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排序方式: 共有940条查询结果,搜索用时 46 毫秒
931.
To assess the effect of exercise protocol and number of monitoring leads on the ability of the ST/HR slope and delta ST/HR index to identify three-vessel coronary artery disease, the exercise ECGs of 50 patients who had coronary arteriography were reviewed. Test performance of the ST/HR slope using the Cornell exercise protocol with 13 leads was compared with performance obtained from the standard 12 leads and from sets of only 3 leads, as well as with test outcome using Bruce protocol equivalent stages with multiple-lead sets. ST/HR slopes could be calculated in 100% of patients using data from the Cornell protocol, but in only 80% of patients using the Bruce protocol with 13 leads (chi 2 = 8.1, p less than 0.005) and 54% of patients using the Bruce protocol with 3 leads (chi 2 = 21.0, p less than 0.001). With the Cornell protocol and 13 leads, an ST/HR slope partition of 6.0 microV/bpm identified three-vessel disease with a sensitivity of 96%, specificity of 58%, and overall test accuracy of 76%. At matched specificity, the Bruce protocol 13-lead ST/HR slope partition of 5.0 microV/bpm had a sensitivity of only 48% and overall test accuracy of 53% for three-vessel disease in those patients with calculable test outcomes (each p less than 0.01). Receiver operating characteristic curve analysis confirmed the superior performance of data acquired with the Cornell protocol and demonstrated no significant loss of Cornell ST/HR slope performance calculated from fewer monitored leads. Performance of the delta ST/HR index was similar with 3 leads and with 13 leads.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
932.
Characterization of fibrinogen Milano I: amino acid exchange gamma 330 Asp----Val impairs fibrin polymerization 总被引:1,自引:0,他引:1
An abnormal fibrinogen was found in two asymptomatic members (father and daughter) of the same family, originating from northern Italy. Routine coagulation studies revealed prolonged thrombin and reptilase clotting times. Plasma fibrinogen levels, as determined by a functional assay, were markedly diminished, whereas the heat precipitation method indicated normal fibrinogen values. On the basis of these findings, a tentative diagnosis of dysfibrinogenemia was made, and according to the accepted nomenclature, this fibrinogen variant was called "fibrinogen Milano l." The time course of fibrinopeptide A and B release from fibrinogen Milano l was normal, but the aggregation of fibrin monomers was delayed. Two-dimensional electrophoresis of reduced variant fibrinogen chains showed a defective gamma-chain with increased cathodic mobility. An abnormal electrophoretic mobility was observed also for the gamma-chain remnants of fibrinogen fragments D1 and D2 derived from fibrinogen Milano l, whereas the charge anomaly was lost after a further digestion by plasmin to D3, suggesting that the structure abnormality of this variant is situated in the region gamma 303-356. An abnormal peptide was isolated after cyanogen bromide cleavage of intact fibrinogen Milano l. This fragment spans from position gamma 311 to gamma 336. Amino acid analysis of the abnormal peptide showed the presence of valine and a diminished content of aspartic acid. Sequence analysis demonstrated an amino acid exchange Asp----Val in the gamma-chain at position 330. 相似文献
933.
Hassan HJ; Orlando M; Leonardi A; Chelucci C; Guerriero R; Mannucci PM; Mariani G; Peschle C 《Blood》1985,65(2):441-443
This study includes 47 normal subjects and 25 hemophilia B patients without inhibitor(s), showing different factor IX coagulant activity and antigen levels. Genomic DNA, digested with various restriction endonucleases, was hybridized with two different factor IX probes, ie, the cDNA and the subgenomic probe for the intragenic TaqI polymorphic site. cDNA restriction patterns suggest absence of gross rearrangements and/or deletions in all hemophilic patients. The frequency of the X chromosome bearing the TaqI polymorphic site is 0.32 +/- 0.09 in hemophilic subjects v 0.36 +/- 0.06 in normal control subjects, the latter value being comparable to that reported for the normal British population. No association between this polymorphism and hemophilia B variants has been observed, thus indicating that a wide spectrum of mutations underlies this blood-clotting disorder and particularly each of its variants. 相似文献
934.
Parker PM; Chao N; Nademanee A; O'Donnell MR; Schmidt GM; Snyder DS; Stein AS; Smith EP; Molina A; Stepan DE 《Blood》1995,86(9):3604-3609
Thalidomide has been reported to be an effective agent for treatment of chronic graft-versus-host disease (CGVHD). To determine the efficacy of this agent in patients with refractory CGVHD a total of 80 patients who failed to respond to prednisone (PSE) or PSE and cyclosporine (CSA) were treated with thalidomide. Sixteen patients (20%) had a sustained response, 9 with a complete remission and 7 with a partial response. Twenty-nine patients (36%) had thalidomide discontinued because of side effects, which included sedation, constipation, neuritis, skin rash, and neutropenia. Side effects were reversible with drug discontinuation except for mild residual neuritis in one case. Rashes and neutropenia have not previously been reported as thalidomide side effects when used for CGVHD treatment. We conclude thalidomide is immunosuppressive and active in the treatment of CGVHD. A high incidence of reversible side effects limited dose intensity and reduced the number of patients who could benefit from treatment. 相似文献
935.
