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121.
T-cell large granular lymphocytic leukaemia (T-LGLL) is a chronic clonal lymphoproliferative disorder of cytotoxic T lymphocytes which commonly occurs in older patients and is often associated with autoimmune diseases. Among 246 patients with T-LGLL seen at our institution over the last 10 years, we encountered 15 cases following solid organ or haematopoietic stem cell transplantation. Here, we studied the clinical characterization of these cases and compared them to de novo T-LGLL. This experience represented a clear picture of the intricate nature of the disease manifestation and the complexities of several immune mechanisms triggering the clonal expansion.  相似文献   
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Background

Studies report that in the UK, among men with severe mental illness (SMI), those of black Caribbean ethnicity display increased risk of aggressive behaviour, criminal convictions, and schizophrenia. The study aimed to compare aggressive behaviour and criminal convictions among men with SMI of white British, black Caribbean and black African ethnicity, and to explore factors associated with differences across ethnicities.

Method

Sample 1 included 1,104 male inpatients with SMI. Sample 2 included a representative sub-sample of 165 who completed interviews, and authorized access to medical and criminal files. Ethnicity was self-ascribed.

Results

Staff-rated violence prior to admission, self-reported aggressive behaviour, and convictions for non-violent and violent crimes differed among men with SMI of different ethnicities. Relative to men with SMI of white British ethnicity, those of black African ethnicity showed decreased risk of aggressive behaviour, and those of black Caribbean ethnicity showed elevated risk of convictions for non-violent, and marginally, for violent crimes. Relative to men with SMI of black African ethnicity, those of black Caribbean ethnicity showed elevated risk of aggressive behaviour and criminal convictions. Proportionately more of the men of both black African and black Caribbean ethnicity, than those of white British ethnicity, presented schizophrenia spectrum disorders. Multivariate analyses failed to identify factors that would explain differences in aggressive behaviour, and criminal convictions across ethnic groups.

Conclusions

Differences in four different measures of aggressive and antisocial behaviour among men with SMI of different ethnicities were observed but factors associated with these differences were not found.  相似文献   
124.
Introduction: In this study we examined oxidative stress and skeletal muscle damage resulting from acute strength, aerobic, or concurrent exercise in rats. Methods: The animals were divided into control (C), strength (SE), aerobic (AE), and combined (CE) exercise groups. They were euthanized at 3 different time‐points (6, 24, and 48 h) after acute exercise. Results: SE exercise rats had increased dichlorofluorescein oxidation at 6 h post‐exercise and decreased superoxide dismutase activity at all time‐points. Glutathione peroxidase activity and sulfhydryl levels were increased in the AE group at 48 h post‐exercise. Serum lactate dehydrogenase activity was increased in the SE and CE groups at 24 h and in the AE group at 48 h. Echo intensity was elevated at 24 h for all groups. Conclusions: Forty‐eight hours was sufficient for complete recovery from oxidative stress and muscle damage in the SE and CE groups, but not in the AE group. Muscle Nerve 50 : 79–86, 2014  相似文献   
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Background

Orthodontic palatal expansion appliances have been widely used with satisfactory and, most often, predictable clinical results. Recently, clinicians have successfully utilized micro-implants with palatal expander designs to work as anchors to the palate to achieve more efficient skeletal expansion and to decrease undesired dental effects. The purpose of the study was to use finite element method (FEM) to determine the stress distribution and displacement within the craniofacial complex when simulated conventional and micro-implant-assisted rapid palatal expansion (MARPE) expansion forces are applied to the maxilla. The simulated stress distribution produced within the palate and maxillary buttresses in addition to the displacement and rotation of the maxilla could then be analyzed to determine if micro-implants aid in skeletal expansion.

Methods

A three-dimensional (3D) mesh model of the cranium with associated maxillary sutures was developed using computed tomography (CT) images and Mimics modeling software. To compare transverse expansion stresses in rapid palatal expansion (RPE) and MARPE, expansion forces were distributed to differing points on the maxilla and evaluated with ANSYS simulation software.

Results

The stresses distributed from forces applied to the maxillary teeth are distributed mainly along the trajectories of the three maxillary buttresses. In comparison, the MARPE showed tension and compression directed to the palate, while showing less rotation, and tipping of the maxillary complex. In addition, the conventional hyrax displayed a rotation of the maxilla around the teeth as opposed to the midpalatal suture of the MARPE. This data suggests that the MARPE causes the maxilla to bend laterally, while preventing unwanted rotation of the complex.

Conclusions

In conclusion, the MARPE may be beneficial for hyperdivergent patients, or those that have already experienced closure of the midpalatal suture, who require palatal expansion and would worsen from buccal tipping of the teeth or maxillary complex.  相似文献   
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We propose that a cognitive map can be stored in the synapses between the pyramidal cells of CA3 in the form of the pattern of synaptic strenghths connecting them. The model requires only that there are place cells in CA3 and that the connections between them are modifiable in a Hebbian manner. Given these suppositions, the synaptic strengths must evolve to represent the distance between firing centers of synaptically connected place cells. We argue that this arrangement of synaptic weights embodies all the formal properties of a map. We demonstrate that the information stored in such a structure is sufficient to solve several classic spatial problems including finding shortest paths, and negotiating detours. It is clear that much of the physiology and anatomy necessary to more precisely characterize the model is not known at this time. Nevertheless the model is robust under a variety of cell and connection densities. It also performs well under several different functions relating distance to synaptic strength. What is most remarkable in the model is that it is a logical consequence of the several key anatomical and physiological properties of the CA3 region of rats. Whether this information is used by the rat is difficult to assess at this time. Regardless of the outcome of this question, the model has promising applications to the field of robot navigation. © 1997 Wiley-Liss, Inc.  相似文献   
130.
Lack of investment for magnetic resonance(MR)fusion systems is an obstacle to deliver targeted prostate biopsies within the prostate cancer diagnostic pathway.W...  相似文献   
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