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61.
This study compared the immunosuppressive effects of dexamethasone (DEX), flunixin meglumine (FLU) and meloxicam (MEL) on the peripheral blood mononuclear cells (PBMCs) of seven healthy Holstein calves in vitro. DEX significantly inhibited lymphocyte proliferation and expression of interferon (IFN)-γ, interleukin (IL)-2 and IL-4 messenger RNA (mRNA) in comparison with FLU and MEL. FLU and MEL dose-dependently inhibited lymphocyte proliferation, but did not significantly reduce mRNA expression. Our in vitro study indicates that steroidal anti-inflammatory drugs (SAIDs) as well as nonsteroidal anti-inflammatory drugs (NSAIDs) have immunosuppressive effects on calf PBMCs. These findings are important for assessing the indications and complications of NSAIDs in calves.  相似文献   
62.
A 5-month-old female Citron-crested Cockatoo (Cacatua sulphurea citrinocristata) that was born and hand-reared in Japan died with suspected proventricular dilatation disease (PDD). Macroscopic and microscopic examinations of the bird revealed characteristic features of PDD, i.e., distention of the proventriculus and infiltration of lymphocytes and plasma cells in ganglia of various organs and in central and peripheral nerves. A linkage of this PDD case to infection with avian bornavirus (ABV) was documented by RT-PCR amplification of the virus genomes from the affected bird. Phylogenetic analysis revealed that the ABV identified in this study clustered into the genotype 2, which is one of the dominant ABV genotypes worldwide. To the best of our knowledge, this is the first report of a natural case of PDD associated with ABV infection in Japan.  相似文献   
63.
Abstract

Nodule formation in legume crops is a multistep process which involves the interactive gene expression of bacteria and host plants. Attempts to widen the genetic variation of symbiotic bacteria and host plants have led to the isolation of several mutants with a diverse capability of nodulation. The most striking variants in hosts are the supernodulating mutants isolated in pea (Pisum sativum L.) (Jacobsen and Feenstra 1984; Duc and Messager 1989), common bean (Phaseolus vulgaris L.) (Park and Buttery 1988), and soybean (Glycine max (L.) Men.) (Carroll et al. 1985a,b; Gremaud and Harper 1989; Akao and Kouchi 1992), all of which are capable of producing several-fold more nodules than their parental lines in the presence of nitrate. These mutants may be useful materials for analyzing the mechanism controlling nodule formation, and are considered to have a high agronomic potential under certain growing conditions.  相似文献   
64.
An experiment was conducted to determine if salinity stress alters the response and tolerance of soybean to defoliation. Four soybean [Glycine max(L.) Merr.] cultivars (‘Tachiutaka,’ ‘Tousan 69,’ ‘Dare’ and ‘Enrei’) in a growth chamber were exposed to two salinity treatments (0 and 40 mM NaCl) and two defoliation treatments (with and without defoliation). The interactive effects of salinity stress and defoliation on growth rate, leaf expansion, photosynthetic gas exchange, and sodium (Na+) accumulation were determined. The decrease in growth rate resulting from defoliation was more pronounced in plants grown under salinity stress than in those grown without the stress. Without salinity stress, defoliated plants of all four cultivars had leaf-expansion similar rates to those of the undefoliated ones, but the photosynthetic rates of their remaining leaves were higher than those of undefoliated plants. However, with salinity stress, defoliated ‘Tachiutaka’ and ‘Tousa 69’ had lower leaf expansion and photosynthetic rates than undefoliated plants. For cultivars ‘Dare’ and ‘Enrei,’ the defoliated plants had leaf-expansion rates similar to undefoliated ones, but the photosynthetic rate of the remaining leaves did not increase. Except for cultivar ‘Dare,’ defoliated plants grown under salinity stress had higher Na+ accumulation in leaves than undefoliated ones, and this result may be related to slow leaf expansion and photosynthesis. Salinity stress negatively affects soybean response and tolerance of defoliation, and the effects varied according to the salt tolerance of the cultivar.  相似文献   
65.
The function of an Arabidopsis thaliana gene, At5g54160 annotated as a caffeic acid O-methyltransferase CAOMT gene was characterized. The recombinant enzyme of this gene (AtOMT1) catalyzed the O-methylation of phenylpropanoid and flavonoid substrates. The specificity constants (k cat/K m) for 5-hydroxyconiferaldehyde (5-HCAld) and quercetin were both 0.11 μM−1·min−1. On the other hand, lignins of At5g54160-knockout Arabidopsis mutants lacked syringyl units. In addition, we showed that the gene silencing also resulted in significant accumulation of caffeyl alcohol (CaAlc). These results strongly suggested that At5g54160 gene is involved in syringyl lignin synthesis for the methylation of both 5-hydroxyconiferaldehyde and 3,4-dihydroxyphenyl compound(s). Part of this work was presented at the Annual Meeting of Japan Society for Bioscience, Biotechnology, and Agrochemistry, March 24–27, 2007  相似文献   
66.
