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JL Abkowitz KE Brown RW Wood NL Kovach SW Green NS Young 《Canadian Metallurgical Quarterly》1997,176(1):269-273
Parvovirus B19 (B19) DNA was detected by dot blot hybridization in sera from 5 (17%) of 30 human immunodeficiency virus (HIV)-infected patients with hematocrits (HCT) of < or =24 and 4 (31%) of 13 HRV-infected patients with HCT of < or =20, suggesting that B19 is a reasonably common cause of severe anemia in HIV infection. The anemia promptly remitted after immunoglobulin therapy in 3 of 4 treated patients. The presence of IgM to B19, the clinical circumstance in which anemia developed, and the marrow morphology were poor predictors of chronic B19 infection. DNA hybridization studies of sera from 191 HIV-infected and 117 HIV-seronegative homosexual males attending a clinic in the Seattle area revealed that 1 (0.5%) and 2 (2%) samples, respectively, from the 2 groups contained B19. However, when assayed by polymerase chain reaction (PCR), 5% of the serum samples from HIV-infected persons and 9% from uninfected persons contained B19, although each had an HCT of > or =40. The data argue that anemia results from chronic high-titer B19 infection. Although a negative PCR assay excludes this diagnosis, DNA hybridization may be the more specific serum test. 相似文献
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Memory in food-storing birds: from behaviour to brain 总被引:1,自引:0,他引:1
As a result of natural history studies, it has been hypothesized that food-storing birds may develop a special kind of memory to cope with the demand imposed by their food-storing behaviour (i.e. the ability to retrieve food from a wide variety of stores over varying amounts of time after storage). Recent studies on food-storing birds suggest that, at a relatively late stage in their development, the specific memories associated with food-storing behaviour can stimulate growth of the hippocampus, an area of the brain concerned with memory processing. 相似文献
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Discovery of selective, small-molecule inhibitors of RNA complexes--I. The Tat protein/TAR RNA complexes required for HIV-1 transcription 总被引:2,自引:0,他引:2
HY Mei DP Mack AA Galan NS Halim A Heldsinger JA Loo DW Moreland KA Sannes-Lowery L Sharmeen HN Truong AW Czarnik 《Canadian Metallurgical Quarterly》1997,5(6):1173-1184
We have developed a therapeutic program focusing on the inhibition of a human immunodeficiency virus-1 specific protein-RNA interaction. This program begins with a search for small organic molecules that would interfere with the binding of Tat protein to TAR RNA. The methodologies chosen to study the HIV-1 Tat-TAR interaction and inhibition include gel mobility shift assays, scintillation proximity assays, filtration assays, and mass spectrometry. These methods helped establish in vitro high-throughput screening assays which rapidly identified Tat-TAR inhibitors from our corporate compound library. Tat-activated reporter gene assays were then used to investigate the cellular activities of the Tat-TAR inhibitors. The cellular activity, selectivity, and toxicity data for select Tat-TAR inhibitors were determined. Evaluation of both the cellular data and the Tat-TAR inhibition results led to further testing in anti-HIV-1 infection assays. 相似文献
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AV Pugaev NS Bogomolova VV Bagdasarov KB Sirozhitdinov LN Vinogradova 《Canadian Metallurgical Quarterly》1997,(3):123-125
Pharmacokinetics was studied of kefsole administered by intravenous and endolymphatic routes to patients (n = 23) with acute pancreatitis. The studies made showed that intravenous route for the drug administration makes for a quicker entering of the antibiotic into the peritoneal exudate. Apart from these reasons, endolymphatic antibacterial therapy does not appear to avert the development of complications involving pus-formation/discharging in acute pancreatitis and does not seem to be essential in the complex of therapeutic measures to be applied for treating the above patients. 相似文献
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R. S. Chandel 《Materials and Manufacturing Processes》1998,13(2):181-188
The effect of submerged arc welding parameters on flux consumption was studied. It was found that the flux consumption increases with increasing current, voltage and electrode extension. For the same welding parameters the flux consumption is higher for straight polarity compared to reverse polarity. From the results it was concluded that any welding parameter that influences melting rate also influences flux consumption. 相似文献