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101.
Yoshikatsu Genda Kyoko Sato Osamu Nunomura Tetsuo Hirabayashi Shinya Tsuda 《Journal of General Plant Pathology》2011,77(3):201-208
The location of Pepper mild mottle virus (PMMoV) within seeds as they developed on inoculated seedlings of pepper (Capsicum annuum) was followed over time by detecting the viral coat protein using immunofluorescence microscopy. Seedlings were inoculated
with PMMoV when the flower buds on the first and second branching nodes were in bloom. Fluorescence indicating the presence
of PMMoV was first observed around immature seeds and placentas in the ovaries on the fourth branching node at 20 days post-anthesis
(20 DPA), which corresponded to 39 days post-inoculation (39 DPI). The area with fluorescence gradually expanded from the
placenta into the integument and the parenchyma, and finally reached the tip of the immature seeds by 34 DPA (53 DPI). The
embryo or endosperm beyond the endothelium never fluoresced during the experiment [i.e., ending at 81 DPA (102 DPI)]. For
visualizing viral routes of invasion from seeds into new seedlings, PMMoV-infected C. annuum seeds that were heterozygous for the L
3
tobamovirus-resistance gene were sown in soil at 30°C. After ~2 weeks, the cotyledon developed virally induced necrosis.
These findings shed light on the infection cycle of PMMoV through vertical transmission in C. annuum. 相似文献
102.
Ontogeny of digestive and immune system organs of larval and juvenile kelp grouper Epinephelus bruneus reared in the laboratory 总被引:3,自引:0,他引:3
Keitaro KATO Katsuya ISHIMARU Yoshifumi SAWADA Junichi MUTSURO Shigeru MIYASHITA Osamu MURATA Hidemi KUMAI 《Fisheries Science》2004,70(6):1061-1069
ABSTRACT: A histological examination was made of the ontogenetic development of the digestive and immune systems of the larval and juvenile kelp grouper Epinephelus bruneus reared in the laboratory. The liver, gall bladder, pancreas and the demarcating region between the intestines and rectum were formed within 3 days post-hatch (dph). During the preflexion phase (within 16 dph), revolution of the intestine concluded, and pharyngeal teeth and the mucous cells of the esophagus were differentiated. In the transitional period to the juvenile stage (25 dph), the blind sac of the stomach, gastric glands and pyloric caeca began to form. From the viewpoint of the differentiation phase of the adult-type digestive system, the kelp grouper is similar to Heterosomata, hitherto reported. The primordial thymus, kidney and spleen were present at 12, 1 and 6 dph, and the small lymphocytes in these lymphoid organs appeared at 21, 30 and 33 dph, respectively. The developmental sequence of the lymphoid organs and the appearance ages of the lymphoid organs and small lymphocytes in the lymphoid organs in the kelp grouper are similar to those of other marine fish previously reported, except for the Pacific bluefin tuna Thunnus orientalis . 相似文献
103.
Chiaki Sano Osamu Ito Tadakatsu Yoneyama Kikuo Kumazawa 《Soil Science and Plant Nutrition》2013,59(4):581-586
In the investigation of nitrogen metabolism in plants, it is important to deal with proteins, which are the end-products of nitrogen metabolism. 相似文献
104.
Yoshinobu UEMOTO Shuji SATO Chika OHNISHI Kensuke HIROSE Kenji KAMEYAMA Kazuo FUKAWA Osamu KUDO Eiji KOBAYASHI 《Animal Science Journal》2010,81(1):28-33
Leg weakness in pigs is a serious problem in the pig industry. We performed a whole genome quantitative trait locus (QTL) analysis to find QTLs affecting leg weakness traits in the Landrace population. Half-sib progeny ( n = 522) with five sires were measured for leg weakness traits. Whole genome QTL mapping was performed using a half-sib regression-based method using 190 microsatellite markers. No experiment-wide significant QTLs affecting leg weakness traits were detected. However, at the 5% chromosome-wide level, QTLs affecting leg weakness traits were detected on chromosomes 1, 3, 10 and 11 with QTL effects ranging from 0.07 to 0.11 of the phenotypic variance. At the 1% chromosome-wide level, QTLs affecting rear feet score and total leg score were detected on chromosomes 2 and 3 with QTL effects of 0.11 and 0.13 of the phenotypic variance, respectively. On chromosome 3 and 10, some QTLs found in this study were located at nearby positions. The present study is one of the first reports of QTLs affecting fitness related traits such as leg weakness traits, that segregate within the Landrace population. The study also provides useful information for studying QTLs in purebred populations. 相似文献
105.
