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71.
Serum samples from 191 ostriches (Struthio camelus) in Japan were tested for antibodies to Newcastle disease virus (NDV) and avian influenza virus (AIV). Twenty-two (12%) contained NDV-specific neutralizing antibodies by a virus-neutralization (VN) test without vaccination. Antibodies to AIV were not detected in the any sera by an agar gel precipitation test. Seven serum samples that had vaccinated with live NDV by eye drop were all positive by the VN test at 1 month post vaccination. A haemagglutination inhibition (HI) test for NDV seemed not to be suitable for ostriches because of non-specific agglutination of chicken red blood cells. No haemagglutinating viruses were isolated. This is the first report on detection of antibodies against NDV in ostriches in Japan.  相似文献   
72.
Lipoxygenase was purified homogeneously from cups of Pleurotus ostreatus by Sephacryl S-400 HR gel filtration, Dyematrex Green A affinity, and DEAE-Toyopearl 650M ion-exchange chromatographies. The molecular weight of the enzyme was estimated to be 67,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 66,000 by gel filtration; the isoelectric point was pH 5.1. The optimum pH and temperature of the enzymatic activity were 8.0 and 25 degrees C, respectively. The enzyme contained non-heme iron, and a thiol group seemed to be involved in its activity. The K(m), V(max), and k(cat) values of the enzyme for linoleic acid were 0.13 mM, 23.4 micromol.min(-1).mg(-1), and 25.7 s(-1), respectively. The enzyme showed high specificity toward linoleic acid. When linoleic acid was incubated with the enzyme, 13-hydroperoxy-9Z,11E-octadecadienoic acid was found to be the main oxidative product.  相似文献   
73.
The present study was carried out to analyze the factors that affected the growth of sugar beet in four different soil types by using concrete-framed plots as follows: soil acidity (soil pH, exchange acidity y 1) and nitrification of fertilizer introduced by row application. Comparison of the value of the exchange acidity y 1 of the four soil types with the pH value adjusted to the same level (pH 5.1) revealed that the Humic Gray Upland soil displayed the highest y 1 value (y 1: 18.0), followed by the Humic Volcanogenous Regosol (y 1: 6.9), Haplic Brown Lowland soil (y 1: 5.3), and Low-humic Andosol (y 1: 2.2). Al release to the soil solution was considered to occur at soil pH values of 4.8 and lower except in the Low-humic Andosol. Al concentration in the soil solution of the Low-humic Andosol was substantially lower than that of the other soils. On the other hand, the soil pH value decreased temporarily by nitrification of the fertilizer introduced by row application, especially in the Humic Gray Upland soil. In this case, the soil pH value became lower than 4.8 for a time. At this pH level, Al release to the soil solution was assumed to occur. As described above, the soils displayed different properties in terms of soil acidity. In the four soils, although the growth of sugar beet was significantly related to both soil pH and exchange acidity y 1 values before sowing, these relations were not strictly valid. On the other hand, the linear correlation coefficients of the relationships between the growth of sugar beet (leaf length) and NO3-N content in rows were higher than those of the soil pH and exchange acidity y 1. No appreciable variation associated with the differences in the soil types was observed in this relation. Furthermore, the values of both soil pH and exchange acidity y 1 were closely related to the NO3-N content in rows and the relationship between the NO3-N content and y 1 value appeared to be somewhat closer than that with the soil pH. These closer relations had two important implications. Firstly, NO3-N content reflected the nitrogen nutrient conditions. NO3-N promoted the growth of sugar beet directly. Secondly, the NO3-N content was affected by the soil acidity, which is expressed by the value of the exchange acidity y 1. Low NO3-N content indicated indirectly the toxicity of soil acidity to sugar beet growth. It was thus suggested that in the present study, nitrification of the fertilizer expressed by the NO3-N content was a beneficial factor for the growth of sugar beet regardless of the soil types. Finally, to promote the nitrification of fertilizer and to minimize the Al toxicity enhanced by the decrease of the soil pH associated with nitrification, it is important to avoid low values for the soil pH.  相似文献   
74.
We have performed an in situ test of the iron limitation hypothesis in the subarctic North Pacific Ocean. A single enrichment of dissolved iron caused a large increase in phytoplankton standing stock and decreases in macronutrients and dissolved carbon dioxide. The dominant phytoplankton species shifted after the iron addition from pennate diatoms to a centric diatom, Chaetoceros debilis, that showed a very high growth rate, 2.6 doublings per day. We conclude that the bioavailability of iron regulates the magnitude of the phytoplankton biomass and the key phytoplankton species that determine the biogeochemical sensitivity to iron supply of high-nitrate, low-chlorophyll waters.  相似文献   
75.
Regenerative therapy using bone marrow stromal cells (BMSCs) has begun to be clinically applied in humans and dogs for neurological disorders such as spinal cord injury. Under appropriate conditions in vitro, BMSCs differentiate into neuronal cells, which may improve the effects of regenerative therapy. In this study, we evaluated canine neuron-like cells (NLCs) derived from BMSCs. We speculated on their suitability for neuro-transplantation from the point of view of their morphological features, long-term viability, abundant availability, and ability to be subcultured. Canine NLCs were differentiated as follows: third-passage BMSCs were maintained in pre-induction medium containing 2-mercaptoethanol and dimethylsulfoxide for 5 h, and then cells were transferred to neuronal induction medium containing fetal bovine serum, basic fibroblast growth factor, epidermal growth factor, dibutyryl cyclic AMP, and isobutylmethylxanthine for 7 or 14 days. Canine NLCs fulfilled the transplantation criteria and expressed markers of both immature neurons (nestin, 84.7 %) and mature neuronal cells (microtubule-associated protein-2, 95.7 %; βIII-tubulin protein, 12.9 %; glial fibrillary acidic protein, 9.2 %). These results suggest that canine BMSCs can be induced to differentiate into neuronal cells and may be suitable for neuro-transplantation. This study may provide information for improving cellular therapy for neurological diseases.  相似文献   
76.
