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841.
Dysarthria is an acquired neurogenic sensorimotor speech symptom and an integral part within the clinical spectrum of ataxia syndromes. Ataxia measurements and disability scores generally focus on the assessment of motor functions. Since comprehensive investigations of dysarthria in ataxias are sparse, we assessed dysarthria in ataxia patients using the Frenchay Dysarthria Assessment. The Frenchay Dysarthria Assessment is a ten-item validated test in which eight items focus on the observation of oral structures and speech functions. Fifteen Friedreich's ataxia patients and 15 healthy control individuals were analyzed using clinical and logopedic methodology. All patients underwent neurological assessment applying the Scale for the Assessment and Rating of Ataxia. In Friedreich's ataxia patients, the Frenchay sub-item voice showed to be most affected compared to healthy individuals followed by items such as reflexes, palate, tongue, and intelligibility. Scoring of lips, jaw, and respiration appeared to be mildly affected. Ataxia severity in Friedreich's ataxia patients revealed a significant correlation with the Frenchay dysarthria sum score. The introduction of a binary Adapted Dysarthria Score additionally allowed allocation to distinct dysarthria pattern in ataxias. The Frenchay Dysarthria Assessment proved to be a valid dysarthria measure in Friedreich's ataxia. Its availability in several languages provides a major advantage regarding the applicability in international clinical studies. Shortcomings of the Frenchay test are the multiplicity of items tested and its alphabetic coding. Numerical scoring and condensation of assessments in a modified version may, however, provide an excellent clinical tool for the measurement and scoring of dysarthria in ataxic speech disorders.  相似文献   
842.
Magnetic resonance spectroscopy (MRS) of skeletal muscle has been successfully applied by physiologists over several decades, particularly for studies of high-energy phosphates (by (31)P-MRS) and glycogen (by (13)C-MRS). Unfortunately, the observation of these heteronuclei requires equipment that is typically not available on clinical MR scanners, such as broadband capability and a second channel for decoupling and nuclear Overhauser enhancement (NOE). On the other hand, (1)H-MR spectra of skeletal muscle can be acquired on many routine MR systems and also provide a wealth of physiological information. In particular, studies of intramyocellular lipids (IMCL) attract physiologists and endocrinologists because IMCL levels are related to insulin resistance and thus can lead to a better understanding of major health problems in industrial countries. The combination of (1)H-, (13)C-, and (31)P-MRS gives access to the major long- and short-term energy sources of skeletal muscle. This review summarizes the technical aspects and unique MR-methodological features of the different nuclei. It reviews clinical studies that employed MRS of one or more nuclei, or combinations of MRS with other MR modalities. It also illustrates that MR spectra contain additional physiological information that is not yet used in routine clinical applications.  相似文献   
843.
Archaeological research in the African rainforest reveals unexpected results in the search for the origins of hominoid technology. The ancient Panin sites from C?te d'Ivoire constitute the only evidence of prehistoric ape behavior known to date anywhere in the world. Recent archaeological work has yielded behaviorally modified stones, dated by chronometric means to 4,300 years of age, lodging starch residue suggestive of prehistoric dietary practices by ancient chimpanzees. The "Chimpanzee Stone Age" pre-dates the advent of settled farming villages in this part of the African rainforest and suggests that percussive material culture could have been inherited from an common human-chimpanzee clade, rather than invented by hominins, or have arisen by imitation, or resulted from independent technological convergence.  相似文献   
844.
By using diffusion-weighted imaging (DWI), we have recently shown abnormal diffusivity in the putamen of patients with the Parkinson variant of multiple system atrophy (MSA-P) which also correlated with disease severity, indicating the capability of putaminal diffusivity to serve as a marker for disease progression. We therefore performed a serial DWI study in 10 patients with MSA-P compared to 10 patients with Parkinson's disease (PD) to evaluate the dynamic evolution of diffusion properties in the basal ganglia including putamen, caudate nucleus and globus pallidum by means of the trace of the diffusion tensor (Trace(D)). For comparison, we have also analyzed the frequency and semiquantitative grading of MSA-P-related structural changes on conventional MRI including putaminal atrophy, lateral hyperintense margination of the putamen and putaminal signal hypointensity relative to the globus pallidum on T2 MR images. None of the Trace(D) values in the basal ganglia regions in the PD group changed significantly at follow-up compared to baseline. In MSA-P, a significant increase of the Trace(D) was found in the putamen, which correlated with motor progression as assessed by the Unified Parkinson's Disease Rating Scale (UPDRS). No significant change of any of the abnormal putaminal findings on routine MRI was obtained. We suggest that abnormal diffusivity in the putamen is sensitive to change over time in MSA-P and correlates with motor progression indicating that DWI may serve to monitor disease progression in MSA-P in an objective and quantitative manner.  相似文献   
845.
There is vast evidence for the superiority of agonist treatments (methadone, buprenorphine) over a withdrawal approach in opioid‐dependent populations. Little research, however, has been conducted on the same approach for the treatment of high‐dose benzodiazepine (BZD) dependence. Even large‐scale reviews and meta‐analyses discussing treatment strategies for benzodiazepine‐dependent patients focus solely upon approaches that aim at achieving abstinence, namely on complete BZD withdrawal. While the types of interventions differ (e.g. gradual benzodiazepine taper with a long or a short half‐life benzodiazepine, switching to non‐benzodiazepine anxiolytics or prescribing adjunctive medications such as antidepressants or anticonvulsants on an in‐ or out‐patient basis), the common aim of treatment still is total abstinence from benzodiazepines. However, the majority of patients suffering from high‐dose BZD dependence do not succeed with long‐term abstinence, irrespective of the procedure, and clinicians have been using BZD ‘substitution’ treatment in such cases for decades. Therefore, we suggest the evaluation of a substitution approach in this group, consisting of maintenance treatment with a slow‐onset, long‐acting BZD. Advantages of such a procedure may be improved health, less craving, fewer withdrawal complications, reduced anxiety, increased treatment retention, improvements in social functioning and less illegal activity. Cognitive impairments, the most problematic side effects of substitution treatment with benzodiazepines, could possibly be minimized by using an optimal agonist.  相似文献   
846.
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