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981.
Katsunori Tanaka Yukari Akashi Kenji Fukunaga Tatsuya Yamamoto Yasheng Aierken Hidetaka Nishida Chun Lin Long Hiromichi Yoshino Yo-Ichiro Sato Kenji Kato 《Breeding Science》2013,63(2):183-196
Molecular analysis encouraged discovery of genetic diversity and relationships of cultivated melon (Cucumis melo L.). We sequenced nine inter- and intra-genic regions of the chloroplast genome, about 5500 bp, using 60 melon accessions and six reference accessions of wild species of Cucumis to show intra-specific variation of the chloroplast genome. Sequence polymorphisms were detected among melon accessions and other Cucumis species, indicating intra-specific diversification of the chloroplast genome. Melon accessions were classified into three subclusters by cytoplasm type and then into 12 subgroups. Geographical origin and seed size also differed between the three subclusters. Subcluster Ia contained small-seed melon from Southern Africa and South and East Asia and subcluster Ib mainly consisted of large-seed melon from northern Africa, Europe and USA. Melon accessions of subcluster Ic were only found in West, Central and Southern Africa. Our results indicated that European melon groups and Asian melon groups diversified independently and shared the same maternal lineage with northern African large-seed melon and Southern African small-seed melon, respectively. Cultivated melon of subcluster Ic may have been domesticated independently in Africa. The presence of 11 cytoplasm types in Africa strongly supported African origin of cultivated melon and indicated the importance of germplasm from Africa. 相似文献
982.
Hidekazu Sato Kyu-Oh Kim Han-Ki Kim Byoung-Suhk Kim Yuji Enomoto Ick-Soo Kim 《Fibers and Polymers》2010,11(8):1123-1127
We reported the preparation and characterization of the poly(vinyl alcohol) (PVA)/BaSO4 hybrid nanofibers prepared by normal and ultrasonic electrospinning, respectively. Compared to normal electrospinning, BaSO4 particles in the resultant PVA/BaSO4 hybrid nanofibers prepared by ultrasonic electrospinning were well-dispersed without severe agglomerations, as confirmed by scanning electron microscopy (SEM) analysis. X-ray diffraction (XRD) analysis indicated that typical crystalline peaks of PVA and BaSO4 particles were dramatically decreased by ultrasonication during electrospinning. Moreover, the size of BaSO4 aggregates became smaller. 相似文献
983.
Koji Satsuma 《Pest management science》2010,66(8):847-852
BACKGROUND: Linuron is a globally used phenylurea herbicide, and a large number of studies have been made on the microbial degradation of the herbicide. However, to date, the few bacteria able individually to mineralise linuron have been isolated only from European agricultural soils. An attempt was made to isolate linuron‐mineralising bacteria from Japanese river sediment using a uniquely designed river ecosystem model (microcosm) treated with 14C‐ring‐labelled linuron (approximately 1 mg L?1). RESULTS: A linuron‐mineralising bacterium that inhabits river sediment was successfully isolated. The isolate belongs to the genera Variovorax and was designated as strain RA8. Strain RA8 gradually used linuron in basal salt medium (5.2 mg L?1) with slight growth. In 15 days, approximately 25% of 14C‐linuron was mineralised to 14CO2, with 3,4‐dichloroaniline as an intermediate. Conversely, in 100‐fold diluted R2A broth, strain RA8 rapidly mineralised 14C‐linuron (5.5 mg L?1) and more than 70% of the applied radioactivity was released as 14CO2 within 3 days, and a trace amount of 3,4‐dichloroaniline was detected. Additionally, the isolate also degraded monolinuron, metobromuron and chlorobromuron, but not diuron, monuron or isoproturon. CONCLUSION: Although strain RA8 can grow on linuron, some elements in the R2A broth seemed significantly to stimulate its growth and ability to degrade. The isolate strictly recognised the structural difference between N‐methoxy‐N‐methyl and N,N‐dimethyl substitution of various phenylurea herbicides. Copyright © 2010 Society of Chemical Industry 相似文献
984.
Kuniyoshi Yasukawa Shiori Saito Takuya Kubo Yuya Shibasaki Kayo Yamaoka Hisae Hachimura Tomoko Kuyama Akiteru Amimoto Tsuyoshi Kumata Yuko Kitahara Masahiko Takenaka Hitoshi Matsumura Takehiro Uno Tomiya Uchino Kazutaka Takehara Kouji Nishida Michiyo Kadoya Masafumi Sato Kaoru Kato Kanako Matsumoto Satoshi Saito Tetsuya Shimoda 《Veterinary dermatology》2010,21(1):42-49
The purpose of this study was to investigate the minimum effective dose of recombinant canine interferon-γ (rCaIFN-γ) for the treatment of dogs with atopic dermatitis (AD). Thirty-four dogs with AD from 17 animal hospitals in Japan were administered half or one-fifth of the approved rCaIFN-γ dose of 10 000 units/kg, three times a week for 4 weeks, followed by once weekly for an additional 4 weeks. Pruritus, excoriation, erythema and alopecia were evaluated and scored by the investigators on weeks 2, 4, 6, 8 and 12. The efficacy rate (number of excellent cases + number of good cases/total number of cases) at week 8 in the 2000 units/kg group was 36.4% for pruritus, 36.4% for excoriation, 45.5% for erythema and 36.4% for alopecia. In contrast, in the 5000 units/kg group, the efficacy rate was 64.3% for pruritus, 57.1% for excoriation, 78.6% for erythema and 78.6% for alopecia. The efficacy rate of the 5000 units/kg group was high for all signs evaluated and comparable to that of the 10 000 units/kg group reported in a previous study. The results of this study showed that 2000 units/kg of rCaIFN-γ is less effective than 5000 units/kg to treat dogs with AD, and the efficacy of the 5000 units/kg dose is comparable to that of 10 000 units/kg at week 8. 相似文献
985.
