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71.
K Takahashi S Naga T Yagihashi T Ikehata Y Nakano K Senna T Maruyama J Murofushi 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(5):487-491
Cross-protection between Haemophilus parasuis serovars 2 and 5 was examined in pigs using a bacterin based vaccine, and subsequently the safety and efficacy of a bivalent vaccine were evaluated. Upon intratracheal challenge of a serovar 2 or 5 strain, pigs immunized with a monovalent vaccine were protected against challenge with a homologous serovar strain, but not with a heterologous serovar strain. Immunization with a bivalent vaccine containing both serovars 2 and 5 bacterins conferred protection in pigs against lethal challenge with each of the serovar strains. A total of 86 pigs from two SPF herds were injected with the bivalent vaccine intramuscularly twice at a four-week interval. No adverse reactions following the vaccination were observed. On day 7 after the second vaccination, vaccinated and non-vaccinated control pigs from herd A were transferred to herd B, where Glasser's disease had broken out. Pigs in the control group developed clinical signs of the disease, and 6 of 8 (75%) pigs died until slaughter, in contrast with only 4 of 46 (9%) pigs in the vaccinated group. In herd C, where there was no outbreak of Glasser's disease, complement fixation antibody titer was raised only in the vaccinated group. A challenge experiment on days 20 and 79 after the second vaccination showed that only the vaccinated pigs were protected. From these findings, the safety and efficacy of the bivalent vaccine were confirmed under laboratory and field conditions. 相似文献
72.
Abstract – The residency and movement of stream-dwelling adult (2+ and older) Japanese charr, Salvelinus leucomaenis , were studied by mark and recapture experiments in the Jadani Stream, a headwater tributary of the Tedori River, central Japan, from 1986 to 1989. Of the marked fish, 31.3–58.3% were recaptured in the same pools where they had been caught during the study periods of summer (June–August), autumn (August–November) and winter–spring (November to the next June) and no seasonal movement was observed. The mean distances that the fish moved during the study periods ranged from 139.0 to 502.3 m and many movements longer than 1000 m were observed. Between the resident and the moved fish, there was little difference in body length, growth rate or sex. For the fish that had been resident in the same pools and riffles at previous recaptures, most fish were recaptures in the same locations at the next recapture. Conversely, for the fish that moved previously, most fish were recaptured in different locations from previous sites at the next recapture. These results suggest that Japanese charr exhibit relatively high residency throughout the year, but many fish moved longer distance. The results also suggest the presence of static and mobile components in the charr population. 相似文献
73.
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75.
Takashi Yamasaki Ayumi Enomoto Atsushi Kato Tadashi Ishii Kazumasa Shimizu 《Journal of Wood Science》2011,57(1):76-84
Arabinoglucuronoxylans (AGXs) isolated from the holocellulose of sugi (Cryptomeria japonica) and hinoki (Chamaecyparis obtusa) contained one 4-O-methyl-d-glucopyranosyluronic acid (4-O-Me-d-GlcAp) residue per 6.2 d-xylopyranose (d-Xylp) residues and one 4-O-Me-d-GlcAp residue per 3.8 d-Xylp residues. These AGXs were subjected to partial acid hydrolysis. Analyses by size exclusion chromatography and electrospray-ionization
mass spectroscopy of the neutral sugar fractions in the hydrolysates showed the presence of xylooligosaccharides having a
degree of polymerization of 2-8 in addition to d-Xyl, suggesting that the AGXs from sugi and hinoki contained unsubstituted chains consisting of at least eight d-Xyl residues. The acidic sugars in the hydrolysates were separated into two series of aldouronic acids composed of 4-O-Me-d-GlcAp and d-Xylp by ion-exchange chromatography. The first series included aldouronic acids from aldobiouronic acid (4-O-Me-d-GlcAp-Xyl) to aldopentaouronic acids (4-O-Me-d-GlcAp-Xyl4). The second series were aldouronic acids composed of two 4-O-Me-d-GlcAp residues and 2-4 d-Xyl residues. In these acidic sugars, the uronic acid side chains were located on two contiguous d-Xyl residues. These facts indicated that AGXs from sugi and hinoki had a structural unit containing two 4-O-Me-d-GlcAp residues on two contiguous d-Xyl residues as well as AGXs from spruce and larch. 相似文献
76.
