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91.
In order to analyze the structural features of small lignin fragments that are closely associated to polysaccharides, lignin carbohydrate complex (LCC) with low lignin content was extracted with water from the residual wood meal (sugi, Cryptomeria japonica) of milled wood lignin (MWL) isolation. This LCC exhibited almost the same neutral sugar composition as those extracted by other LCC solvents (dimethylformamide, dimethylsulfoxide, and others) but the lignin content was only 5.3%, which was much lower than others. Gel filtration chromatography demonstrated that lignin in this LCC was found together with carbohydrates at the higher molecular weight region, but after the treatment with carbohydrate-degrading enzymes the apparent molecular weight of both lignin and carbo-hydrates decreased significantly. Using a mild alkaline treatment, the apparent molecular weight of lignin also decreased while that of polysaccharide was not affected. These data indicated that lignin in this LCC is present as small fragments attached to high molecular weight polysaccharide at least partly by alkali-unstable linkages. Structural analysis by ozonation method revealed that the lignin in this LCC was lower in erythro/threo ratio of -O-4 structure and relatively richer in the threo type structure carrying C-aryl linkages at -position (-5 and/or -1) than other lignin fractions present in MWL, LCCs extracted by other solvents, and their extraction residues. It was suggested that the chemical structure of lignin closely associated to carbohydrates was different from that of the main part of lignin.This paper was presented in part at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, Japan, April 2002, at the 47th Lignin Symposium, Gifu, Japan, October 2002, and at the 12th International Symposium on Wood and Pulping Chemistry, Madison, USA, June 2003  相似文献   
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93.
ABSTRACT: The surface-migratory myctophid fish, Myctophum asperum , of the western North Pacific was found to have daily growth increments of its sagittal otolith, which also exhibited lunar periodicity in the deposition of increments. Daily deposition of the otolith increments was verified because the width of the marginal increment increased during the night and early morning between 20.00 h and 08.00 h and its growth stopped during the day. An autocorrelation analysis of the increment widths, which were measured consecutively in 11 specimens covering 33 synodic months, also showed a lunar periodicity in increment deposition. The mean increment widths during five days around the time of a full moon were significantly narrower than those around a new moon in 18 of the 33 full moon cases ( P < 0.01: Student's t -test) and, on average, tended to be narrow in 29 cases. The cause of this tendency is thought to be slower growth caused by staying in deeper and colder habitat due to the suppression of diel vertical migration and/or lower food availability resulting from the possible dispersion of zooplankton during the full moon period.  相似文献   
94.
The leptin receptor (LEPR) gene is considered a candidate gene for fatness traits. It is located on SSC 6 in a region in which quantitative trait loci (QTLs) for backfat thickness (BF), fat area ratios, and serum leptin concentration (LEPC) have previously been detected in a Duroc purebred population. The objectives of the present study were to identify porcine LEPR polymorphisms and examine the effects of LEPR polymorphisms on fatness traits in this same population. The Duroc pigs (226 to 953 pigs) were evaluated for BF, fat area ratios using image analysis, and LEPC. A total of seven single nucleotide polymorphisms (SNPs) in the full‐length LEPR coding region were identified in pigs from the base population. Four non‐synonymous SNPs of the LEPR gene and 15 microsatellite markers on SSC 6 were then genotyped in all pigs. During candidate gene analysis, we detected significant effects of the non‐synonymous SNP c.2002C>T in exon 14 on all traits. In fine mapping analysis, significant QTLs for BF, fat area ratios, and LEPC were detected near the LEPR gene in the same region. These results indicated that the c.2002C>T SNP of LEPR has a strong effect on BF, fat area ratios and LEPC.  相似文献   
95.
Seventeen cases of lymphoid neoplasms in swine were investigated and divided into eight histological types. Cases 1-3 were precursor B lymphoblastic leukemias, which occurred in three piglets from the same dam. Cases 4 and 5 were diagnosed, respectively, as a precursor B lymphoblastic lymphoma and a thymic B cell lymphoma, because there were cytological differences between the lymphomas. These five cases of immature B cell malignancies expressed CD79a and terminal deoxynucleotidyl transferase (TdT). Mature B cell lymphomas were divisible into follicular (case 6), diffuse centroblastic (case 7) and intestinal large B cell (cases 8-11) lymphomas. Unlike in case 7, the neoplastic cells in cases 8-11 showed cytological features intermediate between centroblasts and immunoblasts. The mature lymphomas were characterized by positive immunolabeling for CD79a and cytoplasmic immunoglobulins. A case of thymic γδ T cell lymphoma (case 12) were positive for CD3, CD5, WC1 and TdT. Instead of TdT, perforin was expressed in γδ T cell lymphomas (cases 13-17), whose histological characteristics were epitheliotropism, homing into T cell zones of lymphatic tissues, and cytological atypia and pleomorphism. In the present study, lymphoid neoplasms could be classified into discrete histological types, some of which were considered to be specific for swine.  相似文献   
96.
