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Schizophrenic patients and their first-degree relatives exhibit deficits in the anti-saccade task. In the present study, anti-saccade task performance was examined in subjects with 'high' and 'low' expressions of the schizotypal personality trait. For that purpose, the SPQ-G, the German adaptation of the Schizotypal Personality Questionnaire (SPQ; Raine, 1991), was filled in by 489 university students. Twenty and 21 participants with 'high' and 'low' SPQ-G scores, respectively, were compared with respect to saccadic eye movements elicited under the overlap and 200 ms gap conditions of the pro- and anti-saccade tasks. Each task block comprised 150 trials, 75 to either side in random order. The order of presentation of the task blocks was counterbalanced across the participants of each group. Saccadic reaction times were slower during the anti- as compared to the pro-saccade task and under the overlap as compared to the gap condition. Direction errors occurred almost exclusively during the anti-saccade task, express saccades mainly under the pro-saccadic gap condition. High-schizotypal participants did not differ significantly from low-schizotypal participants in any of these measures. While these results might suggest normal anti-saccade task performance in schizotypal personality as defined by the SPQ-G, the sampling strategy adopted in the present study is the more plausible explanation for the lack of group differences.  相似文献   
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Elimination of the eosinophils from the airways by selective induction of apoptosis represents a therapeutic approach for asthma. Here we report on a possible target molecule, the surface receptor CD69. To simulate an asthmatic response, segmental allergen challenge in mild asthmatics was performed. Eosinophil numbers increased in bronchoalveolar lavage (BAL) at 18 h. In contrast to blood cells, BAL eosinophils expressed the activation marker CD69. Purified blood eosinophils stimulated with granulocyte/macrophage colony-stimulating factor (GM-CSF) or interferon-gamma (IFN-gamma) expressed CD69 and showed prolonged viability. Only IFN-gamma enhanced constitutive CD95 expression. Coincubation with anti-CD69 or anti-CD95 monoclonal antibody (MoAb) induced apoptosis, as revealed by propidium iodide incorporation, membrane blebbing and nuclear fragmentation. Additionally, both anti-CD69 and anti-CD95 MoAb reduced cytokine-enhanced Bcl-2 expression. In conclusion, CD69 transduces a Bcl-2-dependent death signal when ligated by a specific antibody. As, in contrast to the ubiquitous death-inducer CD95, the function of CD69 appears to be restricted to activated eosinophils, it represents an ideal target for therapeutic intervention in asthma.  相似文献   
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Radiotherapy is the highly effective standard in the treatment of choroidal metastasis. Visual acuity can be stabilized or increased in about 70-80% of eyes treated, thus prevailing the quality of life in these worse prognostic patients. In about 30-40% bilateral macroscopic disease is found at diagnosis. The best treatment for unilateral metastasis remains controversial: unilateral or bilateral irradiation for sterilization of suspected contralateral metastasis or unilateral irradiation without irradiation of the contralateral choroidea. In the analysis of a prospective study (ARO 95-08) 35 out of 50 patients with choroidal metastasis had unilateral disease and received unilateral irradiation with a lateral field using 6 MeV-photons (40 Gy in 20 fractions) without sparing the contralateral choroidea. Therefore the posterior contralateral choroidea received 50-70% of the total dose (20-28 Gy) for suspected micrometastasis. None of these patients developed contralateral choroidal metastasis during the median follow up time of 11.5 months. A unilateral field with 40 Gy for unilateral choroidal metastasis without sparing the contralateral choroidea seems to be effective in destroying contralateral micrometastasis with a lower risk of late side effects compared with bilateral fields.  相似文献   
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There are few studies on the development of oculomotor functions during childhood. B. Fischer, M. Biscaldi, and S. Gezeck (1997) reported improvement of antisaccade task performance between ages 6 and 16 years. The present study is a replication and extension of those results. In three age groups (6-7, 10-11, 18-26 years), saccades during pro- and antisaccade tasks with 200-ms gap and overlap and during a fixation task were measured. Adults exhibited faster saccades and less prosaccades during the antisaccade tasks than 10-11-year-old children; these two groups had faster saccades during all tasks and less prosaccades during the anti- and the fixation task than 6-7-year-old subjects. Both children groups made more express saccades than adults. Results suggest different degrees of age-related improvement for different saccadic parameters, the effects being greatest for prosaccade inhibition during the antisaccade task and in line with the assumed protracted development of prefrontal functions.  相似文献   
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Background: To evaluate the significance of angioma number (single or multiple) for the presence of von Hippel-Lindau (VHL) disease in patients presenting with capillary retinal angioma. Methods: Forty-one nonrelated patients presenting with capillary retinal angioma were evaluated. An ophthalmic workup, screening for other organ lesions, and molecular genetic screening for a mutation of the VHL gene was performed. The diagnosis of VHL was made on the basis of the personal and family history, the presence of other VHL-associated organ lesions, or the presence of a mutation of the VHL gene. Results: Thirteen patients (32%) presented with a single angioma and 28 patients (68%) presented with multiple angiomas. In 81% of all patients, VHL could be diagnosed. Diagnosis of VHL could be readily made by the personal or family history in 51% of all patients. In another 27% of all patients, VHL disease was evidenced by screening for other VHL-associated lesions. In two patients (3%) VHL could be diagnosed by molecular genetics only. All patients with multiple retinal angiomas had VHL disease and, in 38% of patients with a single angioma, VHL was present. Reasons for a missing family history in patients with VHL disease were the presence of a de novo mutation (15% of VHL patients) or clinical anticipation of VHL disease (18% of VHL patients). Conclusion: The presence of multiple retinal angiomas strongly suggests VHL disease, which, however, can be obscured by presence of a de novo mutation or by clinical anticipation of VHL disease in affected families. A single retinal angioma may be sporadic as well as the presenting sign of VHL. Diagnosis and screening for this multitumor syndrome is substantially supported by molecular genetics. Received: 7 February 2000 Revised: 22 May 2000 Accepted: 29 June 2000  相似文献   
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