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1.
RNA-silencing suppressors of geminiviruses   总被引:2,自引:0,他引:2  
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2.
In a previous study, it was found that there are sex differences in goats with respect to the levels of cortisol secretion induced by transportation stress. We also found that treatment of castrated male goats with dihydrotestosterone (DHT) suppressed the increase in plasma cortisol concentration following transportation, but did not suppress the secretion of adrenocorticotropic hormone (ACTH). This suggests that androgen might block ACTH ‐ induced cortisol secretion. In order to examine this hypothesis, the effects of androgen on ACTH‐induced cortisol secretion in goats were investigated. First, castrated male goats were treated with testosterone (T), DHT or cholesterol (cho) for 21–25 days. Cho was used as a control for T and DHT treatment. Then, plasma cortisol concentrations were compared among the hormonal treatments after ACTH injection. Subsequently, the distribution of androgen receptors in the caprine adrenal gland was investigated. There were no differences in the basal cortisol concentrations among the hormonal treatments. However, plasma cortisol concentrations after ACTH injection were significantly lower in T ‐ and DHT ‐ treated goats than in cho ‐ treated goats. Androgen receptors were present in 60% of the cells in the zonae fasciculata and reticularis of the adrenal cortex, the regions that secrete glucocorticoids. These results suggest that androgen may act directly on the adrenal cortex to suppress cortisol secretion induced by ACTH.  相似文献   
3.

The goal of this study was to determine the effects of the fermented juice of epiphytic lactic acid bacteria (FJLB) on the quality of total mixed ration (TMR) silage containing agricultural by-products, its digestibility, rumen fermentation, and nitrogen balance in ewes. TMR was prepared from rice straw, corn stover silage, brewer grain, tofu waste, steam-flaked corn, and a mineral mixture. The treatments consisted of silage additives added to TMR: CON (no silage additive), FJLB, COM (commercial additive), and MIX (FJLB + COM). Four cannulated ewes were assigned to the 4 × 4 Latin square design. The MIX treatment produced a lower (P < 0.01) pH than did the CON and FJLB treatments and a higher (P < 0.01) lactic acid concentration than did the other treatments. The fiber content in the COM treatment was lower (P < 0.05) than that in the other treatments. The FJLB treatment had similar fermentation quality and chemical composition to those of the CON and COM treatments in all parameters observed. Although the silage quality index (Fleig point) was higher in the MIX and COM treatments than in the CON treatment, all silages had good quality. No silage additives affected intake, digestibility, rumen fermentation, or nitrogen balance. In conclusion, the TMR silage prepared from agricultural by-products mixed with wet-type food by-products with or without FJLB added resulted in well-preserved fermentation, and this product might be used as a ruminant feed.

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4.
To assess whether the antigenic properties of H5 hemagglutinin (HA) change over time due to antigenic drift, we produced a panel of monoclonal antibodies (mAbs) against the HA of the index H5N1 human influenza A virus, A/Hong Kong/156/97. By immunizing mice with a plasmid expressing this HA and boosting the initial immunization with cell lysates transfected with the plasmid, a total of six hybridomas producing HA-specific mAbs were established: four to the HA1 subunit with hemadsorption-inhibiting activity and two to the HA2 subunit. None of the mAbs to HA1 could bind to the HA of a recent human isolate, A/Hong Kong/213/2003, indicating that there are substantial antigenic differences between the H5N1 human influenza virus isolated in 1997 and that isolated in 2003.  相似文献   
5.
We examined the antimicrobial susceptibility of 848 Escherichia coli isolates from 237 feces samples of wild sika deer (Cervus nippon) captured between 2016 and 2019 in 39 of the 47 prefectures of Japan. Five of the 237 wild sika deer (2.1%) carried E. coli with resistance to at least one antimicrobial, and all the resistant isolates showed resistance to tetracycline. The resistant isolates contained antimicrobial resistance genes that were similar to those in E. coli derived from humans and farm animals. Although wild sika deer are not currently likely to be a source for the transmission of antimicrobial resistance in Japan, they can potentially mediate antimicrobial resistance spread by coming into contact with humans, animals, and their surroundings.  相似文献   
6.
