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1.
The effect of bleeding on white muscle quality in amberjack and red sea bream was evaluated by measuring ATP-related compounds, volatile basic nitrogen (VBN), and the trimethylamine (TMA) content. The freshness was evaluated by the K value, and the degree of spoilage was elucidated by VBN and TMA. ATP was rapidly converted to ADP and AMP in the muscle and IMP was the main product of ATP degradation during iced storage. For both species, the IMP content was higher in the muscles of fish that were bled than in those unbled during iced storage. Conversely, the K value and the levels of hypoxanthine (Hx) and VBN were higher in the muscle tissue of unbled fish than in the bled tissue of both species. Similarly, the TMA content was higher in the unbled muscle tissues of both species after a week of storage.  相似文献   
2.
Transencapsidation of the Rice gall dwarf virus (RGDV) inner core by the Rice dwarf virus (RDV) outer capsid P8 protein was examined in vitro and in planta. When RGDV core particles were incubated with an extract from RDV P8-transgenic rice leaf tissue, RDV P8 encapsidated the RGDV core particles to form double-shelled virus-like particles in vitro. In contrast, when RDV P8-transgenic rice plants were inoculated with RGDV, progeny RGDV particles contained RGDV P8 but RDV P8 was not detectable in the virions. No significant differences were found in acquisition by the vector insects and subsequent transmission rates between RGDV infecting nontransgenic rice plants and those infecting RDV P8-transgenic rice plants. These results indicate that mechanisms of and/or requirements for interactions between P8 and the inner core particles of phytoreoviruses differ between in vitro and in planta.  相似文献   
3.
At Mt. Hirugatake in the Tanzawa Mountains, Kanto district, Japan, the deciduous broadleaved forests have rapidly declined. In our previous studies, we reported that the amount of soil organic matter had significantly decreased at the early and final stages of forest decline, and that the soil microbial biomass also showed a large decrease at these stages, suggesting that the composition of soil organic matter might have also changed with forest decline. To clarify the influences of forest decline on the composition of soil organic matter, the amount of humic substances, optical properties of humic acid, and the amount of soil carbohydrates in surface soils at different stages of forest decline were investigated. The amounts of humic acid and fulvic acid decreased to a lesser extent at the early and middle stages of forest decline, and showed a significant decrease at the final stage. As the amount of humin significantly decreased at the early stage, it was plausible that the distinct decrease in the total carbon content of the soil surface horizons at the early stage of forest decline was induced by the decrease in the amount of humin, and at the final stage, by the decrease in the amounts of humic acid and fulvic acid. The amount of soil carbohydrates did not change appreciably with forest decline although the soil organic matter content markedly decreased. It was suggested that most of the carbohydrates in the soil surface horizons were in a stabilized form consisting of complexes with humic substances, metals, and minerals, and would not be affected by the environmental changes associated with forest decline.  相似文献   
4.
In the present study, we identified several food-derived collagen peptides in human blood after oral ingestion of some gelatin hydrolysates. Healthy human volunteers ingested the gelatin hydrolysates (9.4-23 g) from porcine skin, chicken feet, and cartilage after 12 h of fasting. Negligible amounts of the peptide form of hydroxyproline (Hyp) were observed in human blood before the ingestion. After the oral ingestion, the peptide form of Hyp significantly increased and reached a maximum level (20-60 nmol/mL of plasma) after 1-2 h and then decreased to half of the maximum level at 4 h after the ingestion. Major constituents of food-derived collagen peptides in human serum and plasma were identified as Pro-Hyp. In addition, small but significant amounts of Ala-Hyp, Ala-Hyp-Gly, Pro-Hyp-Gly, Leu-Hyp, Ile-Hyp, and Phe-Hyp were contained.  相似文献   
5.
With high-resolution continuous gravity recordings from a regional network of superconducting gravimeters, we have detected permanent changes in gravity acceleration associated with a recent large earthquake. Detected changes in gravity acceleration are smaller than 10(-8) meters seconds(-2) (1 micro-Galileo, about 10(-9) times the surface gravity acceleration) and agree with theoretical values calculated from a dislocation model. Superconducting gravimetry can contribute to the studies of secular gravity changes associated with tectonic processes.  相似文献   
6.
