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Recent data indicate that rheumatoid arthritis is more often systemic, progressive, and disabling than benign, and that it reduces life expectancy. The new evidence argues for a dramatic alteration in pharmacologic management. If several months of rest, exercise, and anti-inflammatory therapy are ineffectual, aggressive treatment with disease-modifying antirheumatic and immunosuppressive agents may be in order. 相似文献
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Clonality in T-cell malignancy was investigated using T-cell receptor (TcR) V beta 1-20 family primers and polymerase chain reaction amplification (PCR) of cDNA prepared from tissue biopsies and blood involved with tumour. Secondary PCR amplification of the VDJ joints of primary PCR products was performed to distinguish clonal from polyclonal products, and clonal V beta gene products were confirmed by direct PCR sequencing in the majority of cases. In eight T-cell malignancies including T-cell acute lymphoblastic leukaemia (T-ALL) and T-cell chronic lymphocytic leukaemia (T-CLL) shown to be clonal by Southern blot analysis, one or two primary PCR products were identified and shown to be clonal. In five cases of peripheral T-cell lymphoma (PTCL) all V beta 1-20 families were identified after primary PCR amplification, and clonal products were identified in two cases after secondary amplification; TcR V beta clonal families could not be demonstrated in the remaining three cases. These data were in agreement with previous Southern blot analysis of these cases, and confirmed the presence of reactive T cells in PTCL as well as providing further evidence for the genotypic heterogeneity of this entity. In the remaining case, a blood lymphocytosis, primary PCR amplification produced predominant TcR V beta 6 and V beta 12 family products, of which the V beta 6 family proved clonal after secondary PCR amplification. There was no evidence for overrepresentation of TCR V beta families by the tumour populations in this study, furthermore the data confirm the involvement of reactive cells in T-cell malignancy and the genetic heterogeneity of PTCL. 相似文献
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Sellars M.P. Greaves S.D. Porter J. Crosby D.B. Freeman B.R. 《Electronics letters》2003,39(7):624-625
A precoding technique for pre-equalising contention bursts in a slotted-ALOHA access request scheme, for use in single-carrier broadband fixed wireless access (FWA) networks is presented. Multipath channel distortion is compensated for at the transmitter, so that the contention burst arrives undistorted at the receiver. 相似文献
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A non-invasive headspace analysis method to measure rate and amount of oxygen uptake in oxygen-scavenging polymers is presented. Oxygen uptake data for metal-catalyzed poly(1,4-butadiene) at 30 °C are provided to illustrate the method. These data were obtained by measuring oxygen headspace concentration above the scavenging polymer with an OxySense® 200T non-invasive oxygen sensor, and, for comparison, oxygen uptake was measured with an analytical balance. Excellent agreement was observed between these two independent experiments. 相似文献
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SS Burkhart SP Fischer WM Nottage JC Esch FA Barber D Doctor J Ferrier 《Canadian Metallurgical Quarterly》1996,12(6):704-708
The primary purpose of this investigation was to compare tissue fixation security by simple sutures versus mattress sutures in transosseous rotator cuff repair. These two repair techniques were each performed in 17 human cadaver shoulders, with two bone tunnels being used for the repair by two simple sutures and two other bone tunnels being used for the repair by one mattress suture. The repairs were loaded to failure in a servohydraulic materials test system. Rotator cuff repair by simple sutures was found to be significantly stronger than repair by mattress sutures (P = .0007). The average ultimate load to failure for the simple suture construct (189.62 N) was 39.72% greater than that for the mattress suture construct (135.71 N). Most of the failures occurred by suture breakage at the knot. Load-sharing by multiple suture tails and multiple knots in the simple suture configuration likely contributed to its superior strength characteristics compared with the mattress suture configuration. 相似文献