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81.
Conditions of the colour change of prodigiosin 总被引:1,自引:0,他引:1
82.
A. K. Allen 《Cellular and molecular life sciences : CMLS》1968,24(4):415-415
Zusammenfassung Eine einfache neue Methode für die Herstellung von Serine-Äthanolamin-Phosphat, einem natürlichen Phosphorsäurediester, wird entwickelt. Sie benützt die Einwirkung von Äthelinimin auf Serinephosphat und eignet sich besonders für die Herstellung von kleineren Mengen radioaktiver Verbindungen. Auf eine mögliche ähnliche Reaktion zwischen Äthelinimin und der Serinephosphatgruppe von Proteinen wird hingewiesen. 相似文献
83.
Immunotherapeutic suppression in transplantable solid tumours 总被引:2,自引:0,他引:2
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Carlton JM Angiuoli SV Suh BB Kooij TW Pertea M Silva JC Ermolaeva MD Allen JE Selengut JD Koo HL Peterson JD Pop M Kosack DS Shumway MF Bidwell SL Shallom SJ van Aken SE Riedmuller SB Feldblyum TV Cho JK Quackenbush J Sedegah M Shoaibi A Cummings LM Florens L Yates JR Raine JD Sinden RE Harris MA Cunningham DA Preiser PR Bergman LW Vaidya AB van Lin LH Janse CJ Waters AP Smith HO White OR Salzberg SL Venter JC Fraser CM Hoffman SL Gardner MJ Carucci DJ 《Nature》2002,419(6906):512-519
Species of malaria parasite that infect rodents have long been used as models for malaria disease research. Here we report the whole-genome shotgun sequence of one species, Plasmodium yoelii yoelii, and comparative studies with the genome of the human malaria parasite Plasmodium falciparum clone 3D7. A synteny map of 2,212 P. y. yoelii contiguous DNA sequences (contigs) aligned to 14 P. falciparum chromosomes reveals marked conservation of gene synteny within the body of each chromosome. Of about 5,300 P. falciparum genes, more than 3,300 P. y. yoelii orthologues of predominantly metabolic function were identified. Over 800 copies of a variant antigen gene located in subtelomeric regions were found. This is the first genome sequence of a model eukaryotic parasite, and it provides insight into the use of such systems in the modelling of Plasmodium biology and disease. 相似文献
87.
Van Eerdewegh P Little RD Dupuis J Del Mastro RG Falls K Simon J Torrey D Pandit S McKenny J Braunschweiger K Walsh A Liu Z Hayward B Folz C Manning SP Bawa A Saracino L Thackston M Benchekroun Y Capparell N Wang M Adair R Feng Y Dubois J FitzGerald MG Huang H Gibson R Allen KM Pedan A Danzig MR Umland SP Egan RW Cuss FM Rorke S Clough JB Holloway JW Holgate ST Keith TP 《Nature》2002,418(6896):426-430
Asthma is a common respiratory disorder characterized by recurrent episodes of coughing, wheezing and breathlessness. Although environmental factors such as allergen exposure are risk factors in the development of asthma, both twin and family studies point to a strong genetic component. To date, linkage studies have identified more than a dozen genomic regions linked to asthma. In this study, we performed a genome-wide scan on 460 Caucasian families and identified a locus on chromosome 20p13 that was linked to asthma (log(10) of the likelihood ratio (LOD), 2.94) and bronchial hyperresponsiveness (LOD, 3.93). A survey of 135 polymorphisms in 23 genes identified the ADAM33 gene as being significantly associated with asthma using case-control, transmission disequilibrium and haplotype analyses (P = 0.04 0.000003). ADAM proteins are membrane-anchored metalloproteases with diverse functions, which include the shedding of cell-surface proteins such as cytokines and cytokine receptors. The identification and characterization of ADAM33, a putative asthma susceptibility gene identified by positional cloning in an outbred population, should provide insights into the pathogenesis and natural history of this common disease. 相似文献
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89.
Minocycline inhibits cytochrome c release and delays progression of amyotrophic lateral sclerosis in mice 总被引:56,自引:0,他引:56
Zhu S Stavrovskaya IG Drozda M Kim BY Ona V Li M Sarang S Liu AS Hartley DM Wu DC Gullans S Ferrante RJ Przedborski S Kristal BS Friedlander RM 《Nature》2002,417(6884):74-78
Minocycline mediates neuroprotection in experimental models of neurodegeneration. It inhibits the activity of caspase-1, caspase-3, inducible form of nitric oxide synthetase (iNOS) and p38 mitogen-activated protein kinase (MAPK). Although minocycline does not directly inhibit these enzymes, the effects may result from interference with upstream mechanisms resulting in their secondary activation. Because the above-mentioned factors are important in amyotrophic lateral sclerosis (ALS), we tested minocycline in mice with ALS. Here we report that minocycline delays disease onset and extends survival in ALS mice. Given the broad efficacy of minocycline, understanding its mechanisms of action is of great importance. We find that minocycline inhibits mitochondrial permeability-transition-mediated cytochrome c release. Minocycline-mediated inhibition of cytochrome c release is demonstrated in vivo, in cells, and in isolated mitochondria. Understanding the mechanism of action of minocycline will assist in the development and testing of more powerful and effective analogues. Because of the safety record of minocycline, and its ability to penetrate the blood-brain barrier, this drug may be a novel therapy for ALS. 相似文献
90.
Rodríguez J Tintoré J Allen JT Blanco JM Gomis D Reul A Ruiz J Rodríguez V Echevarría F Jiménez-Gómez F 《Nature》2001,410(6826):360-363
Phytoplankton size structure is acknowledged as a fundamental property determining energy flow through 'microbial' or 'herbivore' pathways. The balance between these two pathways determines the ability of the ecosystem to recycle carbon within the upper layer or to export it to the ocean interior. Small cells are usually characteristic of oligotrophic, stratified ocean waters, in which regenerated ammonium is the only available form of inorganic nitrogen and recycling dominates. Large cells seem to characterize phytoplankton in which inputs of nitrate enter the euphotic layer and exported production is higher. But the size structure of phytoplankton may depend more directly on hydrodynamical forces than on the source of available nitrogen. Here we present an empirical model that relates the magnitude of mesoscale vertical motion to the slope of the size-abundance spectrum of phytoplankton in a frontal ecosystem. Our model indicates that the relative proportion of large cells increases with the magnitude of the upward velocity. This suggests that mesoscale vertical motion-a ubiquitous feature of eddies and unstable fronts-controls directly the size structure of phytoplankton in the ocean. 相似文献