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931.
Recent advances in identifying the functions of gangliosides 总被引:6,自引:0,他引:6
P H Fishman 《Chemistry and physics of lipids》1986,42(1-3):137-151
The recent development of several new approaches has proven extremely useful in identifying functions for gangliosides, the sialic-acid containing glycosphingolipids. The first is the incorporation of exogenous gangliosides into the plasma membrane of ganglioside-deficient cells. Using this approach, specific gangliosides have been identified as the receptors for certain bacterial toxins and viruses and as important factors in the organization of fibronectin into an extracellular matrix. The second approach has been a ligand blotting technique which allows detection of ganglioside-binding proteins such as toxins and antibodies. Gangliosides are separated by thin-layer chromatography and overlain with the protein of interest. Specific binding of the ligand to gangliosides can then be detected by either direct or indirect methods. The third approach is the use of the B or binding subunit of cholera toxin as a specific probe for endogenous plasma membrane ganglioside function. The ability of the B subunit to alter the growth of cells directly demonstrates a role for gangliosides as biotransducers of signals for the regulation of cell growth. 相似文献
932.
A new staining method is described using naphthalene black 12B and Gurr's improved R66 Giemsa for staining all known crystal types produced by Bacillus thuringiensis. 相似文献
933.
P P Mortimer 《BMJ (Clinical research ed.)》1987,294(6587):1602-1605
934.
Biological destruction of coral reefs 总被引:10,自引:3,他引:7
P. A. Hutchings 《Coral reefs (Online)》1986,4(4):239-252
The major agents of biological destruction of coral reefs can be divided into grazers, etchers and borers. Each of these groups is reviewed on a world wide basis, together with the mechanisms by which they destroy the coral substrate. Rates of bioerosion attributed to major agents of grazers, etchers and borers are given, together with limitations of some of the measurements. Recent work is highlighting the variability in rates of bioerosion both over time and space. Factors which may be responsible for this variability are discussed. Bioerosion is a major factor influencing reef morphology and the ways in which this is achieved is discussed in some detail. Although the review concentrates mainly on present day reefs, some attempt is made to consider the impact of bioerosion on older reefs. 相似文献
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P Gold 《BioTechniques》1992,13(1):132-134
The use of a novel gel-digesting enzyme preparation provides an easy, rapid and convenient method to quantitatively recover PCR-amplified DNA from low melting point agarose gels. The PCR products purified using this method were readily sequenced and yielded good and unambiguous sequence data. 相似文献
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Isolation of Temperature-Sensitive Membrane Mutants of Escherichia coli K-12 总被引:1,自引:1,他引:0 下载免费PDF全文
Johan F. Steenbakkers J. H. F. F. Broekman A. Kerkenaar P. G. De Haan 《Journal of bacteriology》1973,116(2):535-540
Mutants with impaired biosynthesis of unsaturated fatty acids or altered metabolism of the phospholipids were isolated at a rather high frequency from a set of temperature-sensitive lysis mutants. It is suggested that preselection for the lysis phenotype makes it possible to isolate several kinds of mutants affected in the integrity of the cytoplasmic membrane. 相似文献