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排序方式: 共有3474条查询结果,搜索用时 585 毫秒
951.
Identification of a universal Group B streptococcus vaccine by multiple genome screen 总被引:2,自引:0,他引:2
Maione D Margarit I Rinaudo CD Masignani V Mora M Scarselli M Tettelin H Brettoni C Iacobini ET Rosini R D'Agostino N Miorin L Buccato S Mariani M Galli G Nogarotto R Nardi-Dei V Nardi Dei V Vegni F Fraser C Mancuso G Teti G Madoff LC Paoletti LC Rappuoli R Kasper DL Telford JL Grandi G 《Science (New York, N.Y.)》2005,309(5731):148-150
Group B Streptococcus (GBS) is a multiserotype bacterial pathogen representing a major cause of life-threatening infections in newborns. To develop a broadly protective vaccine, we analyzed the genome sequences of eight GBS isolates and cloned and tested 312 surface proteins as vaccines. Four proteins elicited protection in mice, and their combination proved highly protective against a large panel of strains, including all circulating serotypes. Protection also correlated with antigen accessibility on the bacterial surface and with the induction of opsonophagocytic antibodies. Multigenome analysis and screening described here represent a powerful strategy for identifying potential vaccine candidates against highly variable pathogens. 相似文献
952.
Perlo J Demas V Casanova F Meriles CA Reimer J Pines A Blümich B 《Science (New York, N.Y.)》2005,308(5726):1279
We report construction of a portable nuclear magnetic resonance sensor with a single-sided open probe design. The resulting magnetic field inhomogeneity is compensated by a pulse sequence that takes advantage of parallel inhomogeneity in the applied radio frequency field. We can thereby acquire fluorine-19 spectra of liquid fluorocarbons with 8 parts per million resolution, surmounting the long-standing obstacle of obtaining chemical shift information with open probe instruments. 相似文献
953.
Cell therapy of alpha-sarcoglycan null dystrophic mice through intra-arterial delivery of mesoangioblasts 总被引:1,自引:0,他引:1
Sampaolesi M Torrente Y Innocenzi A Tonlorenzi R D'Antona G Pellegrino MA Barresi R Bresolin N De Angelis MG Campbell KP Bottinelli R Cossu G 《Science (New York, N.Y.)》2003,301(5632):487-492
Preclinical or clinical trials for muscular dystrophies have met with modest success, mainly because of inefficient delivery of viral vectors or donor cells to dystrophic muscles. We report here that intra-arterial delivery of wild-type mesoangioblasts, a class of vessel-associated stem cells, corrects morphologically and functionally the dystrophic phenotype of virtually all downstream muscles in adult immunocompetent alpha-sarcoglycan (alpha-SG) null mice, a model organism for limb-girdle muscular dystrophy. When mesoangioblasts isolated from juvenile dystrophic mice and transduced with a lentiviral vector expressing alpha-SG were injected into the femoral artery of dystrophic mice, they reconstituted skeletal muscle in a manner similar to that seen in wild-type cells. The success of this protocol was mainly due to widespread distribution of donor stem cells through the capillary network, a distinct advantage of this strategy over previous approaches. 相似文献
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955.
Alatalo RV Aragón S Avilés JM Barbosa A Gomes CB Cadée N Christe P Cuervo JJ Díaz M Erritzøe J Galeotti P Garamszegi LZ Gil D Gontard-Danek M Legendre S Martin TE Martínez J Martín-Vivaldi M Martínez JG Merino S Moreno J Mousseau T Ninni P Petrie M Pulido F Rubolini D Saino N Soler JJ Soler M Spottiswoode C Szép T Thornhill R Zamora C Sacchi R 《Science (New York, N.Y.)》2004,303(5664):1612
956.
957.
Stransky N Egloff AM Tward AD Kostic AD Cibulskis K Sivachenko A Kryukov GV Lawrence MS Sougnez C McKenna A Shefler E Ramos AH Stojanov P Carter SL Voet D Cortés ML Auclair D Berger MF Saksena G Guiducci C Onofrio RC Parkin M Romkes M Weissfeld JL Seethala RR Wang L Rangel-Escareño C Fernandez-Lopez JC Hidalgo-Miranda A Melendez-Zajgla J Winckler W Ardlie K Gabriel SB Meyerson M Lander ES Getz G Golub TR Garraway LA Grandis JR 《Science (New York, N.Y.)》2011,333(6046):1157-1160
Head and neck squamous cell carcinoma (HNSCC) is a common, morbid, and frequently lethal malignancy. To uncover its mutational spectrum, we analyzed whole-exome sequencing data from 74 tumor-normal pairs. The majority exhibited a mutational profile consistent with tobacco exposure; human papillomavirus was detectable by sequencing DNA from infected tumors. In addition to identifying previously known HNSCC genes (TP53, CDKN2A, PTEN, PIK3CA, and HRAS), our analysis revealed many genes not previously implicated in this malignancy. At least 30% of cases harbored mutations in genes that regulate squamous differentiation (for example, NOTCH1, IRF6, and TP63), implicating its dysregulation as a major driver of HNSCC carcinogenesis. More generally, the results indicate the ability of large-scale sequencing to reveal fundamental tumorigenic mechanisms. 相似文献
958.
Kunkes EL Simonetti DA West RM Serrano-Ruiz JC Gärtner CA Dumesic JA 《Science (New York, N.Y.)》2008,322(5900):417-421
It is imperative to develop more efficient processes for conversion of biomass to liquid fuels, such that the cost of these fuels would be competitive with the cost of fuels derived from petroleum. We report a catalytic approach for the conversion of carbohydrates to specific classes of hydrocarbons for use as liquid transportation fuels, based on the integration of several flow reactors operated in a cascade mode, where the effluent from the one reactor is simply fed to the next reactor. This approach can be tuned for production of branched hydrocarbons and aromatic compounds in gasoline, or longer-chain, less highly branched hydrocarbons in diesel and jet fuels. The liquid organic effluent from the first flow reactor contains monofunctional compounds, such as alcohols, ketones, carboxylic acids, and heterocycles, that can also be used to provide reactive intermediates for fine chemicals and polymers markets. 相似文献
959.
Kaiser CM Goldman DH Chodera JD Tinoco I Bustamante C 《Science (New York, N.Y.)》2011,334(6063):1723-1727
Proteins are synthesized by the ribosome and generally must fold to become functionally active. Although it is commonly assumed that the ribosome affects the folding process, this idea has been extremely difficult to demonstrate. We have developed an experimental system to investigate the folding of single ribosome-bound stalled nascent polypeptides with optical tweezers. In T4 lysozyme, synthesized in a reconstituted in vitro translation system, the ribosome slows the formation of stable tertiary interactions and the attainment of the native state relative to the free protein. Incomplete T4 lysozyme polypeptides misfold and aggregate when free in solution, but they remain folding-competent near the ribosomal surface. Altogether, our results suggest that the ribosome not only decodes the genetic information and synthesizes polypeptides, but also promotes efficient de novo attainment of the native state. 相似文献
960.