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991.
A.C. da Costa I. Bendit A.C.S. de Oliveira E.G. Kallas E.C. Sabino S.S. Sanabani 《Clinical microbiology and infection》2013,19(1):E31-E43
Human parvovirus B19V (B19V) has been associated with various haematological disorders, but data on its prevalence in leukaemia are scarce. In this cross-sectional study, we investigated patients in Sao Paulo, Brazil with leukaemia to determine the molecular frequency of B19 variants and characterize the viral genetic variability by partial and complete sequencing of the coding of non-structural protein 1 (NS1)/viral capsid proteins 1 and 2 (VP1/VP2). The presence of B19V infections was investigated by PCR amplification of the viral NS1 gene fragment and confirmed by sequencing analysis. The NS1/VP1/VP2 and partially larger gene fragments of the NS1-positive samples were determined by overlapping nested PCR and direct sequencing results. The B19V NS1 was detected in 40 (16%) of 249 bone marrow samples including 12/78 (15.4%) acute lymphoblastic leukaemia, 25/155 (16.1%) acute myeloid leukaemia and 3/16 (18.7%) chronic myeloid leukaemia samples. Of the 40 participants, 25 (62.5%) were infected with genotype 1a and 15 (37.5%) with genotype 3b. The phylogenetic analysis of other regions revealed that 12/40 (30%) of the patients with leukaemia were co-infected with genotypes 1a and 3b. In addition, a new B19V intergenotypic recombinant (1a/3b) and an NS1 non-recombinant genotype 1a were detected in one patient. Our findings demonstrated a relatively high prevalence of B19V monoinfections and dual infections and provide, for the first time, evidence of inter-genotypic recombination in adults with leukaemia that may contribute to the genetic diversity of B19V and may also be a source of new emerging viral strains with future implications for diagnosis, therapy and efficient vaccine development. 相似文献
992.
Marcos Forte Wanderley L. de Souza Roseli F. da Silva Antonio F. do Prado Jose F. Rodrigues 《International journal of medical informatics》2013,82(11):1111-1122
BackgroundIn nurse and in medicine courses, the use of reflective portfolios as a pedagogical tool is becoming a common practice; in the last years, this practice has gradually migrated from paper-based to electronic-based portfolios. Current approaches for reflective e-portfolios, however, do not widely operate at outdoor sites, where data networks are limited or nonexistent. Considering that many of the activities related to nurse and medicine courses relate to professional practices conducted in such conditions, these network shortcomings restrict the adoption of e-portfolios.PurposeThe present study describes the requirements specification, design, implementation, and evaluation of the Ubiquitous Reflective E-Portfolio Architecture, a solution proposed to support the development of systems based on mobile and wired access for both online and offline operation.MethodsWe have implemented a prototype named Professional Practice Module to evaluate the Ubiquitous Reflective E-Portfolio Architecture; the module was based on requirements observed during the professional practice, the paper-based portfolio in use, and related learning meetings in the Medicine Course of a Brazilian University. The evaluation of the system was carried out with a learning group of 2nd year students of the medicine course, who answered to extensive evaluation questionnaires.ResultsThe prototype proved to be operational in the activities of the professional practice of the Medicine Course object of the study, including homework tasks, patient care, data sharing, and learning meetings. It also demonstrated to be versatile with respect to the availability of the computer network that, many times, was not accessible. Moreover, the students considered the module useful and easy to use, but pointed out difficulties about the keyboard and the display sizes of the netbook devices, and about their operational system. Lastly, most of the students declared preference for the electronic Professional Practice Module in internal and in group activities, and for the paper-based version while in patient attendance.ConclusionsThere is evidence that the environment where the professional practice takes place influences the usage of the e-portfolio. Mobile devices were able to support students in their professional practice; however, these devices present characteristics that must be judiciously selected, otherwise, they may limit the execution of important tasks. The main shortcoming identified during the evaluation tests was about the use of the module, and of the access device, during patient attendance. For this reason, we have envisioned a new version of the Professional Practice Module that shall follow a twofold requisite: by one side, it will include all the features of the module, to be used at the university or in the students’ homes; from the other side, it will include only the features that are essential for the practice of patient attendance. 相似文献
993.
