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排序方式: 共有2041条查询结果,搜索用时 15 毫秒
31.
Phonocardiographic diagnosis of aortic ball variance 总被引:3,自引:0,他引:3
Fatty infiltration causing changes in the silastic poppet of the Model 1000 series Starr-Edwards aortic valve prostheses (ball variance) has been detected with increasing frequency and can result in sudden death. Phonocardiograms were recorded on 12 patients with ball variance confirmed by operation and of 31 controls. Ten of the 12 patients with ball variance were distinguished from the controls by an aortic opening sound (AO) less than half as intense as the aortic closure sound (AC) at the second right intercostal space (AO/AC ratio less than 0.5). Both AO and AC were decreased in two patients with ball variance, with the loss of the characteristic high frequency and amplitude of these sounds. The only patient having a diminished AO/AC ratio (0.42) without ball variance at reoperation had a clot extending over the aortic valve struts. The phonocardiographic findings have been the most reliable objective evidence of ball variance in patients with Starr-Edwards aortic prosthesis of the Model 1000 series. 相似文献
32.
We have recently found that antibodies to L-selectin, the homing receptor on neutrophils, are as effective as those to beta 2-integrin at blocking formyl peptide-stimulated aggregation. Therefore, we investigated the requirements for expression of L-selectin and beta 2- integrin on adjacent cells during aggregation. Fluorescence flow cytometry allowed characterization of aggregates on the basis of size and color, as well as antibody binding to these two adhesive molecules. Formyl peptide-stimulated aggregate formation was measured for individual populations fluorescently labeled red (LDS-751) or green (CD44-FITC), and interpopulation red-green cell conjugates. Blocking either the beta 2-integrin or L-selectin adhesive epitope with monoclonal antibody on individual cell populations resulted in an approximately 50% reduction in two-color aggregation as compared with that in unblocked samples. Shedding the L-selectin on a cell population by preincubation with complexes of lipopolysaccharide and its plasma membrane binding protein also decreased aggregation to a control population by approximately 50%. We examined the aggregation of neutrophils from patients genetically deficient in beta 2-integrin and clinically leukocyte adhesion deficient (LAD). LAD adhesion to normal neutrophils was dependent on the expression of L-selectin on LAD cells and beta 2-integrin on normal cells. Thus, the minimum requirement for adhesion between two mixed populations of neutrophils was that one population expressed the beta 2-integrin and the other expressed the L- selectin adhesive epitope. 相似文献
33.
R. M. TRÜEB P. BECKER-WEGERICH J. HAFNER B. WÜTHRICH G. BURG 《The British journal of dermatology》1995,133(1):109-114
Relapsing eosinophilic perimyositis is a rare entity. Only 11 cases have been reported in the literature. We describe a patient with relapsing myopathy, peripheral blood eosinophilia and cutaneous manifestations, who had histopathological features of eosinophilic perimysial inflammation. His disease responded to moderate doses of glucocorticosteroids, and pursued an apparently benign course. Serum levels of eosinophilic cationic protein correlate with disease activity, and may be helpful in monitoring treatment. The features of this case are compared with those of other hypereosinophilic syndromes. It appears to be part of the spectrum of eosinophilic myositis. 相似文献
34.
F M Russell J M Davis M J Whipp P H Janssen P B Ward J R Vyas M Starr S M Sawyer N Curtis 《Clinical infectious diseases》2001,33(1):129-130
We describe an immunocompetent adolescent who presented with exceptionally severe Bordetella holmesii infection, including previously undescribed manifestations. Sequelae included a severe restrictive lung defect due to pulmonary fibrosis. 相似文献
35.
