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141.
Yamamoto Y Ishikawa R Omoe K Yoshikawa N Yamaguchi-Yamada M Taniguchi K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(3):265-271
The inwardly rectifying K+ channels, Kir1.1, Kir2.3 and Kir4.1-Kir5.1, are the candidate chemosensory molecules for CO2/H+. We determined the mRNA expression and immunohistochemical localization of these channels in the medulla oblongata of the rat. RT-PCR analysis revealed mRNAs of Kir1.1, Kir2.3, Kir4.1 and Kir5.1 were detected in the medulla. The immunoreactivities for Kir1.1, Kir2.3, Kir4.1, and Kir5.1 were observed in the medulla, and immunolabeling pattern was varied by the subunit. Immunoreactivities for Kir1.1 and Kir2.3 were observed in the nerve cell bodies and glial cells both in the chemosensory areas [nucleus tractus solitarius (NTS), nucleus raphe obscurus (RO), pre-B?tzinger complex (PreB?tC)] and non-chemosensory area [hypoglossal nucleus (XII), inferior olive nucleus (IO)]. Kir4.1 immunoreactivity was observed in the glial cells and neuropil, especially in XII and IO. Kir5.1 immunoreactivity was observed in the nerve cell bodies in the XII, RO, and PreB?tC, but not in the NTS or IO. In the NTS, a dense network of varicose nerve fibers showed immunoreactivity for Kir5.1. Our findings suggest that Kir channels may not act specific to the central chemoreception, but regulate the ionic properties of cellular membranes in various neurons and glial cells. 相似文献
142.
Amphiploids were produced from pentaploid hybrids between Vaccinium corymbosum (4x) and Vaccinium ashei (6x) by colchicine treatment. Seeds of each parental species and those obtained by the interspecific crossing were treated with colchicine at 0, 500, 1000 and 2000 mg/l for 7 days, and the ploidy level of the seedlings was determined with flow cytometry. Either amphiploid (10x) or ploidy chimera (5x + 10x) was obtained from interspecific hybrid seeds treated with all colchicine concentrations, while no chromosome-doubled plants were obtained from both parents. Cross direction in interspecific hybridization affected the results of colchicine treatment and amphiploids were obtained only when V. corymbosum was used as the seed parent. In this cross, 17–25% of the seedlings turned to be amphidiploids or ploidy chimeras by treating with 500 mg/l colchicines for 7 days. These results indicate that susceptibility to colchicine may increase in the interspecific hybrid compared with the parental species but only when V. corymbosum was used as female parent. 相似文献
143.
Hiroto Murase Atsushi Kawabata Hiroshi Kubota Masayasu Nakagami Kazuo Amakasu Koki Abe Kazushi Miyashita Yoshioki Oozeki 《Fisheries Science》2012,78(4):761-773
The distribution pattern and biomass of the Japanese anchovy Engraulis japonicus in the offshore region of the western North Pacific (north of 35°N and west of 170°E) were studied using a quantitative echosounder. This is the first attempt at such a study in this region. Data were collected in summer from 2004 to 2007. The biomass was estimated using data collected at 38?kHz. Species compositions in the backscatterings from pelagic fish were assigned based on the results of trawl hauls taking account of sea surface temperature (SST). Japanese anchovy tended to be high density to the west of 153°E and were distributed in an SST range of 9?C24?°C. Although the temporal and spatial coverage of the survey differed each year, at least 1.5?C3.4 million tons of Japanese anchovy were present in the survey area between 2004 and 2007. To take account of the spatial coverage of the survey each year, the most reliable biomass estimate for this region in the time period was 3.4 million tons (coefficient of variation?0.22). 相似文献
144.
