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D. L. Smalley 《Cellular and molecular life sciences : CMLS》1982,38(12):1483-1484
Summary 7 strains ofPseudomonas paucimobilis and 7 strains ofFlavobacterium multivorum (formerly groups IIK biotype 1 and biotype 2, respectively) showed endotoxin-like activity in vitro by the limulus amoebocyte lysate test. 相似文献
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The mammary gland undergoes major developmental changes during puberty and pregnancy. It is thought that stem cells drive mammary gland development during puberty and are responsible for tissue maintenance as well as the major growth and remodelling that occurs with every pregnancy. The use of sophisticated cell separation procedures has facilitated the prospective isolation of mammary epithelial stem and differentiated cell subpopulations from the mouse mammary gland, while studies of primary human breast cancers have described sub-populations of tumourigenic cells capable of initiating tumour growth in immuno-compromised mice. These potential tumour 'stem cells' constitute an important therapeutic target population with respect to cancer therapy, as these are likely to be the cells which maintain tumour growth. Understanding the origin of these cells, their relationship to breast cancer subtypes, and how and why they differ from normal breast stem cells will lead to a revolution in tumour understanding, treatment and prevention. (Part of a Multi-author Review). 相似文献
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Space geodetic evidence for rapid strain rates in the New Madrid seismic zone of central USA 总被引:1,自引:0,他引:1
In the winter of 1811-1812, near the town of New Madrid in the central United States and more than 2,000 km from the nearest plate boundary, three earthquakes within three months shook the entire eastern half of the country and liquefied the ground over distances far greater than any historic earthquake in North America. The origin and modern significance of these earthquakes, however, is highly contentious. Geological evidence demonstrates that liquefaction due to strong ground shaking, similar in scale to that generated by the New Madrid earthquakes, has occurred at least three and possibly four times in the past 2,000 years (refs 4-6), consistent with recurrence statistics derived from regional seismicity. Here we show direct evidence for rapid strain rates in the area determined from a continuously operated global positioning system (GPS) network. Rates of strain are of the order of 10(-7) per year, comparable in magnitude to those across active plate boundaries, and are consistent with known active faults within the region. These results have significant implications for the definition of seismic hazard and for processes that drive intraplate seismicity. 相似文献
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Lemay SG Janssen JW van den Hout M Mooij M Bronikowski MJ Willis PA Smalley RE Kouwenhoven LP Dekker C 《Nature》2001,412(6847):617-620
The drive towards the development of molecular electronics is placing increasing demands on the level of control that must be exerted on the electronic structure of materials. Proposed device architectures ultimately rely on tuning the interactions between individual electronic states, which amounts to controlling the detailed spatial structure of the electronic wavefunctions in the constituent molecules. Few experimental tools are available to probe this spatial structure directly, and the shapes of molecular wavefunctions are usually only known from theoretical investigations. Here we present scanning tunnelling spectroscopy measurements of the two-dimensional structure of individual wavefunctions in metallic single-walled carbon nanotubes; these measurements reveal spatial patterns that can be directly understood from the electronic structure of a single graphite sheet, and which represent an elegant illustration of Bloch's theorem at the level of individual wavefunctions. We also observe energy-dependent interference patterns in the wavefunctions and exploit these to directly measure the linear electronic dispersion relation of the metallic single-walled carbon nanotube. 相似文献
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Summary
Kluyvera, a proposed genus formerly known as Enteric group 8, was found to have similar enzyme profiles among the present 3 groups.Kluyvera species group 3 showed the most heterogeneous enzyme reactions.To whom reprint requests should be addressed. 相似文献
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