Quercus serrata Thunb. ex Murray is a widespread deciduous oak in China, the Korean Peninsula, and Japan, and a strong isoprene emitter. Establishing accurate inventories of this species and estimating net carbon budgets, including biogenic volatile organic compounds (BVOC), necessitates detailed evaluation of BVOC emission and oxidation characteristics. Emissions of isoprene, the most abundant BVOC, presumably contribute to atmospheric chemistry through the formation of photochemical oxidants and secondary organic aerosols. We built an isoprene flux monitoring system to simultaneously reveal characteristics of the flux and fate of isoprene at multiple locations in Q. serrata forests. We used proton transfer reaction mass spectrometry (PTR-MS) and an automated closed chamber to measure isoprene emissions from soil and leaves in a warm-temperate Q. serrata forest. We used a relaxed eddy accumulation system with PTR-MS to simultaneously measure the canopy flux. In continuous foliage chamber measurements, we observed daily variations of isoprene emissions and continuous nocturnal emissions from leaves. Nocturnal emissions exceeded 25 % of total daily leaf emissions and were relatively high at sunset and low at sunrise. These results suggest that nocturnal emissions from mature trees may not be negligible. When leaf emissions were high in the daytime, the canopy isoprene flux tended to plateau at an upper limit. Observations of isoprene concentrations and gradients suggest that the plateau was caused by acceleration of isoprene oxidation, and sequential formation of secondary organic aerosols may occur near the leaf just after emission. Elucidation of these linkages may require continuous field measurements with a simultaneous multi-flux monitoring system.  相似文献   
77.
We examined the effects of deep percolation on dissolved inorganic nitrogen (DIN) exports from two adjacent weathered granite headwater catchments with different deep percolations of water in the Kiryu Experimental Watershed (KEW), Japan. The DIN output in streamflow was estimated from a regression equation between stream discharge and the DIN load, determined from both monthly sampling data and event-based sampling data. The range of deep percolation of DIN was estimated by multiplying observed DIN concentrations in bedrock groundwater by the deep percolation of water estimated from an annual water budget analysis. We found that the deep percolation of DIN corresponded to 34–76 % and ?18 to 8 % of the total DIN output in catchments where the deep percolation of water was 37–45 % and ?6 to 3 % of annual precipitation, respectively. This means that the deep percolation of DIN is not negligible when estimating the total output of DIN in the former catchment. Moreover, the fact that deep percolating water from upper catchments discharged into a lower catchment in KEW suggests that deep percolation of DIN affects downstream N budgets. Therefore, it is important to account for the deep percolation of DIN when evaluating N budgets in forested headwater catchments as well as downstream catchments.  相似文献   
78.
The effect of vinclozolin (VCZ), used as a fungicide and known to have anti-androgenic effects on spermatogenesis and gene expression in the male rat testis was investigated. In Experiment 1, VCZ (100 mg/kg/day) or flutamide (FM, 25 mg/kg/day) was orally administered to male Holzman rats for six days. 8 days after the last administration (D8), a drastic increase in intratesticular testosterone was detected in FM (4.2-fold over control) but not in VCZ treated animals, whereas on D36 post-administration, both groups showed similar levels. Significant decreases in daily sperm production were seen in both VCZ and FM-treated rats on D36. Semiquantitative RT-PCR analysis with testicular and pituitary mRNAs on D8 revealed that LHbeta and FSHbeta mRNAs were increased in the pituitary by VCZ, as well as by FM. Among the four testicular steroidogenic enzyme genes, cytochrome P450 side chain cleavage (P450scc) and cytochrome P450 17alpha/C(17-20) lyase (P450c17) mRNAs were significantly increased, whereas 17beta-hydroxysteroid dehydrogenase type III (17betaHSD) mRNA was not changed. A significant increase in 3beta-hydroxysteroid dehydrogenase type I (3betaHSD) and a decrease in androgen receptor (AR) mRNA were observed only in FM treated rats. Immunohistochemistry demonstrated intense staining of P450scc in the interstitial cells of VCZ-treated testis on D8. In Experiment 2, hormone levels were measured at 1, 3, 6, 12 and 24 hours after VCZ (100 mg/kg) administration to Sprague-Dawley rats. Serum LH level remained constant for the first 3 hours and started to increase at 6 hrs. In contrast, serum and intratesticular testosterone levels increased 2-fold at 1 hr and maintained the level until 24 hrs. P450c17 mRNA level was 2-fold increased at all periods, whereas no obvious changes were detected in the other steroidogenic enzyme genes. Although not statistically significant, AR mRNA level increased 2-fold, 3 hrs after VCZ administration. These results indicate that VCZ affects the pituitary in a similar manner as FM, but functions differently on testicular gene expression.  相似文献   
79.
80.
The first case of human babesiosis was reported in Japan. The epidemiology of this disease in Japanese nature remains unclear. In this study, 97 common field mice captured in Hokkaido, Japan, were examined. Blood specimens absorbed onto filter papers were eluted and tested by nested PCR using specific primers for the B. microti nuclear small subunit rRNA genome. Twenty-three percent (11/47) of Apodemus speciosus and four percent (2/50) of Clethrionomys rufocanus were positive. The 159-bp primary sequences of PCR products tested exhibited 97.5% and 96.8% homology with those of the human isolate in Japan and of U.S. strains of B. microti, respectively.  相似文献   
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