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61.
Cornelia de Lange syndrome is a multisystem developmental disorder characterized by facial dysmorphisms, upper limb abnormalities, growth delay and cognitive retardation. Mutations in the NIPBL gene, a component of the cohesin complex, account for approximately half of the affected individuals. We report here that mutations in SMC1L1 (also known as SMC1), which encodes a different subunit of the cohesin complex, are responsible for CdLS in three male members of an affected family and in one sporadic case.  相似文献   
62.
Summary Tokophrya infusionum, a suctorian, is deprived of a mouth opening. The uptake of ferritin from the medium is accomplished through pits, invaginations of the plasma membrane which are permanent structures. From the pits containing ferritin, flat vesicles are pinched off transporting the ferritin to the cytoplasm.Supported by grant AI-08989 US Public Health Service.The author acknowledges gratefully the excellent technical assistance of Mrs Sondra Lewengrub.  相似文献   
63.
Summary The influence of catecholamines on the platelet count was studied in an in vivo experimental model obtained with cannulation of the carotid and of the femoral vein. The i.v. infusion of epinephrine and l-norepinephrine induces a low drop in the platelet count and also potentiate aggregation by ADP.  相似文献   
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Riassunto Contrariamente ad altri inibitori specifici dei poliovirus che prevengono RNA-sintesi virale ed effetto citopatologico, ma non hano effetto sui danni precoci che l'infezione induce nel metabolismo cellulare, un derivato tiopirimidinico è anche capace di impedire il blocco precocem virus indotto, delle proteino-sinsteis cellulari.

This work has been supported by the Consigiio Nazionale delle Ricerche, Rome (Italy).  相似文献   
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Summary Quinic acid methyl ester, having the 1.4 and 5 hydroxy-groups suitably blocked, was condensed with the carbonilcaffeic acid chloride.Gradual hydrolysis of the condensation compound gave place to chlorogenic acid.  相似文献   
68.
Riassunto L'Autore ha studiato l'influenza della concentrazione degli ioni Ca++ e Mg++ sull'ATPasi degli atri e dei ventricoli di cuore di cavia. Tale attività è maggiore a pH 9,2 che a pH 6,8. Mentre il Ca++ influisce differenziando decisamente le attività degli atri da quelle dei ventricoli, il Mg++ accentua piuttosto una differenza tra la parte destra e la sinistra. Il calore distrugge quasi completamente l'attività enzimatica dopo una permanenza a 60° per 20 min.  相似文献   
69.
Genome sequencing in microfabricated high-density picolitre reactors   总被引:21,自引:0,他引:21  
The proliferation of large-scale DNA-sequencing projects in recent years has driven a search for alternative methods to reduce time and cost. Here we describe a scalable, highly parallel sequencing system with raw throughput significantly greater than that of state-of-the-art capillary electrophoresis instruments. The apparatus uses a novel fibre-optic slide of individual wells and is able to sequence 25 million bases, at 99% or better accuracy, in one four-hour run. To achieve an approximately 100-fold increase in throughput over current Sanger sequencing technology, we have developed an emulsion method for DNA amplification and an instrument for sequencing by synthesis using a pyrosequencing protocol optimized for solid support and picolitre-scale volumes. Here we show the utility, throughput, accuracy and robustness of this system by shotgun sequencing and de novo assembly of the Mycoplasma genitalium genome with 96% coverage at 99.96% accuracy in one run of the machine.  相似文献   
70.
Generation and annotation of the DNA sequences of human chromosomes 2 and 4   总被引:1,自引:0,他引:1  
Human chromosome 2 is unique to the human lineage in being the product of a head-to-head fusion of two intermediate-sized ancestral chromosomes. Chromosome 4 has received attention primarily related to the search for the Huntington's disease gene, but also for genes associated with Wolf-Hirschhorn syndrome, polycystic kidney disease and a form of muscular dystrophy. Here we present approximately 237 million base pairs of sequence for chromosome 2, and 186 million base pairs for chromosome 4, representing more than 99.6% of their euchromatic sequences. Our initial analyses have identified 1,346 protein-coding genes and 1,239 pseudogenes on chromosome 2, and 796 protein-coding genes and 778 pseudogenes on chromosome 4. Extensive analyses confirm the underlying construction of the sequence, and expand our understanding of the structure and evolution of mammalian chromosomes, including gene deserts, segmental duplications and highly variant regions.  相似文献   
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