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排序方式: 共有309条查询结果,搜索用时 15 毫秒
1.
Noriyuki Koizumi Atsushi Mori Takuya Mineta Eiji Sawada Keiji Watabe Takeshi Takemura 《Paddy and Water Environment》2017,15(4):723-730
Fecal DNA samples from the red-eared slider and Reeves’ pond turtle, suspected pests of lotus root paddies, were used to identify the plant species eaten by these turtles in order to develop a strategy for rural ecosystem conservation. The fecal samples were obtained from young and adult individuals (mostly female) of both species living in agricultural canals surrounding lotus root paddies in Tokushima Prefecture, Japan. The samples were screened for the presence or absence of DNA from nine plant species using PCR and plant species-specific primers for the rbcL gene of chloroplast DNA. In the red-eared slider, our analysis identified seven plant species in the fecal DNA samples of adults and three plant species in those of young individuals. In Reeves’ pond turtle, our analysis identified two plant species from adult fecal samples and one species from those of young individuals. Thus, adult red-eared sliders consume a greater range of plants than young red-eared sliders or Reeves’ pond turtles. Both turtle species, independently of age, consumed lotus plants and were likely to cause feeding damage to lotus roots. Considering the plant species detected in adult red-eared sliders and these plant habitats, we suggest that this adult turtle is likely to travel between the agricultural canals and the lotus root paddies. These findings will help the development of strategies for preventing damage to lotus roots by these turtles; furthermore, they indicate that fecal DNA analysis will be applicable to investigation of the feeding habits of other animal species. 相似文献
2.
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
3.
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
4.
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
5.
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
6.
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
7.
Hiromi Takahashi Chieko Kai Yasuhiro Yoshikawa Kazuya Yamanouchi 《Comparative immunology, microbiology and infectious diseases》1995,18(4):275-281
Pseudorabies virus (PRV) was inoculated intraocularly into BALB/c mice, and the distribution pattern of cells positive for several neurotransmitters and viral antigens in the eyeball, trigeminal nerve ganglia, and superior cervical ganglia was examined immunohistochemically to clarify the neural route of the virus spread. In the eyeball, substance P (SP)- and calcitonin gene-related peptide (CGRP)-positive cells were detected in the ipsilateral iris and ciliary body, neuropeptide tyrosine (NPY)-positive cells were detected in the choloid membrane, and tyrosine hydroxylase (TH)-positive cells were detected in the ipsilateral inner nuclear layer of the retina; all these cells contained viral antigens. In the superior cervical ganglia, viral antigen-positive cells containing TH or NPY were found at bilateral sites. In the trigeminal nerve ganglia, viral antigen-positive cells containing SP or CGRP were found at bilateral sites. These findings indicated that the SP- and CGRP-positive ganglion cells of the trigeminal nerve ganglia innervating the iris or ciliary body, and the NPY-positive ganglion cells of the superior cervical ganglia innervating the iris, ciliary body, and choroid membrane served as the route for the virus spread. These findings also suggested that dopaminergic neurons, such as the TH-positive retinal cells and TH-positive ganglion cells of the superior cervical ganglia, served as the route for virus spread. 相似文献
8.
Itakura S Kato H Wang PC Matsunaga A Jitsukawa T Edamura K Ohgawara H Mochizuki M Nishimura R Sasaki N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(10):1107-1109
Complement-mediated cytotoxicity for porcine islet cells (PICs) was evaluated using sera of six animal species. Then soluble complement receptor type-1 (sCR1) as an anti-complement agent was added to those sera, and the changes in 50% hemolytic unit of complement serum (CH50) and cytotoxic effect of those sera on PICs were examined. All the sera except for that of pig showed cytotoxicity. However, the extent of toxicity was considerably different between species. In the rat and human serum, sCR1 significantly reduced CH50 and cytotoxicity, however in the dog serum, sCR1 had no suppressive effects. These results may suggest that complement contribute to humoral cytotoxicity for PICs as a main factor, and the compatibility of complement with PICs differs between animal species. 相似文献
9.
Kurotaki T Narayama K Arai Y Arai S Oyamada T Yoshikawa H Yoshikawa T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(6):539-541
Histopathologic and electron microscopic observations were given on Langerhans cells (LCs) within the follicular epithelium (FE) and intradermal sweat duct (ISD) of equine "Kasen". By light microscopy, LCs were present in the greatest numbers within the FE and ISD than within the epidermal layer and the normal skin, with an occasional formation of several aggregated foci. By electron microscopy, LCs within the FE and ISD widely extended their dendritic processes between the keratinocytes and contained Birbeck granules (Bgs), mitochondria, rough endoplasmic reticula and ribosomes in the cytoplasm. Numerous Type 2 LCs, with a number of Bgs and endocytosis, and Type 3 LCs, with multivesicular bodies and endosomes of various sizes, were recognized within the FE and ISD, although inactive Type 1 LCs, with a narrow and lucid cytoplasm, were rarely seen. LCs observed within the FE and ISD in the "Kasen" skin lesions might express the particular stage corresponded to recognize, intake and process the antigens which permeate them. 相似文献
10.
Taketo Ashizawa Masashi Sasahara Atsushi Ohba Takeshi Hori Kouji Ishikawa Yukio Sasaki Tomohisa Kuroda Ryoei Harasawa Kaoru Zenbayashi-Sawata Shinzo Koizumi 《Journal of General Plant Pathology》2007,73(1):15-21
Leaf blast suppression in multilines was evaluated based on the number of susceptible lesions observed in a pure stand of
susceptible rice cultivar Sasanishiki, and in 1 : 1 and 1 : 3 mixtures of Sasanishiki and a resistant near-isogenic line,
Sasanishiki BL4 or BL7, from 1998 to 2001. The number of lesions first observed in fields in the 1 : 1 and 1 : 3 mixtures
were close to theoretical numbers calculated using the number of lesions observed in the pure stands and the ratios of the
susceptible Sasanishiki in the mixtures. The ratio of the number of lesions in the 1 : 1 and 1 : 3 mixtures to the number
in the pure stand was 0.29 and 0.09, respectively. The relationship between these ratios and the ratios of susceptible Sasanishiki
in mixtures was defined in an equation to estimate the degree of leaf blast suppression. Validation studies for the ratios
of the number of lesions in the 1 : 1 and 1 : 3 mixtures to the number in the pure stand were conducted in two different locations
and showed that the ratios are almost acceptable. The calculated autoinfection to alloinfection ratio was 1.3 and 1.4 in the
1 : 1 and 1 : 3 mixtures, respectively, suggesting that the calculated ratio will affect the degree of leaf blast suppression.
Thus, predictors were obtained to estimate leaf blast suppression for effective blast control in multilines. 相似文献