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991.
Viral movement in the leaf tissues of a resistant host, Cucumis figarei, inoculated with the pepo strain of Cucumber mosaic virus (CMV) and incubated at 24°C or 36°C was investigated by fluorescence in situ hybridization (FISH), leaf-press blotting, tissue printing and immunogold-silver staining techniques. Observation by FISH
revealed that at 24°C most infection sites with CMV at 0.01 mg/ml or 0.1 mg/ml were limited to a single cell during the incubation
period, that the number of infection sites increased from 24hpi (hours post inoculation) to 80 hpi in the leaves inoculated
with CMV at 0.5 mg/ml, and that the size as well as the number of infection sites rapidly increased with time in the leaves
inoculated with CMV at 2.0 mg/ml. These results suggested that one factor for the resistance of C. figarei at 24°C might be an inhibition of viral movement in and out of the infection sites. Leaf-press blotting and tissue blotting
indicated that CMV remained in the infection sites at 24°C, whereas it spread from the inoculated leaves to other parts of
the plants through vascular systems at 36°C. Immunogold-silver staining demonstrated that at 24°C CMV infected bundle sheath
(BS) cells in minor veins, whereas at 36°C it invaded not only BS cells, but also phloem parenchyma (PP)/ companion cell (CC)
or PP/intermediary cell (IC) complexes in minor veins in the regions with chlorotic symptoms. These results indicated that
at 24°C CMV had difficulty in passing through the interface between BS and PP/CC or PP/ IC complexes and that viral entry
from mesophyll to the phloem pathway was inhibited in the inoculated leaves.
Received 26 August 1999/ Accepted in revised form 14 December 1999 相似文献
992.
993.
To evaluate the importance of acetic acid and 3-hydroxybutyric acid (3-HB) in cerebrospinal fluid (CSF) of cattle, CSF samples were taken from a population of 60 cattle including healthy and sick animals with central nervous disorders. Mean acetic acid and 3-HB levels in blood plasma were 0.30 (SD 0.24) and 0.30 (SD 0.28) mM, and those in CSF were 0.14 (SD 0.06) and 0.08 (SD 0.07) mM, respectively. Significant differences were observed between plasma and CSF samples for both acetic acid and 3-HB levels. Acetic acid levels in CSF showed less relationship with those in blood plasma, whereas plasma 3-HB levels accompanied proportional changes with its CSF levels, which were about 30% of plasma 3-HB. It was revealed that both acetic acid and 3-HB levels in plasma and CSF have less relationship to glucose levels in plasma and CSF; therefore, the decrease of glucose levels in plasma or CSF is not necessarily accompanied by hyperketonemia. 相似文献
994.
995.
Takashi Hirooka Yukio Miyagi Fujio Araki Hitoshi Kunoh Hiroshi Ishizaki 《Pest management science》1982,13(4):379-386
The effect of isoprothiolanea (di-isopropyl 1,3-dithiolan-2-ylidenemalonate), a systemic fungicide used for rice blast control, on the infection process of Pyriculuria oryzae was studied by micromanipulation in a scanning electron microscope. Whether or not infection pegs emerged from the appressoria was examined by inverting each appressorium contact surface. Infection pegs were observed on more than 80% of the appressoria, 48 h after inoculation, on both untreated rice leaves and cellophane film. Isoprothiolane, approximately 10 μg ml?1 in the ambient water of inoculated conidia, reduced the emergence of infection pegs on rice leaves and cellophane film by 96 and 100%, respectively. 相似文献
996.
Samad RA Nomura N Tsuda Y Manzoor R Kajihara M Tomabechi D Sasaki T Kokumai N Ohgitani T Okamatsu M Takada A Sakoda Y Kida H 《The Japanese journal of veterinary research》2011,59(1):23-29
Inactivated influenza virus vaccine prepared from a non-pathogenic influenza virus strain A/duck/Hokkaido/Vac-1/2004 (H5N1) from the virus library conferred protective immunity to chickens against the challenge of antigenically drifted highly pathogenic avian influenza virus (HPAIV), A/whooper swan/Hokkaido/1/2008 (H5N1). The efficacy of the vaccine was comparable to that prepared from genetically modified HPAIV strain deltaRRRRK rg-A/ whooper swan/Mongolia/3/2005 (H5N1), which is more antigenically related to the challenge virus strain, in chickens. 相似文献
997.