106.
Taro Matsumoto Hiroshi Ihara Yoshinari Ishida Shinji Yamamoto Osamu Murata Yasunori Ishibashi 《Fish physiology and biochemistry》2010,36(1):63-70
Although chub mackerel (Scomber japonicus) is widely distributed all over the world, the relevance of its visual sensitivity to its ecology is not yet fully understood.
We investigated spectral sensitivity in juvenile chub mackerel in the range of ultraviolet (UV) to visible light (369–652 nm)
by electroretinogram (ERG) using light-emitting diodes (LEDs). Sensitivity peaked at a wavelength of approximately 482 nm
in dark-adapted fish and 525 nm in light-adapted fish. A secondary sensitivity peak in the UV range at approximately 382 nm
was found in both dark- and light-adapted fish. The UV sensitivity of chub mackerel may be attributable to UV transmissibility
of the optical media and to the presence of a beta-band of visible light-sensitive visual pigments, and not to an alpha-band
of UV visual pigments. This UV sensitivity may be useful for feeding or communication with other fishes. 相似文献
107.
Recent studies have shown that the incorporation of ammonium nitrogen into amino acids in the leaves is strictly dependent on light (1-4). It is speculated that the effect of light on ammonium assimilation may be through the synthesis of the precursors of amino acids, or by the supply of the energy required for amination and amidation with organic acids. In the Vicia faba chloroplasts Givan et al. (1) exhibited that the synthesis of glutamic acid from a-ketoglutarate was linked with the generation of reduced pyridin nucleotide by photosynthetic electron transport. Mitchell and Stocking (2) suggested the direct coupling of glutamine formation with photophosphorylation in the pea chloroplasts. On the other hand. the processes of nitrate assimilation are more indebted to light than those of ammonium assimilation, because the former ones involve the reduction of nitrate to ammonium which is believed to be light-dependent (5). Canvin and Atkins (6). and Atkins and Canvin (7) reported that the incorporation of 15N-labeled ammonium and nitrate into amino acid fractiom was depressed by the dark treatment and by photosystem inhibitors; 3-(3′,4′-dichlrophenyl)-1-1-dimethylurea (DCMU) and carbonyl-cyanide-m-chlorophenyl-hydrazone(CCCP). 相似文献
108.
Hiraku SASAKI Osamu KITAZUME Jun NONAKA Kenji HIKOSAKA Kenichi OTAWA Kikuji ITOH Yutaka NAKAI 《Animal Science Journal》2006,77(5):545-548
We observed the effects of a commercial microbiological additive (MA) on the beef manure composting process and investigated the changes in its physical and chemical components and microbial populations in the composting process. When beef manure compost was inoculated with the MA, its temperature rapidly increased at the beginning of the process, and after the first turning, the ammonia emission from the compost pile and nitrate production decreased quicker than that in the composting process without the MA. During the composting process, the manure inoculated with MA showed a larger numbers of mesophilic and thermophilic aerobes, and a smaller number of thermophilic anaerobes than in the process without the MA. These results suggested that mesophilic aerobes increased in number and metabolized ammonia by assimilation rather than nitrification to accelerate the temperature elevation in the composting process with the MA. 相似文献
109.
Yuuto KAWASHIMA Ayako FUJIMOTO Morihiro SAITO Osamu MIKAMI Yoshiharu ISHIKAWA Koichi KADOTA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(6):968
The histology and immunohistochemistry of pleomorphic and conventional epithelioid mesotheliomas were examined. The former was detected in two young calves aged 2 and 4 months and was characterized by pleomorphic and atypical cells with decreased expression of cytokeratin 7 (CK7). In contrast, the latter was found in a 31-month-old heifer, consisting of tumor cells uniform in size and shape with CK7 expression in nearly all cells. Production of collagen by tumor cells was demonstrated in both histological types, and was considered to be characteristic of bovine epithelioid mesothelioma. Pleomorphic mesothelioma is far more pleomorphic and mitotically active than conventional mesothelioma, and its normal counterpart may be immature mesothelial cells with high proliferation potential, which exist in fetal life and early calfhood. 相似文献
110.