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331.
332.
Michiko NAKAI Manabu OZAWA Naoki MAEDOMARI Junko NOGUCHI Hiroyuki KANEKO Junya ITO Akira ONISHI Naomi KASHIWAZAKI Kazuhiro KIKUCHI 《The Journal of reproduction and development》2014,60(3):256-259
In pigs, the embryonic developmental ability after intracytoplasmic sperm injection (ICSI) is inferior to that resulting from
in vitro fertilization (IVF). We evaluated the timing of cell division up to blastocyst formation on
embryonic development after ICSI using either whole sperm (w-ICSI) or the sperm head alone (h-ICSI) and IVF as a control. At
10 h after ICSI or IVF, we selected only zygotes, and each of the zygotes/embryos was evaluated for cleavage every 24 h until
168 h. We then observed a delay in the 1st and 2nd cleavages of h-ICSI embryos and also in blastocoele formation by w-ICSI
embryos in comparison with IVF embryos. The rate of blastocyst formation and the quality of blastocysts in both ICSI groups
were inferior to those in the IVF group. In conclusion, the delay in cleavage of porcine ICSI embryos shows poorer embryonic
development. 相似文献
333.
Lipid class and fatty acid composition of phospholipids from the gonads of skipjack tuna 总被引:1,自引:0,他引:1
Seiichi HIRATSUKA Tomoko KITAGAWA Yoko MATSUE Masayuki HASHIDUME Shun WADA 《Fisheries Science》2004,70(5):903-909
ABSTRACT: Lipid class and fatty acid composition of phospholipids from the gonads of skipjack tuna were examined to evaluate effective utilization of the processing of by-products. The predominant phospholipids in the ovaries were phosphatidylcholine (PC; 47.9%), phosphatidylethanolamine (PE; 19.3%) and lyso-phosphatidylcholine (LPC; 19.1%). In contrast, those in the testes were PC (40.1%), PE (29.3%) and phosphatidylserine (PS; 9.6%). The percentage of docosahexaenoic acid (DHA) was markedly high at more than 50% in LPC of the ovaries, and PE and PS of the testes were also high. The percentages of DHA at sn-position 2 of the predominant phospholipids, except for PC in the testes, were more than 60%, in particular PE in the testes was remarkably high at 81.9%. After storage for 2 days at 5°C, the LPC content in the ovaries increased twofold and the DHA level of LPC was the same as before, though the contents of other phospholipids decreased. 相似文献
334.
Effects of water temperature on early development of Japanese eel <Emphasis Type="Italic">Anguilla japonica</Emphasis> 总被引:2,自引:0,他引:2
Akihiro Okamura Yoshiaki Yamada Noriyuki Horie Tomoko Utoh Naomi Mikawa Satoru Tanaka Katsumi Tsukamoto 《Fisheries Science》2007,73(6):1241-1248
ABSTRACT: To determine an optimal temperature range for efficient production of healthy eel larvae Anguilla japonica , the effect of water temperature on hatching, survival, and deformity rates was examined. The early ontogeny of morphological features in this species by incubating eggs at five different temperatures (19, 22, 25, 28 and 31°C) was examined. Hatching occurred at 24, 28, 46 and 58 h after fertilization when incubated at 28, 25, 22 and 19°C, respectively; no eggs hatched at 31°C. The growth rate of prefeeding larvae increased as water temperature was elevated and acquisition of feeding ability was also accelerated at higher temperature. Significantly high hatching rates (76–86%, P < 0.05) and survival rates (61–86%, P < 0.05) were observed at relatively high temperatures (22–28°C). The deformities were 'open lower jaw', 'pericardial edema', and 'notochordal bending', in which the mouth was deformed with a downward projecting lower jaw, the pericardial cavity was swollen, and the notochord was bent or twisted to various degrees, respectively. Open lower jaw and pericardial edema were especially predominant at 19°C, with rates of 68 and 92%, respectively, compared with 31 and 10% at 25 and 28°C, respectively. The occurrence of notochordal bending was not affected by temperature. The optimal temperature for incubation and rearing A. japonica eggs and prefeeding larvae is approximately 25–28°C. 相似文献
335.
Shibata K Nakamura T Matsumoto T Otsuji K Okamoto TJ Nishizuka N Kawate T Watanabe H Nagata S Ueno S Kitai R Nozawa S Tsuneta S Suematsu Y Ichimoto K Shimizu T Katsukawa Y Tarbell TD Berger TE Lites BW Shine RA Title AM 《Science (New York, N.Y.)》2007,318(5856):1591-1594
The heating of the solar chromosphere and corona is a long-standing puzzle in solar physics. Hinode observations show the ubiquitous presence of chromospheric anemone jets outside sunspots in active regions. They are typically 3 to 7 arc seconds = 2000 to 5000 kilometers long and 0.2 to 0.4 arc second = 150 to 300 kilometers wide, and their velocity is 10 to 20 kilometers per second. These small jets have an inverted Y-shape, similar to the shape of x-ray anemone jets in the corona. These features imply that magnetic reconnection similar to that in the corona is occurring at a much smaller spatial scale throughout the chromosphere and suggest that the heating of the solar chromosphere and corona may be related to small-scale ubiquitous reconnection. 相似文献
336.
