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11.
In the cores of some clusters of galaxies the hot intracluster plasma is dense enough that it should cool radiatively in the cluster's lifetime, leading to continuous 'cooling flows' of gas sinking towards the cluster centre, yet no such cooling flow has been observed. The low observed star-formation rates and cool gas masses for these 'cool-core' clusters suggest that much of the cooling must be offset by feedback to prevent the formation of a runaway cooling flow. Here we report X-ray, optical and infrared observations of the galaxy cluster SPT-CLJ2344-4243 (ref. 11) at redshift z = 0.596. These observations reveal an exceptionally luminous (8.2?×?10(45)?erg?s(-1)) galaxy cluster that hosts an extremely strong cooling flow (around 3,820 solar masses a year). Further, the central galaxy in this cluster appears to be experiencing a massive starburst (formation of around 740 solar masses a year), which suggests that the feedback source responsible for preventing runaway cooling in nearby cool-core clusters may not yet be fully established in SPT-CLJ2344-4243. This large star-formation rate implies that a significant fraction of the stars in the central galaxy of this cluster may form through accretion of the intracluster medium, rather than (as is currently thought) assembling entirely via mergers.  相似文献   
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Summary Thin-layer chromatographic separation and bioassay of arginin-vasotocin and ichtyotocin of hypophyseal and preoptic nucleus extracts from North Sea eels show that the hypophysis is much richer in arginin-vasotocin than in ichtyotocin. Analogous results have been observed in the preoptic nucleus fractions.

Avec la collaboration technique de M. G.Hoeltzel.  相似文献   
14.
We used an exome-sequencing strategy and identified an allelic series of NOTCH2 mutations in Hajdu-Cheney syndrome, an autosomal dominant multisystem disorder characterized by severe and progressive bone loss. The Hajdu-Cheney syndrome mutations are predicted to lead to the premature truncation of NOTCH2 with either disruption or loss of the C-terminal proline-glutamate-serine-threonine-rich proteolytic recognition sequence, the absence of which has previously been shown to increase Notch signaling.  相似文献   
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A Kind of Systems Methodology——The SPIPRO Principle   总被引:1,自引:0,他引:1  
This paper deals with the Self-Increasing-Difficulty system (SIDIS) separated from general systems, with emphasis on the relevant methodology based on the Spiral Combining Propulsion Principle (SPIPRO principle in short). The system feature and its causative factors are analysed, and the implications and mechanism of the SPIPRO principle are discussed. Finally, the application possibilities of this methodology are illustrated with some examples.  相似文献   
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Recently, a class of protein antigens of high relative molecular mass (Mt) which can induce protective immunity against blood-stage malaria has been identified. In Plasmodium falciparum the protein has a Mr of approximately 195,000 (P195). It is the precursor of three proteins of Mr 83,000 (83K), 42K and 19K which are the major surface antigens of merozoites; thus it may also be useful for immunization against P. falciparum. Three studies describing the isolation of single short complementary DNA clones for part of the P195 gene sequence have been reported. Here we describe the complete structure of the P195 gene determined from further DNA clones, its organization within genomic DNA and the location of the specific processing fragments within the primary amino-acid sequence.  相似文献   
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A proteomic view of the Plasmodium falciparum life cycle   总被引:43,自引:0,他引:43  
The completion of the Plasmodium falciparum clone 3D7 genome provides a basis on which to conduct comparative proteomics studies of this human pathogen. Here, we applied a high-throughput proteomics approach to identify new potential drug and vaccine targets and to better understand the biology of this complex protozoan parasite. We characterized four stages of the parasite life cycle (sporozoites, merozoites, trophozoites and gametocytes) by multidimensional protein identification technology. Functional profiling of over 2,400 proteins agreed with the physiology of each stage. Unexpectedly, the antigenically variant proteins of var and rif genes, defined as molecules on the surface of infected erythrocytes, were also largely expressed in sporozoites. The detection of chromosomal clusters encoding co-expressed proteins suggested a potential mechanism for controlling gene expression.  相似文献   
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Summary A kinetic study of hormonal inactivation in the presence of sodium thioglycolate was carried out using the rat uterus bioassay. In all cases we observed a total inactivation of the hormonal activities, whether the uterine horn is in the presence or not of magnesium. The hormones under consideration divide into 2 groups: the arginine-vasotocin group (rapidly inactivated), and the ichtyotocin and oxytocin group (more slowly inactivated). But, in all cases the rate of inactivation is linear.

Avec la collaboration technique de Mr.G. Hoeltzel.  相似文献   
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