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41.
Expression of T cell immunoglobulin- and mucin-domain-containing molecules-1 and -3 (TIM-1 and -3) in the rat nervous and immune systems 总被引:5,自引:0,他引:5
Gielen AW Lobell A Lidman O Khademi M Olsson T Piehl F 《Journal of neuroimmunology》2005,164(1-2):93-104
Expression of T cell immunoglobulin- and mucin-domain-containing molecules (TIMs) can be used as T helper (Th) differentiation markers in the human and mouse. We examined the expression of TIM-1 and -3 mRNAs in rat MBP(63-88)-induced experimental autoimmune encephalomyelitis (EAE). TIM-3 expression was upregulated in the spinal cord during EAE and following antigen restimulation of the encephalitogenic TCRBV8S2+ population. Interestingly, TIM-3 expression was also detected by in situ hybridization in resident cells of the nervous system. TIM-1 was expressed in B cells but not in resident CNS cells and TIM-1 mRNA levels in spinal cord were unchanged throughout the course of EAE. These results support the notion that TIM-3 can also be used as a Th1 differentiation marker in the rat. However, expression of TIM-1 and -3 is not restricted solely to T cells and the presence of TIM-3 in resident CNS cells may indicate a role for this molecule in the interaction between the nervous and immune systems. 相似文献
42.
Soft tissue aneurysmal bone cyst 总被引:4,自引:0,他引:4
A soft tissue aneurysmal bone cyst located in the right gluteus medius of a 21-year-old man is reported. On conventional radiography, the lesion demonstrated a spherically trabeculated mass with a calcific rim. On CT scan, it showed a well-organized peripheral calcification resembling a myositis ossificans. On MRI, it presented as a multilocular, cystic lesion with fluid-fluid levels. The lesion had no solid components except for intralesional septa. Although findings on imaging and histology were identical to those described in classical aneurysmal bone cyst, diagnosis was delayed because of lack of knowledge of this entity and its resemblance to the more familiar post-traumatic heterotopic ossification (myositis ossificans). 相似文献
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44.
We examined the role of gaze in a task where subjects had to reproduce the position of a remembered visual target with the tip of the index finger, referred to as pointing. Subjects were tested in 3 visual feedback conditions: complete darkness (dark), complete darkness with visual feedback of the finger position (finger), and with vision of a well-defined environment and feedback of the finger position (frame). Pointing accuracy increases with feedback about the finger or visual environment. In the finger and frame conditions, the 95% confidence regions of the variable errors have an ellipsoidal distribution with the main axis oriented toward the subjects' head. During the 1-s period when the target is visible, gaze is almost on target. However, gaze drifts away from the target relative to the subject in the delay period after target disappearance. In the finger and frame conditions, gaze returns toward the remembered target during pointing. In all 3 feedback conditions, the correlations between the variable errors of gaze and pointing position increase during the delay period, reaching highly significant values at the time of pointing. Our results demonstrate that gaze affects the accuracy of pointing. We conclude that the covariance between gaze and pointing position reflects a common drive for gaze and arm movements and an effect of gaze on pointing accuracy at the time of pointing. Previous studies interpreted the orientation of variable errors as indicative for a frame of reference used for pointing. Our results suggest that the orientation of the error ellipses toward the head is at least partly the result of gaze drift in the delay period. 相似文献
45.
Henriques DY Medendorp WP Gielen CC Crawford JD 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,152(1):70-78
Eye–hand coordination is geometrically complex. To compute the location of a visual target relative to the hand, the brain must consider every anatomical link in the chain from retinas to fingertips. Here we focus on the first three links, studying how the brain handles information about the angles of the two eyes and the head. It is known that people, even in darkness, reach more accurately when the eye looks toward the target, rather than right or left of it. We show that reaching is also impaired when the binocular fixation point is displaced from the target in depth: reaching becomes not just sloppy, but systematically inaccurate. Surprisingly, though, in normal Gaze-On-Target reaching we found no strong correlations between errors in aiming the eyes and hand onto the target site. We also asked people to reach when the head was not facing the target. When the eyes were on-target, people reached accurately, but when gaze was off-target, performance degraded. Taking all these findings together, we suggest that the brain's computational networks have learned the complex geometry of reaching for well-practiced tasks, but that the networks are poorly calibrated for less common tasks such as Gaze-Off-Target reaching. 相似文献
46.
