A SIMPLE ULTRACENTRIFUGE WITH PLASTIC ROTOR     

Stern KG 《Science (New York, N.Y.)》1942,95(2474):561-562

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Book reviews     

K. C. Pillai  B. Z. Siegel  S. M. Siegel  A. S. Kallend  Elmer Robinson  Arthur C. Stern 《Water, air, and soil pollution》1987,32(3-4):461-461

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Rapid and specific detection of hydroxyl radical using an ultraweak chemiluminescence analyzer and a low-level chemiluminescence emitter: application to hydroxyl radical-scavenging ability of aqueous extracts of Food constituents     

Tsai CH  Stern A  Chiou JF  Chern CL  Liu TZ 《Journal of agricultural and food chemistry》2001,49(5):2137-2141

With the availability of an ultraweak chemiluminescence analyzer, it is possible to monitor the production of a specific oxygen-derived reactive species, such as hydroxyl radical ((*)OH), whenever a suitable chemiluminescent probe is obtainable. Reported herein is the development of a rapid and specific method for detecting (*)OH production using a specific probe, indoxyl-beta-glucuronide (IBG), a low-level chemiluminescence emitter. Using the Fenton reagent as a source of (*)OH, it was shown that IBG could elicit a very strong intensity of chemiluminescence (CL) (16200 +/- 200 photon counts/s). Conversely, IBG was shown to be insensitive to either superoxide radical or hydrogen peroxide with their CL intensities nearly close to the background values (25 +/- 5 and 180 +/- 20 photon counts/s, respectively). Furthermore, it was also shown that this IBG-based CL production could be effectively quenched by the addition of (*)OH scavengers such as sodium salicylate, dimethyl sulfoxide, and penicillamine to the assay system. Taken together, these data indicate that IBG is a specific CL probe suitable for monitoring the production of (*)OH. This system demonstrated inhibitory activities of various aqueous extracts of food constituents on the CL of hydroxyl radicals generated by Fenton's reagents with the order of scavenging efficiencies being Prunus mume > Cordyceps sinensin > Lilium lancifolium > Astragalus membranceus.  相似文献   

Book reviews     

K. C. Pillai  Arthur C. Stern  T. Viraraghavan  Michel Benarie  G. F. Humphrey  D. P. Ormrod  Jan S. M. Boleij  Michael Waldichuk  Jan Smeets 《Water, air, and soil pollution》1985,26(3):307-326

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Androgen accumulation andbinding to macromolecules in seminal vesicles: inhibition cyproterone   总被引：4，自引：0，他引：4  

J M Stern  A J Eisenfeld 《Science (New York, N.Y.)》1969,166(902):233-235

Cyproterone reduces the accumulation of testosterone and dihydrotestosterone in seminal vesicles 30 minutes after intravenous administration of tritiated testosterone to castrated rats. Testosterone, added in vitro, binds to macromolecules from the supernatant fraction of the seminal vesicle homogenates; this interaction is antagonized competitively by cyproterone. Cyproterone may diminish androgenic effects by competition for binding molecules.  相似文献   

Interleukin-2 induction of T-cell G1 progression and c-myb expression   总被引：36，自引：0，他引：36  

J B Stern  K A Smith 《Science (New York, N.Y.)》1986,233(4760):203-206

In studies to determine the biochemical mechanisms responsible for cell proliferation, synchronized T cells were used as a model for cellular growth control. By metabolic and morphologic criteria, it was found that activation of the T-cell antigen receptor rendered the cells responsive to interleukin-2 (IL-2), but did not move them through the cell cycle. Instead, IL-2 stimulated G1 progression to S phase, or lymphocyte "blastic transformation." During IL-2-promoted G1 progression, expression of the cellular proto-oncogene c-myb was induced transiently at six to seven times basal levels, maximal levels occurring at the midpoint of G1.  相似文献   

New horizons mapping of Europa and Ganymede     

Grundy WM  Buratti BJ  Cheng AF  Emery JP  Lunsford A  McKinnon WB  Moore JM  Newman SF  Olkin CB  Reuter DC  Schenk PM  Spencer JR  Stern SA  Throop HB  Weaver HA;New Horizons Team 《Science (New York, N.Y.)》2007,318(5848):234-237

The New Horizons spacecraft observed Jupiter's icy satellites Europa and Ganymede during its flyby in February and March 2007 at visible and infrared wavelengths. Infrared spectral images map H2O ice absorption and hydrated contaminants, bolstering the case for an exogenous source of Europa's "non-ice" surface material and filling large gaps in compositional maps of Ganymede's Jupiter-facing hemisphere. Visual wavelength images of Europa extend knowledge of its global pattern of arcuate troughs and show that its surface scatters light more isotropically than other icy satellites.  相似文献   

THE RHESUS GENE AND THE EFFECT OF CONSANGUINITY     

Stern C  Charles DR 《Science (New York, N.Y.)》1945,101(2621):305-307

It is pointed out that consanguinity among the parents of children affected by erythroblastosis foetalis should be less than in the general population, unless other loci than the R locus are involved in the disease.  相似文献   

Contraceptives and dysplasia: higher rate for pill choosers     

E Stern  V A Clark  C F Coffelt 《Science (New York, N.Y.)》1970,169(944):497-498

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Mantle phase changes and deep-earthquake faulting in subducting lithosphere   总被引：2，自引：0，他引：2  

Kirby SH  Durham WB  Stern LA 《Science (New York, N.Y.)》1991,252(5003):216-225

Inclined zones of earthquakes are the primary expression of lithosphere subduction. A distinct deep population of subduction-zone earthquakes occurs at depths of 350 to 690 kilometers. At those depths ordinary brittle fracture and frictional sliding, the faulting processes of shallow earthquakes, are not expected. A fresh understanding of these deep earthquakes comes from developments in several areas of experimental and theoretical geophysics, including the discovery and characterization of transformational faulting, a shear instability connected with localized phase transformations under nonhydrostatic stress. These developments support the hypothesis that deep earthquakes represent transformational faulting in a wedge of olivine-rich peridotite that is likely to persist metastably in coldest plate interiors to depths as great as 690 km. Predictions based on this deep structure of mantle phase changes are consistent with the global depth distribution of deep earthquakes, the maximum depths of earthquakes in individual subductions zones, and key source characteristics of deep events.  相似文献