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Seiju Ishikawa 《Journal of General Plant Pathology》2004,70(5):249-255
Simple diagnosis by ethanol immersion (SDEI) to detect Glomerella cingulata was used to detect three other fungi that also cause latent infection of strawberry plants. Signs on strawberry leaves with asymptomatic latent infection by Colletotrichum acutatum became visible using SDEI. Salmon-pink conidial masses were produced in the acervuli on the treated leaves 5 days after incubation at 28°C. In the case of Dendrophoma obscurans, pycnidia with amber conidial masses formed 5 days after incubation at 28°C. The pycnidia were observed mainly on the ribs, and conidial masses exuded from the ostiole. These macroscopic conidial masses were similar to those of G. cingulata and C. acutatum. When water was dripped onto a lesion caused by D. obscurans, the pycnidia exuded white filamentous conidial masses, making the distinction of D. obscurans from G. cingulata or C. acutatum. On petioles with latent infection by Fusarium oxysporum f. sp. fragariae, white aerial hyphae grew out from the vascular tissues on the cut surface 3 days after incubation at 28°C and were easily observed by eye or with a loupe. Thus, SDEI was also useful for diagnosing latent infection of strawberry plants by C. acutatum, D. obscurans, and F. oxysporum f. sp. fragariae. 相似文献
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Hiroshi UENO Osamu YAMATO Takeshi SUGIURA Moeko KOHYAMA Akira YABUKI Kenjiro MIYOSHI Kazuya MATSUDA Tsuyoshi UCHIDE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(1):91-95
A male Japanese domestic cat with retarded growth in Hokkaido, Japan, showed
progressive motor dysfunction, such as ataxia starting at 3 months of age and tremors,
visual disorder and seizure after 4 months of age. Finally, the cat died of neurological
deterioration at 9 months of age. Approximately half of the peripheral blood lymphocytes
had multiple abnormal vacuoles. Magnetic resonance imaging showed bisymmetrical
hyperintensity in the white matter of the parietal and occipital lobes in the forebrain on
T2-weighted and fluid-attenuated inversion recovery images, and mild encephalatrophy of
the olfactory bulbs and temporal lobes. The activity of lysosomal acid β-galactosidase in
leukocytes was negligible, resulting in the biochemical diagnosis of GM1 gangliosidosis.
Histologically, swollen neurons characterized by accumulation of pale, slightly granular
cytoplasmic materials were observed throughout the central nervous system. Dysmyelination
or demyelination and gemistocytic astrocytosis were observed in the white matter.
Ultrastructually, membranous cytoplasmic bodies were detected in the lysosomes of neurons.
However, genetic analysis did not identify the c.1448G>C mutation, which is the single
known mutation of feline GM1 gangliosidosis, suggesting that the cat was affected with a
new variant of the feline disease. 相似文献
6.
Satoshi Furukawa Naho Tsuji Seigo Hayashi Yusuke Kuroda Masayuki Kimura Chisato Hayakawa Kazuya Takeuchi Akihiko Sugiyama 《Journal of toxicologic pathology》2022,35(1):37
We investigated the morphological effects of testosterone on placental development in a rat model of polycystic ovarian syndrome (PCOS). Testosterone propionate (TP), which was subcutaneously administered to pregnant rats with 5 mg/animal from gestation day (GD) 14 to GD 18, induced a maternal weight reduction without mortality or clinical signs from GD 19 onwards. A decrease in fetal and placental weight, an increase in intrauterine growth retardation (IUGR) rates, and histological changes in the placenta were observed on GD 21 but not on GD15 or 17. Histopathologically, on GD 21, the trophoblast septa thickened, and the maternal sinusoids were narrowed in the labyrinth zone, resulting in a small placenta. Additionally, the placental weight, thickness, and histological morphology in the labyrinth zone on GD 21 in the TP-treated group were nearly identical to those on GD 17 in the control and TP-treated groups. Therefore, it was assumed that the testosterone-induced small placenta was induced in association with the developmental inhibition of the fetal part of the placentas from GD 17 onwards. 相似文献
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ABSTRACT: As a possible factor leading to the low recruitment level of sea urchins in kelp forests, the inhibitory effect of 2,4-dibromophenol (DBP) and 2,4,6-tribromophenol (TBP) released from the large perennial brown algae Ecklonia kurome and Eisenia bicyclis on survival and metamorphosis of eight-armed larvae of the sea urchin Strongylocentrotus nudus was examined. The percentage of larvae that underwent metamorphosis in filtered sea water after 1 h exposure to one-half dilution of saturated dibromomethane solution (∼60 ppm) as a chemical inducer reached approximately 100% after 1 h, while that in filtered sea water containing 1 ppm TBP was reduced to 73%. This was further reduced to less than 40% in the presence of 10 and 20 ppm TBP after 2 h. In filtered sea water containing 1 and 10 ppm DBP, the proportion of metamorphosed larvae was reduced markedly to 43 and 5% after 2 h, respectively. All larvae exposed to 50 ppm TBP and to 20 and 50 ppm DBP died after 1 h. These findings suggest that DBP is more toxic than TBP for sea urchin larvae, strongly inhibiting their metamorphosis. 相似文献
8.
