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An index to assess the health and benefits of the global ocean   总被引:15,自引:0,他引:15  
The ocean plays a critical role in supporting human well-being, from providing food, livelihoods and recreational opportunities to regulating the global climate. Sustainable management aimed at maintaining the flow of a broad range of benefits from the ocean requires a comprehensive and quantitative method to measure and monitor the health of coupled human–ocean systems. We created an index comprising ten diverse public goals for a healthy coupled human–ocean system and calculated the index for every coastal country. Globally, the overall index score was 60 out of 100 (range 36–86), with developed countries generally performing better than developing countries, but with notable exceptions. Only 5% of countries scored higher than 70, whereas 32% scored lower than 50. The index provides a powerful tool to raise public awareness, direct resource management, improve policy and prioritize scientific research.  相似文献   
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Recombination, together with mutation, gives rise to genetic variation in populations. Here we leverage the recent mixture of people of African and European ancestry in the Americas to build a genetic map measuring the probability of crossing over at each position in the genome, based on about 2.1 million crossovers in 30,000 unrelated African Americans. At intervals of more than three megabases it is nearly identical to a map built in Europeans. At finer scales it differs significantly, and we identify about 2,500 recombination hotspots that are active in people of West African ancestry but nearly inactive in Europeans. The probability of a crossover at these hotspots is almost fully controlled by the alleles an individual carries at PRDM9 (P?value 相似文献   
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Résumé L'action de la nicotine monométhyliodine (NMI) sur la sécrétion gastrique basique et sur les concentrations de choline de cervelles, d'acétylcholine et de nicotine et sur l'activité de la transacétylcholinestérase a été étudiée chez des rats. Le NMI, sel quaternaire de nicotine, qui ne traverse pas la barrière hématoencéphalique, a été administré dans de la gélatine à 6% en dosage sous-cutané de 1000 g/ml/kg/jour pendant 14 jours. Le NMI n'a pas changé de paramètres et aucune trace de nicotine n'a été découverte dans les homogénates de cervelles complètes.  相似文献   
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Zusammenfassung Im Serum und in Bronchialsekreten von Hunden konnten Antikörper gegen DNP, die über die Atmungswege mit DNP-Proteinkonjugaten immunisiert worden waren, nachgewiesen werden. Die Titer der beobachteten spezifischen Antikörper waren für eine detaillierte Analyse zu niedrig.

This work was supported by National Institutes of Health Training Grant No. 5TI AI0128-09.  相似文献   
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The study of macromolecular complexes by quantitative proteomics   总被引:1,自引:0,他引:1  
We describe a generic strategy for determining the specific composition, changes in the composition, and changes in the abundance of protein complexes. It is based on the use of isotope-coded affinity tag (ICAT) reagents and mass spectrometry to compare the relative abundances of tryptic peptides derived from suitable pairs of purified or partially purified protein complexes. In a first application, the genuine protein components of a large RNA polymerase II (Pol II) preinitiation complex (PIC) were distinguished from a background of co-purifying proteins by comparing the relative abundances of peptides derived from a control sample and the specific complex that was purified from nuclear extracts by a single-step promoter DNA affinity procedure. In a second application, peptides derived from immunopurified STE12 protein complexes isolated from yeast cells in different states were used to detect quantitative changes in the abundance of the complexes, and to detect dynamic changes in the composition of the samples. The use of quantitative mass spectrometry to guide identification of specific complex components in partially purified samples, and to detect quantitative changes in the abundance and composition of protein complexes, provides the researcher with powerful new tools for the comprehensive analysis of macromolecular complexes.  相似文献   
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Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disorder characterized by features reminiscent of marked premature ageing. Here, we present evidence of mutations in lamin A (LMNA) as the cause of this disorder. The HGPS gene was initially localized to chromosome 1q by observing two cases of uniparental isodisomy of 1q-the inheritance of both copies of this material from one parent-and one case with a 6-megabase paternal interstitial deletion. Sequencing of LMNA, located in this interval and previously implicated in several other heritable disorders, revealed that 18 out of 20 classical cases of HGPS harboured an identical de novo (that is, newly arisen and not inherited) single-base substitution, G608G(GGC > GGT), within exon 11. One additional case was identified with a different substitution within the same codon. Both of these mutations result in activation of a cryptic splice site within exon 11, resulting in production of a protein product that deletes 50 amino acids near the carboxy terminus. Immunofluorescence of HGPS fibroblasts with antibodies directed against lamin A revealed that many cells show visible abnormalities of the nuclear membrane. The discovery of the molecular basis of this disease may shed light on the general phenomenon of human ageing.  相似文献   
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Huntington disease is caused by the expansion of a polyglutamine repeat in the Huntingtin protein (Htt) that leads to degeneration of neurons in the central nervous system and the appearance of visible aggregates within neurons. We have developed and tested suppressor polypeptides that bind mutant Htt and interfere with the process of aggregation in cell culture. In a Drosophila model, the most potent suppressor inhibits both adult lethality and photoreceptor neuron degeneration. The appearance of aggregates in photoreceptor neurons correlates strongly with the occurrence of pathology, and expression of suppressor polypeptides delays and limits the appearance of aggregates and protects photoreceptor neurons. These results suggest that targeting the protein interactions leading to aggregate formation may be beneficial for the design and development of therapeutic agents for Huntington disease.  相似文献   
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