BLANCAN AS A TIME TERM IN THE CENTRAL GREAT PLAINS     

Elias MK  Frye JC  Hibbard CW  Reed EC  Schultz CB 《Science (New York, N.Y.)》1945,101(2620):270-271

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A late-transition metal oxo complex: K7Na9[O=PtIV(H2O)L2], L = [PW9O34]9-     

Anderson TM  Neiwert WA  Kirk ML  Piccoli PM  Schultz AJ  Koetzle TF  Musaev DG  Morokuma K  Cao R  Hill CL 《Science (New York, N.Y.)》2004,306(5704):2074-2077

Terminal mono-oxo complexes of the late transition metal elements have long been considered too unstable to synthesize because of repulsion between the oxygen electrons and the mostly filled metal d orbitals. A platinum(IV)-oxo compound flanked by two polytungstate ligands, K7Na9[O=Pt(H2O)L2], L = [PW9O34(9-)], has now been prepared and isolated at room temperature as air-stable brown crystals. X-ray and neutron diffraction at 30 kelvin revealed a very short [1.720(18) angstrom] Pt-O bond and no evidence of a hydrogen atom at the terminal oxygen, ruling out a better precedented Pt-OH complex. Density functional theory and spectroscopic data account for the stability of the Pt(IV)-oxo unit by electron withdrawal into delocalized orbitals of the polytungstates.  相似文献   

Developmental expression of PDGF, TGF-alpha, and TGF-beta genes in preimplantation mouse embryos   总被引：49，自引：0，他引：49  

D A Rappolee  C A Brenner  R Schultz  D Mark  Z Werb 《Science (New York, N.Y.)》1988,241(4874):1823-1825

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Introduction of nucleophiles and spectroscopic probes into antibody combining sites   总被引：4，自引：0，他引：4  

S J Pollack  G R Nakayama  P G Schultz 《Science (New York, N.Y.)》1988,242(4881):1038-1040

A general chemical strategy has been developed whereby antibody combining sites can be selectively derivatized with natural or synthetic molecules, such as catalytic groups, drugs, metals, or reporter molecules. Cleavable affinity labels were used to selectively introduce a thiol into the combining site of the immunoglobulin A MOPC 315. This thiol acted both as a nucleophile to accelerate ester thiolysis 60,000-fold and as a handle for selectively derivatizing the antibody with additional functional groups. For example, derivatization of the antibody with a fluorophore made possible a direct spectroscopic assay of antibody-ligand complexation. This chemistry should not only extend our ability to exploit antibody specificity in chemical catalysis, diagnostics, and therapeutics, but may also prove generally applicable to the functional modification of other proteins for which detailed structural information is unavailable.  相似文献   

Effect of sugars on transport of alanine in intestine     

R A Chez  S G Schultz  P F Curran 《Science (New York, N.Y.)》1966,153(739):1012-1013

The eflect of glucose and galactose on transport of alanine by rabbit ileum has been investigated. Transmural transport and cellular ac cumulation of the amino acid were in hibited by the sugars, but alanine in flux across the mucosal border of the cells was unaltered.  相似文献