Severe adverse reactions in cats after vaccination were examined from 316 cases reported to the Ministry of Agriculture, Forestry and Fisheries (MAFF) in Japan during 15-year period from April 2004 to March 2019. We found that 130 (41%) showed anaphylaxis, and 99 (76%) of the 130 cases of anaphylaxis resulted in death. Veterinarians should be well prepared to deal with vaccine-associated anaphylaxis in cats. Bovine serum albumin (BSA) as indicator of purification was detected at high levels in commercially available feline vaccines. BSA might derive from fetal calf serum in culture media. This study provides useful information about anaphylaxis including critical details of the potential clinical signs associated with adverse events to feline vaccination.  相似文献   
7.
Patchouli (Pogostemon cablin (Blanco) Benth), an aromatic crop which yields an essential oil, is widely cultivated in South-east Asia. Patchouli mild mosaic virus (PaMMV) infects patchouli plants and causes decrease in leaf biomass and essential oil yield. Transgenic patchouli plants with PaMMV coat protein precursor (CP-P) gene have been produced by Agrobacterium-mediated transformation. PaMMV CP-P gene integration into the patchouli genome was confirmed by the PCR method and by Southern blot analysis. The transformants were estimated to contain one to three copy genes using Southern blot analysis. The transformant with three copy genes was tested for the resistance to PaMMV by artificially inoculating plants grown in an environmentally controlled cabinet, and this transformant was found to be highly resistant to PaMMV. The transgenic patchouli plant with PaMMV CP-P gene should provide valuable material for protecting against PaMMV.  相似文献   
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9.
Previous trials have revealed variable responses of sago palm ( Metroxylon sagu Rottb.) to fertilizer application, particularly nitrogen (N). In the present study, we quantified the fertilizer use efficiency (FUE) of sago palm for the first time using 15N-labeled fertilizer in pot and field experiments. The pot experiment was conducted in Japan using a 2:1 mixture of sand to Philippine soil. The field experiment was conducted in Leyte in the Philippines. Both experiments consisted of three replicates in each of three treatments: control, 15N urea at 50 kg N ha−1 and 15N urea at 100 kg N ha−1. The N uptake of sago palm increased significantly, but inconsistently with increasing N application. The few instances of a significant increase in N uptake did not translate into significant improvements in growth parameters, except for the number of leaflets in the pot experiment. The FUE values for sago seedlings (< 6 months) in the pot experiment treated with 50 and 100 kg N ha−1 were 10.5 and 13.2%, respectively, whereas for the 2-year-old sago palms in the field, the corresponding FUE values were 14.8 and 12.0%. The FUE values were similar at the two levels of N application in both experiments. Sago growth parameters appeared to be insensitive to N application, suggesting that the form of N and the timing of N fertilization are important factors for sago palms. Therefore, the use of N fertilizer in sago production can only be justified after determining and fully understanding the response of sago palm to N application.  相似文献   
10.
To test the effects of probiotic bacteria against crowding stress, juvenile Nile tilapia Oreochromis niloticus were fed commercial feed supplemented with 1 × 1010 cfu/g pellets of Lactobacillus rhamnosus for 3 weeks. The fish were confined and subjected to crowding for 7 and 14 days after which their physiological condition was investigated. The administration of probiotic prophylaxis improved growth performance even in the stressed fish. After 7 days of stress exposure, fish receiving probiotic-supplemented feed showed proactive behavior and coping responses to the stressor, as evidenced by elevated plasma glucose levels and osmolality, stabilized plasma electrolytes, and a higher RNA:DNA ratio. Fish stressed for 7 days and fed normal commercial diet showed impairment of plasma electrolytes; after 14 days, the plasma osmolality, electrolytes, glucose, and RNA:DNA ratio decreased, indicating physiological maladaptation to the stressor. The growth rate was also found to be reduced, suggesting that energy demand exceeded the energy available from metabolism and dietary uptake. This latter effect was not observed in fish fed the probiotic-supplemented diet. The results suggest that probiotic bacteria prophylaxis may increase energy availability for metabolic support of the crowding stress response and improve the stress coping capacity of fish.  相似文献   
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