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Shula G. Blumenthal B. H. Ruebner R. M. Ikeda F. W. Hanson D. E. Bergstrom 《Cellular and molecular life sciences : CMLS》1977,33(5):592-593
Summary Protohemin is excreted in biles of primate fetuses and premature newborns. It also was found in relatively large quantities in the lower ileum and mesenteric lymph-nodes of newborn primates.This work was supported by National Institute of Child Health and Human Development, grants 1RO1 HD 07331-02 and 1F22 HD 00191-01. 相似文献
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YAN Quanren A. D. Hanson WANG Zongqi P. A. Druschke YAN Zhen WANG Tao & LU Haifeng . Institute of Geology Chinese Academy of Geological Sciences Bei-jing China . Department of Geosciences University of Nevada Las Vegas Las Vegas NV USA . Institute of Geology Geophysics Chinese Academy of Sciences Beijing China 《科学通报(英文版)》2004,49(16):1722-1729
TheGuanjiagouFormationisafault-boundterranelocatedintheSouthQinlingMountains,centralChina.Theageandtectonicsettingoftheconglomerateinthisformation(Guanjiagouconglomerate,GC)havebeencontroversialsincethe1940s,withnumerousconflictinginterpretationsandcorrelationsproposedbydifferentworkers.Forexample,itwasinitiallydescribedbyYeetal.(1944)[1],whointerpretedtheGCasSinian(LatestNeo-proterozoic)tillites.However,Huang[2]regardedtheGC,plustheBikouSystem(composedoftheBikouvolcanicandtheHengdant… 相似文献
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Résumé On expose une méthode simple par laquelle il a été possible de localiser exactement l'activité des anticorps ou des antigènes après électrophorèse. Cette méthode a été appliquée aux hémagglutinines du sérum et du lait, aux antitoxines et hémolysines. 相似文献
45.
Johnson AC Petta JR Taylor JM Yacoby A Lukin MD Marcus CM Hanson MP Gossard AC 《Nature》2005,435(7044):925-928
The spin of a confined electron, when oriented originally in some direction, will lose memory of that orientation after some time. Physical mechanisms leading to this relaxation of spin memory typically involve either coupling of the electron spin to its orbital motion or to nuclear spins. Relaxation of confined electron spin has been previously measured only for Zeeman or exchange split spin states, where spin-orbit effects dominate relaxation; spin flips due to nuclei have been observed in optical spectroscopy studies. Using an isolated GaAs double quantum dot defined by electrostatic gates and direct time domain measurements, we investigate in detail spin relaxation for arbitrary splitting of spin states. Here we show that electron spin flips are dominated by nuclear interactions and are slowed by several orders of magnitude when a magnetic field of a few millitesla is applied. These results have significant implications for spin-based information processing. 相似文献
46.
The type-1 pilus of Escherichia coli is the prototype of this class of hair-like, multimeric adhesive organelles. This pilus mediates adherence to mannose-containing receptors on mucosal epithelia and other cells. The type-1 pilus, in one of several serological variants, is expressed by nearly all E. coli strains, and its promotion of colonization by pathogenic bacteria and the protective effects of purified pilus vaccines suggest that it is important as a bacterial virulence factor. Both the adhesive function and the serological variation of the type-1 pilus have been attributed to the thousand or so pilin protein monomers making up the pilus rods. This idea has been contradicted by our earlier observations on an E. coli strain expressing adhesion-defective pili. More recent genetic evidence also indicates that auxiliary pilus proteins are required for adhesive function. We report here the identification of three previously undetected integral minor proteins on the type-1 pilus, and show that one of them is the receptor-binding adhesin. This protein is antigenically conserved among strains with different pilin serotypes and is located at the pilus tip. 相似文献
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C A Vernon J Gauldie J M Hanson J M Humphreys P E Smith A J Lawrence B E Banks 《Nature》1965,208(5008):382-383
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During the past few years, researchers have gained unprecedented control over spins in the solid state. What was considered almost impossible a decade ago, in both conceptual and practical terms, is now a reality: single spins can be isolated, initialized, coherently manipulated and read out using both electrical and optical techniques. Progress has been made towards full control of the quantum states of single and coupled spins in a variety of semiconductors and nanostructures, and towards understanding the mechanisms through which spins lose coherence in these systems. These abilities will allow pioneering investigations of fundamental quantum-mechanical processes and provide pathways towards applications in quantum information processing. 相似文献
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