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Katsuhiro OHKOSHI Seiya TAKAHASHI Shin-ichiro KOYAMA Satoshi AKAGI Noritaka ADACHI Tadashi FURUSAWA Jun-ichiro FUJIMOTO Yoshiaki IZAIKE Tomoyuki TOKUNAGA 《Animal Science Journal》2003,74(4):269-276
In vivo matured oocytes collected by laparoscopic follicular aspiration (LFA) from hormone treated female goats were used as recipient ooplasts for somatic cell nuclear transfer (SCNT). Japanese native (Shiba) goats were used as donor females and some donor females were used repeatedly (two or three times) at intervals of a few months. To induce synchronization of estrus, a sponge containing 0.5 g of progesterone was inserted into the vagina of each goat for 14 days. These animals were also treated with follicle stimulating hormone (FSH) in a series of 8 injections over 4 days. The first FSH injection was administered on the morning of day 9 of sponge insertion. On the morning of day 13, 50 µg of gonadotropin‐releasing hormone (GnRH) was injected into each animal. Twenty‐nine hours after GnRH injection, LFA was performed. After removal of cumulus cells, collected oocytes with the first polar body were selected and enucleated for nuclear transfer. Anterior pituitary cells isolated from an adult male Shiba goat were transfected with a DNA fragment containing the enhanced green flourescent protein gene and the puromycin resistance gene. A single donor cell was inserted into the perivitelline space of each enucleated oocyte and fusion was induced with one electric pulse of 20 V for 10 µs. The SCNT goat eggs were cultured in chemically defined medium at 38.5°C in 5% CO2, 5% O2, 90% N2 for 9 days. By LFA, 396 oocytes were collected from a total of 30 females. After removal of cumulus cells, 64% of them extruded the first polar body. The percentage of SCNT goat eggs produced using in vivo matured oocytes which developed to the blastocyst stage (20–21%) was significantly higher (P < 0.05) than that produced with in vitro matured oocytes (3–8%). 相似文献
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In order to infer successional changes in structure, species composition and diversity of warm-temperate forest, we compared secondary stands regenerating after clear-felling (41–64-years old) with old-growth stands at altitudes between 300 and 800 m on Yakushima Island, southern Japan. Stem density and maximum stem diameter differed between secondary and old-growth stands, but basal area and aboveground biomass did not. At lower altitudes, the dominant species in old-growth stands with a strong sprouting capacity (Castanopsis cuspidata) also dominated secondary stands, and species composition of secondary and old-growth stands was similar. At higher altitudes, by contrast, the dominant species in old-growth stands (Distylium racemosum) had little sprouting capacity and was poorly represented in diverse secondary stands, which were dominated by Castanopsis or other less abundant species. Secondary stands had greater species diversity (Shannon–Wiener index) than old-growth stands, particularly at higher altitudes. This was due to greater species richness resulting from higher stem density per area, but not to greater evenness. We grouped the component species that share ecologically similar traits into four guilds (fagaceous, primary evergreen, secondary evergreen and deciduous species). Secondary stands were characterized by greater numbers of deciduous and secondary evergreen species. We concluded that different sprouting capacities of dominant species and different regeneration traits among guilds are responsible for the change in species composition and diversity during succession. 相似文献
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Ehab MOSSAAD Masahito ASADA Daichi NAKATANI Noboru INOUE Naoaki YOKOYAMA Osamu KANEKO Shin-ichiro KAWAZU 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):53-58
Bovine babesiosis is a livestock disease known to cause economic losses in
endemic areas. The apicomplexan parasite Babesia bovis is able to invade
and destroy the host’s erythrocytes leading to the serious pathologies of the disease,
such as anemia and hemoglobinuria. Understanding the egress mechanisms of this parasite is
therefore a key step to develop new therapeutic strategies. In this study, the possible
involvement of Ca2+ in the egress of B. bovis merozoites from
infected erythrocytes was investigated. Egress was artificially induced in
vitro using calcium ionophore A23187 and thapsigargin to increase
Ca2+ concentration in the cytosol of the parasite cells. The increased
intracellular Ca2+ concentration following these treatments was confirmed using
live cell Ca2+ imaging with confocal laser scanning microscopy. Based on our
findings, we suggest a Ca2+ signalling pathway in the egress of B.
bovis merozoites. 相似文献
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Saori MIURA Noriyuki HORIUCHI Kotaro MATSUMOTO Yoshiyasu KOBAYASHI Shin-ichiro KAWAZU Hisashi INOKUMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):883-887
Monoclonal integration of bovine leukemia virus (BLV) proviral DNA into bovine genomes
was detected in peripheral blood from two clinical cases of enzootic bovine leukosis (EBL)
without enlargement of superficial lymph nodes. A BLV-specific probe hybridized with 1 to
3 EcoRI and HindIII fragments in these 2 atypical EBL
cattle by Southern blotting and hybridization, as well as in 3 typical EBL cattle. The
probe also hybridized to a large number of EcoRI and
HindIII fragments in 5 cattle with persistent leukosis. These results
suggest that the detection of monoclonal integration of BLV provirus into the host genome
may serve as a marker of monoclonal proliferation and malignancy in difficult to diagnose
EBL cattle. 相似文献
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Kenji Asano Etsuo Shimosaka Yoko Yamashita Takashi Narabu Satoshi Aiba Itaru Sakata Kotaro Akai Satoshi Okamoto Seiji Tamiya 《Breeding Science》2021,71(3):354
Occurrence of pale potato cyst nematode, Globodera pallida (Stone) Behrens, was first recorded in Japan in 2015. Among several control measures, cultivation of resistant potato (Solanum tuberosum L.) varieties is the most effective in cost and environmental impact. As no G. pallida-resistant varieties have yet been developed in Japan, great emphasis is being placed on screening of germplasm possessing the resistance and development of the resistant varieties. In this study, we first improved previously reported DNA markers linked to the G. pallida resistance loci (GpaIVsadg and Gpa5) and then used these to screen more than 1,000 germplasms to select several candidate germplasms with resistance. We performed inoculation testing on the selected candidates and identified several resistant germplasms to the Japanese G. pallida population. Furthermore, we developed a simultaneous detection method combining three DNA markers linked to G. pallida and Globodera rostochiensis (Wollenweber) Behrens resistance loci. We validated the ability of C237-I marker to select resistant allele of GpaIVsadg and predict the presence of resistance in a Japanese breeding population. Resistant germplasms identified in this study could potentially be used to develop G. pallida-resistant varieties. The marker evaluation methods developed in this study will contribute to the efficient development of resistant varieties. 相似文献
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