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CASE REPORT: The reported female patient underwent sub-total resection of an intra-medullary cervicothoracic astrocytoma classified as WHO grade II in 1984 at the age of 18 months and received local irradiation. In 1989, a local recurrence was diagnosed and a partial resection was performed. Sixteen years later, a small recurrent cervicothoracic tumour was found and spinal seeding to the equine nerve roots and the left cerebellar cortex was apparent on MRI. The patient was implanted with a ventriculoperitoneal shunt for a pseudo-tumour cerebri producing papilloedema, which eventually lead to amaurosis. After an extended biopsy, the invasive lumbosacral tumour was classified as glioblastoma multiforme. Two months later, the patient died after rapid progression of the caudal cranial nerve dysfunction. DISCUSSION AND CONCLUSION: Anaplastic progression and dissemination of spinal astrocytomas even two decades after initial diagnosis and treatment are rare. Therapies and diagnostic follow-up strategies are discussed.  相似文献   
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Letters and speech sounds are the basic units of correspondence between spoken and written language. Associating auditory information of speech sounds with visual information of letters is critical for learning to read; however, the neural mechanisms underlying this association remain poorly understood. The present functional magnetic resonance imaging study investigates the automaticity and behavioral relevance of integrating letters and speech sounds. Within a unimodal auditory identification task, speech sounds were presented in isolation (unimodally) or bimodally in congruent and incongruent combinations with visual letters. Furthermore, the quality of the visual letters was manipulated parametrically. Our analyses revealed that the presentation of congruent visual letters led to a behavioral improvement in identifying speech sounds, which was paralleled by a similar modulation of cortical responses in the left superior temporal sulcus. Under low visual noise, cortical responses in superior temporal and occipito-temporal cortex were further modulated by the congruency between auditory and visual stimuli. These cross-modal modulations of performance and cortical responses during an unimodal auditory task (speech identification) indicate the existence of a strong and automatic functional coupling between processing of letters (orthography) and speech (phonology) in the literate adult brain.  相似文献   
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This multicenter open-label clinical trial was designed to investigate the safety and efficacy of donepezil, a selective acetylcholinesterase inhibitor, in the treatment of Alzheimer's disease (AD) in routine clinical practice in Germany. A total of 237 patients with mild-to-moderate AD were treated with donepezil for 24 weeks, 186 completed the study according to the protocol. In the completer group, mean MMSE score for efficacy showed an improvement from baseline of +1.6 points at week 12 (95% CI +1.1 to +2.1) and of +1.1 points at week 24 (95% CI +0.5 to +1.7). In more than 80% of the patients, global tolerability was rated to be very good or good. There were only insignificant effects on ECG parameters. This study confirms the results obtained in previous double-blind trials, which showed that donepezil is effective and well tolerated in patients with mild-to-moderately severe AD.  相似文献   
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Actinopathies are defined by missense mutations in the ACTA1 gene coding for sarcomeric actin, of which some 70 families have, so far, been identified. Often, but not always, muscle fibers carry large patches of actin filaments. Many such patients also have nemaline myopathy, qualifying actinopathies as a subgroup of nemaline myopathies. This article concerns a then newborn, now 2 1/2-year-old boy, the first and single child of nonconsanguineous parents, who was born floppy, requiring immediate postnatal assisted ventilation. A quadriceps muscle biopsy revealed large patches of thin myofilaments reacting at light and electron microscopic levels with antibodies against actin but only a few sarcoplasmic rods and no intranuclear rods. DNA analysis of the patient's and both parents' blood did not reveal any missense mutation in the ACTA1 gene. Thus, this congenital myopathy can be caused by a new type of ACTA1 gene mutation, a new non-ACTA1 gene mutation, or no mutation at all, designating it as an actin-related myopathy, perhaps a new type of congenital myopathy and a new member of protein aggregate myopathies marked by aggregation of proteins within muscle fibers, among them desminopathies, alpha-beta crystallinopathies, other desmin-related myopathies (also termed myofibrillar myopathies), actinopathies and, now, actin-related myopathies.  相似文献   
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Muscle pathology in 57 patients with myotonic dystrophy type 2   总被引:3,自引:0,他引:3  
We evaluated muscle biopsies from 57 patients with genetically confirmed myotonic dystrophy type 2/proximal myotonic myopathy (DM2/PROMM). Light microscopy showed myopathic together with "denervation-like" changes in almost all biopsies obtained from four different muscles: increased fiber size variation, internal nuclei, small angulated fibers, pyknotic nuclear clumps, and predominant type 2 fiber atrophy. Quantitative morphometry in 18 biopsies that were immunostained for myosin heavy chain confirmed a predominance of nonselective type 2 fiber atrophy. These histological changes were similar in all patients regardless of the site of biopsy, the predominant clinical symptoms and signs, and the clinical course. It is likely that, in a number of undiagnosed patients, DM2 is the underlying disorder. With a better understanding of the histopathological pattern in DM2, biopsies from patients with undiagnosed neuromuscular disorders can now be reevaluated.  相似文献   
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BackgroundA 59-year-old male had a latent epicardial mass discovered at cardiovascular imaging during the assessment of an aortic murmur.ResultsThe resected mass surrounded the left anterior descending coronary artery. It was a well-limited pericoronary cellular lesion. It was made of a mixture of polytypic plasma cells, lymphocytes with lymphoid follicles, hyaline vascular hyperplasia, and focal eosinophils. No immunoglobulin and TCR-γ gene rearrangements were detected. In this immunocompetent patient, HHV-8 was negative.ConclusionThe pattern was consistent with a pericoronary localized Castleman's disease of composite histologic subtype.  相似文献   
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