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111.
The immune response during the onset of coliform mastitis in vaccinated cows was investigated by measuring lactoferrin (LF), interleukin-8 ( IL-8), and interleukin-1β (IL-1β) concentrations and somatic cell counts in 28 milk samples at the onset of acute coliform mastitis (ACM) and 73 milk samples at the onset of peracute coliform mastitis (PCM). Vaccinated ACM, unvaccinated ACM, and vaccinated PCM showed significantly higher values for LF and IL-1β levels than unvaccinated PCM (p < .01). The IL-8 concentration was lower in vaccinated PCM than in unvaccinated PCM (p < .05). There was no significant difference in somatic cell counts for each parameter. There were no significant differences in the parameters between vaccinated and unvaccinated ACM cows, or vaccinated ACM and PCM cows. From the above results, it is suggested that mastitis vaccination improved the early immune response, particularly at the onset of PCM, and played a large role in host defense against the initial infection.  相似文献   
112.
Periodic swarming by adult train millipedes Parafontaria laminata (Attems, 1909) occurs in central Japan on an 8-year cycle, and the emergence of new adults is highly predictable. Millipede biomass reaches a maximum and feeding habits change upon the emergence of adults. Larvae are geophagous while adults feed on both litter and soil. We hypothesized that the shift in the developmental stages of P. laminata influenced the carbon dynamics in the soil and conducted a field mesocosm experiment in a larch plantation forest over 2 years (1999 and 2000) using three developmental stages: sixth- and seventh-instar larvae and adults. By experimentally manipulating millipede density at four levels, we obtained the following results: larvae were geophagous, while adults consumed both litter and soil (mixed-feeding) and consequently showed stronger density effects on litter decomposition rates than larvae; adult activities in the high-density treatment increased soil microbial biomass but not at low adult densities or at the larval stages; and adults increased the carbon accumulation in soil layers especially at high densities due to their mixed-feeding on litter and soil. We determined that due to synchronized postembryonic development with high densities and changes in feeding habits, the train millipede periodically sequestered carbon in this forest.  相似文献   
113.
A field study was conducted to investigate the long-term effect of surface application of sewage sludge composts vs chemical N fertilizer on total N, total C, soluble organic C, pH, EC, microbial biomass C and N, protease activity, deaminase activity, urease activity, gross and net rates of N mineralization and nitrification, CO2 evolution, and N2O production. Soil samples were taken from five depths (0–15, 15–20, 20–30, 30–40, and 40–50 cm) of a long-term experiment at the University of Tokyo, Japan. Three fields have been receiving sewage sludge composted with rice husk (RH), sawdust (SD), or mixed chemical fertilizer NPK (CF), applied at the rate of 240 kg N ha–1 each in split applications in summer and autumn since 1978. Significantly higher amounts of total N and C and soluble organic C were found in the compost than in the CF treatments up to the 40-cm soil depth, indicating improved soil quality in the former. In the CF treatment, soil pH values were significantly lower and electrical conductivity values were significantly higher than those of compost-treated soils of up to 50 cm depth. Soil microbial biomass C and N, CO2 evolution, protease, deaminase, and urease activities were significantly higher in the compost than in the CF treatments due to greater availability of organic substrates that stimulated microbial activity. Gross N mineralization rates determined by 15N dilution technique were eight and five times higher in the SD and RH treatments than in the CF treatment, respectively, probably due to high levels of microbial and enzyme activities. Net N mineralization rates were also significantly higher in the compost treatments and were negative in the CF treatment indicating immobilization. Net nitrification rates were higher in compost treatments and negative in the CF treatment. Nitrous oxide productions from compost treatments were higher than the CF treatment due to the greater availability of mineral N as a result of higher mineralization and nitrification rates and soluble organic C in the former. Most of the measured parameters were highest in the surface soil (0–15 cm) and were significantly higher in the SD treatment than in the RH treatment.  相似文献   
114.
