165 resultados para Turmells--Ferides i lesions
em University of Queensland eSpace - Australia
Resumo:
A 47 year old man undergoing immunotherapy for metastatic melanoma with autologous dendritic cells pulsed with autologous tumour peptide and hepatitis a surface antigen developed acute left ankle arthritis. Gout and acute infection were excluded, and an autoimmune aetiology or occult metastasis were considered. The arthritis initially subsided with indomethacin, but the symptoms recurred 2 months later, and magnetic resonance imaging demonstrated metastatic melanoma of the left talus. Immunohistochemical staining of a cerebral metastatic deposit biopsied 1 week after the onset of arthritis demonstrated T-cell and macrophage infiltration of the tumour. In addition, the patient developed melanoma-specific delayed type hypersensitivity and cytotoxic T-cell responses after vaccination. Thus, the monoarthritis represented an 'appropriate' inflammatory response directed against metastatic melanoma. (C) 2001 Lippincott Williams & Wilkins.
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A retrospective review of ultrasound guided breast excisional biopsies performed in a Surgical Unit of Princess Alexandra Hospital in 1998-99 was undertaken to assess the use of ultrasound specimen radiography. In this series a total of 55 localization biopsies were performed for impalpable lesions in 53 women. In 21 patients (38%), specimen ultrasound was used to confirm that the lesion in question had been excised, whereas for 34 lesions (62%), specimen X-ray was undertaken. In a total of six cases (10.9% overall) the radiographic abnormality was seen on ultrasound only. Real-time specimen sonography is a technique which is very appropriately utilized in conjunction with ultrasound guided excisions and can be easily performed either in the radiology department or the operative suite With minimal time delay. It could have particular application for lesions that are detected in younger women with dense breast parenchyma. The results of this review confirm specimen sonography to be a reliable technique. (C) 2002 Elsevier Science Ltd. All rights reserved.
Resumo:
Columnar cell lesions (CCLs) of the breast are a spectrum of lesions that have posed difficulties to pathologists for many years, prompting discussion concerning their biologic and clinical significance. We present a study of CCL in context with hyperplasia of usual type (HUT) and the more advanced lesions ductal carcinoma in situ (DCIS) and invasive ductal carcinoma. A total of 81 lesions from 18 patients were subjected to a comprehensive morphologic review based upon a modified version of Schnitt's classification system for CCL, immunophenotypic analysis (estrogen receptor [ER], progesterone receptor [PgR], Her2/neu, cytokeratin 5/6 [CK5/6], cytokeratin 14 [CK14], E-cadherin, p53) and for the first time, a whole genome molecular analysis by comparative genomic hybridization. Multiple CCLs from 3 patients were studied in particular detail, with topographic information and/or showing a morphologic spectrum of CCL within individual terminal duct lobular units. CCLs were ER an PgR positive, CK5/6 and CK14 negative, exhibit low numbers of genetic alterations and recurrent 16q loss, features that are similar to those of low grade in situ and invasive carcinoma. The molecular genetic profiles closely reflect the degree of proliferation and atypia in CCL, indicating some of these lesions represent both a morphologic and molecular continuum. In addition, overlapping chromosomal alterations between CCL and more advanced lesions within individual terminal duct lobular units suggest a commonality in molecular evolution. These data further support the hypothesis that CCLs are a nonobligate, intermediary step in the development of some forms of low grade in situ and invasive carcinoma. Copyright: © 2005 Lippincott Williams & Wilkins, Inc.
Resumo:
Nine individuals with complex language deficits following left-hemisphere cortical lesions and a matched control group (n 5 9) performed speeded lexical decisions on the third word of auditory word triplets containing a lexical ambiguity. The critical conditions were concordant (e.g., coin–bank–money), discordant (e.g., river–bank–money), neutral (e.g., day–bank– money), and unrelated (e.g., river–day–money). Triplets were presented with an interstimulus interval (ISI) of 100 and 1250 ms. Overall, the left-hemisphere-damaged subjects appeared able to exhaustively access meanings for lexical ambiguities rapidly, but were unable to reduce the level of activation for contextually inappropriate meanings at both short and long ISIs, unlike control subjects. These findings are consistent with a disruption of the proposed role of the left hemisphere in selecting and suppressing meanings via contextual integration and a sparing of the right-hemisphere mechanisms responsible for maintaining alternative meanings.