Md. Sharif Hossen Itaru Sotome Kazuko Nanayama Tomoko Sasaki Hiroshi Okadome 《Cereal Chemistry》2016,93(1):53-57
The digestibility and hydration properties of wet‐ground submicron‐scale rice flour were compared with those of dry‐ground coarser microscale flours. The submicron flour (mean size 0.6 µm) was produced in a wet‐media mill with 0.3 mm zirconia beads by continuous 24 h pulverization. The solubility, water absorption index, and swelling power increased as the mean particle size decreased, reaching maximum values in the submicron flour. Starch damage was high in the submicron flour, with the absence of intact starch granules. The digestibility also increased as the particle size decreased, and it was highest in the submicron flour. These results show that wet‐ground submicron rice flour has different functional properties from dry‐ground coarser flour. The digestibility was more strongly influenced by starch damage and the water absorption index than by the mean particle size. 相似文献
337.
Tomoko Hashimoto-Yasuda Makoto Ikenaga Susumu Asakawa Han-Yong Kim Masumi Okada Kazuhiko Kobayashi Makoto Kimura 《Soil Science and Plant Nutrition》2005,51(1):91-100
The effect of free-air CO2 enrichment (FACE) on the methanogenic archaeal communities inhabiting rice roots was studied in a Japanese rice field by separately collecting rice roots three times (at mid-tillering, panicle initiation, and heading stages) according to their nodal number, extracting DNA from the roots and subjecting it to polymerase-chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) and sequence analyses. Appearance of roots indicated that aging and senescence occurred faster under the FACE conditions than under the ambient conditions. The number of DGGE bands of methanogenic archaeal communities tended to increase with the growth stages. Cluster analysis showed that the succession of methanogenic archaeal communities in the ambient plot preceded that in the FACE plot, while the trend of the appearance of rice roots was opposite. All the closest relatives associated with the DGGE bands belonged to Methanomicrobiales and Rice cluster I, and FACE did not affect the phylogenetic position of the closest relatives associated with the characteristic DGGE bands. Faster succession of methanogenic archaeal communities in the ambient plot and similar phylogenetic members between the plots were observed in rice roots in years with both warmer (1999) and cooler (2003) weather during the rice cultivation period than in average years. 相似文献
338.
Studies of the constituents of Uruguayan propolis 总被引:4,自引:0,他引:4
Kumazawa S Hayashi K Kajiya K Ishii T Hamasaka T Nakayama T 《Journal of agricultural and food chemistry》2002,50(17):4777-4782
Eighteen flavonoids including two new compounds, four aromatic carboxylic acids, and eleven phenolic acid esters including one new compound were isolated and identified from the ethyl acetate soluble fraction of the 70% ethanol extract of Uruguayan propolis. The new compounds were elucidated as pinobanksin 3-(2-methyl)butyrate (1; recently reported in Usia, T.; Banskota, A. H.; Tezuka, Y.; Midorikawa, K.; Matsushige, K.; Kadota, S. J. Nat. Prod. 2002, 65, 673-676) pinobanksin 3-isobutyrate (2), and 2-methyl-2-butenyl ferulate (24). The constituents isolated from Uruguayan propolis in this study were similar to those of propolis of European and Chinese origin. Thus, it is suggested that the Uruguayan propolis has a plant origin similar to those of propolis from Europe and China. 相似文献
339.
This study examined the extent of damage by monofilament fishing lines on the cauliflower coral (Pocillopora meandrina) colonies at a popular cast fishing site in Oahu, Hawaii in March 1998. Sixty-five percent of coral colonies had fishing lines on their surface, and 80% of colonies were either entirely or partially dead. The percentage of entirely and partially dead colonies was positively correlated with the percentage of colonies entangled with fishing lines. Percent dead coral surface area was larger for colonies with fishing lines than colonies without fishing lines. In colonies with fishing lines, percent dead coral surface area was positively correlated with percent area with fishing lines. The high incidence of coral colonies with fishing lines and the three sets of significant results indicated destructive effects of monofilament fishing lines to P. meandrina corals. There is thus a clear case that reefs should be protected not only from the effects of excessive removal of fishes, but also from the effects of unsuccessful fishing that results in fishing-line entanglement on corals. 相似文献
340.