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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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The modulating effects of caffeine, nicotine, ethanol and sodium selenite on development of N-nitrosobis(2-oxopropyl)-amine (BOP)-initiated pancreatic tumors were investigated. Female Syrian golden hamsters were given s.c. injections of BOP (10 mg/kg body weight) or saline alone once a week for 3 weeks and then administered 2000 p.p.m. caffeine, 25 p.p.m. nicotine, 20% ethanol or 4 p.p.m. sodium selenite in their drinking water for the next 37 weeks. Control animals were given tap water alone after BOP initiation. Only the BOP-treated groups developed pancreatic adenocarcinomas and dysplasias. The multiplicity of pancreatic carcinomas was significantly higher (P less than 0.05) in animals receiving caffeine than in the controls. In addition, caffeine treatment slightly increased the incidence of carcinomas. Nicotine and ethanol also showed tendencies to enhance pancreatic carcinogenesis, although there were statistically no significant differences regarding lesion development. In contrast, sodium selenite administration was associated with a tendency for a decrease in the number of carcinomas and dysplasias. Thus, among these chemicals of obvious significance to human life-style, caffeine enhanced the development of pancreatic tumors when administered during the post-initiation phase in this hamster model.  相似文献   
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To investigate spatial resolution requirements for digitized portal images in radiation therapy, observer performance tests were performed. One hundred twenty portal images were digitized with sampling frequencies of 0.700, 0.350, and 0.175 mm for observation. Receiver operating characteristic analysis was used to determine the acceptable sampling frequency for clinical portal images. The detectability of setup errors was significantly better on the original images than on the digitized images with sampling frequencies of 0.700 mm (P = .005) and 0.350 (P = .046). Some clinical disadvantages might accrue with the use of a sampling frequency of 0.350 mm or larger.  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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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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