994.
João R. Silva António Ascensão Franklim Marques André Seabra António Rebelo José Magalhães 《European journal of applied physiology》2013,113(9):2193-2201
The main aim was to analyse the impact of an official match on hormonal and redox status, muscle damage and inflammation and neuromuscular function. Seven high-level male soccer players from the same team performed an official match and data were collected 72 h before, 24, 48 and 72 h post-match. Plasma testosterone/cortisol ratio (T/C), creatine kinase (CK), superoxide dismutase (SOD), glutathione peroxidase (GPX) and reductase (GR) activities, myoglobin (Mb), C-reactive protein (CRP), uric acid (UA), protein sulfhydryls (–SH), malondialdehyde (MDA) concentrations and total antioxidant status (TAS) were measured. Sprint, jump and change of direction performance, and maximal isokinetic knee extension and flexion were obtained as neuromuscular functional parameters. Cortisol increased and T/C decreased until 48 h recovery (P < 0.05). Mb, CRP and –SH (P < 0.05) increased at 24 h and CK, TAS, SOD and MDA (P < 0.05) increased up to 48 h recovery. GR increased and GPX decreased at 24 h recovery (P < 0.05). Jump performance decreased 24 h post-match (P < 0.05), but no significant alterations in sprint, change of direction and muscle strength were observed. In conclusion, an official match resulted in changes in plasma biomarkers until 48 h of recovery period, without major impact on performance. 相似文献
995.
996.
Felipe Lipsky Luis Henrique da Silveira Lacerda Srgio Ricardo de Lazaro Elson Longo Juan Andrs Miguel Angel San-Miguel 《RSC advances》2020,10(51):30640
Over the years, the possibility of using solar radiation in photocatalysis or photodegradation processes has attracted remarkable interest from scientists around the world. In such processes, due to its electronic properties, Ag3PO4 is one of the most important semiconductors. This work delves into the photocatalytic activity, stability, and reactivity of Ag3PO4 surfaces by comparing plane waves with projector augmented wave and localized Gaussian basis set simulations, at the atomic level. The results indicate that the (110) surface, in agreement with previous experimental reports, displays the most suitable characteristics for photocatalytic activity due to its high reactivity, i.e. the presence of a large amount of undercoordinated Ag cations and a high value work function. Beyond the innovative results, this work shows a good synergy between both kinds of DFT approaches.Over the years, the possibility of using solar radiation in photocatalysis or photodegradation processes has attracted remarkable interest from scientists around the world. 相似文献
997.
Breno Bittencourt de Brito Fabian Fellipe Bueno Lemos Caroline da Mota Carneiro ressa Santos Viana Nilo Manoel Pereira Vieira Barreto Gabriela Alves de Souza Assis Barbara Dicarlo Costa Braga Maria Lu sa Cordeiro Santos Filipe Ant nio Fran a da Silva Hanna Santos Marques Nat lia Oliveira e Silva Fabr cio Freire de Melo 《World Journal of Meta-Analysis》2021,9(3):257-276
Gastric adenocarcinoma is a global health concern, and Helicobacter pylori (H. pylori) infection is the main risk factor for its occurrence. Of note, the immune response against the pathogen seems to be a determining factor for gastric oncogenesis, and increasing evidence have emphasized several host and bacterium factors that probably influence in this setting. The development of an inflammatory process against H. pylori involves a wide range of mechanisms such as the activation of pattern recognition receptors and intracellular pathways resulting in the production of proinflammatory cytokines by gastric epithelial cells. This process culminates in the establishment of distinct immune response profiles that result from the cytokine-induced differentiation of T naïve cells into specific T helper cells. Cytokines released from each type of T helper cell orchestrate the immune system and interfere in the development of gastric cancer in idiosyncratic ways. Moreover, variants in genes such as single nucleotide polymorphisms have been associated with variable predispositions for the occurrence of gastric malignancy because they influence both the intensity of gene expression and the affinity of the resultant molecule with its receptor. In addition, various repercussions related to some H. pylori virulence factors seem to substantially influence the host immune response against the infection, and many of them have been associated with gastric tumorigenesis. 相似文献
998.
