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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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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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A series of [[(tetrazol-5-ylaryl)oxy]methyl]acetophenones was synthesized and evaluated as antagonists of leukotriene D4 induced contractions of guinea pig ileum. Substitutions at the 3-position of the acetophenone with ethyl (66), propyl (68), butyl (83), and isobutyl (84) gave -log IC50 values of 7.9, 8.0, 7.8, and 7.7, respectively. Equally potent compounds were obtained when the tetrazol-5-yl group was connected to the second benzene ring in the para position with a chemical bond (67), methylene (68), or ethylene (71). For retention of high antagonist activity, the acetophenone should be substituted in the 2-position by a hydroxyl group and the tetrazole ring should have an acidic hydrogen atom. 1-[2-Hydroxy-3-propyl-4-[[4-(1H-tetrazol-5-ylmethy) phenoxy]methyl]phenyl]ethanone (68, LY1632443) has undergone extensive pharmacologic evaluation for its potential as an antiasthma agent.  相似文献   
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The activity of the homeobox gene Prox1 is necessary and sufficient for venous blood endothelial cells (BECs) to acquire a lymphatic endothelial cell (LEC) fate. We determined that the differentiated LEC phenotype is a plastic, reprogrammable condition that depends on constant Prox1 activity for its maintenance. We show that conditional down-regulation of Prox1 during embryonic, postnatal, or adult stages is sufficient to reprogram LECs into BECs. Consequently, the identity of the mutant lymphatic vessels is also partially reprogrammed as they acquire some features typical of the blood vasculature. siRNA-mediated down-regulation of Prox1 in LECs in culture demonstrates that reprogramming of LECs into BECs is a Prox1-dependent, cell-autonomous process. We propose that Prox1 acts as a binary switch that suppresses BEC identity and promotes and maintains LEC identity; switching off Prox1 activity is sufficient to initiate a reprogramming cascade leading to the dedifferentiation of LECs into BECs. Therefore, LECs are one of the few differentiated cell types that require constant expression of a certain gene to maintain their phenotypic identity.  相似文献   
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