Maruyama N Mohamed Salleh MR Takahashi K Yagasaki K Goto H Hontani N Nakagawa S Utsumi S 《Journal of agricultural and food chemistry》2002,50(15):4323-4326
We purified four single molecular species of beta-conglycinin heterotrimers consisting of the alpha and beta subunits or the alpha' and beta subunits from mutant soybean cultivars lacking the alpha or alpha' subunit, respectively, and examined their structural features and physicochemical functions. The extent of the hydrophobicities of the heterotrimers was related to the number of the alpha or alpha' subunit. The thermal stabilities of the heterotrimers were mainly conferred by the subunit which had lower thermal stability. Solubilities at low ionic strength (mu = 0.08) of the heterotrimers containing the alpha or alpha' subunit were very similar to those of the alpha and alpha' homotrimers, respectively. Emulsifying abilities and heat-induced associations of the heterotrimers containing one beta subunit were similar to those of the alpha or alpha' homotrimer, whereas those of the heterotrimers containing two beta subunits were similar to those of the beta homotrimer. 相似文献
77.
Hitoshi Fujiie Atsushi Maruyama Masako Fujiie Michiko Takagaki Douglas J. Merrey Masao Kikuchi 《Irrigation and Drainage Systems》2011,25(1):39-60
It is well-known that major irrigation projects have a strong scale economy, handicapping irrigation development in sub-Saharan
Africa (SSA) because of the difficulty in formulating large-scale projects. Using project-level investment cost and performance
data of major and minor irrigation projects, this paper examines the causes of the economy of scale phenomenon. We find that
strong scale economy exists not only for major but also for minor projects, i.e., small- and micro-scale, projects. This is
largely because of the existence of indivisible overhead costs such as high-opportunity-cost human resources for planning,
designing and engineering management and supervision. We also find that large differences between major and minor projects
in the absolute level of overhead as well as construction costs creates a strong scale diseconomy and results in better performance
of minor projects. The advantage of minor projects holds even when their higher risk associated with the water source is taken
into consideration. We argue that there is an urgent need to promote irrigation development in SSA through developing minor
projects, and to reduce the heavy burden of overhead costs by developing the capacity of human resources at the national,
local and farmer levels in the fields of irrigation engineering, irrigation agronomy, institutional development, and micro
water management technologies. 相似文献
78.
Rensing SA Lang D Zimmer AD Terry A Salamov A Shapiro H Nishiyama T Perroud PF Lindquist EA Kamisugi Y Tanahashi T Sakakibara K Fujita T Oishi K Shin-I T Kuroki Y Toyoda A Suzuki Y Hashimoto S Yamaguchi K Sugano S Kohara Y Fujiyama A Anterola A Aoki S Ashton N Barbazuk WB Barker E Bennetzen JL Blankenship R Cho SH Dutcher SK Estelle M Fawcett JA Gundlach H Hanada K Heyl A Hicks KA Hughes J Lohr M Mayer K Melkozernov A Murata T Nelson DR Pils B Prigge M Reiss B Renner T Rombauts S Rushton PJ 《Science (New York, N.Y.)》2008,319(5859):64-69
We report the draft genome sequence of the model moss Physcomitrella patens and compare its features with those of flowering plants, from which it is separated by more than 400 million years, and unicellular aquatic algae. This comparison reveals genomic changes concomitant with the evolutionary movement to land, including a general increase in gene family complexity; loss of genes associated with aquatic environments (e.g., flagellar arms); acquisition of genes for tolerating terrestrial stresses (e.g., variation in temperature and water availability); and the development of the auxin and abscisic acid signaling pathways for coordinating multicellular growth and dehydration response. The Physcomitrella genome provides a resource for phylogenetic inferences about gene function and for experimental analysis of plant processes through this plant's unique facility for reverse genetics. 相似文献
79.
Data on enzyme polymorphism and blood group polymorphism were examined with special reference to molecular evolution, by using a statistic that depends on neither population structure nor other ecological factors. The data of the former are consistent with the hypothesis of neutral mutant and random genetic drift, whereas the latter are in accord with the hypothesis of balanced selection. 相似文献
80.
Watanabe T Tomizawa S Mitsuya K Totoki Y Yamamoto Y Kuramochi-Miyagawa S Iida N Hoki Y Murphy PJ Toyoda A Gotoh K Hiura H Arima T Fujiyama A Sado T Shibata T Nakano T Lin H Ichiyanagi K Soloway PD Sasaki H 《Science (New York, N.Y.)》2011,332(6031):848-852
Genomic imprinting causes parental origin-specific monoallelic gene expression through differential DNA methylation established in the parental germ line. However, the mechanisms underlying how specific sequences are selectively methylated are not fully understood. We have found that the components of the PIWI-interacting RNA (piRNA) pathway are required for de novo methylation of the differentially methylated region (DMR) of the imprinted mouse Rasgrf1 locus, but not other paternally imprinted loci. A retrotransposon sequence within a noncoding RNA spanning the DMR was targeted by piRNAs generated from a different locus. A direct repeat in the DMR, which is required for the methylation and imprinting of Rasgrf1, served as a promoter for this RNA. We propose a model in which piRNAs and a target RNA direct the sequence-specific methylation of Rasgrf1. 相似文献