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91.
Takahashi Y Konishi H Sato K Oohashi T Miyamoto T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(10):1199-1204
The present report describes an enzyme-linked immunosorbent assay for bovine apolipoprotein (apo) A-IV. This assay was applied to the determination of its concentration and distribution in sera from cattle. The distribution of apoA-IV in lipoprotein fractions separated by ultracentrifugation was mostly recovered in the non-lipoprotein fractions (d>1.21 g/ml, 90%), but, in the case of gel filtration chromatography, apoA-IV was mainly eluted in HDL and non-lipoprotein fractions. The apoA-IV concentrations during early, mid- and late lactating stages in cows were significantly higher than during the nonlactating stage (p<0.05). From early to late lactating stages, the concentration of apoA-IV was unaltered. After 4 days of fasting, the concentration of plasma apoA-IV had decreased significantly (p<0.05) at days 3 and 4, and was returned to the basal level by 3 days of refeeding. These results suggested that the concentration of apoA-IV is modified by nutritional conditions. 相似文献
92.
Shun TAKEO Daichi SATO Koji KIMURA Yasunori MONJI Takehito KUWAYAMA Ryoka KAWAHARA-MIKI Hisataka IWATA 《The Journal of reproduction and development》2014,60(2):92-99
The aim of the present study was to address the effect of resveratrol-mediated
upregulation of sirtuin 1 (SIRT1) during oocyte maturation on mitochondrial function, the
developmental ability of oocytes and on mechanisms responsible for blockage of polyspermic
fertilization. Oocytes collected from slaughterhouse-derived ovaries were cultured in
TCM-199 medium supplemented with 10% FCS and 0 or 20 µM resveratrol (Res). We examined the
effect of Res on SIRT1 expression in in vitro-matured oocytes (Exp 1);
fertilization and developmental ability (Exp 2); mitochondrial DNA copy number (Mt
number), ATP content and mitochondrial membrane potential in matured oocytes (Exp 3); and
the time required for proteinase to dissolve the zona pellucida following in
vitro fertilization (as a marker of zona pellucida hardening), as well as on
the distribution of cortical granules before and after fertilization (Exp 4). In Exp 1,
the 20 µM Res treatment upregulated protein expression of SIRT1 in oocytes. In Exp 2, Res
treatment improved the ratio of normal fertilization and the total cell number of
blastocysts. In Exp 3, Res treatment significantly increased the ATP content in matured
oocytes. Additionally, Res increased the overall Mt number and mitochondrial membrane
potential, but the effect was donor-dependent. In Exp 4, Res-induced zona hardening
improved the distribution and exocytosis of cortical granules after in
vitro fertilization. In conclusion, Res improved the quality of oocytes by
improving mitochondrial quantity and quality. In addition, Res added to the maturation
medium enhanced SIRT1 protein expression in oocytes and improved fertilization via
reinforcement of the mechanisms responsible for blockage of polyspermic fertilization. 相似文献
93.
Nakamura T Noguchi T Tanaka M Zolensky ME Kimura M Tsuchiyama A Nakato A Ogami T Ishida H Uesugi M Yada T Shirai K Fujimura A Okazaki R Sandford SA Ishibashi Y Abe M Okada T Ueno M Mukai T Yoshikawa M Kawaguchi J 《Science (New York, N.Y.)》2011,333(6046):1113-1116
The Hayabusa spacecraft successfully recovered dust particles from the surface of near-Earth asteroid 25143 Itokawa. Synchrotron-radiation x-ray diffraction and transmission and scanning electron microscope analyses indicate that the mineralogy and mineral chemistry of the Itokawa dust particles are identical to those of thermally metamorphosed LL chondrites, consistent with spectroscopic observations made from Earth and by the Hayabusa spacecraft. Our results directly demonstrate that ordinary chondrites, the most abundant meteorites found on Earth, come from S-type asteroids. Mineral chemistry indicates that the majority of regolith surface particles suffered long-term thermal annealing and subsequent impact shock, suggesting that Itokawa is an asteroid made of reassembled pieces of the interior portions of a once larger asteroid. 相似文献
94.
Summary To determine the origin of Ogura male sterile cytoplasm in radish (Raphanus sativus L.), wild and cultivated radishes were crossed. Three types of progeny resulted from the F1 hybrids between the wild radish from Kushikino with Ogura-type mtDNA and the cultivars (Uchiki-Gensuke or Comet). The segregation patterns of the male sterility were compared with those of Ogura cytoplasm. The male sterility induced in the F1 hybrid was maintained by crossing with Uchiki-Gensuke, that maintains Ogura male sterility. In the two types of progeny, in which Comet (a restorer of Ogura cytoplasm) was used as one of the parents, both fertile and sterile plants segregated at the predicted ratio on the assumption that a single dominant fertility restoring gene exists in the restorer. From these results, we concluded that the Ogura cytoplasm is identical to that of the wild radish, and the former originated in a population of Japanese wild radish. 相似文献
95.
96.
97.
