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101.
Campbell DB Jurgens RF Dyce RB Harris FS Pettengill GH 《Science (New York, N.Y.)》1970,170(3962):1090-1092
A radar interferometer was used to map unambiguously the surface reflectivity of Venus in the polarized mode at a wavelength of 70 centimeters. The observed region extended from 260 degrees to 30 degrees in longitude and from -60 degrees to 50 degrees in latitude with a surface resolution of approximately 3 degrees by 3 degrees . The result agrees well in most respects with earlier maps made elsewhere at shorter wavelengths and, in addition, discloses a number of new "features." 相似文献
102.
Harris JE 《Science (New York, N.Y.)》1914,40(1031):491-493
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Simmen MW Leitgeb S Charlton J Jones SJ Harris BR Clark VH Bird A 《Science (New York, N.Y.)》1999,283(5405):1164-1167
The genome of the invertebrate chordate Ciona intestinalis was found to be a stable mosaic of methylated and nonmethylated domains. Multiple copies of an apparently active long terminal repeat retrotransposon and a long interspersed element are nonmethylated and a large fraction of abundant short interspersed elements are also methylation free. Genes, by contrast, are predominantly methylated. These data are incompatible with the genome defense model, which proposes that DNA methylation in animals is primarily targeted to endogenous transposable elements. Cytosine methylation in this urochordate may be preferentially directed to genes. 相似文献
106.
Harris WA 《Science (New York, N.Y.)》1988,240(4849):229
107.
Solomon DA Kim T Diaz-Martinez LA Fair J Elkahloun AG Harris BT Toretsky JA Rosenberg SA Shukla N Ladanyi M Samuels Y James CD Yu H Kim JS Waldman T 《Science (New York, N.Y.)》2011,333(6045):1039-1043
Most cancer cells are characterized by aneuploidy, an abnormal number of chromosomes. We have identified a clue to the mechanistic origins of aneuploidy through integrative genomic analyses of human tumors. A diverse range of tumor types were found to harbor deletions or inactivating mutations of STAG2, a gene encoding a subunit of the cohesin complex, which regulates the separation of sister chromatids during cell division. Because STAG2 is on the X chromosome, its inactivation requires only a single mutational event. Studying a near-diploid human cell line with a stable karyotype, we found that targeted inactivation of STAG2 led to chromatid cohesion defects and aneuploidy, whereas in two aneuploid human glioblastoma cell lines, targeted correction of the endogenous mutant alleles of STAG2 led to enhanced chromosomal stability. Thus, genetic disruption of cohesin is a cause of aneuploidy in human cancer. 相似文献
108.
Miller AD Bezel I Gaffney KJ Garrett-Roe S Liu SH Szymanski P Harris CB 《Science (New York, N.Y.)》2002,297(5584):1163-1166
Ultrafast two-photon photoemission has been used to study electron solvation at two-dimensional metal/polar-adsorbate interfaces. The molecular motion that causes the excess electron solvation is manifested as a dynamic shift in the electronic energy. Although the initially excited electron is delocalized in the plane of the interface, interactions with the adsorbate can lead to its localization. A method for determining the spatial extent of the localized electron in the plane of the interface has been developed. This spatial extent was measured to be on the order of a single adsorbate molecule. 相似文献
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Harris FS 《Science (New York, N.Y.)》1914,40(1023):215-216