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Little is known on cross-modal interaction in complex object recognition. The factors influencing this interaction were investigated using simultaneous presentation of pictures and vocalizations of animals. In separate blocks, the task was to identify either the visual or the auditory stimulus, ignoring the other modality. The pictures and the sounds were congruent (same animal), incongruent (different animals) or neutral (animal with meaningless stimulus). Performance in congruent trials was better than in incongruent trials, regardless of whether subjects attended the visual or the auditory stimuli, but the effect was larger in the latter case. This asymmetry persisted with addition of a long delay after the stimulus and before the response. Thus, the asymmetry cannot be explained by a lack of processing time for the auditory stimulus. However, the asymmetry was eliminated when low-contrast visual stimuli were used. These findings suggest that when visual stimulation is highly informative, it affects auditory recognition more than auditory stimulation affects visual recognition. Nevertheless, this modality dominance is not rigid; it is highly influenced by the quality of the presented information. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Shlomit Yuval-GreenbergEmail:
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Unprotected and prolonged exposure to ultraviolet (UV) light from sunlight, lasers, and arc welding leads to outer retinal damage. The photoreceptors and retinal pigment epithelium located in the posterior pole are particularly susceptible to this radiation. Classically known as solar retinopathy, this disorder frequently affects young individuals who have clear lenses and a propensity toward observing solar eclipses. Various imaging techniques aid the clinician in diagnosis, even if patients cannot recall an exposure event. By far the most utilized technique is optical coherence tomography that, in tandem with fluorescein angiography, and fundus autofluorescence, is crucial in ruling out other conditions. Fortunately, the prognosis of acute UV retinopathy is favorable, as most cases fully recover; however, a significant percentage of patients suffer from chronic sequelae: reduced acuity and lifelong central/paracentral scotomas. Thus, education toward understanding UV exposure risks, coupled with either abstinence or proper eye protection, is critical in preventing macular damage. We outline the various etiologies responsible for UV-induced retinopathy, describe the limited treatments available, and provide recommendations to minimize the potential devastating ophthalmic consequences as our society increases its reliance on UV-emitting technology and further engages in solar eclipse viewing.  相似文献   
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Transplants across human leukocyte antigen barriers.   总被引:14,自引:0,他引:14  
Clinical experience with full haplotype-mismatched stem cell transplants has a 20-year history. Early results in leukemia patients were disappointing because of a high incidence of severe graft-versus-host disease (GvHD) in T-replete transplants or high rejection rates in T-cell-depleted transplants. The breakthrough came with introduction of a megadose T-cell-depleted progenitor cell transplant following a high-intensity conditioning regimen and the realization that donor natural killer (NK) cell alloreactivity also plays a role in facilitating engraftment and in preventing relapse. Treating end-stage patients inevitably confounded clinical outcome in early pilot studies. Today, high-risk acute leukemia patients are treated at less advanced stages of disease, receive a reasonably well-tolerated conditioning regimen, and benefit from advances in post-transplant immunological reconstitution. These factors have markedly reduced transplant-related mortality. Overall, event-free survival (EFS) and transplant-related mortality (TRM) compare favorably with reports from unrelated matched transplants. T-cell-depleted megadose stem cell transplant from a mismatched family member, who is immediately available, can now be offered as a viable option to candidates with high-risk acute leukemias.  相似文献   
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Cytotoxic T lymphocytes (CTLs) suppress T cell responses directed against their antigens regardless of their own T cell receptor (TCR) specificity. This makes the use of CTLs promising for tolerance induction in autoimmunity and transplantation. It has been established that binding of the CTL CD8 molecule to the major histocompatibility complex (MHC) class I α3 domain of the recognizing T cell must be permitted for death of the latter cell to ensue. However, the signaling events triggered in the CTL by this molecular interaction in the absence of TCR recognition have never been clarified. Here we use single-cell imaging to study the events occurring in CTLs serving as targets for recognition by specific T cells. We demonstrate that CTLs actively respond to recognition by polarizing their cytotoxic granules to the contact area, releasing their lethal cargo, and vigorously proliferating. Using CTLs from perforin knockout (KO) mice and lymphocyte specific kinase (Lck) knockdown with specific small interfering RNA (siRNA), we show that the killing of the recognizing CD8 T cell is perforin dependent and is initiated by Lck signaling in the CTL. Collectively, these data suggest a novel mechanism in which the entire cascade generally triggered by TCR engagement is "hijacked" in CTLs serving as targets for T cell recognition without TCR ligation.  相似文献   
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The population in the western world has been aging while the cancer survival rates have been systematically increasing. Knowledge is lacking about psychological processes and effects of gender difference among middle-aged cancer patients and their healthy spouses. This study assesses psychological distress, coping and social support among middle-aged couples, where one of the partners was diagnosed with colon cancer. A repeated-measure MANOVA and Pearson's correlation coefficient were used to assess the relationships between the variables. Levels of social support were found to be negatively correlated to levels of psychological distress among all of the participants. Surprisingly, men (healthy or sick) were found to be more distressed than their wives (p<0.0001). Men also reported receiving more support from their wives than did the female spouses (p<0.0005). The gender differences found in our study imply that men (healthy or sick) tend to receive more support than they give to their wives. It also implies that men do not use the support they receive as effectively as their wives. Thus, although men report higher levels of support from their spouses, they also report higher levels of psychological distress. Practical implications are discussed.  相似文献   
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PurposeRecent publications suggested that the risk for pre-eclampsia (PE) is higher with frozen-thawed embryo transfers (FETs) compared to fresh transfers (IVF-ETs). These studies were based on old data that reflects outdated practices. In this paper, we wanted to assess the incidence of PE in current assisted reproductive technology (ART) practice.MethodsIn this cohort study, we present the incidence of PE in all births in the province of Ontario, Canada, for the years 2013–2017 for FET, IVF-ET, and natural conceptions (NC). We also compare our findings to previous studies in a meta-analysis that includes over 4 million births.ResultsThe results of our study show that contemporary practice of ART results in comparable risk for PE between FET and IVF-ET; however, the risk is higher than NC.ConclusionCurrent ART practice is associated with a lower risk for PE in frozen embryo transfer; this RR can be further attenuated by using ovulatory endometrial preparation for FETs.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10815-021-02061-z.  相似文献   
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