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排序方式: 共有80条查询结果,搜索用时 15 毫秒
41.
42.
Impaired response to interferon-alpha/beta and lethal viral disease in human STAT1 deficiency 总被引:22,自引:0,他引:22
43.
Gene expression profiling predicts clinical outcome of breast cancer 总被引:243,自引:0,他引:243
van 't Veer LJ Dai H van de Vijver MJ He YD Hart AA Mao M Peterse HL van der Kooy K Marton MJ Witteveen AT Schreiber GJ Kerkhoven RM Roberts C Linsley PS Bernards R Friend SH 《Nature》2002,415(6871):530-536
Breast cancer patients with the same stage of disease can have markedly different treatment responses and overall outcome. The strongest predictors for metastases (for example, lymph node status and histological grade) fail to classify accurately breast tumours according to their clinical behaviour. Chemotherapy or hormonal therapy reduces the risk of distant metastases by approximately one-third; however, 70-80% of patients receiving this treatment would have survived without it. None of the signatures of breast cancer gene expression reported to date allow for patient-tailored therapy strategies. Here we used DNA microarray analysis on primary breast tumours of 117 young patients, and applied supervised classification to identify a gene expression signature strongly predictive of a short interval to distant metastases ('poor prognosis' signature) in patients without tumour cells in local lymph nodes at diagnosis (lymph node negative). In addition, we established a signature that identifies tumours of BRCA1 carriers. The poor prognosis signature consists of genes regulating cell cycle, invasion, metastasis and angiogenesis. This gene expression profile will outperform all currently used clinical parameters in predicting disease outcome. Our findings provide a strategy to select patients who would benefit from adjuvant therapy. 相似文献
44.
The motor side of depth vision 总被引:7,自引:0,他引:7
To achieve stereoscopic vision, the brain must search for corresponding image features on the two retinas. As long as the eyes stay still, corresponding features are confined to narrow bands called epipolar lines. But when the eyes change position, the epipolar lines migrate on the retinas. To find the matching features, the brain must either search different retinal bands depending on current eye position, or search retina-fixed zones that are large enough to cover all usual locations of the epipolar lines. Here we show, using a new type of stereogram in which the depth image vanishes at certain gaze elevations, that the search zones are retina-fixed. This being the case, motor control acquires a crucial function in depth vision: we show that the eyes twist about their lines of sight in a way that reduces the motion of the epipolar lines, allowing stereopsis to get by with smaller search zones and thereby lightening its computational load. 相似文献
45.
Summary Solanocapsine has for the first time been degraded to a known steroid, 3-acetoxy-16-hydroxy-5-bis-22, 23-nor-cholanic lactone. According to this and further experimental evidence, solanocapsine is 3-amino-22, 26-imino-16, 23-epoxy-5, 22, 23, 25 -cholestan-23-ol.
Solanum-Alkaloide. XII. Mitteilung. — XI. Mitteilung:K. Schreiber undH. Rönsch, Abh. dtsch. Akad. Wiss., Berlin, Kl. Chem., Geol., Biol. (im Druck). 相似文献
Solanum-Alkaloide. XII. Mitteilung. — XI. Mitteilung:K. Schreiber undH. Rönsch, Abh. dtsch. Akad. Wiss., Berlin, Kl. Chem., Geol., Biol. (im Druck). 相似文献
46.
V. Schreiber A. Eckertová Z. Franc J. Kočí M. Rybák V. Kmentová 《Cellular and molecular life sciences : CMLS》1961,17(6):264-265
Zusammenfassung Die elektrophoretisch isolierte Franktion des hypothalamischen Extraktes erhöhtin vitro die Sekretion des thyreotropen Hormons aus der Adenohypophyse der Ratte in der Krebs-Phosphat-Ringerlösung mit 300 mg% Glukose. Die Fraktion selbst besitzt keine TSH-Wirkung. 相似文献
47.
48.
