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排序方式: 共有379条查询结果,搜索用时 15 毫秒
91.
Sintnicolaas K; van Marwijk Kooij M; van Prooijen HC; van Dijk BA; van Putten WL; Claas FH; Novotny VM; Brand A 《Blood》1995,85(3):824-828
We studied the value of leukocyte depletion of platelet transfusions for the prevention of secondary human leukocyte antigen (HLA)- alloimmunization in patients with a high-risk of prior immunization induced by pregnancies. Seventy-five female patients with hematologic malignancies (mostly acute leukemia) and a history of pregnancy were randomized to receive either standard random single-donor platelet transfusions (mean leukocytes, 430 x 10(6) per transfusion) or leukocyte-depleted random single-donor platelet transfusions. Leukocyte depletion to less than 5 x 10(6) leukocytes per platelet transfusion (mean leukocytes, 2 x 10(6) per transfusion) was achieved by filtration. Of the 62 evaluable patients, refractoriness to random donor platelets occurred in 41% (14 of 34) of the patients in the standard group and in 29% (8 of 28) of the patients in the filtered group (P = .52); anti-HLA antibodies developed in 43% (9 of 21) of individuals in the standard group and 44% (11 of 25) of cases in the filtered group. The time toward refractoriness and development of anti- HLA antibodies was similar for both groups. We conclude that leukocyte depletion of random single-donor platelet products to less than 5 x 10(6) per transfusion does not reduce the incidence of refractoriness to random donor platelet transfusion because of boostering of anti-HLA antibodies. 相似文献
92.
Liang Matthew H. Couto Maura C. M. Duarte Cátia C. M. Gall Victoria White Patience Naides Stanley Schumacher H. Ralph Hwang Andrew S. Holers V. Michael Deane Kevin D. Gupta Samar Ho I-Cheng Finckh Axel Kopec Jacek Choi Chan-Bum Sayre Eric C. 《Clinical rheumatology》2015,34(3):465-470
Clinical Rheumatology - Identifying persons with early rheumatoid arthritis (RA) is a major challenge. The role of the Internet in making decisions about seeking care has not been studied. We... 相似文献
93.
The incidence and consequences of HLA and non-HLA immunization were evaluated in 229 patients with aplastic thrombocytopenia. All patients were transfused with prestorage filtered red blood cells and platelets. On admission, 29 patients presented with HLA antibodies due to prior immunization by pregnancy and/or blood transfusions. Of the 200 patients showing no detectable HLA antibodies on admission, 164 could be evaluated. HLA antibodies developed in 2.7% (3 of 112) of the patients with a negative risk history of prior immunization. The occurrence of HLA antibodies in patients with a history of previous pregnancies or prior non-leukocyte-depleted blood transfusions (risk history positive) was 31% (16 of 52). Of the total of 48 patients who were or became alloimmunized, 92% (44 of 48) had a positive risk history. Ten patients with broad multispecific HLA antibodies with a panel reactivity (PRA) of greater than 70% required transfusions with HLA-matched platelets. Patients with HLA antibodies with lower PRA could be supported by random donor platelets. Two patients developed platelet-specific antibodies, causing transfusion refractoriness that necessitated selecting platelets by the absence of a platelet-specific antigen. Using prestorage leukocyte depletion of red cells and platelets with less than 5 x 10(6) residual leukocytes, 95% of the patients, including patients with a previous risk history or with HLA antibodies with low PRA, can be supported with random donor transfusions for the entire duration of their thrombocytopenic periods. 相似文献
94.
