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61.
Immunogenic peptides containing epitopes of the gp120 C4 and V3 regions from human immunodeficiency virus strains MN and EV91 have been studied by nuclear magnetic resonance and molecular modeling and used as immunogens in rhesus monkeys. The results, combined with those for other peptides, suggest a correlation between solution conformation and immunologic cross-reactivity.  相似文献   
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Although there has been significant research into gender regarding educational and workplace practices, there has been little awareness of gender differences as they pertain to software tools, such as spreadsheet applications, that try to support end users in problem-solving tasks. Although such software tools are intended to be gender agnostic, we believe that closer examination of this premise is warranted. Therefore, in this paper, we report an end-to-end investigation into gender differences with spreadsheet software. Our results showed gender differences in feature usage, feature-related confidence, and tinkering (playful exploration) with features. Then, drawing implications from these results, we designed and implemented features for our spreadsheet prototype that took the gender differences into account. The results of an evaluation on this prototype showed improvements for both males and females, and also decreased gender differences in some outcome measures, such as confidence. These results are encouraging, but also open new questions for investigation. We also discuss how our results compare to generalization studies performed with a variety of other software platforms and populations.  相似文献   
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This longitudinal study predicted marital outcome from communication skills gained from participation in the Prevention and Relationship Enhancement Program (PREP; H. J. Markman, S. L. Blumberg & S. M. Stanley, 1989; Stanley et al., 2001) by 39 women and 38 men. Results were in the expected direction for men but not for women. Men's pre- to posttest decrease in negative communication and increase in positive communication predicted decreased risk of marital distress onset in men. Women's pre- to posttest increase in positive communication, which was related to self-reported avoidance of problem solving, predicted an increased risk of male and female distress onset. Couples with men relatively high on premarital risk factors demonstrated a greater benefit from men's positive communication skills acquisition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Extraction and isoenzyme analysis of four isolates of Arthrobotrys including A. musiformis, A. robusta and A. conoides were conducted. Among the 14 enzymes studied by starch gel electrophoresis, using morpholine-citrate as gel/electrode buffer, the following nine enzymes showed interpretable banding patterns: alpha-esterase, fumarase, hexokinase, isocitrate dehydrogenase, leucine aminopeptidase, malate dehydrogenase, 6-phosphogluconate dehydrogenase, phosphoglucomutase and phosphoglucoisomerase. All isolates studied displayed typical isoenzyme phenotypes for each species. Two isolates of A. conoides differed in their alpha-isoesterase banding patterns, but no differences were observed for the other enzymes. The assay was satisfactory for enzyme extraction and resolution of Arthrobotrys and could be used in future taxonomic and genetic studies of this organism.  相似文献   
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RAS mutations occur frequently in acute myeloid leukaemia and myelodysplasia, suggesting a functional role for this oncogene in leukaemogenesis. We show here, for the first time, that both N-RAS and H-RAS can impair erythroid differentiation of erythroleukaemia cells induced with hexamethylene bisacetamide. Transformation by RAS allowed extended proliferation in the presence of inducer and also inhibited maturation as measured by impaired haemoglobinization and reduction in cell size. These data provide an interesting counterpoint to the effect of mutant RAS on monocytic cells, where it has a potentiating effect on differentiation and may indicate a causal link between the activation of RAS and erythroid lineage dysplasia in preleukaemia.  相似文献   
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