Schreiber A Stengel F Zhang Z Enchev RI Kong EH Morris EP Robinson CV da Fonseca PC Barford D 《Nature》2011,470(7333):227-232
The anaphase-promoting complex or cyclosome (APC/C) is an unusually large E3 ubiquitin ligase responsible for regulating defined cell cycle transitions. Information on how its 13 constituent proteins are assembled, and how they interact with co-activators, substrates and regulatory proteins is limited. Here, we describe a recombinant expression system that allows the reconstitution of holo APC/C and its sub-complexes that, when combined with electron microscopy, mass spectrometry and docking of crystallographic and homology-derived coordinates, provides a precise definition of the organization and structure of all essential APC/C subunits, resulting in a pseudo-atomic model for 70% of the APC/C. A lattice-like appearance of the APC/C is generated by multiple repeat motifs of most APC/C subunits. Three conserved tetratricopeptide repeat (TPR) subunits (Cdc16, Cdc23 and Cdc27) share related superhelical homo-dimeric architectures that assemble to generate a quasi-symmetrical structure. Our structure explains how this TPR sub-complex, together with additional scaffolding subunits (Apc1, Apc4 and Apc5), coordinate the juxtaposition of the catalytic and substrate recognition module (Apc2, Apc11 and Apc10 (also known as Doc1)), and TPR-phosphorylation sites, relative to co-activator, regulatory proteins and substrates. 相似文献
49.
Rosy El Ramy Najat Magroun Nadia Messadecq Laurent R. Gauthier François D. Boussin Ullas Kolthur-Seetharam Valérie Schreiber Michael W. McBurney Paolo Sassone-Corsi Françoise Dantzer 《Cellular and molecular life sciences : CMLS》2009,66(19):3219-3234
Poly(ADP-ribose) polymerase-1 (Parp-1) and the protein deacetylase SirT1 are two of the most effective NAD+-consuming enzymes in the cell with key functions in genome integrity and chromatin-based pathways. Here, we examined the
in vivo crosstalk between both proteins. We observed that the double disruption of both genes in mice tends to increase late
post-natal lethality before weaning consistent with important roles of both proteins in genome integrity during mouse development.
We identified increased spontaneous telomeric abnormalities associated with decreased cell growth in the absence of either
SirT1 or SirT1 and Parp-1 in mouse cells. In contrast, the additional disruption of Parp-1 rescued the abnormal pericentric
heterochromatin, the nucleolar disorganization and the mitotic defects observed in SirT1-deficient cells. Together, these
findings are in favor of key functions of both proteins in cellular response to DNA damage and in the modulation of histone
modifications associated with constitutive heterochromatin integrity. 相似文献
50.
Kuzyk A Schreiber R Fan Z Pardatscher G Roller EM Högele A Simmel FC Govorov AO Liedl T 《Nature》2012,483(7389):311-314
Matter structured on a length scale comparable to or smaller than the wavelength of light can exhibit unusual optical properties. Particularly promising components for such materials are metal nanostructures, where structural alterations provide a straightforward means of tailoring their surface plasmon resonances and hence their interaction with light. But the top-down fabrication of plasmonic materials with controlled optical responses in the visible spectral range remains challenging, because lithographic methods are limited in resolution and in their ability to generate genuinely three-dimensional architectures. Molecular self-assembly provides an alternative bottom-up fabrication route not restricted by these limitations, and DNA- and peptide-directed assembly have proved to be viable methods for the controlled arrangement of metal nanoparticles in complex and also chiral geometries. Here we show that DNA origami enables the high-yield production of plasmonic structures that contain nanoparticles arranged in nanometre-scale helices. We find, in agreement with theoretical predictions, that the structures in solution exhibit defined circular dichroism and optical rotatory dispersion effects at visible wavelengths that originate from the collective plasmon-plasmon interactions of the nanoparticles positioned with an accuracy better than two nanometres. Circular dichroism effects in the visible part of the spectrum have been achieved by exploiting the chiral morphology of organic molecules and the plasmonic properties of nanoparticles, or even without precise control over the spatial configuration of the nanoparticles. In contrast, the optical response of our nanoparticle assemblies is rationally designed and tunable in handedness, colour and intensity-in accordance with our theoretical model. 相似文献