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31.
To assess exercise energy metabolism of forearm flexor muscles in rowers, six male student rowers and six control subjects matched for age and sex were studied using phosphorus-31 magnetic resonance spectroscopy (31P-MRS). Firstly, to adjust for the effect of differences in cross-sectional muscle area, the maximal cross-sectional area (CSAmax) of the forearm flexor muscles was estimated in each individual using magnetic resonance imaging. Multistage exercise was then carried out with an initial energy production of 1 J.cm-2 CSAmax for 1 min and an increment of 1 J.cm-2 CSAmax every minute to the point of muscle exhaustion. A series of measurements of 31P-MRS were performed every minute. The CSAmax was significantly greater in the student rowers than in the control subjects [19.8 (SD 2.2) vs 17.1 (SD 1.2) cm2, P less than 0.05]. The absolute maximal exercise intensity (J.min-1) was greater in the rowers than in the control subjects. However, the maximal exercise intensity per unit of muscle cross sectional area (J.min-1.cm-2) was not significantly different between the two groups. During mild to moderate exercise intensities, a decrease in phosphocreatine and an increase in inorganic phosphate before the onset of acidosis were significantly less in the rowers, indicating a requirement of less adenosine 5'-diphosphate to drive adenosine 5'-triphosphate production. The onset of acidosis was also significantly delayed in the rowers. No difference was observed in forearm blood flow between the two groups at the same exercise intensity (J.min-1.cm-2).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The detection of rare mutants using next generation sequencing has considerable potential for diagnostic applications. Detecting circulating tumor DNA is the foremost application of this approach. The major obstacle to its use is the high read error rate of next-generation sequencers. Rather than increasing the accuracy of final sequences, we detected rare mutations using a semiconductor sequencer and a set of anomaly detection criteria based on a statistical model of the read error rate at each error position. Statistical models were deduced from sequence data from normal samples. We detected epidermal growth factor receptor (EGFR) mutations in the plasma DNA of lung cancer patients. Single-pass deep sequencing (>100,000 reads) was able to detect one activating mutant allele in 10,000 normal alleles. We confirmed the method using 22 prospective and 155 retrospective samples, mostly consisting of DNA purified from plasma. A temporal analysis suggested potential applications for disease management and for therapeutic decision making to select epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI).  相似文献   
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The relative stereochemistry of cervicarcin, an antitumor antibiotic, was determined as shown in 1, which represents the absolute stereochemistry also.  相似文献   
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Cytochrome P-45017 alpha catalyzes both 17 alpha-hydroxylation and 17,20-side-chain cleavage in steroidogenesis and lies at a key branch point in the pathways of steroid hormone biosynthesis. To obtain information on the precise localization of P-45017 alpha in swine testis, ovary, and adrenal, we undertook the simultaneous detection of P-45017 alpha mRNA and protein by combining immunohistochemistry with in situ hybridization. In situ hybridization was performed on 4% paraformaldehyde-fixed, paraffin-embedded sections by employing either a 39-base oligomer or a cDNA insert (1.7 KB) of porcine testis P-45017 alpha as DNA probe. Immunohistochemical study was performed by employing anti-P-45017 alpha. Hybridization signals were obtained in Leydig cells of the testis, theca interna of the ovarian follicle, and zona fasciculata reticularis cells of the adrenal cortex. Oligonucleotide probing yielded lower background signal than the cDNA probe. No specific signals were obtained in seminiferous tubules of the testis, medulla, and zona glomerulosa of the adrenal, and in membrana granulosa and interstitial cells of the ovary. Hybridization signals were obtained in the cells where immunoreactivity of the enzyme was observed by immunohistochemistry, except for some Leydig cells of the testis and theca interna cells of the ovary in which only immunoreactivity but not hybridization signal was observed. The present study provided detailed information about the precise cellular localization of P-45017 alpha expression at both the protein and mRNA levels in swine adrenal glands and gonads. This approach of simultaneous immunohistochemistry and in situ hybridization analysis of steroidogenic enzymes can be applied in the future to tissues exhibiting abnormal steroid metabolism and should contribute to a better understanding of steroidogenesis.  相似文献   
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Plant pathogens are perceived by pattern recognition receptors, which are activated upon binding to pathogen-associated molecular patterns (PAMPs). Ubiquitination and vesicle trafficking have been linked to the regulation of immune signaling. However, little information exists about components of vesicle trafficking involved in immune signaling and the mechanisms that regulate them. In this study, we identified Arabidopsis thaliana Exo70B2, a subunit of the exocyst complex that mediates vesicle tethering during exocytosis, as a target of the plant U-box–type ubiquitin ligase 22 (PUB22), which acts in concert with PUB23 and PUB24 as a negative regulator of PAMP-triggered responses. We show that Exo70B2 is required for both immediate and later responses triggered by all tested PAMPs, suggestive of a role in signaling. Exo70B2 is also necessary for the immune response against different pathogens. Our data demonstrate that PUB22 mediates the ubiquitination and degradation of Exo70B2 via the 26S Proteasome. Furthermore, degradation is regulated by the autocatalytic turnover of PUB22, which is stabilized upon PAMP perception. We therefore propose a mechanism by which PUB22-mediated degradation of Exo70B2 contributes to the attenuation of PAMP-induced signaling.  相似文献   
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The gobiid fish, Trimma caudomaculatum, lives in groups. We investigated group structure, mating system and bidirectional sex change of this species. Four groups examined contained more than two males. The males were significantly larger than the females. By the observations in aquarium, the males occupied a nest and the females visited the nest for spawning. While there was no specific pair bond, the males mated with multiple females. Hence, this species establishes multi-male groups. In the experiments, four larger females had changed sex to male among 25 females. The smallest male changed to female in the group of four males.  相似文献   
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Systematic Parasitology - Recent occasional examinations of two species of eels (Anguilliformes: Anguillidae) in Japan, the Japanese eel Anguilla japonica Temminck & Schlegel from central...  相似文献   
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