Neural circuitry formation depends on the molecular control of axonal projection during development. By screening with fluorophore-assisted light inactivation in the developing mouse brain, we identified cartilage acidic protein-1B as a key molecule for lateral olfactory tract (LOT) formation and named it LOT usher substance (LOTUS). We further identified Nogo receptor-1 (NgR1) as a LOTUS-binding protein. NgR1 is a receptor of myelin-derived axon growth inhibitors, such as Nogo, which prevent neural regeneration in the adult. LOTUS suppressed Nogo-NgR1 binding and Nogo-induced growth cone collapse. A defasciculated LOT was present in lotus-deficient mice but not in mice lacking both lotus- and ngr1. These findings suggest that endogenous antagonism of NgR1 by LOTUS is crucial for normal LOT formation.  相似文献   
7.
Interaction or cross-linking between the respiratory chains of the electron transport particles of bacterial origin occurs with a mixture of active and inactive particles. Interaction between bacterial particles and liver sub-mitochondrial particles also occurs. Irradiation of the bacterial particles at 360 nanometers resulted in the destruction of quinone and consequent loss of ability of reduced nicotinamide adenine, dinucleotides to reduce cytochromes b, c(1), c, and a plus a(3). A mixture of both irradiated and untreated particles in the presence of the reduced dinucleotide resulted in the reduction of cytochromes c and a plus a(3), in an amount equivalent to the total concentration of these cytochromes in both types of particles. In contrast, the amount of cytochrome b reduced was equivalent to half the particle concentration or to that observed with the active particles alone. The rate of reduction of cytochromes c and a plus a(3) with the mixture of particles was similar to that with the active particles alone. The interaction or cross-linking between the particulate respiratory chains of bacteria or of bacterial and mammalian systems occurs after cytochrome b and before or at cytochrome c.  相似文献   
8.
In sandy fields with vegetable cultivation, fertilizer leaching may occur and it should be well-controlled. The development of a direct soil water sampler is necessary to examine solute transport and fertilizer leaching in the vadose zone, since soil water reflects timely monitoring of data more accurately than groundwater. We developed a Suction-Controlled Flux Sampler to collect infiltration soil water in a sandy soil. In the present study, we monitored fertilizer leaching in an unsaturated sandy field during the rainy season, while evaluating the sampling performance of SCFS for the sampling of infiltration water. SCFS directly collected the infiltration water effectively over a period of several months in the sandy field and recorded the Water-Collecting Efficiency from 92 to 115% under various infiltration conditions during a period of 50 d. WCE was affected by the rainfall intensity as well as by previous rainfall, which enhanced WCE. The results obtained from the use of SCFS and several sensors demonstrated that the amount of leached water remained low as long as irrigation was applied according to the cultivation manual. However, an unexpected heavy rainfall event led to fertilizer leaching. The fertilizer leaching trend was effectively monitored by several sensors inserted into the soils, while detailed analysis of the components was performed after collection by using SCFS. Direct access to infiltration water enabled to examine the infiltration process and detailed variations in the amounts of discharged anions. The sensor-equipped monitoring system together with SCFS is suitable for precise management of fertilizer and irrigation application.  相似文献   
9.
The three equine adenovirus strains isolated in different locations showed a similar cleavage pattern with HindIII and the DNA homology among the strains was confirmed by Southern blot hybridization. The three strains revealed differences in cleavage patterns with BamHI, EcoRI and PstI, suggesting the presence of DNA polymorphisms among equine adenoviruses.  相似文献   
10.
Molecule possessing ankyrin-repeats induced by lipopolysaccharide (MAIL) is known as an IkappaB protein induced after administration of bacterial lipopolysaccharide (LPS) to mice. In the present study, we cloned bovine MAIL cDNA and examined its mRNA expression in white blood cells isolated from Holstein cows. Bovine MAIL had more than 80% amino acid identities with murine and human MAILs, highly conserved ankyrin-repeat motifs and PEST-like sequences. Bovine MAIL mRNA was undetectable in isolated peripheral white blood cells, but rapidly induced (<1h) after stimulation by LPS and lipid A in vitro in a dose-dependent manner. The lipid A-induced MAIL mRNA expression was found in polymorphonuclear cells, monocytes/macrophages and total lymphocytes, but not in T-lymphocytes. MAIL mRNA was also induced in vivo in peripheral blood leukocytes of cows after intramammary injection of Escherichia coli derived from coliform mastitis. Thus, bovine MAIL, as rodent MAILs, is induced by inflammatory stimuli in specific immune cells in vitro and in vivo, suggesting a role in inflammatory responses to bacterial infection in cattle.  相似文献   
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