Anthony DAmico Kevin Silva Joseph Gallo 《International Journal of Sports Physical Therapy》2021,16(2):431
BackgroundWith the increased popularity of foam rolling (FR), it is important to establish the exact manner in which the practice is useful.PurposeThe purpose of this study was to examine the impact of FR the iliotibial (IT) band on hip adduction range of motion (ROM) and the short-term time course of any ROM changes that may occur.MethodIn a within-subject design, 34 subjects (21 female, 13 male) (female mean age 24.67 ± 8.6 yrs, height 161.4 ± 9.8 cm, mass 67.3 ± 12.3 kg; male mean age 22 ± 2.5 yrs, height 170.2 ± 8.2 cm, mass 76.3 ± 21.9 kg) underwent a baseline Ober’s test to measure hip adduction ROM prior to the FR and control conditions. Subjects rolled the lateral portion of each thigh for 3 bouts of 20 seconds. A tempo of 3 seconds down and 3 seconds up the leg was maintained across FR bouts. A 5-minute walk served as the control condition. The Ober’s test was repeated at less than 1 minute, 3 minutes, 10 minutes, 15 minutes, and 20 minutes following the FR bouts and the control to assess changes in hip adduction ROM over time. A blinded clinician conducted the Ober’s test. A two-way analysis of variance was used to assess differences by condition and time.ResultsNo differences in hip adduction ROM were found at baseline between FR and CON within subjects (27.9 cm ± 7.5 vs. 27.7 cm ± 6.6, p > .05). Ober’s test ROM was significantly greater in FR compared to CON immediately post-treatment (24.2 cm ± 6.3 vs. 28.2 cm ± 6.3, p = .00, d = .59), and 3 minutes post (24.6 cm ± 7.6 vs. 28.3 cm ± 5.9, p = .00, d = .56). No differences were observed 10 minutes post, 15 minutes post, or 20 minutes post FR or CON (p > .05).DiscussionCompared to walking, FR the IT band significantly increased hip adduction ROM as measured by the Ober’s test. These increases appear to dissipate between 3 and 10 minutes post-FR.ConclusionAn acute bout of 3 sets of 20 seconds of FR may be effective for transiently increasing ROM. Whether these short-term increases have implications for chronic flexibility changes is unclear.Level of evidence2 相似文献
999.
Silvia A.S. Vedovello Ana Letícia Mello de Carvalho Larissa C. de Azevedo Patrícia R. dos Santos Mario Vedovello-Filho Marcelo de C. Meneghim 《The Angle orthodontist》2020,90(4):564
ObjectivesTo evaluate the impact of anterior occlusal conditions in the mixed dentition on item-level analysis of oral health–related quality of life (OHRQoL).Materials and MethodsA population-based cross-sectional study of 787 children aged 8 to 10 years was conducted. The Child Perceptions Questionnaire (CPQ8-10) was used to evaluate OHRQoL, and the analysis of item levels was performed on CPQ8-10 domains. Anterior occlusal characteristics were diagnosed according to the Dental Aesthetic Index criteria. Individual analyses were performed relating the outcome as independent variables. The variables with P < .20 in the individual analyses were tested in multiple logistic regression models, and those with P < .10 remained in the model. The adjusted odds ratio (OR) was estimated with a 95% confidence interval (CI).ResultsNo associations were found with regard to anterior occlusal characteristics (P < .001) after the variables of the previous determinants were adjusted for multivariate analysis. However, the following variables were significantly associated with negative impact on OHRQoL item levels: sex, in oral symptoms (OR = 1.42; CI, 1.07–1.89) and emotional well-being (OR = 1.34; CI, 1.00–1.79); race, in oral symptoms (OR = 1.48; CI, 1.10–1.98), emotional well-being (OR = 1.54; CI, 1.14–2.06), and social well-being (OR = 1.34; CI, 1.00–1.80); and family income in functional limitation (OR = 1.46; CI, 1.06–2.02), emotional well-being (OR = 1.71; CI, 1.21–2.42), and social well-being (OR = 1.59; CI, 1.14–2.21).ConclusionsAnterior occlusal conditions did not affect the levels of OHRQoL items. 相似文献
1000.