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101.
Is non-isotopic in situ hybridization finally coming of age? 总被引:9,自引:0,他引:9
102.
The biochemical and morphological differentiation of actinomycetes makes them academically and economically interesting. Their secondary metabolites provide the majority of medically and agriculturally important antibiotics (streptomycete genes may also be the primary source of clinically important antibiotic resistance); their complex morphological developmental cycle involves a series of changes from vegetative mycelial growth to spore formation. Recombinant DNA technology would add a powerful new dimension to the analysis of these various aspects of actinomycete biology and would also facilitate the development of industrial strains with increased antibiotic yield, or capable of making new antibiotics. For most of these purposes, cloning of genes within and between actinomycetes is required to study the expression of particular genes in genetic backgrounds defined by mutations of the characters under study. To achieve this, we have now developed a method for molecular cloning involving the transfer of genes between unrelated streptomycetes. 相似文献
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Interleukin-2 (IL-2), originally described as a growth factor required for sustained proliferation of T cells in vitro is a glycoprotein hormone of known structure which appears to be important for the generation of immune responses in vivo. As well as T lymphocytes, B lymphocytes and large granular lymphocytes with natural killer activity (NK cells) can also respond to IL-2. The action of IL-2 seemed to be limited specifically to lymphocytes, however, and the term 'T-lymphocytotrophic hormone' was used. Here we provide evidence that human monocytes display a substantially increased cytotoxic activity as a direct and rapid response to human recombinant IL-2 but not to human recombinant glycosylated interferon-gamma (IFN-gamma) or lipopolysaccharide. Our results reveal a previously unknown function of IL-2 and suggest its possible involvement in monocyte-T cell interactions. 相似文献
105.
Summary An analysis of allozyme data from numerous sets of related vertebrate andDrosophila species shows that species divergence does not generally seem to be accompanied by an overall increase or decrease in enzyme charge. The 2 significant results came from vertebrate inter-generic comparisons. 相似文献
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From an experiment in which corals are transplanted between two depths on a Panamanian coral reef, Baker infers that bleaching may sometimes help reef corals to survive environmental change. Although Baker's results hint at further mechanisms by which reef-building corals may acclimatize to changing light conditions, we do not consider that the evidence supports his inference. 相似文献
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Experimental annotation of the human genome using microarray technology 总被引:59,自引:0,他引:59
Shoemaker DD Schadt EE Armour CD He YD Garrett-Engele P McDonagh PD Loerch PM Leonardson A Lum PY Cavet G Wu LF Altschuler SJ Edwards S King J Tsang JS Schimmack G Schelter JM Koch J Ziman M Marton MJ Li B Cundiff P Ward T Castle J Krolewski M Meyer MR Mao M Burchard J Kidd MJ Dai H Phillips JW Linsley PS Stoughton R Scherer S Boguski MS 《Nature》2001,409(6822):922-927