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991.
In an earlier study we demonstrated that Concanavalin-A stimulated bovine T cell supernatants inhibited the growth of Cowdria ruminantium in bovine endothelial cells in vitro. An investigation was conducted to identify the cytokines which were responsible for this growth inhibition. Addition of antiserum against bovine interferon gamma (IFN gamma) reproducibly neutralized the inhibitory effect of the T cell supernatants, whereas addition of antisera against bovine tumor necrosis factor alpha (TNF alpha) had no effect. The inhibitory effect of IFN gamma on C. ruminantium growth was not mediated by the production of nitric oxide as there was no detectable difference in nitric oxide levels in cultures that were supplemented with T cell supernatants compared with those that were not. The IFN gamma mediated anti-C. ruminantium effect highlights the importance of cell mediated immune responses in control of these infections and in particular incriminates the protective role of T cells, or cells that secrete IFN gamma. 相似文献
992.
A case of parotid lipomatosis is reported, and the literature is reviewed. This rare condition presents as a slow growing parotid mass, which may be diagnosed preoperatively using computed tomography or magnetic resonance imaging. Long-term clinical follow-up is important because apparently complete surgical excision may be complicated by recurrence. 相似文献
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994.
JP Woessner AJ Molendijk P van Egmond FM Klis UW Goodenough MA Haring 《Canadian Metallurgical Quarterly》1994,26(3):947-960
Based on our previous work demonstrating that (SerPro)x epitopes are common to extensin-like cell wall proteins in Chlamydomonas' reinhardtii, we looked for similar proteins in the distantly related species C. eugametos. Using a polyclonal antiserum against a (SerPro)10 oligopeptide, we found distinct sets of stage-specific polypeptides immunoprecipitated from in vitro translations of C. eugametos RNA. Screening of a C. eugametos cDNA expression library with the antiserum led to the isolation of a cDNA (WP6) encoding a (SerPro)x-rich multidomain wall protein. Analysis of a similarly selected cDNA (VSP-3) from a C. reinhardtii cDNA expression library revealed that it also coded for a (SerPro)x-rich multidomain wall protein. The C-terminal rod domains of VSP-3 and WP6 are highly homologous, while the N-terminal domains are dissimilar; however, the N-terminal domain of VSP-3 is homologous to the globular domain of a cell wall protein from Volvox carteri. Exon shuffling might be responsible for this example of domain conservation over 350 million years of volvocalean cell wall protein evolution. 相似文献
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998.
S Ferry T Pritchard J Keenan P Croft AJ Silman 《Canadian Metallurgical Quarterly》1998,25(8):1616-1619
OBJECTIVE: To determine whether, in individuals in the general population with hand symptoms, there is a greater level of disability in those with objective evidence of delayed nerve conduction. METHODS: A 19 item disability schedule relevant to hand function was developed for this survey. Subjects included 71 individual respondents to a random population survey who reported pain, tingling, numbness, or loss of sensation in the hands during an interview and who agreed to have nerve conduction studies. They were divided into those with (10) and without (61) delayed median nerve conduction. RESULTS: Those with delayed conduction were more likely to report disability for 14 of the 19 items assessed. Half those with delayed conduction reported disability in 7 or more items, compared with 18% of those with normal conduction (chi-squared = 7.49, p = 0.006). Disability items that showed the greatest disparity between the 2 groups were those that relied on hand, although not specifically fine hand, movements. CONCLUSION: Individuals with hand symptoms in the general population who have objective evidence of delayed nerve conduction have a greater degree of self-reported disability than those with normal conduction. 相似文献
999.
Electroenzymatic reduction of NAD+ to NADH for subsequent use in enzymatic synthesis has been carried out at carbon electrodes bearing lipoamide dehydrogenase (LiDH) immobilized under a Nafion film. The self-mediated electron transfer was made possible by an excess of flavin adenine dinucleotide (FAD) entrapped together with LiDH. Results were compared to those obtained with a similar electrode containing both LiDH and a polymeric form of FAD (pFAD) prepared by anodic polymerization of FAD. 相似文献
1000.