Prognostic implications of cytogenetic studies in an intensively treated group of children with acute lymphoblastic leukemia 总被引:2,自引:0,他引:2
Fletcher JA; Kimball VM; Lynch E; Donnelly M; Pavelka K; Gelber RD; Tantravahi R; Sallan SE 《Blood》1989,74(6):2130-2135
We assessed the prognostic significance of leukemia cell cytogenetics by analyzing bone marrow aspirates obtained at time of diagnosis in 165 children on a single protocol for acute lymphoblastic leukemia (ALL). These children were assigned to six mutually exclusive cytogenetic categories as follows: (1) hyperdiploid, with 50 or more chromosomes (n = 35); (2) hyperdiploid, with 47 to 49 chromosomes (n = 11); (3) diploid (n = 42); (4) pseudodiploid (n = 34); (5) hypodiploid (n = 9); and (6) insufficient data (n = 34). At a median follow-up of 5 years, there were no statistically significant differences between any of these cytogenetic categories in either event-free or overall survival. Those children with chromosomal translocations (n = 26) appeared to fare the same as those lacking translocations (n = 105). The absence of karyotypic prognostic significance was observed not only within the overall group, but also when the results were stratified by standard- risk and high-risk status. Of the specific structural chromosome changes that we studied, only the Philadelphia chromosome (Ph) appeared to confer a poor prognosis, although there were too few such cases to achieve statistical significance. Although we did not detect the event- free survival differences that have been described previously in hyperdiploid, hypodiploid, and pseudodiploid childhood ALL, our findings must be viewed as preliminary given the small number of children in some of the cytogenetic categories. We think that the prognostic implications of these cytogenetic features might have been nullified by improvements in therapy. 相似文献
95.
CD4 and CD8 T lymphocyte subsets, the late T cell activation marker,
HLA-DR, and serum interleukin-6 (IL-6) levels of 57 polymyalgia rheumatica
(PMR) patients were followed over 2 yr to investigate whether they could be
used to predict the safe withdrawal of steroid therapy. Cell phenotypes
were studied by flow cytometry and IL-6 levels by ELISA. %CD8 cells were
reduced below the normal range in PMR patients prior to steroid therapy. In
56% of patients, the %CD8 T lymphocytes failed to return to normal levels
when quiescent disease allowed cessation of steroid therapy. Activated CD8
T cells, as detected by HLA-DR positivity, were above the normal range at
the initiation of therapy and showed a negative correlation with %CD8 T
cells. The serum concentration of IL-6 fluctuated over 24 months, and the
correlation between IL-6 and erythrocyte sedimentation rate (ESR) seen
prior to treatment was not seen at later intervals. The %CD8 T cell and
serum IL-6 levels are not a good indicator of disease activity in PMR and
are, therefore, unable to predict the safe withdrawal of steroids.
相似文献
96.
Timothy E. Quan Robert M. Roman Benjamin J. Rudenga V. Michael Holers Joseph E. Craft 《Arthritis \u0026amp; Rheumatology》2010,62(6):1693-1701
Objective
Epstein‐Barr virus (EBV) infection has been linked to systemic lupus erythematosus (SLE), as demonstrated by the presence of increased seroprevalence and elevated viral loads, but the mechanism of this linkage has not been elucidated. Increased interferon‐α (IFNα) levels and signatures, which are associated with innate immune responses, have been found in patients with SLE. Plasmacytoid dendritic cells (PDCs) are innate immune cells that mediate viral immunity by producing large quantities of IFNα, but the role they play during infection with EBV remains unclear. To address this issue, we investigated the ability of EBV to promote IFNα production by PDCs in healthy subjects.Methods
Human PDCs were sorted and cultured in the presence of EBV, EBV‐encoded RNA, and EBV double‐stranded DNA. IFNα production by PDCs was measured by enzyme‐linked immunosorbent assay, with the activation of these cells measured by flow cytometry.Results
We found that EBV DNA and RNA promoted IFNα production by human PDCs through engagement of Toll‐like receptor 9 (TLR‐9) and TLR‐7, respectively, with the initial viral recognition by PDCs mediated by binding to class II major histocompatibility complex (MHC) molecules.Conclusion
These data demonstrate that class II MHC–specific engagement by virus, with subsequent viral nucleic acid recognition, mediates IFNα production by PDCs. Our results suggest that elevated levels of IFNα found in SLE patients may be a result of aberrantly controlled chronic viral infection.97.
