Heparin affinity: purification of a tumor-derived capillary endothelial cell growth factor   总被引：73，自引：0，他引：73  

Y Shing  J Folkman  R Sullivan  C Butterfield  J Murray  M Klagsbrun 《Science (New York, N.Y.)》1984,223(4642):1296-1299

A tumor-derived growth factor that stimulates the proliferation of capillary endothelial cells has a very strong affinity for heparin. This heparin affinity makes it possible to purify the growth factor to a single-band preparation in a rapid two-step procedure. The purified growth factor is a cationic polypeptide, has a molecular weight of about 18,000, and stimulates capillary endothelial cell proliferation at a concentration of about 1 nanogram per milliliter.  相似文献   

The end of the beginning     

Murray B 《Science (New York, N.Y.)》1982,215(4532):459

  相似文献   

The Halogen-Metal Interconversion Reaction and Its Application to the Synthesis of Nicotinic Acid Labeled With Isotopic Carbon     

Murray A  Foreman WW  Langham W 《Science (New York, N.Y.)》1947,106(2751):277

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Evidence that the reactivity of the martian soil is due to superoxide ions     

Yen AS  Kim SS  Hecht MH  Frant MS  Murray B 《Science (New York, N.Y.)》2000,289(5486):1909-1912

The Viking Landers were unable to detect evidence of life on Mars but, instead, found a chemically reactive soil capable of decomposing organic molecules. This reactivity was attributed to the presence of one or more as-yet-unidentified inorganic superoxides or peroxides in the martian soil. Using electron paramagnetic resonance spectroscopy, we show that superoxide radical ions (O2-) form directly on Mars-analog mineral surfaces exposed to ultraviolet radiation under a simulated martian atmosphere. These oxygen radicals can explain the reactive nature of the soil and the apparent absence of organic material at the martian surface.  相似文献   

Dominoes and clocks: the union of two views of the cell cycle   总被引：96，自引：0，他引：96  

A W Murray  M W Kirschner 《Science (New York, N.Y.)》1989,246(4930):614-621

We review the recent advances in understanding transitions within the cell cycle. These have come from both genetic and biochemical approaches. We discuss the phylogenetic conservation of the mechanisms that induce mitosis and their implications for other transitions in the cell cycle.  相似文献   

A corticosteroid receptor in neuronal membranes   总被引：22，自引：0，他引：22  

M Orchinik  T F Murray  F L Moore 《Science (New York, N.Y.)》1991,252(5014):1848-1851

Steroids may rapidly alter neuronal function and behavior through poorly characterized, direct actions on neuronal membranes. The membrane-bound receptors mediating these behavioral responses have not been identified. [3H]Corticosterone labels a population of specific, high-affinity recognition sites (dissociation constant = 0.51 nanomolar) in synaptic membranes from an amphibian brain. These binding sites were localized by receptor autoradiography in the neuropil, outside the regions of perikarya. The affinities of corticoids for this [3H]corticosterone binding site were linearly related to their potencies in rapidly suppressing male reproductive behavior. Thus, it appears that brain membranes contain a corticosteroid receptor that could participate in the regulation of behavior.  相似文献   

Intracellular absorption difference spectrum of Limulus extra-ocular photolabile pigment   总被引：7，自引：0，他引：7  

G C Murray 《Science (New York, N.Y.)》1966,154(753):1182-1183

Microspectrophotometric measurements on single cell bodies located on the surface of the"lateral olfactory nerve" of Limulus polyphemus show they contain a photolabile pigment with a absorption-difference spectrum similar in shape to that of most other visual pigments and with a maximum absorption at 529 +/- 5 nanometers.  相似文献   

Ultrafast bond softening in bismuth: mapping a solid's interatomic potential with X-rays     

Fritz DM  Reis DA  Adams B  Akre RA  Arthur J  Blome C  Bucksbaum PH  Cavalieri AL  Engemann S  Fahy S  Falcone RW  Fuoss PH  Gaffney KJ  George MJ  Hajdu J  Hertlein MP  Hillyard PB  Horn-von Hoegen M  Kammler M  Kaspar J  Kienberger R  Krejcik P  Lee SH  Lindenberg AM  McFarland B  Meyer D  Montagne T  Murray ED  Nelson AJ  Nicoul M  Pahl R  Rudati J  Schlarb H  Siddons DP  Sokolowski-Tinten K  Tschentscher T  von der Linde D  Hastings JB 《Science (New York, N.Y.)》2007,315(5812):633-636

Intense femtosecond laser excitation can produce transient states of matter that would otherwise be inaccessible to laboratory investigation. At high excitation densities, the interatomic forces that bind solids and determine many of their properties can be substantially altered. Here, we present the detailed mapping of the carrier density-dependent interatomic potential of bismuth approaching a solid-solid phase transition. Our experiments combine stroboscopic techniques that use a high-brightness linear electron accelerator-based x-ray source with pulse-by-pulse timing reconstruction for femtosecond resolution, allowing quantitative characterization of the interatomic potential energy surface of the highly excited solid.  相似文献   

Extraterrestrial intelligence: an observational approach     

Murray B  Gulkis S  Edelson RE 《Science (New York, N.Y.)》1978,199(4328):485-492

The microwave region of the electromagnetic spectrum, a plausible regime for signals from extraterrestrial intelligences, is largely unexplored. With new technology, particularly in data processing and low-noise reception, surveys can be conducted over broad regions of frequency and space with existing antennas at flux densities plausible for interstellar signals. An all-sky, broad-band survey lasting perhaps 5 years can be structured so that even negative results would establish significant boundaries on the regime in which such signals may be found. The technology and techniques developed and much of the data acquired would be applicable to radio astronomy and deep-space communications.  相似文献   

Computational improvements reveal great bacterial diversity and high metal toxicity in soil   总被引：4，自引：0，他引：4  

Gans J  Wolinsky M  Dunbar J 《Science (New York, N.Y.)》2005,309(5739):1387-1390

The complexity of soil bacterial communities has thus far confounded effective measurement. However, with improved analytical methods, we show that the abundance distribution and total diversity can be deciphered. Reanalysis of reassociation kinetics for bacterial community DNA from pristine and metal-polluted soils showed that a power law best described the abundance distributions. More than one million distinct genomes occurred in the pristine soil, exceeding previous estimates by two orders of magnitude. Metal pollution reduced diversity more than 99.9%, revealing the highly toxic effect of metal contamination, especially for rare taxa.  相似文献