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Background  

Shoulder disorders are a common health problem in western societies. Several treatment protocols have been developed for the clinical management of persons with shoulder pain. However available evidence does not support any protocol as being superior over others. Systematic reviews provide some evidence that certain physical therapy interventions (i.e. supervised exercises and mobilisation) are effective in particular shoulder disorders (i.e. rotator cuff disorders, mixed shoulder disorders and adhesive capsulitis), but there is an ongoing need for high quality trials of physical therapy interventions. Usually, physical therapy consists of active exercises intended to strengthen the shoulder muscles as stabilizers of the glenohumeral joint or perform mobilisations to improve restricted mobility of the glenohumeral or adjacent joints (shoulder girdle). It is generally accepted that a-traumatic shoulder problems are the result of impingement of the subacromial structures, such as the bursa or rotator cuff tendons. Myofascial trigger points (MTrPs) in shoulder muscles may also lead to a complex of symptoms that are often seen in patients diagnosed with subacromial impingement or rotator cuff tendinopathy. Little is known about the treatment of MTrPs in patients with shoulder disorders.  相似文献   
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BACKGROUND: Cyclosporin has been shown to facilitate renal vasoconstriction and to have an antinatriuretic effect. The existence of an interference of cyclosporin with the vasodilating properties of endothelium mediated by nitric oxide production could mediate these effects. On the other hand, the infusion of the nitric oxide precursor L-arginine has been shown to induce renal vasodilatation and to facilitate natriuresis in normal volunteers. We have investigated the renal effects of the administration of an infusion of L-arginine in renal transplant patients chronically treated with cyclosporin. To facilitate the analysis of the data the effects of the administration of a similar dose of cyclosporin on renal function during the infusion of a vehicle were also investigated during the administration of a vehicle of L-arginine. DESIGN: Ten male renal transplant patients, chronically treated with cyclosporin and with a stable renal function were studied during 2 consecutive days after the administration of the usual morning dose of cyclosporin. The first day they received an intravenous infusion of vehicle and the second the infusion of graded doses of L-arginine (50, 100, 150 mg/kg/h) during 3 consecutive h. RESULTS: The first day, after cyclosporin administration a significant fall (P < 0.01) was observed in natriuresis and kaliuresis in the absence of changes in renal plasma flow and glomerular filtration rate. After the administration of L-arginine significant (P < 0.01) increases of renal plasma flow, glomerular filtration rate, and natriuresis were seen. The increase in blood levels of cyclosporin after its administration did not differ between days 1 and 2. CONCLUSION: These results indicate that L-arginine facilitates renal vasodilatation and natriuresis in renal transplant patients. Furthermore, the observed increase in sodium excretion could indicate that L-arginine counteracts the antinatriuretic effect of cyclosporin.   相似文献   
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Longitudinal changes in IQ among mentally retarded (MR) fragile X [fra(x)] males have been reported previously. While age is associated with decline in IQ, not all males are so affected. This suggests that there may be more than one subtype of affected fra(X) male. Therefore, we examined the distribution of standardized difference scores (Zdiff) in IQ to determine if subjects were from an admixture of at least 2 populations. Cluster analysis of Zdiff scores was used to partition subjects into 2 groups. Goodness-of-fit tests indicated that scores were more likely to come from an admixture. Discriminant functions (DF) were calculated to determine predictive validity of Zdiff scores. To eliminate the effect of skewing, a power transform was applied to Zdiff scores and DFs recomputed. Zdiff and transformed scores provided similar results. The mean and variance for one group showed no differences in test-retest scores as would be expected from examining any population while the mean for the second group indicated significant decline in IQ nearly 4 standard errors below the first test score. These results suggest that there may be clinical evidence for 2 types of fra(X) mutation: One which causes MR but is static, and a second mutation which causes MR but is dynamic and contributes to an apparent longitudinal decline in cognitive function.  相似文献   
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Does altered biomechanics cause marrow edema?   总被引:21,自引:0,他引:21  
Schweitzer  ME; White  LM 《Radiology》1996,198(3):851
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The peroxisome biogenesis disorders (PBDs) with generalized peroxisomal dysfunction include Zellweger syndrome (ZS), neonatal adrenoleukodystrophy (NALD), and infantile Refsum disease (IRD). There is clinical, biochemical, and genetic overlap among the three phenotypes, also known as Zellweger spectrum disorders. Clinical distinctions between the phenotypes are not sharply defined. Only limited sources are available to serve as a background for prognosis in PBD, especially in case of prolonged survival. We delineated the natural history of 31 PBD patients (age 1.2-24 years) through systematic clinical and biochemical investigations. We excluded classical ZS from our study, and included all patients with a biochemically confirmed generalized peroxisomal disorder over 1 year of age, irrespective of the previously diagnosed phenotype. The initial clinical suspicion, age at diagnosis, growth, development, neurological symptoms, organ involvements, and survival are summarized. Common to all patients were cognitive and motor dysfunction, retinopathy, sensorineural hearing impairment, and hepatic involvement. Many patients showed postnatal growth failure, 10 patients displayed hyperoxaluria of whom 4 had renal stones. Motor skills ranged from sitting with support to normal gait. Speech development ranged from non-verbal expression to grammatical speech and comprehensive reading. The neurodevelopmental course was variable with stable course, rapid decline with leukodystrophy, spinocerebellar syndrome, and slow decline over a wide range of faculties as outcome profiles. At the molecular level, 21 patients had mutations in the PEX1 gene. The two most common PEX1 mutations were the G843D (c.2528G-->A) missense and the c.2097insT frameshift mutation. Patients having the G843D/G843D or the G843D/c.2097insT genotypes were compared. Patients homozygous for G843D generally had a better developmental outcome. However, one patient who was homozygous for the "mild" G843D mutation had an early lethal disease, whereas two other patients had a phenotype overlapping with the G843D/c.2097insT group. This indicates that next to the PEX1 genotype other yet unknown factors determine the ultimate phenotype.  相似文献   
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