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Forty-two cases of haemangiopericytoma were studied retrospectively using immunohistochemical staining with PC10, a monoclonal antibody to PCNA. The percentage of tumour cells with positive staining for PCNA was found to correlate well with histological grading. Clinical follow-up data were available in 25 adults and showed no known deaths in 11 cases with a low proportion (less than 14%) of positive cells. Out of 14 cases with a high number (greater than or equal to 14%) of positive cells, seven patients are known to have died, two had metastases, and in a further two there have been multiple recurrences of tumour. DNA flow cytometry was performed on 26 cases but this showed no correlation with PC10 staining or clinical outcome. Staining with PC10 may be of particular value in the identification of patients at greatest risk of rapid tumour metastasis and early death.  相似文献   
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Effects of alfentanil, preceded by lorazepam, on suppressionof haemodynamic and somatic responses to noxious stimuli wasstudied in patients undergoing CABG. Plasma concentration ofalfentanil, somatic and haemodynamic responses were measuredat loss of consciousness, tracheal intubation, sternotomy andduring multiple applications of electrocoagulation. Additionalalfentanil was administered i.v. to control unwanted responses.Study 1 (six patients): lorazepam 0.08 mg kg–1 by mouth1–2 h before operation, alfentanil priming infusion (60µg kg–1 min–1 for 10 min) followed by maintenanceinfusion (4.5 µg kg–1 min–1). With mean plasmaalfentanil 1178 (SEM 54) ng ml–1, two patients requiredsupplementary alfentanil to suppress somatic motor responses;one patient required nitroglycerin to control an increase inarterial pressure which was unresponsive to additional alfentanilfollowing sternotomy. Study 2 (13 patients): lorazepam 0.04mg kg–1 by mouth as premedication; one of three maintenanceinfusion rates of alfentanil: 5.4 (n=4), 6.6 (n=5), or 7.8 (n=4)µg kg–1 min–1, each preceded by a proportionalpriming infusion. With plasma alfentanil 2181 (62)ng ml–1,somatic motor responses requiring additional alfentanil occurredin nine patients; haemodynamic responses in four of seven patientstested could not be controlled by alfentanil. The highest plasmaconcentration of alfentanil to prevent response to a stimulusother than tracheal intubation was different between the twostudies (P<0.05). We conclude that alfentanil alone is insufficientto suppress haemodynamic and somatic motor responses to noxiousstimulation during CABG and that the role of premedication issignificant. *Department of Anesthesia, Bowman-Gray School of Medicine Winston-Salem,NC 27103, U.S.A. 2114 de Mayo Road, Del Mar, Ca. 92014, U.S.A.  相似文献   
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Eighty-three patients with rheumatoid arthritis (RA) were investigatedfor HLA-DQ and DR locus restriction fragment length polymorphisms(RFLP). Of the 83 patients, 61 (73%) possessed the DR4 alleleand within this group we have investigated the relative frequenciesof two DQ beta gene variants of DQw3, DQw7 and DQw8, one ofwhich we had previously found to be raised in Felty's syndrome.This analysis revealed a significantly higher frequency of DQw7containing haplotypes in DR4 positive rheumatoid patients (64%)than in DR-matched healthy controls (42%). Furthermore, thedistribution of DQw7 was biased towards those patients withgreater disability indicated by the HAQ score, more systemicdisease and higher titres of rheumatoid factor, suggesting thatDQw7 may contribute to disease expression. KEY WORDS: HLA system, Disease association, Rheumatoid factor  相似文献   
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