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排序方式: 共有844条查询结果,搜索用时 43 毫秒
1.
The effect of individual HLA-A and -B mismatches on the generation of cytotoxic T lymphocyte precursors 总被引:2,自引:0,他引:2
In order to study the correlation between HLA mismatches and the cytotoxic T lymphocyte precursor frequency, we used a limiting dilution analysis to determine the CTLp frequencies against individual mismatched HLA-A and -B alloantigens in 21 patients waiting for a renal transplant. Altogether, thirty-three mismatched HLA-A antigens and 55 HLA-B antigens were tested. The CTLp frequencies against mismatches of HLA-B locus antigens were found to be significantly higher than those against HLA-A antigens (P less than 0.002). This may explain why matching for HLA-B antigens is more important for a good renal allograft survival than matching for HLA-A antigens. 相似文献
2.
Frans H. J. Claas Janneke Langerak Lois Lolkes de Beer Jon J. van Rood 《Tissue antigens》1981,17(1):64-66
Preincubation of donor platelets with ticarcillin will prevent the reactivity of a platelet antibody against these platelets, whereas no influence was observed on antisera against HLA, 5A, 5b and ZWa. The implications for the mechanism of drug-induced antibodies with restricted specificity will be discussed. 相似文献
3.
Mulkerrin EC; Clark BA; Epstein FH 《QJM : monthly journal of the Association of Physicians》1997,90(6):411-415
We studied blood pressure and natriuretic responses to acute salt loading,
and the effect of non-steroidal anti-inflammatory agents on these
responses, in five healthy normotensive women aged 65 to 71 years. Five
women aged 25 to 31 years acted as controls. Intravenous saline loading,
with and without prior ingestion of ibuprofen, was 15 ml/kg/h for 3 h.
Baseline blood pressures were higher in the elderly. Saline infusion
without ibuprofen raised systolic blood pressure (SBP) by about 25 mmHg in
the older group only. Ibuprofen increased baseline SBP in the elderly (129
+/- 6 vs. 116 +/- 5 mmHg, p < 0.05). Saline loading after ibuprofen
again raised blood pressure by about 25 mmHg in the elderly only. The
elderly group showed markedly increased sodium excretion during saline
loading, but this was reduced by ibuprofen. Ibuprofen had no effect on SBP
or sodium excretion in controls. Ageing appears to increase susceptibility
to salt retention and hypertension from non-steroidal anti-inflammatory
agents.
相似文献
4.
B J Vermeer B Santerse B A Van De Kerckhove A A Schothorst F H Claas 《Transplantation》1988,45(3):607-610
The influence of ultraviolet (UVB) irradiation on the survival of H-2 class II-disparate skin grafts was studied in congenic mouse strains. Isolated skin was UVB irradiated in vitro at a dose of 40 mJ/cm2 from both sides to remove Ia immunogenicity. Immediately after irradiation the skin was transplanted onto the flank of allogeneic mice. When B10.AQR grafts were transplanted onto B10.T(6R) recipients, a significant prolongation of the survival time was observed, while 50% of the UVB-treated grafts were not rejected at all. However, in the opposite direction--i.e., B10.T(6R) grafts onto B10.AQR recipients, no significant prolongation of the survival was observed. To test whether this effect was due to a difference in susceptibility of the donor skin to UVB irradiation or to a different immune response in the recipients, (B10.T(6R) x B10.AQR) grafts were transplanted onto the parent strains. Similar results were obtained, in that UVB-treated grafts did not show a prolonged survival in B10.AQR recipients, whereas a significant prolongation (50% of the grafts survived more than 100 days) was observed in B10.T(6R) recipients. UVB-treated (B10.T(6R) x B10.AQR)F1 grafts were also transplanted onto (B10.T(6R) x C57B1/10)F1, (B10.AQR x C57B1/10)F1, (B10.T(6R) x Balb/c)F1 and (B10.AQR x Balb/c)F1 recipients--but in none of these combinations was a prolonged survival time observed. These data suggest that, in contrast to all in vitro experiments, the abrogation of the immune response by UVB treatment of the stimulator cells is, in vivo, not a general phenomenon. The genetic constitution of the responder mice seems to play an important role in determining whether or not an immune response takes place. 相似文献
5.
Acute thoracic aortic dissection has a high mortality if untreated, so the diagnosis must be rapidly made if mortality is to be lowered significantly. Multiple imaging techniques are often used. This retrospective study from 1988 to 1993 assesses the usefulness in diagnosis of chest X-rays, computed tomography (CT) scanning, aortography, magnetic resonance imaging (MRI), trans-thoracic (TTE) and trans-oesophageal (TOE) echocardiography. Forty-two patients with a final clinical diagnosis of dissection were studied. The diagnosis was confirmed in 16 (13 at surgery and three at autopsy). Three died with dissection given as the only cause for death. Chest X-ray abnormalities were seen in all 19 patients with surgery or death from dissection, with a widened mediastinum and/or dilated aorta being present in 17. In the group of 16 patients with surgery or autopsy proof, CT scans found dissections in 9 of 12 patients studied and correctly classified the type in only five. Aortography was performed in five, with accurate depiction of dissection and type in all. TTE found dissections in three of eight patients imaged by this method. MRI and TOE were performed each on two patients, with accurate depiction of dissection and type in each. Because of the relatively low sensitivity of CT scanning in defining aortic dissections Westmead Hospital is currently assessing the use of TOE as the prime imaging modality prior to surgical intervention. 相似文献
6.