Resumo:
An on-line priming experiment was used to investigate discourse-level processing in four matched groups of subjects: individuals with nonthalamic subcortical lesions (NSL) ( n =10), normal control subjects ( n =10), subjects with Parkinsons disease (PD) ( n =10), and subjects with cortical lesions ( n =10). Subjects listened to paragraphs that ended in lexical ambiguities, and then made speeded lexical decisions on visual letter strings that were: nonwords, matched control words, contextually appropriate associates of the lexical ambiguity, contextually inappropriate associates of the ambiguity, and inferences (representing information which could be drawn from the paragraphs but was not explicitly stated). Targets were presented at an interstimulus interval (ISI) of 0 or 1000ms. NSL and PD subjects demonstrated priming for appropriate and inappropriate associates at the short ISI, similar to control subjects and cortical lesion subjects, but were unable to demonstrate selective priming of the appropriate associate and inference words at the long ISI. These results imply intact automatic lexical processing and a breakdown in discourse-based meaning selection and inference development via attentional/strategic mechanisms.
Resumo:
We analyze the quantum dynamics of radiation propagating in a single-mode optical fiber with dispersion, nonlinearity, and Raman coupling to thermal phonons. We start from a fundamental Hamiltonian that includes the principal known nonlinear effects and quantum-noise sources, including linear gain and loss. Both Markovian and frequency-dependent, non-Markovian reservoirs are treated. This treatment allows quantum Langevin equations, which have a classical form except for additional quantum-noise terms, to be calculated. In practical calculations, it is more useful to transform to Wigner or 1P quasi-probability operator representations. These transformations result in stochastic equations that can be analyzed by use of perturbation theory or exact numerical techniques. The results have applications to fiber-optics communications, networking, and sensor technology.
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In this chapter we present a review of some of the main threads of research on the role played by emotion and affect in organizations. In this respect, we refute the notion that organizations are totally rational., where the role of emotion is something that can be discounted or 'managed' out of existence.
Resumo:
Brain electrical activity related to working memory was recorded at 15 scalp electrodes during a visuospatial delayed response task. Participants (N = 18) touched the remembered position of a target on a computer screen after either a 1 or 8 sec delay. These memory trials were compared to sensory trials in which the target remained present throughout the delay and response periods. Distracter stimuli identical to the target were briefly presented during the delay on 30% of trials. Responses were less accurate in memory than sensory trials, especially after the long delay. During the delay slow potentials developed that were significantly more negative in memory than sensory trials. The difference between memory and sensory trials was greater at anterior than posterior electrodes. On trials with distracters, the slow potentials generated by memory trials showed further enhancement of negativity whereas there were minimal effects on accuracy of performance. The results provide evidence that engagement of visuospatial working memory generates slow wave negativity with a timing and distribution consistent with frontal activation. Enhanced brain activity associated with working memory is required to maintain performance in the presence of distraction. © 1997 by the Massachusetts Institute of Technology
Resumo:
Evidence of infection with spirorchid flukes (Digenea: Spirorchidae) was sought at necropsy of 96 stranded green turtles, Chelonia mydas, that were examined during the course of a survey of marine turtle mortality in southeastern Queensland, Australia. Three species of spirorchid (Hapalotrema mehrai, H. postorchis, and Neospirorchis schistosomatoides) were identified. Severe disease due to spirorchid fluke infection (spirorchidiasis) was implicated as the principal cause of mortality in 10 turtles (10%), and appeared to be one of multiple severe problems in an additional 29 turtles (30%). Although flukes were observed in only 45% of stranded C. mydas in this study, presumed spirorchid fluke infection was diagnosed in an additional 53% of turtles, based principally on characteristic necropsy lesions and to a lesser extent on the histopathological detection of spirorchid eggs. Characteristic necropsy lesions included miliary spirorchid egg granulomas, which were observed most readily on serosal surfaces, particularly of the small intestine. Cardiovascular lesions included mural endocarditis, arteritis, and thrombosis, frequently accompanied by aneurysm formation. Resolution of thrombi was observed to occur via a combination of granuloma formation about indigestible components (spirorchid fluke egg shells) and exteriorization through the vessel wall, which resulted in granulomatous nodules on the adventitial surface. Septic aortic thrombosis complicated by disseminated bacterial infection, observed in five turtles, was recorded for the first time. Egg granulomas were ubiquitous in turtle tissues throughout this study. Although they generally appeared to be mild or incidental lesions, they were occasionally associated with severe multifocal granulomatous pneumonia or meningitis.