Granulosa cell ligand NPPC and its receptor NPR2 maintain meiotic arrest in mouse oocytes 总被引:3,自引:0,他引:3
Granulosa cells of mammalian Graafian follicles maintain oocytes in meiotic arrest, which prevents their precocious maturation. We show that mouse mural granulosa cells, which line the follicle wall, express natriuretic peptide precursor type C (Nppc) messenger RNA (mRNA), whereas cumulus cells surrounding oocytes express mRNA of the NPPC receptor NPR2, a guanylyl cyclase. NPPC increased cGMP levels in cumulus cells and oocytes and inhibited meiotic resumption in vitro. Meiotic arrest was not sustained in most Graafian follicles of Nppc or Npr2 mutant mice, and meiosis resumed precociously. Oocyte-derived paracrine factors promoted cumulus cell expression of Npr2 mRNA. Therefore, the granulosa cell ligand NPPC and its receptor NPR2 in cumulus cells prevent precocious meiotic maturation, which is critical for maturation and ovulation synchrony and for normal female fertility. 相似文献
986.
Atsushi Sakai Takeshi Sakai Shigeo Kuramoto Shigeho Sato 《Journal of Forest Research》2010,15(5):316-327
To profile secondary succession after clearcutting a conifer plantation, we examined the composition of the soil seed bank
and the process of vegetation recovery after clearcutting a mature Hinoki (Chamaecyparis obtusa) plantation in southwest Japan. We set up two study plots and collected 25 and 26 soil samples (each 20 cm × 30 cm × 5 cm
depth), respectively, in April 1999, before clearcutting. Using the seedling emergence method, we detected 500–839 buried
viable seeds m−2 in 42–44 species. Soil seed banks in both plots contained typical pioneer species but few late-successional species. After
clearfelling the plantation in June 1999, we censused seedling establishment for 4 years and the composition of the vegetation
for 6 years. More than half of the seedlings emerged in the second year, suggesting that the timing of clearcutting is possibly
critical to seedling establishment. Nineteen plant species disappeared after clearcutting, 40 species were retained and 43
species newly emerged after clearcutting. Most of the newly emerged species were pioneer species which originated in the soil
seed bank. Seven of the pioneer species, as typified by Rubus crataegifolius, showed clonal growth from the third year after clearcutting. Japanese serow browsed the seedlings of major pioneer species,
possibly affecting the process of secondary succession. Late-successional species such as Abies firma declined in coverage or disappeared after clearcutting. Our results suggest that the soil seed bank makes a major contribution
to vegetation recovery after clearcutting, but possibly not to restoration of the late-successional species. 相似文献
987.
Differences in the biochemical compositions of two dietary jellyfish species and their effects on the growth and survival of Ibacus novemdentatus phyllosomas
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Phyllosomas (planktonic larvae) of slipper lobsters cling onto and feed on jellyfish under both natural and laboratory conditions. Phyllosomas of Ibacus novemdentatus are capable of feeding on various jellyfish species including venomous stingers; however, the range of jellyfish species capable of supporting the growth and survival of phyllosomas is unknown. Seventeen (12 for the first and five for the second trials) and 18 (13 for the first and five for the second trials) phyllosomas were fed exclusively on the jellyfish Aurelia aurita and Chrysaora pacifica, respectively. Aurelia aurita‐fed phyllosomas metamorphosed into the nisto stage (postbenthic larvae) ~54 days after hatching, whereas C. pacifica‐fed phyllosomas did not. Major nutritional compositions such as amino acids, fatty acids and minerals were compared between the two jellyfish species. The proportion of each major nutritional component was not significantly different between the two jellyfish species, suggesting that C. pacifica was not nutritionally inferior to A. aurita. Therefore, the observation that the C. pacifica‐fed phyllosomas did not metamorphose into the nisto stage was not because of major nutritional compositions but due to other factors such as the lack or excess of other minor nutrients, or the species‐specific texture of the jellyfish. 相似文献
988.
989.
990.
Masatoshi Ban Hiroyuki Nagoya Shunpei Sato Hirohumi Yaegashi Masaki Ichimura Nobuhiro Sato 《Fisheries Science》2013,79(6):967-975
We evaluated the potential for hybridization between Atlantic salmon and salmonids currently present in Japan. We performed artificial and natural crosses and tested for hybridization using short interspersed elements. We documented the occurrence of hybrids and gynogenesis following artificial crossing. However, the survival rate of these offspring was low (<2 % to the fry stage). We were unable to obtain viable offspring from natural crosses of Atlantic salmon and chum salmon or masu salmon. Our results suggest that there is little risk of hybridization between Atlantic salmon and salmonids that are currently present in the wild in Japan. Furthermore, our results suggest that gynogenesis may occur naturally. 相似文献