In order to study the effect of blood transfusions on the donor-specific helper T cell repertoire, donor-specific interleukin 2-producing precursors (Th precursors [Thp]) were examined in 10 patients before and after transfusion. These patients were selected to be male, had received no previous transfusions or transplantation, and had no cytotoxic antibodies against MHC antigens in their serum. The limiting dilution curves were linear before as well as after transfusion, showing that only the cell under study was limiting. It was found that the transfusion donor-specific Thp frequencies increased significantly after transplantation in 10 of 10 patients (ratio: 1.5 to 7.1). In addition, the IL-2 production by individual clones tended to be higher after transfusion. In contrast, Thp frequencies against a third-party control showed a small increase in 4 and was unchanged in 6 patients. These data indicate that blood transfusions prime the donor-specific Th compartment. 相似文献
7.
Castillo S Reyes G Tejedor D Mozas P Suarez Y Lasuncion MA Cenarro A Civeira F Alonso R Mata P Pocovi M;Spanish Group of FH 《Human mutation》2002,20(6):477
Familial hypercholesterolemia is a genetic disorder caused by mutations in the LDL receptor gene. During a survey of mutations of LDL receptor gene in Spanish FH patients we found two mutations in the same allele: a missense N543H mutation in exon 11 and a 9bp inframe deletion (2393del9) located in exon 17. This double mutant allele was founded in 10 out of 458 unrelated patients: one homozygous FH [N543H+2393del9] + [N543H+2393del9], one compound heterozygote [N543H+2393del9] + [W-18X+E256K] and 8 heterozygotes. Flow cytometric analysis showed a defective LDL binding (20% of normal value) and internalization (23%) in lymphocytes from the homozygous patient; furthermore, studies of mitogen-stimulated lymphocytes demonstrated that the ability of LDL to support cell proliferation was impaired. Unexpectedly, not all carriers of the double mutant allele develop hypercholesterolemia and, furthermore, cholesterol-lowering treatment of the homozygous patient resulted in a 58% LDL cholesterol reduction. In conclusion, the phenotypic expression in the homozygous and heterozygous patients presented here, as well as the LDL-receptor residual activity, allowed the classification of this mutation as mild extending the group of mild mutations found at homozygosity. 相似文献
8.
9.
Hyperimmunized patients tend to accumulate on renal transplant waiting lists because their high level of sensitization leads to positive crossmatches with almost all potential organ donors. The origins of sensitization and the different efforts made to find cross-match negative donors for these patients are discussed. Special emphasis is given to a local strategy based on the determination of HLA-A and -B mismatches, against which the patient did not form allo-antibodies, the so-called acceptable mismatches. Kidney donor selection is based on compatibility with the patient's own HLA-antigens in combination with the acceptable HLA-A and -B antigens, and can be operated from a central organ-sharing office. The acceptable HLA mismatches are often identical with or include the non-inherited HLA class I antigens of the mother (non-inherited maternal antigens: NIMA). 相似文献
10.
Van Besouw Loonen Vaessen Balk Claas Weimar 《Clinical and experimental immunology》1998,111(3):548-554
Cellular immune processes may trigger the development of graft vascular disease (GVD). CD4 and CD8 cytotoxic T lymphocytes that infiltrate the allograft could play a role in the development of GVD. We studied the presence of in vivo primed or committed CTL (cCTL) and their avidity for donor HLA class I and class II antigens in graft-infiltrating lymphocyte cultures propagated from endomyocardial biopsies derived from patients with and without signs of GVD. The fraction of cCTL with high avidity for HLA class I or class II antigens was estimated by the addition of anti-CD8 or anti-CD4 MoAbs to the cytotoxic phase of the limiting dilution analysis. In the first year after transplantation no difference in the frequency of donor-specific class I cCTL between patients with and without GVD was found. Addition of anti-CD8 MoAb revealed that most cultures predominantly consisted of cCTL with low avidity for donor HLA class I antigens, irrespective of the development of GVD at 1 year after transplantation. However, in patients who did not develop GVD, the frequency of cCTL with donor HLA class II specificity was significantly higher than in patients who did develop GVD. The avidity for donor HLA class II antigens was comparable in both groups. A high frequency of donor-specific cCTL for HLA class II antigens seems to be a protective factor against the development of GVD. These cCTL might be cytotoxic for cells involved in GVD development, e.g. activated endothelium and smooth muscle cells of donor origin. 相似文献