Aquaculture of Japanese eel Anguilla japonica relies upon the natural recruitment of their glass eels (juveniles); however, predation that could influence glass eel recruitment remains unknown. In the present study, we aimed to elucidate the proportion of predation on A. japonica glass eels through stomach content analysis of predatory fishes collected in the estuary region of the Tone River system and its vicinity in Japan. Species of the predated glass eels were identified by DNA barcoding. A total of 270 predatory fishes of 15 taxa was collected over 2 years. The overall proportion of predation on glass eels, genetically identified as Japanese eel, was 0.7%, but this rose to 2.0% when data were limited to fishes caught during the peak months of glass eel recruitment. A glass eel was found in the stomach contents of a channel catfish Ictalurus punctatus, an invasive species in this river system, and a blackfin sea bass Lateolabrax latus. These fishes are therefore considered potential predators of A. japonica glass eels. However, as the proportion of predation was low, and the glass eels represented only small proportions of predator stomach contents, further investigation is needed for a better understanding of predation on A. japonica glass eels, and its effects on the early life stages of this endangered species.  相似文献   
97.
The present study describes the influence of temperature levels and planting time on the sprouting of rhizome-buds and the biomass production of torpedograss ( Panicum repens L.) in the Okinawa prefecture, Japan. Torpedograss planted in each month (1994–95) was grown for 210 days. Sprouting of the rhizome-bud of torpedograss was 92–96% at the temperature range of 20–35°C in an incubator, and the sprouting was not observed at the extreme low and high temperature of ≤5 and ≥45°C, respectively. The plant showed 40–72% emergence when grown in pots throughout the year in the ambient temperature range of 17–29°C. The percentage emergence was comparatively higher in March to September, and shoots elongated rapidly in the period from April to October when the temperature range of 22–29°C prevailed. Torpedograss-rhizome sown in the period from January to June obtained significantly higher biomass because higher temperatures prevailed in the following growth period from May to October, as compared with the torpedograss-rhizome sown in the period of July to December. The plant required higher temperatures for proper growth and development during the period of moderate (70–110 days after planting (DAP)) and fast growth phases (110 DAP to the last harvest).  相似文献   
98.
Potassium bromide overdose (bromism) in the management of canine epilepsy has been known. However, a protocol to reduce bromide concentrations rapidly has not been previously established. The effects of three infusion fluids with different chloride contents on the steady‐state serum concentrations of bromide in beagles were determined. After stabilization of the serum bromide concentrations, seven dogs were infused with saline (Na+ 154 mmol/L; Cl? 154 mmol/L), lactated Ringer's (Na+ 131 mmol/L; Cl? 110 mmol/L), or maintenance solutions (Na+ 35 mmol/L; Cl? 35 mmol/L) at a rate of 2 or 10 ml kg?1 hr?1 for 5 hr. Serum and urine were collected hourly, and the bromide concentrations were measured. When saline and lactated Ringer's solutions were infused at a rate of 10 ml kg?1 hr?1 for 5 hr, serum bromide concentrations were decreased by 14.24% and urine bromide concentrations by 17.63%, respectively. Of all compositions of infusion fluids, only sodium and chloride contents were associated with the decreased serum concentrations and the increased renal clearance of bromide. In summary, saline and lactated Ringer's solutions reduced serum bromide concentrations in a sodium chloride‐dependent manner in dogs were found when infused at 10 ml kg?1 hr?1 for 5 hr.  相似文献   
99.
100.
To clarify the role of progesterone in the development of immune responses during pregnancy against Neospora caninum infection, C57BL/6 mice were given a progesterone pellet, and measured on Interferon-gamma and interleukin-4 production following the infection. IFN-gamma production in the prescribed group was significantly lower than that in the intact group on day 40 post administration. IL-4 producing cell population in the prescribed group was larger than that in the intact group. These results suggest that progesterone may alter the balance of cytokine production, and that the bias toward type 2 immune response may remain for a certain period after the infection.  相似文献   
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