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Chronic schizophrenics, acute schizophrenics (N = 18), and normals (N = 9) participated in a memory scanning task in which the visual display consisted of either common words, word-like strings of letters, or randomly arranged letters. Unlike earlier results, the slope of the function that relates reaction time to memory set size was significantly higher for the two schizophrenic groups than for the normal group. Among the chronic schizophrenics only reaction time to word display was higher than to display with random letters. The implications for theories that hypothesize deficits at specific stages of processing among schizophrenics are discussed.  相似文献   
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Underrepresentation of Black individuals in genetic research is a longstanding issue. There are well-documented strategies to improve the enrollment of Black participants; however, few studies explore these strategies—as well as the barriers and facilitators for participation—by sampling Black people who have previously participated in genetic research. This study explores the decision-making process of Black adults who have participated in genetic research to identify best practices in the recruitment of Black subjects in genetic research. We conducted 18 semi-structured interviews with Black adults with prior research participation in genetic studies housed at an urban academic medical center in the United States of America (USA). An online survey was conducted with the participants to gather demographic data and information on prior research participation. Trust in research was ascertained with the Corbie-Smith Distrust in Clinical Research Index. Two participants scored high levels of distrust using the validated index. Using thematic content analysis, 4 themes emerged from the interviews: (1) Participants are active players in health system, (2) information is power, and transparency is key, (3) therapeutic alliances and study characteristics facilitate participation, and (4) race pervades the research process. The decision to participate in genetic research for the participants in our study was prompted by participants’ internal motivations and facilitated by trust in their doctor, trust in the institution, and ease of participation. Most participants viewed their enrollment in genetic research in the context of their own racial identity and the history of medical racism in the USA.  相似文献   
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Glioblastoma multiforme (GBM) is an incurable brain tumor. Due to the striking heterogeneity that characterizes GBM, there is no known tumor-specific antigen or receptor that is expressed by a majority of GBM patients. We found that virtually all studied human GBM specimens (23 samples) abundantly expressed a receptor for interleukin (IL)-13 in situ, whereas normal human brain had few, if any, IL-13-binding sites. The GBM-associated IL-13 receptor was both quantitatively and qualitatively different from and, thus, more restrictive than the shared signaling receptor of normal tissue: it was IL-4 independent. The receptor for IL-13 was overexpressed by a majority of cancer cells in situ. Furthermore, cytotoxins targeted to this more restrictive IL-13R produced cures in animals bearing xenografts of human high-grade gliomas. Thus, unexpectedly, the receptor for an immune regulatory cytokine may be a long sought marker and, concomitantly, a unique imaging site and therapeutic target for GBM, the most malignant and the most heterogeneous of brain tumors.  相似文献   
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PURPOSE: To evaluate the efficacy of transpupillary thermotherapy (TTT) in management of occult subfoveal choroidal neovascularization (CNV) in exudative age-related macular degeneration (AMD). METHODS: Retrospective chart review of eyes that were treated with TTT and had at least 12 weeks of follow-up. Base-line and final ETDRS visual acuity and fluorescein angiography (FA) were compared. RESULTS: For the 48 eyes which met inclusion criteria, mean pre-operative visual acuity was 20/128 (range: 20/50-20/500). Average follow-up was 27 weeks (range: 12 weeks-55 weeks). At 3 months after treatment, 12 eyes (25%) improved 2 lines or more, 18 eyes (37.5%) had no change or 1 line of visual improvement, and 18 eyes (37.5%) worsened 1 or more lines. No significant adverse event was noted during treatment. Three eyes developed large submacular hemorrhage within 2 months of treatment. Based on clinical examination and FA, 61% of the eyes appeared to have reduction of subretinal fluid compared to pre-operative evaluations. CONCLUSION: Visual acuity was stable or improved in 62.5% of eyes in our series and the treatment was well tolerated. Longer follow up and larger number of patients would be required to evaluate the ultimate benefit of TTT in management of occult CNV due to AMD.  相似文献   
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