D R Karp M L Carlisle A B Mobley T C Nichols N Oppenheimer-Marks R I Brezinschek V M Holers 《International immunology》1999,11(11):1791-1800
The ectoenzyme gamma-glutamyl transpeptidase (GGT) hydrolyzes glutathione (GSH), is required for the maintenance of normal intracellular GSH levels and modifies the activity of GSH-containing adducts. Previous data suggested that this enzyme was present on mitogen-activated T lymphocytes. However, the level of GGT protein expression on human mononuclear cell subsets has not been determined. A novel mAb to human GGT, 3A8, was developed. 3A8 was used to show that the expression of GGT is, in fact, highest on resting T cells that express markers of the memory phenotype, specifically CD45RO and decreased expression of CD45RB. The peripheral blood of patients with rheumatoid arthritis was found to have expanded numbers of T cells expressing levels of GGT up to 10-fold higher than controls. In addition, the CD4(+) T cell subset with the capacity to migrate across a human endothelial cell monolayer expresses high GGT levels. GGT expression was up-regulated on peripheral blood T cells following activation in vitro by either superantigen, phorbol ester, or IL-15, a stimulatory cytokine synthesized in rheumatoid synovium. Resting peripheral blood T cells that express GGT have higher levels of intracellular thiols than those that do not. These observations suggest that GGT may play an important role in the regulation of lymphocytes that are at a particular developmental stage. 相似文献
98.
Spondylolysis studied with computed tomography 总被引:10,自引:0,他引:10
99.
A case of dog bite where prompt immunization with antirabies vaccine alone proved inadequate in prevention of fatal rabies is reported to emphasize upon the need of concomitant passive immunization with either human rabies immune globulin or equine antiserum.KEY WORDS: Rabies, Active immunization, Passive immunization 相似文献
100.
Dose-dependent localization of TCDD in isolated centrilobular and periportal hepatocytes 总被引:3,自引:1,他引:2
Santostefano MJ; Richardson VM; Walker NJ; Blanton J; Lindros KO; Lucier GW; Alcasey SK; Birnbaum LS 《Toxicological sciences》1999,52(1):9-19
Dose-response relationships for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)
suggest a differential sensitivity of liver cell types to the induction of
cytochrome P450 gene expression, and that the induction of hepatic protein
CYP1A2 causes sequestration of TCDD. In addition, immunolocalization of
hepatic CYP1A1/1B1/1A2 proteins is not uniform after exposure to TCDD. The
mechanism for the regio-specific induction of hepatic P450s by TCDD is
unknown, but may involve the differential distribution of participants in
the AhR-mediated pathway and/or regional P450 isozymes, as well as,
non-uniform distribution/sequestration of TCDD. Therefore, this study
examined the effects of TCDD in unfractionated, centrilobular and
periportal hepatocytes isolated from female Sprague-Dawley rats acutely
exposed (3 days) to a single oral dose of 0.01-10.0 microg [3H]TCDD/kg. A
dose- dependent increase in concentration of TCDD was accompanied by a
dose- dependent increase in CYP1A1, CYP1A2, and CYP1B1 mRNA expression and
associated enzymes in all liver-cell populations. Centrilobular hepatocytes
showed a 2.7- to 4.5-fold higher concentration of TCDD as compared to the
periportal hepatocytes at doses up to 0.3 microg TCDD/kg. Centrilobular
hepatocytes also exhibited an elevated MROD activity as compared to the
periportal hepatocytes at doses up to 0.3 microg TCDD/kg. Furthermore,
centrilobular hepatocytes showed an elevated concentration of induced
CYP1A2 and CYP1B1 mRNA as compared to periportal hepatocytes within the
0.01- and 0.3-microg TCDD/kg- treatment groups. This is the first study to
demonstrate that a dose- dependent difference in distribution of TCDD
exists between centrilobular and periportal cells that might be related to
regional differences in P450 induction.
相似文献