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Nerve conduction studies in adrenomyeloneuropathy.   总被引:5,自引:1,他引:4       下载免费PDF全文
OBJECTIVE--Adrenomyeloneuropathy (AMN) is an X linked metabolic disorder presenting with progressive spastic paraparesis in the third to fifth decade of life. Although peripheral neuropathy is also present in most patients, prominent pyramidal signs may make its clinical recognition difficult. The objective was to characterise the peripheral neuropathy in patients with AMN by nerve conduction studies. METHODS--Nerve conduction studies were performed in 99 men known to have AMN and in 38 heterozygous women, all of whom had neurological disabilities. RESULTS--Of the 13 variables obtained, at least one was abnormal in 82% of patients. The abnormalities were more common in men than in women (87% v 67%); in legs than in arms (77% v 38%); in motor than in sensory conduction (80% v 39%); and in latency (distal and F wave) and velocity compared with amplitude (80% v 29%). Twenty six patients had at least one nerve variable value in the demyelinating range. Four variables (sural velocity, peroneal amplitude, peroneal velocity, and peroneal F wave) were correlated with the expanded disability status scale; five variables (peroneal velocity, tibial H reflex, median distal latency, median conduction velocity, and median F wave latency) were correlated with serum very long chain fatty acids (VLCFAs); and two variables (sural amplitude and peroneal distal latency) were more likely to be abnormal in patients with normal adrenal function than in patients with Addison's disease. CONCLUSIONS--Nerve conduction studies in patients with AMN are often abnormal and suggest a mixture of axonal loss and multifocal demyelination. Their correlation with disability status and serum VLCFAs suggests that measures from nerve conduction studies may be useful in evaluating future treatments.  相似文献   
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FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease.  相似文献   
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Development of a new wound dressing with antimicrobial delivery capability   总被引:1,自引:0,他引:1  
A bilaminar wound dressing composed of an outer membrane and an inner three-dimensional matrix of a fabric or a sponge may be considered to constitute an ideal structure that promotes wound healing: the outer membrane prevents body fluid loss, controls water evaporation, and protects the wound surface from bacterial invasion, and the inner matrix encourages adherence by tissue growth into the matrix. Using this concept, we developed a biosynthetic wound dressing with a drug delivery capability. This medicated wound dressing is composed of a spongy sheet of a chitosane derivative and collagen mixture that is laminated to an antimicrobial-impregnated polyurethane membrane. In this study, a gentamycin sulfate-impregnated wound dressing was prepared and evaluated. The antimicrobial efficacy of this wound dressing was examined on an agar plate seeded with Pseudomonas aeruginosa. Also, the cytotoxicity of an antimicrobial released from this wound dressing was examined in an in vitro system with cultured skin substitutes. Both in vitro tests have shown that this wound dressing is capable of suppressing bacterial growth and minimizing cellular damage. In addition, in the treatment of wounds inflicted on rats and rabbits, this wound dressing was shown to be efficacious in covering full-thickness and split-thickness skin defects. Finally, the efficacy of this wound dressing was evaluated in a nonrandomized open-label study of 31 clinical cases. In 31 cases treated with this wound dressing, good or excellent wound healing was achieved.  相似文献   
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The use of self-expanding prostheses in the management of malignant oesophageal strictures has become well established. The majority of benign peptic oesophageal strictures can be successfully managed using endoscopic or fluoroscopically guided balloon oesophageal dilatation combined with long-term drug therapy, particularly using proton pumper inhibitors. Although endoscopic oesophageal dilatation can be performed on an outpatient basis, it requires repeated hospital visits. There is a small risk of oesophageal perforation whilst cardio-respiratory complications may be encountered during the use of intravenous sedation in an elderly population. The use of a self-expanding Strecker stent in a 98 year old woman with a benign oesophageal stricture is described.  相似文献   
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Lynch  DA; Gamsu  G; Ray  CS; Aberle  DR 《Radiology》1988,169(3):603-607
In 260 asbestos-exposed individuals evaluated by means of computed tomography (CT), 43 unsuspected pulmonary masses were found in 27 individuals. The masses included fissural pleural plaques (n = 10), dense fibrotic bands (n = 3), round atelectasis (n = 11), carcinomas (n = 3), and other presumed benign masses (n = 16). The most helpful features in the diagnosis of rounded atelectasis with CT were (a) contiguity to areas of diffuse pleural thickening, (b) a lentiform or wedge-shaped outline, (c) evidence of volume loss in the adjacent lung, and (d) a characteristic "comet tail" of vessels and bronchi sweeping into the margins of the mass. Less advanced areas of focal atelectasis had fewer classic features. Intrafissural pleural plaques were readily identified with high-resolution CT. In asbestos-related masses, the demonstration of stability over time is necessary. Careful interpretation of CT and high-resolution CT features and close surveillance can obviate the need for biopsy in the majority of instances.  相似文献   
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