Rh E/e genotyping by allele-specific primer amplification 总被引:1,自引:0,他引:1
Faas BH; Simsek S; Bleeker PM; Overbeeke MA; Cuijpers HT; von dem Borne AE; van der Schoot CE 《Blood》1995,85(3):829-832
It has been shown that the Rhesus (Rh) blood group antigens are encoded by two homologous genes: the Rh D gene and the Rh CcEe gene. The Rh CcEe gene encodes different peptides: the Rh C, c, E, and e polypeptides. Only one nucleotide difference has been found between the alleles encoding the Rh E and the Rh e antigen polypeptides. It is a C-- >G transition at nucleotide position 676, which leads to an amino acid substitution from proline to alanine in the Rh e-carrying polypeptide. Here we present an allele-specific primer amplification (ASPA) method to determine the Rh E and Rh e genotypes. In one polymerase chain reaction, the sense primer had a 3'-end nucleotide specific for the cytosine at position 676 of the Rh E allele. In another reaction, a sense primer was used with a 3'-end nucleotide specific for the guanine at position 676 of the Rh e allele and the Rh D gene, whereas the antisense primer had a 3'-end nucleotide specific for the adenine at position 787 of the Rh CcEe gene. We tested DNA samples from 158 normal donors (including non-Caucasian donors and donors with rare Rh phenotypes) in these assays. There was full concordance with the results of serologic Rh E/e phenotyping. Thus, we may conclude that the ASPA approach leads to a simple and reliable method to determine the Rh E/e genotype. This can be useful in Rh E/e genotyping of fetuses and/or in cases in which no red blood cells are available for serotyping. Moreover, our results confirm the proposed association between the cytosine/guanine polymorphism at position 676 and the Rh E/e phenotype. 相似文献
936.
Fibrin glue: the perfect operative sealant? 总被引:12,自引:0,他引:12
937.
BACKGROUND: Because the Rh antigens E (Rh3) and c (Rh4) are relatively immunogenic, it has been suggested that R1R1 (E-, c-) patients who present with anti-E alone receive prophylactic c- (Rh: -4) red cell transfusions. STUDY DESIGN AND METHODS: To determine the utility of this approach, the transfusion records of 100 consecutive R1R1 patients with anti-E identified over a 6-year period were reviewed. RESULTS: Thirty-two (32%) had anti-c concurrent with anti-E. Twenty-seven of the 68 patients who presented with anti-E alone received random (i.e., not typed for c [Rh4]) red cell transfusions. Five (18.5%) of the 27 subsequently developed anti-c 13 to 193 days (mean, 50) after transfusion of 2 to 14 (mean, 8) red cell units. None of the five had clinical evidence of hemolysis that could be attributed to a delayed hemolytic transfusion reaction. Twenty-two (81.5%) of the 27 failed to develop anti-c even after transfusion of 1 to 41 (mean, 9; median, 7) red cell units. CONCLUSION: The overall rate of immunization to c (Rh4) antigen in R1R1 patients with anti-E was 37 percent. Production of anti- c following transfusion to R1R1 patients with anti-E occurred in 18.5 percent of the cases in this series, which could have been avoided by the prophylactic use of R1R1 (E-, c-) blood for transfusion. The prophylactic use of c- (Rh: -4) blood in this patient population may be justified by the high immunization rate and the potential risk of delayed hemolytic transfusion reaction. 相似文献
938.
PM Mannucci ; K Schimpf ; T Abe ; LM Aledort ; K Anderle ; DB Brettler ; MW Hilgartner ; PB Kernoff ; M Kunschak ; CW McMillan ; et al. 《Transfusion》1992,32(2):134-138
A multicenter prospective study was carried out to evaluate whether a vapor-heated factor VIII concentrate transmitted blood-borne viral infections over a surveillance period of 15 months. Thirty-five patients with hemophilia and von Willebrand disease who had never received any blood components were treated. Twenty-eight were analyzed and found not to have non-A, non-B hepatitis. Sera from 20 of these 28 patients were also tested for the antibody to the hepatitis C virus. None had sero-converted during the follow-up period. None of the patients analyzed developed markers of the hepatitis B virus (n = 17) or the human immunodeficiency virus (n = 31). This vapor-heated factor VIII concentrate carries a low risk of transmitting hepatitis and human immunodeficiency virus infection. 相似文献
939.
940.
Rosaria Gesuita PhD Ivana Rabbone MD Vittorio Marconi MD Luisa De Sanctis MD Monica Marino RD Valentina Tiberi MD Antonio Iannilli MD Davide Tinti MD Lucia Favella PM Carlo Giorda MD Flavia Carle PhD Valentino Cherubini MD 《Diabetes, obesity & metabolism》2023,25(6):1698-1703