ABSTRACT: Elongate ilisha Ilisha elongata is a commercially important fishery resource in both Japan and China. Age and growth of the species were investigated by scale analysis from June 1996 to July 1997 in Ariake Sound, Japan. Scale annuli were formed once a year mainly between June and July. The age was 1–6 years for both male and female individuals. There was no significant difference in the regression of fork length (FL) on scale radius ( R ) between sexes by a covariance analysis. The combined sex von Bertalanffy growth equations were expressed as L t = 495.4 × (1 − e−0.3176( t + 0.4108) ), where L t is FL in mm at age t . Comparison of the age and growth among different populations from coastal waters in the western North Pacific Ocean suggested that the FL of the Ariake population is the smallest at each age. The spatio–temporal variations in growth are possibly relevant to environmental conditions of the growth grounds of subadults; however, there was no gradient change in the growth of I. elongata with latitude. Water temperature may not be the main factor affecting the growth of this species . The growth of the tropical population from Sarawak differs greatly from those of temperate and subtemperate populations, which implies genetic variation or phenotypic plasticity in different climate zones. 相似文献
98.
Yuichiro Hiraoka Noritsugu Kuramoto Mineko Ohira Masanori Okamura Toru Taniguchi Yoshitake Fujisawa 《Journal of Forest Research》2011,16(6):509-517
Rhus succedanea L. is cultivated in Japan for the wax that can be extracted from its fruits. We determined genetic data for specific traits
associated with wax production (fruit number per cluster, FN, fruit weight, FW, number of clusters per area, CN, and wax content,
WC) in five traditional cultivars and 13 newer clones. Data were collected over 4 years and alternate bearing was observed:
2001 and 2003 were years with high yields; in 2002 and 2004 yields were poor. The restricted maximum likelihood method was
used to calculate (co)variance components for analysis. Broad sense heritability was estimated and ranged from low (FN and
CN) to high (FW and WC) for the traits examined. There were positive genetic correlations between FW and WC and negative ones
between FN and FW throughout the 4 years. Genetic correlations between CN and the other traits were positive in good crop
years and negative in bad crop years. For each assessed clone, the four traits in the 4 years were evaluated using best linear
unbiased predictors (BLUP) of the clonal breeding values. The BLUP scores for both FW and WC exhibited positive correlations
between pairs of years, whereas there were positive BLUP correlations for CN when the high yield and low yield years were
examined separately. The traditional cultivars and the newer clones were also characterized. Some of the clones were better
than the traditional cultivars with regard to wax yield and reliability of production. The trait characteristics and the future
breeding are discussed. 相似文献
99.
In 2009, chlorotic mottle and necrosis were observed on chrysanthemums (cv. Jimba) in Aomori Prefecture, Japan. A virus was
isolated from the chrysanthemum plants by serial local-lesion transfer. The symptoms exhibited by the test plants, the particle
morphology, the features of the protein and the potential for transmission by thrips were similar to those for Impatiens necrotic spot virus (INSV). The partial nucleotide sequences of the nucleocapsid protein gene and the 3′-untranslated sequence of the S RNA shared
99% identity with that of an INSV isolate. This report is the first of INSV infection of chrysanthemums in Japan. 相似文献
100.
Toru TSUCHIDA Yoshihiko TAKAHASHI Norikuni OHTAKE Takuji OHYAMA Masaru KUBOTA 《Soil Science and Plant Nutrition》2006,52(1):133-133
(pp. 811–816)
The application method of liquid fertilizer with irrigation water was tested in large scale paddy fields using a newly developed fertilizer supplier which can make a supplying rate of liquid fertilizer constant. Uniformity of fertilization, change in the nitrogen concentration of flooded water and absorption of applied nitrogen by paddy rice were examined. High uniformity of fertilization was achieved with this method as compared with a conventional broadcast application of granular fertilizer, or an inflow fertilization of granule-like fertilizer with irrigation water.
When urea was applied as liquid fertilizer, the fertilizer-N disappeared quickly from ponding water under shallow conditions of ponding water depth. In the case of the same depth of ponding water, the rate of reduction was large under conditions of large permeability of water.
The nitrogen utilization rates of urea and ammonium sulfate labeled with15 N were not related to the depth of ponding water at the time of fertilization. When ammonium sulfate was supplied the nitrogen utilization rate was around 50% regardless of fertilization conditions however, the urea-N utilization rate fell to 40% or less at a permeability of ponding water of 0.8 cm day−1 or less, while it increased to 50% equivalent to ammonium sulfate, at 0.8 cm day−1 or more permeability. 相似文献
The application method of liquid fertilizer with irrigation water was tested in large scale paddy fields using a newly developed fertilizer supplier which can make a supplying rate of liquid fertilizer constant. Uniformity of fertilization, change in the nitrogen concentration of flooded water and absorption of applied nitrogen by paddy rice were examined. High uniformity of fertilization was achieved with this method as compared with a conventional broadcast application of granular fertilizer, or an inflow fertilization of granule-like fertilizer with irrigation water.
When urea was applied as liquid fertilizer, the fertilizer-N disappeared quickly from ponding water under shallow conditions of ponding water depth. In the case of the same depth of ponding water, the rate of reduction was large under conditions of large permeability of water.
The nitrogen utilization rates of urea and ammonium sulfate labeled with