Thymelaeaceae plants produce dextrorotatory dibenzylbutyrolactone lignans, which are opposite enantiomers to the lignans isolated from other plants (e.g.,Forsythia spp.). In our previous paper, (–)-pinoresinol (74% enantiomer excess), (+)-matairesinol (optically pure), and (+)-wikstromol (optically pure) were isolated fromWikstroemia sikokiana (Thymelaeaceae). In the present investigation, a survey of lignans and the determination of their enantiomeric compositions were continued. Four lignans, (–)-lariciresinol, (–)-secoisolariciresinol, (+)-kusunokinin, and (+)-methyltrachelogenin, were isolated from MeOH extracts ofW. sikokiana stem. To our knowledge, we have isolated (+)-methyltrachelogenin from plants for the first time. Chiral high-performance liquid chromatographic analysis showed that (+)-kusunokinin and (+)-methyltrachelogenin were optically pure, whereas (–)-lariciresinol and (–)-secoisolariciresinol were not (39% and 45% enantiomer excess, respectively). Feeding experiments with deuterium-labeled substrates demonstrated conversion of coniferyl alcohol to the lignans and interconversion of lignans. These reaction sequences are similar to the sequence catalyzed byForsythia enzymes. However, predominant enantiomers of the lignans, except for secoisolariciresinol isolated fromW. sikokiana, have absolute configurations opposite to those of the corresponding lignans isolated fromForsythia spp. Based on the results of the isolation and the feeding experiments, several differences betweenW. sikokiana andForsythia spp. are pointed out regarding stereochemical mechanisms for lignan biosynthesis.Parts of this report were presented at the 46th annual meeting of the Japan Wood Research Society, Kumamoto, April 1996; and the 47th annual meeting of the Japan Wood Research Society, Kochi, April 1997  相似文献   
67.
68.
The effects of a higher concentrate feed during the raising period on the growth and carcass of Japanese Black cattle being fattened at a younger age were investigated using three pairs of artificially bred identical twins and three pairs of full‐sibs. The animals were fed the concentrate at 2.4%/day (2.4% group) and 1.2%/day (1.2% group) comparative bodyweight (BW) during the raising period. The BW and subcutaneous fat thickness were measured every month using ultrasonic equipment. The animals were slaughtered at the age of 24 months. The BW of the 2.4% group from the age of 6–10 months appeared to be higher than that of the 1.2% group (P < 0.1). The subcutaneous fat of the 2.4% group from the age of 7–11 months was thicker than that of the 1.2% group (P < 0.1). After those ages, the BW and subcutaneous fat of the two groups did not differ and there was no difference in the carcass characteristics between the two groups. Using a higher concentrate feed during the raising period for younger fattening of Japanese Black cattle influenced growth from the late half of the raising period to the early part of the fattening period.  相似文献   
69.
Cancer stem‐like cells (CSCs)/cancer‐initiating cells (CICs) are a small subpopulation of cancer cells that are responsible for the initiation, recurrence and metastasis of cancer. We previously demonstrated that, using the Hoechst 33342 dye‐based side population technique, CSCs/CICs in canine lung adenocarcinoma cell line exist. In this study, as CSCs/CICs are known to form spheres in anchorage‐independent environment in vitro, we evaluated the stemness of spheroid cells derived from canine lung adenocarcinoma and osteosarcoma cells by expression of stemness markers, and investigated radioresistance. Spheroid cells showed greater expression of stemness markers Oct‐4 and CD133 gene than those of adherent‐cultured cells. In nude mouse xenograft models, spheroid cells showed higher tumourigenic ability than adherent‐cultured cells. In addition, spheroid cells showed significantly resistant against radioactivity as compared with adherent‐cultured cells. These results suggest that spheroid cells could possess stemness and provide a CSCs/CICs research tool to investigate CSCs/CICs of canine tumour cells.  相似文献   
70.
To elucidate the fate of photosynthates from different current shoots and their influence on fruit growth and bud differentiation in neighboring spur complex during the period of rapid fruit growth in two late-maturing Japanese pear cultivars: ‘Atago’ and ‘Shinkou’ with contrasting fruit size, 13C labeling of single shoot was done to investigate of C-relations in fruit branches of eight shoot-combinations. The results showed that all of the current shoots investigated (bourse shoots of nonfruiting spur, bourse shoots of fruiting spur, extension shoot, nonfruiting spur, vegetative shoot, and water sprout) could export photosynthates to the neighboring fruit and buds. Water sprouts together with vegetative shoots, bourse shoots, and extension shoots are important source for fruit growth after shoot growth termination during the period of rapid fruit growth in production of late-maturing pears. The carbon transfer rate from the neighboring to the fruit bearing spur is depent (i) on the types of shoot which acts as C source, (ii) on the position of the fruiting spur and (iii) on the source-sink distance. Furthermore, the cultivar difference in carbon partitioning from different current shoot-combinations confirmed that the movement of photosynthates into the fruit was determined by sink strength of the fruit, and ‘Atago’ exhibited a greater relative sink strength of fruit than ‘Shinkou’. In addition, vegetative shoots are very important C sources for fruit growth in ‘Atago’ and the growth pattern of bourse shoot seriously affects C allocated to fruit in ‘Shinkou’.  相似文献   
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