Sun J Sugiyama A Masuda A Ochi T Takeuchi T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(9):1185-1190
The purpose of this study was to evaluate whether dityrosine and advanced oxidation protein products (AOPP) were useful as biomarkers for monitoring the development of acetaminophen-induced liver injury. Dityrosine immunoexpression in the liver along with plasma AOPP concentration was examined up to 24 hr post-acetaminophen injection in rats. The histopathological changes in the liver appeared 3 hr after acetaminophen injection and became exacerbated with time. The immunohistological expression of dityrosine was also first detected in the damaged hepatocytes 3 hr after the injection and became more accentuated at 6, 12 and 24 hr in accompanying with the elevation of plasma AOPP concentration. These results suggested that dityrosine and AOPP expressions might be useful biomarkers for monitoring the development of acetaminophen-induced liver injury. 相似文献
998.
Ohtake Y Nishizawa I Sato M Watanabe Y Nishimura T Matsubara K Nagai K Harasawa R 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(3):371-373
Nineteen blood samples collected from free-ranging wild Japanese serows, Capricornis crispus, between 2006 and 2008 in Iwate prefecture were examined for the hemoplasma infection by real-time PCR targeting the 16S rRNA gene. Five (26.3%) out of the 19 samples were positive in real-time PCR with an average melting temperature at 85.18 °C. The positive samples in the real-time PCR were reconfirmed by conventional PCR, and one of them was successful for direct DNA sequencing. The nucleotide sequence of the 16S rRNA gene of the representative stain was identical to that of Mycoplasma ovis. This was the first demonstration of hemotropic mycoplasma infections among the free-living Japanese serows in Japan. 相似文献
999.
Bannai H Tsujimura K Kondo T Nemoto M Yamanaka T Sugiura T Maeda K Matsumura T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(4):535-539
An immunoglobulin G (IgG) subclass response against equine herpesvirus type 1 (EHV-1) infection was investigated in horses that were na?ve to EHV-1/4 and those that had previously been exposed to EHV-4. The IgG subclass response was determined by an ELISA using EHV-1-specific recombinant gG protein as an antigen. In most horses na?ve to EHV-1/4, IgGa, IgGb, and IgG(T) were induced after experimental infection with EHV-1. In contrast, a subclass response dominated by IgGa and IgGb, with no apparent increase in IgG(T), was observed after EHV-1 infection in horses previously infected with EHV-4. Horses naturally infected with EHV-1 in the field showed similar responses. These results indicated that pre-infection with EHV-4 induced a Th-1-biased IgG subclass response against subsequent EHV-1 infection. 相似文献
1000.
Taketsuru H Takajo A Bao RM Hamawaki A Yoshikawa M Miyano T 《The Journal of reproduction and development》2011,57(1):99-106
There has been no culture system that supports the growth of bovine oocytes for more than 2 weeks. In the present study, bovine secondary follicles were cultured for 4 weeks, and the effects of supplemented protein components and FSH in the culture medium on the growth of the oocytes were examined. The effect of vitrification of secondary follicles on the subsequent oocyte growth was also examined. Secondary follicles (150 to 200 μm in diameter) containing growing oocytes (approximately 60 μm in diameter) were dissected from ovaries and cultured in a medium supplemented with FSH (0, 25 or 50 ng/ml) and one of the following four kinds of protein components: bovine serum albumin (BSA), bovine plasma (BPL), fetal calf serum (FCS) and bovine follicular fluid (BFF). In BSA- and BPL-supplemented media with 0 or 25 ng/ml FSH, more than 50% of follicles showed no degenerative signs during culture, and oocytes significantly increased in size after 4 weeks (P<0.05). Higher percentages of granulosa cell-enclosed oocytes were recovered from the follicles cultured in BPL-supplemented media with 0 and 25 ng/ml FSH, and the oocytes grew to 90 μm or more in diameter. In FCS- and BFF-supplemented media, FSH increased the numbers of degenerating follicles. Next, vitrified-warmed secondary follicles were cultured in BPL-supplemented medium. One third of the follicles showed no degenerative signs, and the oocytes increased in diameter to 88.8 ± 3.1 μm after 4 weeks of culture. These results suggest that a BPL-supplemented medium supports oocyte growth in bovine secondary follicles for 4 weeks, even after vitrification and warming of the follicles. 相似文献