956 resultados para Fast Field Cycling NMR
Disengaging leadership: Educational administration and management as a field of scientific knowledge
Resumo:
This study was aimed at assessing the psychometric qualities of the fast alcohol screening test (FAST), and at comparing these qualities to those of the alcohol use disorders identification test (AUDIT) in three samples of Brazilian adults: (i) subjects attended at an emergency department (530); (ii) patients from a psychosocial care center (40); and (iii) university students (429). The structured clinical interview for diagnosis (SCID)-IV was used as gold standard. The FAST demonstrated high test-retest and interrater reliability coefficients, as well as high predictive and concurrent validity values. The results attest the validity and reliability of the Brazilian version of the FAST for the screening of indicators of alcohol abuse and dependence.
Resumo:
Magnetic resonance (MR) imaging is the most important imaging modality for the evaluation of traumatic or degenerative cartilaginous lesions in the knee. It is a powerful noninvasive tool for detecting such lesions and monitoring the effects of pharmacologic and surgical therapy. The specific MR imaging techniques used for these purposes can be divided into two broad categories according to their usefulness for morphologic or compositional evaluation. To assess the structure of knee cartilage, standard spin-echo (SE) and gradient-recalled echo (GRE) sequences, fast SE sequences, and three-dimensional SE and GRE sequences are available. These techniques allow the detection of morphologic defects in the articular cartilage of the knee and are commonly used in research for semiquantitative and quantitative assessments of cartilage. To evaluate the collagen network and proteoglycan content in the knee cartilage matrix, compositional assessment techniques such as T2 mapping, delayed gadolinium-enhanced MR imaging of cartilage (or dGEMRIC), T1 rho imaging, sodium imaging, and diffusion-weighted imaging are available. These techniques may be used in various combinations and at various magnetic field strengths in clinical and research settings to improve the characterization of changes in cartilage. (C)RSNA, 2011 , radiographics.rsna.org
Resumo:
One hundred and fifty-one Erysipelothrix spp. isolates from diseased and carrier swine from Brazil were identified by PCR, submitted to serotyping and analyzed by amplified fragment length polymorphism with a single enzyme (AFLP). Reference strains from Australia and the United Kingdom were also examined. The 151 strains were classified into 18 different serotypes (1a, 1b, 2a, 2b, 4, 5, 6, 7, 8, 10, 11, 12, 15, 17, 19, 21, 24 and 25), being serotype 2b the most frequent (39.7%). By associating serotyping and PCR results, it was possible to identify 146 strains as E. rhusiopathiae and five strains as E. tonsillarum. Despite the fact that for this genus AFLP did not cluster all isolates according to serotype, origin, disease or isolation data, the execution of the technique was easy and fast, demonstrating high discriminatory power. The results produced by the AFLP analysis of Erysipelothrix spp. could also support its use as a discriminatory tool for E. rhusiopathiae and E. tonsillarum species. (C) 2010 Elsevier B.V. All rights reserved.
Resumo:
At the end of 2002 and throughout 2003, there was a severe outbreak of infectious laryngotracheitis (ILT) in an intensive production area of commercial hens in the Sao Paulo State of Brazil. ILT virus was isolated from 28 flocks, and 21 isolates were genotyped by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) using four genes and eight restriction enzymes, and by partial sequencing of the infected cell protein 4 (ICP4) and thymidine kinase (TK) genes. Three groups resulted from the combinations of PCR-RFLP patterns: 19 field isolates formed Group I, and the remaining two isolates together with the chicken embryo origin (CEO) vaccine strains formed Group II. Group III comprised the tissue-culture origin (TCO) vaccine strain by itself. The PCR-RFLP results agreed with the sequencing results of two ICP4 gene fragments. The ICP4 gene sequence analysis showed that the 19 field isolates classified into Group I by RFLP-PCR were identical among themselves, but were different to the TCO and CEO vaccines. The two Group II isolates could not be distinguished from one of the CEO vaccines. The nucleotide and amino acid sequence analyses discriminated between the Brazilian and non-Brazilian isolates, as well as between the TCO and CEO vaccines. Sequence analysis of the TK gene enabled classification of the field isolates (Group I) as virulent and non-vaccine. This work shows that the severe ILT outbreak was caused by a highly virulent, non-vaccine strain.
Resumo:
Two different regions of the infected cell protein 4 (ICP4) gene of infectious laryngotracheitis virus (ILTV) were amplified and sequenced for characterization of field isolates and tissue culture-origin (TCO) and chicken embryo-origin (CEO) vaccine strains. Phylogenetic analysis of the two regions showed differences in nucleotide and amino acid sequences between field isolates and attenuated vaccines. The PCR-RFLP results were identical to those obtained by DNA sequencing and validated their use to differentiate ILTV strains. The approach using the sequencing of the two fragments of the ICP4 gene showed to be an efficient and practical procedure to differentiate between field isolates and vaccine strains of ILTV. (C) 2009 Elsevier Ltd. All rights reserved.