Akihiko Yatsu Tomowo Watanabe Junta Mori Kazuya Nagasawa Yukimasa Ishida Toshimi Meguro Yoshihiko Kamei & Yasunori Sakurai 《Fisheries Oceanography》2000,9(2):163-170
Variability in catch-per-unit-effort (CPUE) was examined for the autumn cohort of Ommastrephes bartramii collected with research driftnets during 1979–1998 along five longitudinal transects passing through the Subarctic, Transitional and Subtropical Domains in the North Pacific. CPUE was generally low during the period of intensive commercial driftnet fishing (1980–1992) and increased following the 1992 moratorium on the use of large-scale driftnets. However, CPUE levels were low for the cohorts hatched in 1992 and 1996 (captured in subsequent years owing to a one-year life of O. bartramii ) that experienced low sea surface temperatures from hatching to recruitment. Among similar-aged squid collected from 180° and 179°30'W in June, mantle lengths were significantly greater in 1997 than during 1995–96. These findings suggest that the driftnet fishery and sea surface temperatures from hatching to recruitment strongly affected stock abundance and possibly growth. 相似文献
9.
The utilization of oleic acid as an energy source and the effects of oleic acid levels and/or dietary soy bean lecithin (SBL) on oleic acid utilization, growth and survival, and lipid class and fatty acid compositions of freshwater prawn, Macrobrachium rosenbergii (de Man), juveniles were determined.
Increase in levels of dietary oleic acid from 10 to 80 g kg−1 significantly ( P ≤ 0.05) reduced growth, survival and feed conversion efficiency of M. rosenbergii juveniles during the 40-day feeding period. Inclusion of 20 g kg−1 SBL had no significant effect ( P ≥ 0.05) on growth and survival, nor was there any interactive effect between dietary SBL and oleic acid levels.
Body fatty acid profile of prawns reflected dietary fatty acid quantity. The fatty acid composition of prawns fed diets containing 80 g kg−1 oleic acid had tremendously high proportions of oleic acid. Polar lipids, mostly phosphatidylcholine (PC), constituted the bulk of the extracted total lipids. Prawns fed with SBL had significantly ( P ≥ 0.05) higher PC content.
Oleic acid was metabolized for energy by M. rosenbergii juveniles at the same rate regardless of dietary level of SBL and/or oleic acid. Expired14 CO2 accounted for half of the ingested radioactivity 48 h after feeding with labelled diets. No significant difference in the amount of 14 CO2 expired by prawns fed the labelled test diets was found. Per cent radioactivity ingested and absorbed into the body was also not significantly different in prawns of the different dietary treatments. 相似文献
Increase in levels of dietary oleic acid from 10 to 80 g kg
Body fatty acid profile of prawns reflected dietary fatty acid quantity. The fatty acid composition of prawns fed diets containing 80 g kg
Oleic acid was metabolized for energy by M. rosenbergii juveniles at the same rate regardless of dietary level of SBL and/or oleic acid. Expired
10.
Interannual variations in abundance, timing of outmigration from rivers, growth rate and condition of juvenile chum salmon
(Oncorhynchus keta) were studied in the Nemuro Strait (eastern Hokkaido, Japan) during 1999–2002 to establish a possible relationship to zooplankton
abundance. The otolith microstructure of juveniles was examined each year in late June to determine their time and size at
sea entry (i.e., outmigration), and to estimate the early marine growth rates. Salmon outmigration peaked in mid- or late
May, which coincided, in three of the four study years, with the peak release of juveniles into rivers within the study area.
Abundance, growth rate and condition of fish were higher in 2001, when—compared to other years—smaller fish experienced higher
growth rates, coinciding with greater zooplankton abundance for that year. Our results suggest that high zooplankton abundance
positively influenced juvenile chum salmon growth and the condition of the fish during their early marine life despite their
small size at sea entry. 相似文献