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11.
Granulocytes from diabetic subjects have impaired ability to engulf bacteria; the data obtained suggest that the alterations are correlated with an increase in surface hydrophobicity, as measured by contact angle. 相似文献
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Disney MJ Romano JD Garcia-Appadoo DA West AA Dalcanton JJ Cortese L 《Nature》2008,455(7216):1082-1084
Galaxies are complex systems the evolution of which apparently results from the interplay of dynamics, star formation, chemical enrichment and feedback from supernova explosions and supermassive black holes. The hierarchical theory of galaxy formation holds that galaxies are assembled from smaller pieces, through numerous mergers of cold dark matter. The properties of an individual galaxy should be controlled by six independent parameters including mass, angular momentum, baryon fraction, age and size, as well as by the accidents of its recent haphazard merger history. Here we report that a sample of galaxies that were first detected through their neutral hydrogen radio-frequency emission, and are thus free from optical selection effects, shows five independent correlations among six independent observables, despite having a wide range of properties. This implies that the structure of these galaxies must be controlled by a single parameter, although we cannot identify this parameter from our data set. Such a degree of organization appears to be at odds with hierarchical galaxy formation, a central tenet of the cold dark matter model in cosmology. 相似文献
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G. Frenguelli B. Romano F. Ferranti E. Ciriciofolo 《Cellular and molecular life sciences : CMLS》1984,40(3):256-257
Summary A study was made of the variation in the fatty acid composition of the oil in the developing seed of the Rafal cultivar of theBrassica napus L. cultivated in central Italy. The oil content reaches its maximum level 60 days after the petals fall. The increase in the percentage of oleic acid is negatively correlated with the palmitic, stearic and linoleic acid content. 相似文献
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A recurrent 15q13.3 microdeletion syndrome associated with mental retardation and seizures 总被引:1,自引:0,他引:1
Sharp AJ Mefford HC Li K Baker C Skinner C Stevenson RE Schroer RJ Novara F De Gregori M Ciccone R Broomer A Casuga I Wang Y Xiao C Barbacioru C Gimelli G Bernardina BD Torniero C Giorda R Regan R Murday V Mansour S Fichera M Castiglia L Failla P Ventura M Jiang Z Cooper GM Knight SJ Romano C Zuffardi O Chen C Schwartz CE Eichler EE 《Nature genetics》2008,40(3):322-328
We report a recurrent microdeletion syndrome causing mental retardation, epilepsy and variable facial and digital dysmorphisms. We describe nine affected individuals, including six probands: two with de novo deletions, two who inherited the deletion from an affected parent and two with unknown inheritance. The proximal breakpoint of the largest deletion is contiguous with breakpoint 3 (BP3) of the Prader-Willi and Angelman syndrome region, extending 3.95 Mb distally to BP5. A smaller 1.5-Mb deletion has a proximal breakpoint within the larger deletion (BP4) and shares the same distal BP5. This recurrent 1.5-Mb deletion contains six genes, including a candidate gene for epilepsy (CHRNA7) that is probably responsible for the observed seizure phenotype. The BP4-BP5 region undergoes frequent inversion, suggesting a possible link between this inversion polymorphism and recurrent deletion. The frequency of these microdeletions in mental retardation cases is approximately 0.3% (6/2,082 tested), a prevalence comparable to that of Williams, Angelman and Prader-Willi syndromes. 相似文献
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Tagliaferri G Goad M Chincarini G Moretti A Campana S Burrows DN Perri M Barthelmy SD Gehrels N Krimm H Sakamoto T Kumar P Mészáros PI Kobayashi S Zhang B Angelini L Banat P Beardmore AP Capalbi M Covino S Cusumano G Giommi P Godet O Hill JE Kennea JA Mangano V Morris DC Nousek JA O'Brien PT Osborne JP Pagani C Page KL Romano P Stella L Wells A 《Nature》2005,436(7053):985-988
'Long' gamma-ray bursts (GRBs) are commonly accepted to originate in the explosion of particularly massive stars, which give rise to highly relativistic jets. Inhomogeneities in the expanding flow result in internal shock waves that are believed to produce the gamma-rays we see. As the jet travels further outward into the surrounding circumstellar medium, 'external' shocks create the afterglow emission seen in the X-ray, optical and radio bands. Here we report observations of the early phases of the X-ray emission of five GRBs. Their X-ray light curves are characterised by a surprisingly rapid fall-off for the first few hundred seconds, followed by a less rapid decline lasting several hours. This steep decline, together with detailed spectral properties of two particular bursts, shows that violent shock interactions take place in the early jet outflows. 相似文献
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Barthelmy SD Chincarini G Burrows DN Gehrels N Covino S Moretti A Romano P O'Brien PT Sarazin CL Kouveliotou C Goad M Vaughan S Tagliaferri G Zhang B Antonelli LA Campana S Cummings JR D'Avanzo P Davies MB Giommi P Grupe D Kaneko Y Kennea JA King A Kobayashi S Melandri A Meszaros P Nousek JA Patel S Sakamoto T Wijers RA 《Nature》2005,438(7070):994-996
Two short (< 2 s) gamma-ray bursts (GRBs) have recently been localized and fading afterglow counterparts detected. The combination of these two results left unclear the nature of the host galaxies of the bursts, because one was a star-forming dwarf, while the other was probably an elliptical galaxy. Here we report the X-ray localization of a short burst (GRB 050724) with unusual gamma-ray and X-ray properties. The X-ray afterglow lies off the centre of an elliptical galaxy at a redshift of z = 0.258 (ref. 5), coincident with the position determined by ground-based optical and radio observations. The low level of star formation typical for elliptical galaxies makes it unlikely that the burst originated in a supernova explosion. A supernova origin was also ruled out for GRB 050709 (refs 3, 31), even though that burst took place in a galaxy with current star formation. The isotropic energy for the short bursts is 2-3 orders of magnitude lower than that for the long bursts. Our results therefore suggest that an alternative source of bursts--the coalescence of binary systems of neutron stars or a neutron star-black hole pair--are the progenitors of short bursts. 相似文献
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Koolen DA Vissers LE Pfundt R de Leeuw N Knight SJ Regan R Kooy RF Reyniers E Romano C Fichera M Schinzel A Baumer A Anderlid BM Schoumans J Knoers NV van Kessel AG Sistermans EA Veltman JA Brunner HG de Vries BB 《Nature genetics》2006,38(9):999-1001
Submicroscopic genomic copy number changes have been identified only recently as an important cause of mental retardation. We describe the detection of three interstitial, overlapping 17q21.31 microdeletions in a cohort of 1,200 mentally retarded individuals associated with a clearly recognizable clinical phenotype of mental retardation, hypotonia and a characteristic face. The deletions encompass the MAPT and CRHR1 genes and are associated with a common inversion polymorphism. 相似文献
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Riassunto Topi immunizzati con membrane isolate daSalmonella typhimurium presentano una resistenza alla infezione sperimentale uguale a quella dimostrata da topi immunizzati conSalmonelle viventi. 相似文献