N. Hirota    T. Kaneko    K. Ito    K. Takeda 《Plant Breeding》2006,125(3):231-235
Barley lipoxygenase (LOX)‐1 is believed to affect the stability of flavour and the foam of beer. The purpose of this study was to investigate the genetic variation of the LOX‐1 thermostability, and to analyse the mode of inheritance of this trait. A simple method was established to evaluate the LOX‐1 relative thermostability (LOX‐RTS). With this method, 153 barley cultivars were screened for LOX‐RTS. The frequency of the LOX‐RTS values was distributed in a bimodal manner. Based on these values, the barley lines were categorized into two groups: an H‐type with relatively thermostable LOX‐1 and an L‐type with relatively thermolabile LOX‐1. Using a ‘Steptoe’/‘Morex’ doubled haploid population, a major quantitative trait locus (QTL) associated with LOX‐RTS was identified on chromosome 4H of barley, explaining 82% of the variance. Mapping of a CAPS marker specific for the LoxA locus revealed co‐segregation with this QTL. In this study, the existence of the thermostability types of barley seed LOX‐1 and the locus controlling the thermostability were made clearer.  相似文献   
115.
Aquaculture International - The utilization of sustainable and innovative raw materials to substitute for traditional fishmeal (FM) ingredients is required for the aquaculture sector. Sacha inchi...  相似文献   
116.
In memoriam     
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117.
Immunocytochemical localization of hypocalcin, a hypocalcemic factor in the corpuscles of Stannius (CS), in American eels was examined at the light (ABC method) and electron microscopic (protein A-gold technique) levels with the specific antiserum raised against purified rainbow trout hypocalcin. Only type 1 cells in the CS were immunoreactive in the light microscopic immunocytochemistry. At the electron microscopic level, however, hypocalcin immunoreactivity was observed in secretory granules of both type 1 and type 2 cells. Our findings may indicate that type 1 cells are the main source of hypocalcin, but that type 2 cells also produce it, suggesting that the presence of two cell types reflects different physiological conditions of a single cell type, rather than functionally different cell types. In addition, we summarize our recent data on the localization of other calcium regulatory, or putative calcium regulatory, hormones in fish: parathyroid hormone, calcitonin and calcitonin gene-related peptide.  相似文献   
118.
119.
Urinary and fecal metabolites in male rats treated with a (14)C-labeled fungicide, furametpyr [N-(1,3-dihydro-1,1, 3-trimethylisobenzofuran-4-yl)-5-chloro-1, 3-dimethylpyrazole-4-carboxamide, Limber], were purified by a combination of chromatographic techniques, and chemical structures of 14 metabolites were identified by spectroanalyses (NMR and MS). The major biotransformation reactions of furametpyr in rats were found to be (1) N-demethylation, (2) oxidation of the methyl group at C3 of the pyrazole ring, (3) oxidation of the methyl group at C1 of the 1,3-dihydroisobenzofuran ring, (4) hydroxylation at C3 of the 1,3-dihydroisobenzofuran ring, and (5) hydroxylation at C7 of the 1, 3-dihydroisobenzofuran ring. In vitro metabolism by recombinant human cytochrome P450 revealed that a major biotransformation in humans is N-demethylation, catalyzed by CYP1A1, 1A2, 2C19, and 3A4.  相似文献   
120.
Intergeneric hybridization was performed between Moricandia arvensis and four inbred lines of Brassica rapa following embryo rescue. Three F1 hybrid plants were developed from three cross combinations of M. arvensis × B. rapa, and amphidiploids were synthesized by colchicine treatment. Six BC1 plants were generated from a single cross combination of amphidipolid × B. rapa ‘Ko1-303’ through embryo rescue. One BC2 and three BC3 plants were obtained from successive backcrossing with B. rapa ‘Ko1-303’ employing embryo rescue. Alloplasmic and monosomic addition lines of B. rapa (Allo-MALs, 2n = 21) were obtained from backcrossed progeny of three BC3 plants (2n = 21, 22 and 23) without embryo rescue. An alloplasmic line of B. rapa (2n = 20) degenerated before floliation on 1/2 MS medium due to severe chlorosis. Allo-MALs of B. rapa (2n = 21) showed stable male sterility without any abnormal traits in vegetative growth and female fertility. Molecular analyses revealed that the same chromosome and cytoplasm of M. arvensis had been added to each Allo-MAL of B. rapa. This Allo-MAL of B. rapa may be useful material for producing cytoplasmic male sterile lines of B. rapa.  相似文献   
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