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To evaluate an antigen delivery system in which exogenous antigen can target the major histocompatibility complex (MHC) class I pathway, a single human papillomavirus (HPV) 16 E7 cytotoxic T lymphocyte (CTL) epitope and a single HIV gp160 CTL epitope were separately fused to the C-terminus or bovine papillomavirus 1 (BPV1) L1 sequence to form hybrid BPV1L1 VLPs. Mice immunized with these hybrid VLPs mounted strong CTL responses against the relevant target cells in the absence of any adjuvants. In addition, the CTL responses induced by immunization with BPV1L1/HPV16E7CTL VLPs protected mice against challenge with E7-transformed tumor cells. Furthermore, a high titer-specific antibody response against BPV1L1 VLPs was also induced, and this antiserum could inhibit papillomavirus-induced agglutination of mouse erythrocytes, suggesting that the antibody may recognize conformational determinates relevant to virus neutralization. These data demonstrate that hybrid BPV1L1 VLPs can be used as carriers to target antigenic epitopes to both the MHC class I and class II pathways, providing a promising strategy for the design of vaccines to prevent virus infection, with the potential to elicit therapeutic virus-specific CTL responses. (C) 1998 Academic Press.
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This is the first in a series of three articles which aimed to derive the matrix elements of the U(2n) generators in a multishell spin-orbit basis. This is a basis appropriate to many-electron systems which have a natural partitioning of the orbital space and where also spin-dependent terms are included in the Hamiltonian. The method is based on a new spin-dependent unitary group approach to the many-electron correlation problem due to Gould and Paldus [M. D. Gould and J. Paldus, J. Chem. Phys. 92, 7394, (1990)]. In this approach, the matrix elements of the U(2n) generators in the U(n) x U(2)-adapted electronic Gelfand basis are determined by the matrix elements of a single Ll(n) adjoint tensor operator called the del-operator, denoted by Delta(j)(i) (1 less than or equal to i, j less than or equal to n). Delta or del is a polynomial of degree two in the U(n) matrix E = [E-j(i)]. The approach of Gould and Paldus is based on the transformation properties of the U(2n) generators as an adjoint tensor operator of U(n) x U(2) and application of the Wigner-Eckart theorem. Hence, to generalize this approach, we need to obtain formulas for the complete set of adjoint coupling coefficients for the two-shell composite Gelfand-Paldus basis. The nonzero shift coefficients are uniquely determined and may he evaluated by the methods of Gould et al. [see the above reference]. In this article, we define zero-shift adjoint coupling coefficients for the two-shell composite Gelfand-Paldus basis which are appropriate to the many-electron problem. By definition, these are proportional to the corresponding two-shell del-operator matrix elements, and it is shown that the Racah factorization lemma applies. Formulas for these coefficients are then obtained by application of the Racah factorization lemma. The zero-shift adjoint reduced Wigner coefficients required for this procedure are evaluated first. All these coefficients are needed later for the multishell case, which leads directly to the two-shell del-operator matrix elements. Finally, we discuss an application to charge and spin densities in a two-shell molecular system. (C) 1998 John Wiley & Sons.