Baron M Schieir O Hudson M Steele R Kolahi S Berkson L Couture F Fitzcharles MA Gagné M Garfield B Gutkowski A Kang H Kapusta M Ligier S Mathieu JP Ménard H Starr M Stein M Zummer M 《Arthritis and rheumatism》2008,59(3):382-390
OBJECTIVE: To assess the clinimetric properties of a new health-related quality of life (HRQOL) instrument, the World Health Organization Disability Assessment Schedule II (WHODAS II), in patients with early inflammatory arthritis. METHODS: Internal consistency as well as criterion, construct, and discriminative validity of the WHODAS II were assessed in 172 patients with early inflammatory arthritis who completed the WHODAS II, the Medical Outcomes Study Short Form 36 (SF-36), and other measures of disease severity, functioning, pain, depression, and resource use. Test-retest reliability of the WHODAS II was assessed by having a subset of 20 patients complete the WHODAS II a second time, 1 week after the first assessment. RESULTS: The WHODAS II had high internal consistency (Cronbach's alpha = 0.96 for patients working or in school and 0.93 for patients not working or in school). Test-retest intraclass correlation coefficients of the WHODAS II total score and subscales ranged from 0.82-0.96. The WHODAS II total score was strongly correlated with the SF-36 physical component score (Kendall's tau-b 0.51, P < 0.001) and moderately correlated with the SF-36 mental component score (tau-b 0.43, P < 0.001). WHODAS II correlations with disease outcomes ranged from Kendall's tau-b 0.15-0.55. The WHODAS II significantly differentiated between every aspect of disease severity assessed with the exception of measures of health resource use. CONCLUSION: The WHODAS II is a valid and reliable measure of HRQOL in cross-sectional studies of patients with early inflammatory arthritis. Research is still required to investigate potential item redundancy and determine its usefulness in longitudinal studies. 相似文献
36.
Remodeling of myocyte gap junctions in arrhythmogenic right ventricular cardiomyopathy due to a deletion in plakoglobin (Naxos disease). 总被引:8,自引:0,他引:8
Starr R Kaplan Joseph J Gard Nikos Protonotarios Adalena Tsatsopoulou Chara Spiliopoulou Aris Anastasakis Catherine Prost Squarcioni William J McKenna Gaetano Thiene Cristina Basso Nicole Brousse Guy Fontaine Jeffrey E Saffitz 《Heart rhythm》2004,1(1):3-11
OBJECTIVES: We tested the hypothesis that defective interactions between adhesion junctions and the cytoskeleton caused by the plakoglobin mutation in Naxos disease lead to remodeling of gap junctions and altered expression of the major gap junction protein, connexin43. BACKGROUND: Naxos disease, a recessive form of arrhythmogenic right ventricular cardiomyopathy, is associated with a high incidence of arrhythmias and sudden cardiac death. Naxos disease is caused by a mutation in plakoglobin, a protein that links cell-cell adhesion molecules to the cytoskeleton. METHODS: Myocardial expression of connexin43 and other intercellular junction proteins was characterized in 4 patients with Naxos disease. Immunohistochemistry was performed in all 4 patients, and immunoblotting and electron microscopy were performed in 1 patient who died in childhood before overt arrhythmogenic right ventricular cardiomyopathy had developed. RESULTS: Connexin43 expression at intercellular junctions was reduced significantly in both right and left ventricles in all patients with Naxos disease. Electron microscopy revealed smaller and fewer gap junctions interconnecting ventricular myocytes. Mutant plakoglobin was expressed but failed to localize normally at intercellular junctions. Localization of N-cadherin, alpha- and beta-catenins, plakophilin-2, desmoplakin-1, and desmocollin-2 at intercalated disks appeared normal. CONCLUSIONS: Remodeling of gap junctions occurs early in Naxos disease, presumably because of abnormal linkage between mechanical junctions and the cytoskeleton. Gap junction remodeling may produce a coupling defect which, combined with the subsequent development of pathologic changes in myocardium, could contribute to a highly arrhythmogenic substrate and enhance the risk of sudden death in Naxos disease. 相似文献
37.
38.
Borkowsky W Wara D Fenton T McNamara J Kang M Mofenson L McFarland E Cunningham C Duliege AM Francis D Bryson Y Burchett S Spector SA Frenkel LM Starr S Van Dyke R Jimenez E 《The Journal of infectious diseases》2000,181(3):890-896
Children of mothers infected with human immunodeficiency virus type 1 (HIV-1) were immunized at birth and at 1, 3, and 5 months with 1 of 3 doses of recombinant gp120 vaccines prepared from SF-2 or MN strains of HIV-1. A total of 126 children were not infected; 21 received adjuvant only. Vaccine recipients developed lymphoproliferative responses on >/=2 occasions, responding more often to homologous HIV-1 antigens than did adjuvant recipients (56% vs. 14%; P<.001). Responses were appreciated after 2 immunizations and were maintained for >84 weeks after the last immunization. An accelerated immunization schedule (birth, 2 weeks, 2 months, and 5 months) with the lowest dose of the SF-2 vaccine produced responses in all 11 vaccinees by 4 weeks. Responses to heterologous envelope antigens were also detected. Immune responses to vaccination are achievable at an age when some infection (perinatal or breast milk exposure related) may be prevented. 相似文献
39.