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排序方式: 共有2806条查询结果,搜索用时 31 毫秒
971.
972.
Melan-A/MART-1 is a melanoma differentiation antigen that is recognized by a high proportion of cytolytic T lymphocyte (CTL) clones derived from human leukocyte antigen (HLA)-A2+ melanoma patients. Whereas peptide Melan-A/ MART-1(27-35) was originally defined as the immunodominant CTL epitope, we have previously reported that peptide Melan-A/MART-1(26-35) was recognized more efficiently by the majority of tumor-reactive CTL clones. As demonstrated here, CTL populations generated from blood lymphocytes of either melanoma patients or healthy individuals after in vitro stimulation with peptide Melan-A/MART-1(26-35) killed specifically HLA-A2+ Melan-A+ allogeneic melanoma cells, thus suggesting their potential use in adoptive immunotherapy. We characterized the surface phenotype of the circulating CTL precursors (CTLp), which respond to in vitro stimulation with peptide Melan-A/MART-1(26-35). In melanoma patients, these CTLp predominantly expressed the CD45RO memory marker. In contrast, they were mainly, although not exclusively, found in the CD45RA subpopulation of CD8 T cells in healthy individuals. The demonstration that Melan-A/MART-1-specific CTLp in peripheral blood lymphocytes from HLA-A2+ patients with metastatic melanoma express a memory phenotype provides direct evidence that in vivo priming of this antigen may occur during tumor progression. 相似文献
973.
GJ Okano KL Rascati JP Wilson DD Remund JD Grabenstein DI Brixner 《Canadian Metallurgical Quarterly》1997,19(6):1433-45; discussion 1424-5
974.
JM Lawrence TL Moore TG Osborn G Nesher KL Madson MB Kinsella 《Canadian Metallurgical Quarterly》1993,22(4):265-274
Early studies showed few immunologic abnormalities in juvenile rheumatoid arthritis (JRA) patients. There were no specific laboratory markers useful for diagnosis and assessment of the course of disease in JRA. Previous work showed an association of antinuclear antibodies (ANA) with early-onset pauciarticular disease and iridocyclitis. Similarly, the presence of 19S immunoglobulin (Ig) M rheumatoid factors (RF) was associated with late-onset polyarticular disease in girls. More recent studies have detected many unique autoantibodies. Newer assays show 19S IgM RF in up to 35% of JRA patients, although still mainly in girls with late-onset polyarticular disease. Hidden 19S IgM RF can be shown in up to 75% of JRA patients using different procedures, primarily in those with active polyarticular-or pauciarticular-onset disease. Immune complexes have been detected in JRA patients by means of different techniques; their presence usually correlates with active disease. Studies on a specific ANA in JRA have shown no common extractable nuclear antigen, but antihistone antibodies have been found in up to 75% of cases, again mainly in those with pauciarticular onset and iritis. Finally, a variety of unusual immunologic proteins have also been detected, including anti-ocular, anti-cellular, anti-cardiolipin, anti-perinuclear factor, and anti-collagen antibodies. This review evaluates the significance of these antibodies that can now be found in JRA. 相似文献
975.
TL Williamson LI Bruijn Q Zhu KL Anderson SD Anderson JP Julien DW Cleveland 《Canadian Metallurgical Quarterly》1998,95(16):9631-9636
Mutations in superoxide dismutase 1 (SOD1), the only proven cause of amyotrophic lateral sclerosis (ALS), provoke disease through an unidentified toxic property. Neurofilament aggregates are pathologic hallmarks of both sporadic and SOD1-mediated familial ALS. By deleting NF-L, the major neurofilament subunit required for filament assembly, onset and progression of disease caused by familial ALS-linked SOD1 mutant G85R are significantly slowed, while selectivity of mutant-mediated toxicity for motor neurons is reduced. In NF-L-deleted animals, levels of the two remaining neurofilament subunits, NF-M and NF-H, are markedly reduced in axons but are elevated in motor neuron cell bodies. Thus, while neither perikaryal nor axonal neurofilaments are essential for SOD1-mediated disease, the absence of assembled neurofilaments both diminishes selective vulnerability and slows SOD1(G85R) mutant-mediated toxicity to motor neurons. 相似文献
976.
SA Husain J Nair W Holcomb JC Reid V Vargas SS Nair 《Canadian Metallurgical Quarterly》1998,155(12):1718-1719
OBJECTIVE: This was a study of posttraumatic stress symptoms in children and adolescents during siege conditions in Sarajevo. METHOD: Seven hundred ninety-one students aged 7-15 years were surveyed to assess symptoms of posttraumatic stress and level of deprivation. RESULTS: Girls reported more stress than boys. Loss of family members and deprivation of basic needs were associated with more symptoms. CONCLUSIONS: Personal experiences of siege are related to increased stress. 相似文献
977.
978.
Cormack I.G. Reid D.T. Wadsworth W.J. Knight J.C. Russell P.St.J. 《Electronics letters》2002,38(4):167-169
Results from a study in which Raman-shifted outputs were observed from photonic crystal fibres pumped by 800 nm femtosecond pulses are reported. Under optimum conditions, a spectral shift to wavelengths of 1260 nm was recorded 相似文献
979.
980.