T. O. Oswald Adissin Ishikawa Manabu Koshio Shunsuke Yokoyama Saichiro Amina S. Moss Serge Dossou 《Aquaculture Nutrition》2020,26(1):186-200
The current study evaluated the effects of fish oil replacement with eicosapentaenoic acid‐enriched single‐cell microalgae in the diets of larval and postlarval kuruma shrimp. Experimental diets containing different level of Nannochloropsis sp. powder (10, 40, 70 g/kg) and lipids (2, 8, 10, 14, 35, 58 g/kg) were evaluated. The substitution of fish oil with algal powder significantly improved shrimp growth compared to that in the control group, with the highest final body weight recorded at 70 g/kg in larvae and 40 g/kg in postlarvae. Larvae fed algal lipids with a dry weight percentage in the diet of greater than 10 g/kg showed significantly lower performance than those in the control group. The neutral lipids in the tissue of the postlarvae that had been fed algal lipids had an improved fatty acid profile, as the content of highly unsaturated fatty acids increased compared to that in the other groups. The content of docosahexaenoic acid increased in the tissue, indicating the possible occurrence of the metabolism and accumulation of Nannochloropsis sp. essential fatty acids. Algal powder could replace FO up to 140 g/kg in shrimp diets without compromising growth and FA profiles. 相似文献
145.
Yousuke Taoka Hiroto Maeda Jae-Yoon Jo Su-Mi Kim Soo-Il Park Takeshi Yoshikawa Taizo Sakata 《Fisheries Science》2006,72(4):755-766
ABSTRACT: To investigate the effect of live and dead probiotic cells on the non-specific immune system of tilapia Oreochromis niloticus , probiotics were introduced by feeding either in the form of live or dead cells, or supplying live cells to the rearing water in a closed recirculating system. The probiotics treatment enhanced non-specific immune parameters such as lysozyme activity, migration of neutrophils and plasma bactericidal activity, resulting in improvement of resistance to Edwardsiella tarda infection. Especially, oral administration of live cells seemed to be more effective compared with other probiotic treatments such as oral administration of dead probiotic cells and supply of live probiotic cells to the rearing water. These results indicate that probiotics treatment is promising as an alternative method to antibiotics for disease prevention in aquaculture, and the viability of probiotic bacteria is a key factor to induce more potential effect of probiotics used for fish production. 相似文献
146.
Satoshi Kitao Takatsugu Yamada Takefumi Ishikawa Hiroo Madarame Mitsuru Furuichi Sakurako Neo Ryo Tsuchiya Kosaku Kobayashi 《Journal of veterinary diagnostic investigation》2006,18(3):291-295
Serum alpha-fetoprotein (AFP) concentrations were measured before and after surgical removal of tumor masses in four dogs with hepatocellular carcinoma (HCC). Localization of AFP was also examined immunohistochemically in tumor tissues. In three cases, the serum AFP concentration was 10 to 20 times higher than that of normal dogs. One to two months after surgery, the serum AFP concentration had decreased to normal range. AFP was localized in the tumor tissues in these three cases. One case, which had a low serum AFP, did not show AFP localization in tumor tissue. 相似文献
147.
Shinji Yamamoto Yoshihiro Wada Yoshiharu Ishikawa Koichi Kadota 《Journal of veterinary diagnostic investigation》2007,19(4):447-450
A newborn Holstein female calf had neoplastic lesions in the skin and within the thoracic and abdominal cavities but not in the bone marrow, spleen, thymus, or most lymph nodes. Because the tumor cells were positive for CD79a (B cell marker), CD5 (B-1 cell marker) and terminal deoxynucleotidyl transferase (marker for immature lymphoid precursors), a diagnosis of precursor B-1 B cell lymphoma was made. The diagnosis was strongly supported by the fact that B-1 cells can develop in the fetus, unlike B-2 cells, which are produced after birth. The lymphoma was distinct from the typical calf form of lymphoma of B-2 cell origin, which does not express CD5 and is characterized by generalized lymphadenopathy and involvement of the bone marrow, blood and spleen. 相似文献
148.
Von Yoh-Ichi Miyake Tsune Ishikawa Keiichiro Kawata 《Reproduction in domestic animals》1979,14(4):145-150
Contents: Three mares that had heen diagnozed clinically as sterile were cytogenetically investigated. For each o f the mures 63 or more metaphases were analyzed (63 metaphases in one case, 72 metaphases in the 2nd case and 90 rnetaphases in the 3rd case). Only the sex chromosomal monosomy (63, X) were detected in each of the metaphases. Using the G-banding technique unpairing X-chromosomes, was accurately distinguished from autosomes nos. 1 and 2. The incidence of drumstick was 0.5 76 and 0.2 % respectively in two cases. The most obvious clinical abnormality was gonadal dysgenesis, which was observed in all mares. N o clear-cut oestrus symptoms were detectable despite repeated treatment with various hormones. 相似文献
149.
150.