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Stephanie Constant Mona Zain Jeff West Theresa Pasqualini Patricia Ranney Kim Bottomly 《European journal of immunology》1994,24(5):1073-1079
Primed and unprimed lymphocytes are usually classified as separate subsets of cells, based on phenotypic and functional distinctions. In the case of CD4+ T lymphocytes, primed cells are thought to proliferate more vigorously, quickly and easily, and to release a different profile of cytokines, than their naive equivalent. However, most of these data were obtained from studies in which populations of lymphocytes were compared before and after antigenic stimulation, and therefore did not distinguish between the effects resulting from the clonal expansion of specific precursor cells within such populations and those due to cell differentiation per se. We have investigated the contribution of precursor cell frequency to some of the functional changes observed in populations of CD4+ T cells following antigenic stimulation, using approaches in which antigen-specific precursor frequencies are high in both primary and secondary stimulations: mixed leukocyte reaction responses and cells from αβ T cell receptor transgenic mice. Our data suggest that when equivalent numbers of antigen-specific naive and previously primed CD4+ responder T cells are compared, there is no difference in their potency to proliferate but only the previously activated subset can generate cytokines such as interferon-γ. 相似文献
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M Salim S Rehman E M Sajdel-Sulkowska W G Chou R E Majocha C A Marotta S B Zain 《Neurobiology of aging》1988,9(2):163-171
Studies were undertaken to assess the extent to which messenger RNA prepared from the postmortem Alzheimer's disease (AD) brain can be used for the successful preparation of a recombinant cDNA library. Initial experiments focused on the glial-specific marker glial fibrillary acidic protein (GFAP) since GFAP expression appeared to be a model for further studies on mRNAs that may continue to be expressed at high levels in the vicinity of lesioned sites in the AD brain. An AD cDNA library, prepared in the lambda gt11 expression vector system contained GFAP-specific recombinants. One of these was sequenced and the insert was shown to exhibit 88% homology with the similar sequence from mouse GFAP. As established by Northern blots, the size of the GFAP mRNA prepared from the routinely acquired postmortem AD cortex, approximately 2.7 kb, was the same as from a neurologically normal control brain. These results agree with earlier studies on GFAP mRNA from fresh mouse brain. The results demonstrate that in the postmortem AD brain, astroglial-specific mRNA remains sufficiently stable for molecular genetic analysis and may serve as a useful model for examining the genetic expression of mRNAs that may be related to the molecular pathogenesis and the etiology of AD. 相似文献
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Allegretti Jessica R. Kassam Zain Chan Walter W. 《Digestive diseases and sciences》2018,63(1):193-197
Digestive Diseases and Sciences - Fecal microbiota transplantation (FMT) is safe and effective for recurrent Clostridium difficile infection (rCDI) and often involves terminal ileal (TI) stool... 相似文献
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AbstractMycotoxins pose severe health hazards in animals, humans, and poultry birds. More than 400 chemically different mycotoxins have been identified to date. Twenty-five percent of world’s crops are potentially contaminated with mycotoxins. Luckily, nature has provided the ruminants a unique property of inactivating and detoxifying most of the mycotoxins with the help of microflora and microfauna present within their ruminal fluid; however, unfortunately avian species lack such ability putting them at high risk to the deleterious effects of mycotoxins. This review elaborates different strategies for diagnosis, prevention and control of mycotoxins. 相似文献
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Zain Chagla Natasha Aleksova Jaclyn Quirt Joel Emery Christian Kraeker Shariq Haider 《The Canadian Journal of Infectious Diseases & Medical Microbiology》2014,25(4):225-226
Melioidosis is an infection endemic to Southeast Asia and Northern Australia, and is associated with significant morbidity and mortality. The present report describes a case of chronic melioidosis in a returning traveller from the Philippines. Clinical suspicion of this illness is warranted in individuals with a history of travel to endemic regions. Safety in handling clinical specimens is paramount because laboratory transmission has been described. 相似文献
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