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Due to some limitations of restriction fragment length polymorphism (RFLP) analysis in HLA-DR-DQ typing, we present a combined use of RFLP and polymerase chain reaction (PCR)-allele-specific oligonucleotide (ASO) typing. This scheme consists in selectively amplifying the few RFLP ill-defined genes (DR1/DR'Br' and DR4-Dw subsets) using PCR with allele specific primers to avoid cross-hybridization. 相似文献
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Y Leskinen JP Salenius T Lehtim?ki H Huhtala H Saha 《American journal of kidney diseases》2002,40(3):472-479
BACKGROUND: Knowledge of the prevalence of peripheral arterial disease (PAD) in patients with chronic renal failure (CRF) is limited because of a lack of uniformity in disease definition and recognition. Furthermore, little is known of the prevalence of medial arterial calcification (MAC) in patients with CRF. Our goal is to study the prevalence of PAD and MAC defined by ankle brachial index (ABI) or toe brachial index (TBI) measurements in a Finnish population of patients with CRF consisting of predialysis and dialysis patients, as well as renal transplant recipients. METHODS: We examined 136 patients with CRF and 59 control subjects. Fifty-nine of the patients with CRF had moderate to severe predialysis CRF, 36 patients were on dialysis treatment, and 41 were renal transplant recipients. Mean age of patients was 51.9 +/- 11.5 years, and 39 patients (29%) had diabetes. ABI and TBI were measured by means of photoplethysmography. The definition of PAD required an ABI value of 0.90 or less, a TBI value of 0.60 or less, or a previous positive lower-extremity angiogram result. ABI values of 1.3 or greater or incompressible arteries at ankle level indicated MAC. The presence of claudication was determined by an interview. RESULTS: Prevalences of PAD on this study were 22.0% in patients with predialysis CRF, 30.6% in patients on dialysis treatment, 14.6% in renal transplant recipients, and 1.7% in the control group (P = 0.001). Prevalences of MAC were 23.7%, 41.7%, 23.1%, and 3.4% (P < 0.001), respectively. Only 9 patients had claudication, and 6 of those patients had PAD. CONCLUSION: Both asymptomatic PAD and MAC are common in patients with CRF. Therefore, we recommend the use of both ABI and TBI measurements in the evaluation of PAD in patients with CRF. 相似文献
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T M Clay M R Howard J L Bidwell E A Bidwell P A Raymond J E Evans B A Bradley 《European journal of immunogenetics》1991,18(1-2):97-104
Thirty-seven DR4-positive patient-unrelated bone marrow donor pairs previously DR/DQ restriction fragment length polymorphism (RFLP) typed and tested in mixed lymphocyte culture (MLC), have been DR4-Dw subtyped retrospectively using sequence specific oligonucleotide probes. We found that DR4-Dw subtyping substantially increased the accuracy of pre-MLC matching and could potentially accelerate donor searches by avoiding unnecessary MLC tests on Dw-mismatched donors. 相似文献