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51.
Summary Halothane anesthesia was found to be hepatotoxic in the rat, as demonstrated by a significant elevation of serum xanthine oxidase (SXO) level. SXO appeared to be a more sensitive marker of liver damage than serum, glutamic oxalacetic transaminsa. SXO was found to be elevated also following exposure to relative hypoxia.  相似文献   
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Résumé Dans les travaux de divers laboratoires on peut lire que l'acide-amino-butyrique (GABA) existe dans la salive humaine. Nos récents examens chromatographiques ont mis en évidence que cet acide avait été identifié par erreur et qu'il représente en fait l'acide-amino-valérique (DAVA), un constituant de la salive provenant de l'action bacterienne.  相似文献   
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Control,exploitation and tolerance of intracellular noise   总被引:41,自引:0,他引:41  
Rao CV  Wolf DM  Arkin AP 《Nature》2002,420(6912):231-237
Noise has many roles in biological function, including generation of errors in DNA replication leading to mutation and evolution, noise-driven divergence of cell fates, noise-induced amplification of signals, and maintenance of the quantitative individuality of cells. Yet there is order to the behaviour and development of cells. They operate within strict parameters and in many cases this behaviour seems robust, implying that noise is largely filtered by the system. How can we explain the use, rejection and sensitivity to noise that is found in biological systems? An exploration of the sources and consequences of noise calls for the use of stochastic models.  相似文献   
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Within a species, home-range size can vary due to factors such as sex, mass, age, and breeding condition of individuals as well as habitat type, food availability, population density, and season. The objectives of this study were to estimate home ranges of deer mice ( Peromyscus maniculatus ) in sage-steppe habitat and to test the hypothesis that several factors (sex, mass, reproductive status, and seasonality) affect home-range size. We also tested the hypothesis that deer mice exhibit home-range fidelity over time. Passive integrated transponder (PIT) technology was used to estimate home ranges in June and September 2006. Home-range estimates varied from 360 m 2 to 5868 m 2 (65 individuals, 753 observations). Home-range size increased by approximately 60% from June to September. Besides seasonality, none of the other predictors of home range were informative in explaining the variation in home range. Deer mice recaptured in September (3 months after initial capture) had high fidelity in home-range use (42.1% [SE = 8.4%] overlap with 74.1% [SE = 8.7%] area conserved; n = 9). All animals for which home range was estimated in both seasons retained some fraction of their June home range in September. Results support the use of combined location data collected over long periods, such as weeks or months, to estimate home range for deer mice. The results have implications for deer mouse–pathogen ecology, particularly with respect to modeling transmission of Sin Nombre virus—a pathogen that is directly transmitted by deer mice.  相似文献   
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Multiple myeloma is an incurable malignancy of plasma cells, and its pathogenesis is poorly understood. Here we report the massively parallel sequencing of 38 tumour genomes and their comparison to matched normal DNAs. Several new and unexpected oncogenic mechanisms were suggested by the pattern of somatic mutation across the data set. These include the mutation of genes involved in protein translation (seen in nearly half of the patients), genes involved in histone methylation, and genes involved in blood coagulation. In addition, a broader than anticipated role of NF-κB signalling was indicated by mutations in 11 members of the NF-κB pathway. Of potential immediate clinical relevance, activating mutations of the kinase BRAF were observed in 4% of patients, suggesting the evaluation of BRAF inhibitors in multiple myeloma clinical trials. These results indicate that cancer genome sequencing of large collections of samples will yield new insights into cancer not anticipated by existing knowledge.  相似文献   
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1. Introduction Recent advances in Information and Communication Technologies (ICT) have occurred in a number of areas includinginformation quality (Chutimaskul and Wangpipatwong 2004), strategy (Sha, Hung and Lin 2004) organization (Crowne 2004), technological change (Mitchell 2004), and utility1. Introduction Recent advances in Information and Communication Technologies (ICT) have occurred in a number of areas includinginformation quality (Chutimaskul and Wangpipatwong 2004), strateg…  相似文献   
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Physical association between MHC class I molecules and immunogenic peptides   总被引:5,自引:0,他引:5  
Antigenic peptides are presented to T lymphocytes by major histocompatibility complex (MHC) molecules. The binding of peptides to MHC class II molecules has been demonstrated directly, and is found to correlate with the ability of specific class II alleles to restrict the T-cell response to specific peptides. By comparison, a direct demonstration of a physical association between antigenic peptides and MHC class I molecules has proved difficult. A recent report shows that it is possible, however, and the three-dimensional structure of a class I MHC molecule illustrates the site where such binding must occur. Here we describe a simple assay which measures the binding of radiolabelled MHC class I molecules to peptides bound to a solid phase support. We find that class I molecules bind specifically to peptides known to be antigenic for class I-restricted cytotoxic T lymphocytes. Peptides which are recognized by cytotoxic T lymphocytes bind not only to the restricting MHC class I molecule but also to other class I molecules. Our results suggest that quantitative differences in the peptide/MHC class I interaction may influence the-pattern of MHC restriction observed in vivo.  相似文献   
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