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21.
Benjamin Weiss 《Chemistry and physics of lipids》1977,19(4):347-355
Cerebroside analogues were synthesized from DL-threo-and DL-erythro-3-phenylserines by the following sequence of reactions: estirification, N-acylation, reduction with sodium bis (2-methoxyethoxy)-aluminum hydride (SMEAH), and condensation with acetobromoglucose followed by deacetylation. Mass spectrometry disclosed that the glycosidic bond was formed at the primary hydroxyl group. 相似文献
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Elliott C. Kulakowski Joseph Maturo Stephen W. Schaffer 《Archives of biochemistry and biophysics》1981,210(1):204-209
Cardiac sarcolemma preparations of both pig and rat ventricles were found to possess two sets of taurine-binding components. The two proteins from pig heart were solubilized with the detergent Ammonyx-Lo. Characterization of these solubilized proteins revealed that both components are glycoproteins and retain the binding properties observed for the membrane isolate. However, the characterization also revealed several differences between the proteins including their binding specificities, their affinities for taurine, their binding isotherms, and their molecular sizes. Possible functions of these two taurine-binding proteins are discussed. 相似文献
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Background
Many molecules are flexible and undergo significant shape deformation as part of their function, and yet most existing molecular shape comparison (MSC) methods treat them as rigid bodies, which may lead to incorrect shape recognition. 相似文献25.
D. C. Coleman R. V. Anderson C. V. Cole E. T. Elliott L. Woods M. K. Campion 《Microbial ecology》1977,4(4):373-380
Flows of biomass and respiratory carbon were studied in a series of propylene-oxide sterilized soil microcosms. One-half of the microcosms received three pulsed additions of 200 ppm glucose-carbon to mimic rhizosphere carbon inputs. Biotic variables were: bacteria (Pseudomonas) alone, or amoebae (Acanthamoeba) and nematodes (Mesodiplogaster) singly, or both combined in the presence of bacteria.Over the 24-day experiment, respiration was significantly higher in the microcosms containing the bacterial grazers. Biomass accumulation by amoebae was significantly higher than that by nematodes. The nematodes respired up to 30-fold more CO2 per unit biomass than did amoebae. Similar amounts of carbon flowed into both respiratory and biomass carbon in microcosms with fauna, compared with the bacteria-alone microcosms. However, partitioning of available carbon by the microfauna varied considerably, with little biomass production and relatively more CO2-C produced in the nematode-containing microcosms. The amoebae, in contrast, allocated more carbon to tissue production (about 40% assimilation efficiency) and correspondingly less to CO2. 相似文献
26.
Genes for serum amyloid A proteins map to Chromosome 7 in the mouse 总被引:10,自引:0,他引:10
Summary Several restriction fragment length variants have been detected among inbred strains using a mouse serum amyloid A cDNA clone. Five variants were shown to segregate as a single genetic unit and were mapped to Chromosome 7 between the glucose phosphate isomerase locus (Gpi-1) and the pink eye dilution locus (p) using recombinant inbred and congenic strains. The finding that no major MspI or BclI restriction fragments were shared between digests of DNAs from a Chromosome 7 congenic strain and its inbred partner, indicate that most, and probably all, sequences detected with the probe are clustered on Chromosome 7. Aneuploid mapping was used to show that the serum amyloid A gene complex (Saa) is proximal to the Chromosome 7 breakpoint in T(7;X)1Ct, a translocation in which the middle third of Chromosome 7 is inserted into the X-chromosome. A survey of inbred strains revealed a single common Saa haplotype and eight rare haplotypes. The complex distribution of 14 different variants suggests that recombination may have played a role in haplotype evolution.This work was supported by grants GM18684 and CA33093 from the National Institute of General Medical Sciences and the National Cancer Institute, respectively. 相似文献
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Observed intensification of precipitation extremes, responsible for extensive societal impacts, are widely attributed to anthropogenic sources, which may include indirect effects of agricultural irrigation. However quantifying the effects of irrigation on far-downstream climate remains a challenge. We use three paired Community Earth System Model simulations to assess mechanisms of irrigation-induced precipitation trends and extremes in the conterminous US and the effect on the terrestrial carbon sink. Results suggest precipitation enhancement in the central US reduced drought conditions and increased regional carbon uptake, while further downstream, the heaviest precipitation events were more frequent and intense. Specifically, moisture advection from irrigation in the western U.S. and recycling of enhanced local convective precipitation produced very-heavy storm events that were 11% more intense and occurred 23% more frequently in the densely populated greater New York City region. 相似文献
30.
Global species delimitation and phylogeography of the circumtropical ‘sexy shrimp’ Thor amboinensis reveals a cryptic species complex and secondary contact in the Indo‐West Pacific
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