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Dimensional analysis of animals with regard to those structures and functions which affect the rate of energy metabolism can be conducted on the basis of either geometric or elastic similarity. Predictions of the relationships between various structures and functions and body mass are dependent of the type of similarity assumed. Comparison of the relationships between numerous physiological variables and body mass reported in the literature and those predicted from geometric and elastic similarity indicates that the preponderance of predictions from elastic similarity are in better agreement with the observed values than are the predictions from geometric similarity. It appears that the components of the cardiovascular system are scaled in accordance with elastic similarity. For this reason, cardiac output is proportional to body mass raised to the 3/4 power. The biochemical basis for the relationship between cardiac output and the rate of energy metabolism is discussed.  相似文献   
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Although magnetic resonance imaging has a high sensitivity for cerebral and spinal tumors, demonstration of small lesions can be difficult. In a patient with multiple extra- and intraspinal tumors due to neurofibromatosis generalisata, the use of the MRI contrast agent Gadolinium-DTPA resulted in a better differentiation especially of small lesions. High tumor contrast facilitated a safe localisation of the widespread disease using a fast imaging sequence (FLASH).  相似文献   
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Colour discrimination and visual contrast perception were investigated in 18 patients with Huntington's disease (HD) and in 18 age- and sex-matched healthy volunteers using the Farnsworth-Munsell 100 Hue test (FM) and stationary contrast targets. The mean total error score (MTES) and the partial scores for the “red-green” and the “blue-yellow” axes in the FM of the patients with HD were significantly elevated as compared to controls (MTES in HD: 113.0 ± 90.8; MTES in controls: 19.2 ± 8.8). The spatial contrast sensitivity in HD patients was normal. The colour perception dysfunction indicates that the visual system is affected in HD. The visual disorder may be related to an imbalance of certain neurotransmitters in the visual system of HD patients. Possible anatomical sites of the dysfunction responsible for colour discrimination abnormalities could be the retinal cone system and/or impaired parvocellular central visual pathways in HD.  相似文献   
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Jerosch  J.  Schulz  A. 《Trauma und Berufskrankheit》2007,9(3):S359-S364
Conservative treatment options for patients with degenerative arthritis have changed over the past decade. Subjective recommendations in the past were converted to evidence-based guidelines, especially due to the work of the European League Against Rheumatism (EULAR). In the first place are changes in patient lifestyle, which unfortunately take place only in the minority of patients. The use of symptomatic slow-acting drugs for osteoarthritis (SYSADOAs) as well as hyaluronic acid has increased over the last years. Both have been shown to be effective in evidence-based studies. Glucosamine and chondroitin sulfate have proved to be effective if they are used at an adequate dosage and for an appropriate time interval (at least 3 months). A special advantage seems to be that the use of nonsteroidal anti-inflammatory drugs (NSAIDs) can be reduced. The positive effect of hyaluronic acids has recently been demonstrated by a Cochrane study; hyaluronic acids have a positive effect in early and midstage degenerative arthritis. The use of hyaluronic acids can also reduce the need for NSAIDs.  相似文献   
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The uptake of radiolabeled somatostatin analogs by tumor cells through receptor-mediated internalization is a critical process for the in vivo targeting of tumoral somatostatin receptors. In the present study, the somatostatin receptor internalization induced by a variety of somatostatin analogs was measured with new immunocytochemical methods that allow characterization of trafficking of the somatostatin receptor subtype 2 (sst2), somatostatin receptor subtype 3 (sst3), and somatostatin receptor subtype 5 (sst5) in vitro at the protein level. METHODS: Human embryonic kidney 293 (HEK293) cells expressing the sst2, sst3, or the sst5 were used in a morphologic immunocytochemical internalization assay using specific sst2, sst3 and sst5 antibodies to qualitatively and quantitatively determine the capability of somatostatin agonists or antagonists to induce somatostatin receptor internalization. In addition, the internalization properties of a selection of these agonists have been compared and quantified in sst2-expressing CHO-K1 cells using an ELISA. RESULTS: Agonists with a high sst2-binding affinity were able to induce sst2 internalization in the HEK293 and CHO-K1 cell lines. New sst2 agonists, such as Y-DOTA-TATE, Y-DOTA-NOC, Lu-DOTA-BOC-ATE (where DOTA is 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid; TATE is [Tyr3, Thr8]-octreotide; NOC is [1-NaI3]-octreotide; and BOC-ATE is [BzThi3, Thr8]-octreotide), iodinated sugar-containing octreotide analogs, or BIM-23244 were considerably more potent in internalizing sst2 than was DTPA-octreotide (where DTPA is diethylenetriaminepentaacetic acid). Similarly, compounds with high sst3 affinity such as KE108 were able to induce sst3 internalization. In sst2- or sst3-expressing cell lines, agonist-induced receptor internalization was efficiently abolished by sst2- or sst3-selective antagonists, respectively. Antagonists alone had no effect on sst2 or sst3 internalization. We also showed that somatostatin-28 and somatostatin-14 can induce sst5 internalization. Unexpectedly, however, potent sst5 agonists such as KE108, BIM-23244, and L-817,818 were not able to induce sst5 internalization under the same conditions. CONCLUSION: Using sensitive and reproducible immunocytochemical methods, the ability of various somatostatin analogs to induce sst2, sst3, and sst5 internalization has been qualitatively and quantitatively determined. Whereas all agonists triggered sst2 and sst3 internalization, sst5 internalization was induced by natural somatostatin peptides but not by synthetic high-affinity sst5 agonists. Such assays will be of considerable help for the future characterization of ligands foreseen for nuclear medicine applications.  相似文献   
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Introduction  

Cattle are an important source of allergens in the working area of farmers. Asthma caused by cow allergens is a significant occupational problem. Yet in allergological testing, the results of in vivo and in vitro diagnostic tests are often inconsistent even in cases with clearly cattle-related symptoms.  相似文献   
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