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We report on neuropsychological testing done with a family in which many members reported severe face recognition impairments. These 10 individuals were high functioning in everyday life and performed normally on tests of low-level vision and high-level cognition. In contrast, they showed clear deficits with tests requiring face memory and judgements of facial similarity. They did not show deficits with all aspects of higher level visual processing as all tested performed normally on a challenging facial emotion recognition task and on a global-local letter identification task. On object memory tasks requiring recognition of particular cars and guns, they showed significant deficits so their recognition impairments were not restricted to facial identity. These results strongly suggest the existence of a genetic condition leading to a selective deficit of visual recognition.  相似文献   
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An evaluation of two commonly used tests of unfamiliar face recognition   总被引:1,自引:0,他引:1  
The Warrington Recognition Memory for Faces (RMF) and the Benton Facial Recognition Test (BFRT) are commercially available tests that are commonly used by clinicians and cognitive neuropsychologists to evaluate unfamiliar face recognition. Yet, it is not clear that a normal score on either instrument demonstrates normal unfamiliar face recognition. Because the RMFs stimuli contain abundant non-internal facial feature information, subjects may be able to score in the normal range without using internal facial features. On the BFRT, subjects commonly rely on feature matching strategies using the hairline and eyebrows rather than recognizing the facial configuration. To test whether these routes to recognition can support normal performance, normal subjects were tested with versions of the RMF and the BFRT in which the faces had been painted over in a way that prevented the operation of some of the procedures normally involved with face recognition. Even though these modifications removed all of the internal feature information in the RMF, many subjects scored in the normal range, and despite precluding the use of configural processing in the BFRT, many of the scores were in the normal range. As a result, it is apparent that normal scores on these tests do not demonstrate normal unfamiliar face recognition and so clinicians should be cautious in interpreting scores in the normal range. Finally, these results place in question models supported by dissociations involving normal performance on these tests.  相似文献   
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Background: Forty percent of patients with colorectal cancer develop mutations in the K-ras gene.Objective: Our objective was to evaluate whether the presence of c-K-ras gene mutations is a useful tumor-response marker in patients with locally advanced rectal cancer treated with preoperative chemoradiotherapy.Material and Methods: Thirty seven patients with locally advanced rectal cancer were treated with preoperative chemoradiotherapy. Four to six weeks later, surgery was performed. Specimens were classified according to the UICC-AJC classification. A segment of the tumor was obtained to analyze specific c-K-ras gene mutations. Restriction fragment length polymorphism (RFLP) and single strand confirmation polymorphism (SSCP) techniques were used with a set of probes to detect specific c-K-ras mutations in codons 12, 13, and 61. The 37 patients were divided into Group A (with mutations) and Group B (without mutations).Results: All 37 patients completed the scheduled treatment. Group A consisted of 12 patients, whose tumors were classified and specific c-K-ras mutations were located as follows: eight in codon 12, two in codon 13, and one in codon 61. Group B consisted of 25 patients. The tumors were classified and there were more early-stage tumors in Group A, whereas in Group B there were more advanced-stage tumors (P 5 .05, respectively). The mean follow-up was 36.2 6 18.3 months. All Group A patients survived, whereas 8 of the 25 patients in Group B died due to progressive metastatic disease. Survival in Group A was 100%, whereas in Group B it was 59% (P 5 .03).Conclusions: The presence of specific c-K-ras mutations is an indicator of tumor response in patients with locally advanced rectal cancer treated with preoperative chemoradiotherapy and surgery. Therefore, responding patients may be more amenable to less radical surgical procedures based on c-K-ras mutations.  相似文献   
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This study of etoposide in thyroid cancer was designed to determine the activity and toxicity of etoposide in a variety of inoperable, thyroid hormone insensitive, and radio-iodine resistant primary cancers of the thyroid. The patients were required to have an ECOG performance status of at least 3 and no previous exposure to chemotherapy. The etoposide was given at a dose of 140 mg/m2 daily for 3 days and every 3 weeks until progression. The study was closed after 18 months because of poor accrual. There were no responses seen among the 10 patients accrued. The toxicity was primarily hematologic. There was no evidence of activity of etoposide in thyroid carcinoma, although this study lacked significant power because of the poor accrual.  相似文献   
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This review of developmental disorders of vision focuses on only a few of the many disorders that disrupt visual development. Given the enormity of the human visual system in the primate brain and complexity of visual development, however, there are likely hundreds or thousands of types of disorders affecting high-level vision. The rapid progress seen in developmental dyslexia and WMS demonstrates the possibilities and difficulties inherent in researching such disorders, and the authors hope that similar progress will be made for congenital prosopagnosia and other disorders in the near future.  相似文献   
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Air contamination in sawmills can cause respiratory health problems. The authors measured respirable dust, bacteria, endotoxins, and molds collected from 17 sawmills in eastern Canada. A total of 1,205 sawmill workers answered a respiratory-health questionnaire, and they all participated in lung-function measurements, skin-prick tests, and venous blood sampling for specific immunoglobulins against molds found in the sawmills. Workers had normal lung functions, and most respiratory symptoms could be explained by smoking histories. Workers in pine sawmills had a greater prevalence of positive skin-prick test to pine than did workers in sawmills where other woods were used. High levels of specific antibodies were seen in some workers. The presence of a positive skin-prick test and/or specific antibodies had no impact on lung function(s). These Quebec sawmill workers did not experience significant respiratory illnesses; however, some of these workers may be at a higher risk of developing asthma and hypersensitivity pneumonitis than nonworkers.  相似文献   
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