McDonald EM Gielen AC Trifiletti LB Andrews JS Serwint JR Wilson ME 《Health promotion practice》2003,4(2):129-137
The Johns Hopkins Children's Safety Center (CSC) is a unique health care provider and patient education resource that elevates the attention injury prevention receives in a medical setting and reduces barriers to injury prevention experienced by low-income, urban families, the Center's priority population. This article describes the CSC's development, implementation, and selected elements of its evaluation. Because evaluation has played an important role in the CSC from its inception through its implementation and sustainability, three evaluation activities are described: process evaluation to monitor activity, impact evaluation to understand its effects on parents' safety behaviors, and qualitative interviews with CSC visitors and non-visitors to enhance services. Implications of each evaluation activity are described and recommendations are made for strengthening the CSC. 相似文献
47.
Karen A. McDonnell Andrea Carlson Gielen Patricia O’Campo 《Journal of urban health》2003,80(3):494-509
Women living in poor urban communities are doubly disadvantaged with regard to increased risk for two major public health crises in the United States today--HIV/AIDS (human immunodeficiency virus/acquired immunodeficiency syndrome) and violence. This study moves beyond the comparison of rates of lifetime abuse among women to incorporate contextual information of the abusive situation and experiences of HIV-positive women and a sample of sociodemographically similar HIV-negative women. A total of 611 women, 310 of whom were diagnosed as HIV positive, provided interviews integrating quantitative data and qualitative text on their lifetime experience of abuse. Quantitative results yielded few statistically significant differences between the lifetime experiences of violence between HIV-positive women and their HIV-negative counterparts. Of the women, 62% reported intimate partner violence, and 38% reported experiencing nonpartner abuse as an adult. A majority of the abused women reported that their alcohol or drug use or their partner's alcohol or drug use was associated with the abuse experienced. Significant differences were found between HIV-positive women and HIV-negative women in the pattern of abuse experienced as a child, the frequency of abuse as an adult, and the involvement of women's drinking before or during a violent episode. Qualitative excerpts from the interviews were found to differ thematically and were integrated with the quantitative data to provide a more comprehensive understanding of the women's contextual situation in understanding interpersonal violence experienced by both HIV-positive and HIV-negative women. 相似文献
48.
Exercise training has assumed a major role in cardiac rehabilitation, mostly because of its positive effects on myocardial perfusion in patients with coronary artery disease. The mechanisms involved in mediating this key effect have long been debated: both regression of coronary artery stenosis and improvement of collateralization have been suggested as potential adaptations. However, the comparatively minute changes in luminal diameter and myocardial contrast staining do not fully explain the significant changes in myocardial perfusion. During the last decade, endothelial dysfunction was identified as a trigger of myocardial ischemia. The impaired production of endothelium-derived nitric oxide (NO) in response to acetylcholine and flow leads to paradoxic vasoconstriction and exercise-induced ischemia. Recently, it was confirmed in humans that training attenuates paradoxic vasoconstriction in coronary artery disease and increases coronary blood flow in response to acetylcholine. Data from cell-culture and animal experiments suggest that shear stress acts as a stimulus for the endothelium to increase the transport capacity for L-arginine (the precursor molecule for NO), to enhance NO synthase activity and expression, and to increase the production of extracellular superoxide dismutase, which prevents premature breakdown of NO. Exercise also affects the microcirculation, where it sensitizes resistance arteries for the vasodilatory effects of adenosine. These novel findings provide a pathophysiological framework to explain the improvement of myocardial perfusion in the absence of changes in baseline coronary artery diameter. Because endothelial dysfunction has been identified as a predictor of coronary events, exercise may contribute to the long-term reduction of cardiovascular morbidity and mortality. 相似文献
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50.
Mixed-signal template-based reduction scheme for stimulus artifact removal in electrical stimulation
Thi Kim Thoa Nguyen Silke Musa Wolfgang Eberle Carmen Bartic Georges Gielen 《Medical & biological engineering & computing》2013,51(4):449-458
Simultaneous electrical stimulation and recording are used to gain insights into the function of neuronal circuitry. However, artifacts produced by the electrical stimulation pulses prevent the recording of neural responses during, and a short period after, the stimulation duration. In this work, we describe a mixed-signal recording topology with template subtraction for removing the artifact during the stimulation pulse. Emulated artifacts generated from a lumped electrical circuit model and experimental artifacts in cardiac cell cultures are used to evaluate the topology. The simulations show that delays between the emulated artifact and its estimated compensation template represent the largest error source of the analog template subtraction. The quantization error appears like random noise and determines the threshold level for the action potential detection. Simulations show that removal of the artifacts is possible, allowing the detection of action potentials during the stimulation pulsing period, even for high-amplitude saturating artifacts. Measurement results with artifacts elicited in cardiac cell cultures show feasible applications of this topology. The proposed topology therefore promisingly opens up a previously unavailable detection window for improving the analysis of the neuronal activity. 相似文献