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Radiological gout manifestations are detectable in the early stage, but also especially in the chronic stage of gout. Whereas in the early stage only soft tissue mutations (bursitis inflammation) and light calcium deposits are usually discernible, chronic gout leads to asymmetrical, diverse forms of osseous destruction, favouring smaller joints, but also affecting larger ones, which are caused by the intra-articular and extra-articular deposit of tophus material, corresponding to the progression and degree of severity of the illness. Radiologically-detectable changes in other organs, such as the kidneys, will be addressed. The high number of, and to some extent very characteristic, osseous mutations are compared with those mutations which are very similar to the diagnoses of other syndromes affecting the joints. Specifically, problems in differentiating diagnosis of rheumatoid arthritis, arthritis psoriatica, chondrocalcinosis, and other diseases of the joints will receive special mention. Reference is also made to the extreme diagnostic difficulties resulting from the rare but nevertheless conceivable influence of gout on the spine or sacroiliac joints. The method of magnetic resonance imaging for gout shows a characteristic signal behaviour of the tophus material. It has been determined that, through magnetic resonance tomography, interosseous tophi can be detected earlier and in a more widespread manner than with the aid of native X-ray images, such that an increase in the use of this method is to be expected. 相似文献
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岩心PI值试验研究及应用 总被引:5,自引:0,他引:5
主要论述了在多功能采油化学用剂评价仪上进行的岩心PI值试验的步骤,现象及结论。重点考察了岩心PI值与渗透率、流量及注入截面面积的关系;平行管岩心复合PI值和其中单管岩心PI值的关系。 相似文献
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RA Wain GL Berdejo WN Delvalle RT Lyon LA Sanchez WD Suggs T Ohki E Lipsitz FJ Veith 《Canadian Metallurgical Quarterly》1999,29(1):100-7; discussion 107-9
PURPOSE: Arteriography is the diagnostic test of choice before lower extremity revascularization, because it is a means of pinpointing stenotic or occluded arteries and defining optimal sites for the origin and termination of bypass grafts. We evaluated whether a duplex ultrasound scan, used as an alternative to arteriography, could be used as a means of accurately predicting the proximal and distal anastomotic sites in patients requiring peripheral bypass grafts and, therefore, replace standard preoperative arteriography. METHODS: Forty-one patients who required infrainguinal bypass grafts underwent preoperative duplex arterial mapping (DAM). Based on these studies, an observer blinded to the operation performed predicted what operation the patient required and the best site for the proximal and distal anastomoses. These predictions were compared with the actual anastomotic sites chosen by the surgeon. RESULTS: Whether a femoropopliteal or an infrapopliteal bypass graft was required was predicted correctly by means of DAM in 37 patients (90%). In addition, both anastomotic sites in 18 of 20 patients (90%) who had femoropopliteal bypass grafts and 5 of 21 patients (24%) who had infrapopliteal procedures were correctly predicted by means of DAM. CONCLUSION: DAM is a reliable means of predicting whether patients will require femoropopliteal or infrapopliteal bypass grafts, and, when a patient requires a femoropopliteal bypass graft, the actual location of both anastomoses can also be accurately predicted. Therefore, DAM appears able to replace conventional preoperative arteriography in most patients found to require femoropopliteal reconstruction. Patients who are predicted by means of DAM to require crural or pedal bypass grafts should still undergo preoperative contrast studies to confirm these results and to more precisely locate the anastomotic sites. 相似文献
36.
Medicare is more than a payment system. As the nation's largest public payer of health care, Medicare dictates the way health care is delivered to elderly and disabled persons. Health care and health outcomes cannot make substantial improvements until the delivery system is changed. Medicare reform must support a coordinated health care delivery system (in place of hospital-centered, fragmented care) and proactive chronic disease management (in place of episodic, reactive care). Consumers, government, community-based agencies, employers, health plans, and others need to develop a shared understanding of what outcomes we want to obtain, what delivery system reforms are required, and how financing can support those reforms. 相似文献
37.
WK Vogel GL Peterson DJ Broderick VA Mosser MI Schimerlik 《Canadian Metallurgical Quarterly》1999,361(2):283-294
Double mutant cycles provide a method for analyzing the effects of a mutation at a defined position in the protein structure on the properties of an amino acid at a second site. This approach was used to map potential interactions between aspartates 69, 97, and 103 in the m2 muscarinic acetylcholine receptor transmembrane helices 2 and 3. Receptors containing single and double aspartate to asparagine mutants were expressed in Chinese hamster ovary cells and their effects on ligand binding, signal transduction, and thermal stability determined. Analysis of the double mutant cycles showed that the mutations had approximately additive effects on ligand binding, signal transduction, and thermal stability. Ligand binding and thermal inactivation results support the conclusion that aspartate-103 is the ligand amine counterion. Effector coupling properties of the mutant receptors showed that aspartate-103 was also required for signal transduction activity. The mutation of aspartate-69 to asparagine completely eliminated signal transduction by the agonists acetylcholine, carbachol, and pilocarpine but not oxotremorine M, which caused reduced but significant inhibition of adenylyl cyclase and stimulation of phospholipase C. In contrast, adenylyl cyclase stimulation by the asparagine-69 mutant was elicited only by acetylcholine and carbachol but not by oxotremorine M. The variation in agonist-dependent effector coupling properties provides evidence that the asparagine-69 mutant can exist in activated receptor states that are different from the wild-type m2 muscarinic receptor. 相似文献
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After a brief presentation of the development of free walking interpreted as learning dynamical equilibrium, the problem of sensory integration in the process of walking development is discussed. A critical review of the role of vision in the development of posturo-locomotor task is presented, along with recent test results on the development of the vestibular system. A final section presents the development of head stabilization and coordination as a necessary means to assist sensory integration. It is suggested that if sensory information is necessary to enhance posturo-locomotor skills, a good mastery of walking is in turn necessary to increase the efficiency of sensory integration. 相似文献
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