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排序方式: 共有2132条查询结果,搜索用时 56 毫秒
131.
M Bouzyk SP Bryant C Evans S Guioli S Ford K Schmidt PN Goodfellow S Povey M Rebello S Rousseaux NK Spurr 《Canadian Metallurgical Quarterly》1997,5(5):299-307
OBJECTIVES: To determine concentrations of chondroitin sulphate (CS) and keratan sulphate (KS) epitopes, glycosaminoglycans (GAGs) and hyaluronan (HA) in knee synovial fluid (SF) from normal subjects and patients with osteoarthritis (OA) or rheumatoid arthritis (RA), to test whether these variables may be used as markers of the OA process. METHODS: OA was subdivided into large joint OA (LJOA), nodal generalised OA (NGOA), and OA with calcium pyrophosphate crystal deposition (CPA). Clinical assessment of inflammation (0-6) was undertaken on OA and RA knees. Knee SF was examined by enzyme linked immunosorbent assay for: CS epitopes, using monoclonal antibodies 3-B-3 and 7-D-4; KS epitope using monoclonal antibody 5-D-4; and HA, using biotinylated HA binding region of cartilage proteoglycan. Total sulphated GAGs were measured by dye binding with 1:9 dimethylmethylene blue. RESULTS: Increased SF 3-B-3 concentrations and 3-B-3/GAG ratio were found in OA, compared with RA or normal knees, with higher 3-B-3 and 3-B-3/GAG in LJOA and NGOA than in CPA. SF 7-D-4 and 7-D-4/GAG were reduced in RA, compared with normal and OA; SF 5-D-4 was reduced in OA compared with normal. GAG and HA concentrations were decreased in both OA and RA. No correlations with radiographic scores were observed, but SF 7-D-4 was lower in 'inflamed' compared with 'non-inflamed' RA and OA knees. In patients with bilateral samples there were strong correlations between right and left knees for all SF variables. CONCLUSIONS: Changed concentrations of SF CS and KS can be detected in OA with a profile that differs from that seen in RA. Clinical subgrouping and local joint inflammation may influence these measures, supporting different pathogenesis within OA subgroups and requirement for careful patient characterisation in SF studies. 相似文献
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I. M. Lerner G. I. Il’in 《Journal of Communications Technology and Electronics》2010,55(12):1385-1390
Transient processes at the output of an isolated oscillatory circuit caused by stepwise phase changes at the circuit input
are studied in the time and frequency domains. A mathematical model of this type of transient processes in the form of a narrowband
process is presented. Analytical expressions describing the behavior of the transient process in the time and frequency domains
are obtained. New features of this type of transient processes are revealed. 相似文献
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Directives and policies increasingly call for more integrated management of land and water. Frameworks such as integrated catchment management may address these calls, and yet their implementation requires decisions to be taken under conditions of extreme complexity and uncertainty. This paper summarises a participatory framework through which decision‐makers, experts and system modellers can collaboratively develop an integrated model to support such decisions. A feasibility study showed the potential of the framework. An operational version of the model, able to analyse the effects of 50 management options on 20 indicators, is estimated to require in the order of 225 man‐months from system modellers, alongside substantial inputs from stakeholders. The significant technical challenges confronting such an exercise may be overshadowed by the institutional challenges, including the fundamental question of whether organisations are truly committed. However, the reward for overcoming such challenges is the opportunity to achieve genuine improvements in the social, economic and environmental quality of our catchments. 相似文献
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Acute appendicitis caused by Ascaris lumbricoides is an uncommon variant of a common disease. We describe a case in which sonography was used for preoperative diagnosis of ascaris appendicitis. 相似文献