessed executive functioning (EF) skills in boys with XXY, and these are limited by small samples and restricted EF assessment. This study used a broader battery of performance‐based measures as well as parent‐rating scales of EF in 77 boys and adolescents with XXY (mean age = 12.5 years), recruited from a clinical trial and an outpatient clinic. Exploratory factor analyses were used to create EF domains from performance‐based measures, and similar domains were measured using the Behavior Rating Inventory of Executive Function and Conners Parent‐Rating Scales. The boys with XXY showed a distinct EF profile, with the greatest deficit in attention and more moderate deficits in working memory, switching, and planning/problem solving. Parent ratings showed similar challenges, as well as impaired inhibition. Independent sample t‐tests showed no difference on performance measures between boys diagnosed or not diagnosed with attention‐deficit/hyperactivity disorder (ADHD), although parents of boys diagnosed with ADHD reported more difficulties. There were no differences on performance‐based tests between those diagnosed pre‐ and postnatally, although parents of postnatally diagnosed boys reported more metacognitive problems. Language deficits, cognition, and socio‐economic status did not account for EF deficits. 相似文献
7.
Helmut Schrder Vanessa Cruz Muoz Marta Urquizu Rovira Victoria Valls Ibaez Josep-Maria Manresa Domínguez Gerard Ruiz Blanco Monserrat Urquizu Rovira Pere Toran Monserrat 《Nutrients》2021,13(6)
Increasing sugar-sweetened beverages (SSB) consumption and associated health impacts warrant health-policy action. We assessed associations of socioeconomic and lifestyle variables with adolescents’ consumption of regular soda (RSD), sport (SD), and energy (ED) drinks. Cross-sectional study of 3930 Spanish adolescents (2089 girls, 1841 boys) aged 13–18 years). We compared frequency of consuming each SSB type (European Food Safety Authority questionnaire) with sociodemographic and lifestyle variables (standardized questions). RSD, SD, and ED were consumed at least weekly by 72.7%, 32.3%, and 12.3% of participants, respectively, and more frequently (p < 0.001) by boys, compared to girls. Multivariate ordinal logistic regression showed inverse association between RSD, SD, and ED consumption and parental occupation-based socioeconomic status (p < 0.01). Daily smoking was associated (p < 0.001) with higher ED (OR 3.64, 95% CI 2.39–5.55) and RSD (OR 2.15, 95% CI 1.56–2.97) consumptions. SD intake was associated inversely with smoking (OR 0.60, 95% CI 0.40–0.89, p = 0.012) and directly with physical activity (OR 2.93, 95% CI 2.18–3.95, p < 0.001). School performance was lower among ED (OR 2.14, 95% CI, 1.37–3.35, p = 0.001) and RSD (OR 1.81, 95% CI 1.24–2.64, p = 0.002) consumers, compared to SD. Maleness and low socioeconomic status predicted SSB consumption. Smoking and low school performance were associated with higher ED and RSD intakes. 相似文献
8.
Añez Simón C Boada Pié S Solsona Dellá B 《Revista espa?ola de anestesiología y reanimación》2000,47(8):352-362
The laryngeal mask for intubation (MLI), or "Fastrach", is a new device designed by Brain for airway management. The MLI, a modified version of the conventional laryngeal mask, allows for blind intubation through the device using endotracheal tubes up to 8 mm in diameter. Insertion with the head in a neutral position makes this system useful for managing the airway when neck injury is present. The device has been used successfully in patients assessed as having difficult-to-manage airways and its use in emergencies inside or outside the hospital is promising. The MLI has been used with high rates of success in combination with other techniques such as fiberoptic bronchoscopy (success rate 99 to 100%) and transillumination (95 to 100% success rate) in patients whose airways have been considered difficult to manage. Given such high rates of success for MLI placement (95 to 100%) and for blind orotracheal intubation (81 to 100%), the Fastrach may offer an alternative to the conventional laryngeal mask in algorithms for airway management. 相似文献
9.