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141.
Kaoru NISHINE Hiroshi AOKI Yoshihiro SAKODA Akio FUKUSHO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2014,76(12):1635-1639
Field isolates of BVDV which do not show the exaltation of Newcastle disease virus (END)
phenomenon (END–) are rarely reported. In this study, 45 BVDV field isolates
from cattle in Hokkaido prefecture in Japan were analyzed by the reverse plaque formation
method, the END method and observation of cytopathic effects. END– virus was
detected in 34 of 45 isolates (75.6%), although 35 of 45 field isolates contained END
phenomenon positive virus as the predominant virus population. We propose that
END– viruses are widely distributed in the field and that it is possible that
the mixture of biologically distinct BVDV correlates with the appearance of disease in
infected animals. 相似文献
142.
Ishii N Nakahigashi K Baba T Robert M Soga T Kanai A Hirasawa T Naba M Hirai K Hoque A Ho PY Kakazu Y Sugawara K Igarashi S Harada S Masuda T Sugiyama N Togashi T Hasegawa M Takai Y Yugi K Arakawa K Iwata N Toya Y Nakayama Y Nishioka T Shimizu K Mori H Tomita M 《Science (New York, N.Y.)》2007,316(5824):593-597
Analysis of cellular components at multiple levels of biological information can provide valuable functional insights. We performed multiple high-throughput measurements to study the response of Escherichia coli cells to genetic and environmental perturbations. Analysis of metabolic enzyme gene disruptants revealed unexpectedly small changes in messenger RNA and proteins for most disruptants. Overall, metabolite levels were also stable, reflecting the rerouting of fluxes in the metabolic network. In contrast, E. coli actively regulated enzyme levels to maintain a stable metabolic state in response to changes in growth rate. E. coli thus seems to use complementary strategies that result in a metabolic network robust against perturbations. 相似文献
143.
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
144.
Kazuyuki Inubushi Miwa Yashima Shunsuke Hanazawa Akio Goto Kisho Miyamoto Tatsushi Tsuboi 《Soil Science and Plant Nutrition》2020,66(1):247-253
ABSTRACT This study aims to characterize soil chemical properties and microbial biomass, greenhouse gas production, and organic matter dynamics in upland rice field as affected by the long-term fertilizer managements in Uganda. Soil total C (TC) and N (TN) contents were in the relatively smaller range under different fertilizer treatments, even after 20 crop seasons. However, available phosphate contents showed positive correlation with average yield of upland rice. Incubation experiments were conducted under aerobic or under flooding conditions to measure CO2, methane, and nitrous oxide productions. After the incubation, soil samples were extracted to quantify nitrification rate for aerobic condition and ammonification rate for flooding condition. Soil microbial biomass carbon (MBC) and nitrogen were measured. Stable isotope ratio of 13C and 15N were also determined for the soil samples. CO2 production potential under aerobic condition was higher than the flooding condition. The qCO2 (CO2/MBC) in the treatment applied with compost tended to be higher than the other treatments. Positive correlation between nitrous oxide production and nitrification was found. The delta 13C values of the soil samples indicated that the effect of C4 plants before rice cultivation still remained, while the contribution of biological N2 fixation was little according to delta 15N values. These results indicate that soil microbial biomass in upland rice field of the long-term fertilizer experiment in Uganda was characterized with higher qCO2. Greenhouse gas production was affected by fertilizer management, while soil organic C before the long-term experiment still remained in the experiment. 相似文献
145.
We derive a two-way volume equation for estimating the apparent culm volume of one of the largest bamboo species, Phyllostachys pubescens Mazel ex Houz. The volume equation was derived from the assumptions that (1) the relative culm form can be expressed by Kunze’s
equation and (2) normal form-factors at two different relative heights are steady at constants independent of culm sizes.
A total number of 200 sample culms were collected from a stand of P. pubescens in Mt. Toshima, Kumamoto Prefecture, western Japan, and were randomly bisected into two sets of data, i.e. modeling and test
data. For the modeling data, normal form-factors at 0.6 and 0.9 in relative height were steady at 0.908 and 0.448, respectively.
The coefficients of the volume equation were determined based on these steady values of the normal form-factors. For the test
data, the apparent culm volume was estimated from diameter at breast height and culm height with the determined volume equation.
The mean error and root mean square error of the estimated culm volume were, respectively, 8.120 × 10−5 and 3.291 × 10−3 m3, and there was no significant difference between estimated and actual volume. In conclusion, the two-way volume equation
presented here appears to be convenient for predicting the apparent culm volume for P. pubescens. 相似文献
146.
Shin Kato Kenichiro Fujii Setsuzo Yumoto Masao Ishimoto Tatsuhiko Shiraiwa Takashi Sayama Akio Kikuchi Takeshi Nishio 《Breeding Science》2015,65(2):154-160
The present study was conducted to evaluate the benefits of indeterminate growth habit in breeding to improve yield potential of Japanese soybean varieties, which exclusively have determinate growth habit. Two populations of recombinant inbred lines (RILs) derived from crosses between determinate Japanese cultivars and indeterminate US cultivars were grown in Akita and Kyoto, and seed weight per plant (SW) and its components were compared between indeterminate and determinate RILs. The difference of SW between the two growth habits in RILs varied depending on maturation time. The SW of early indeterminate lines was significantly higher than that of early determinate ones in Akita, but not in Kyoto. Among yield components, the number of seeds per pod was constantly larger in indeterminate lines than that in determinate ones irrespective of maturation time. The number of seeds per plant and the number of pods per plant of the indeterminate lines were greater than those of the determinate lines in early maturation in Akita. These results suggest that the indeterminate growth habit is an advantageous characteristic in breeding for high yield of early maturing soybean varieties in the Tohoku region. 相似文献
147.
Expression of mRNA for the angiopoietin-tie system in granulosa cells during follicular development in cows 总被引:2,自引:0,他引:2
Hayashi KG Berisha B Matsui M Schams D Miyamoto A 《The Journal of reproduction and development》2004,50(4):477-480
Recent findings indicate that the changing profile of angiopoietins (ANPT) and their receptor Tie2 are closely associated with development and regression of the vascular network in the cyclic ovary. We previously reported that mRNA expression for the ANPT-Tie system in theca interna changes during bovine follicular development and atresia, and both ANPTs affect steroidogenesis in the preovulatory follicle. The aim of this study was to investigate mRNA expression for ANPT1, ANPT-2 and Tie2 in granulosa cells (GC) during follicular development in the cow. Bovine follicles were classified according to the estradiol-17beta (E(2)) concentration in follicular fluid (FF) as follows: (1) E(2)<0.5, (2) 0.5180 ng/ml FF. Semi-quantitative RT-PCR analysis revealed that the expression of ANPT-1 mRNA was not detected in most of the follicle with E(2)<5 ng/ml (diameter of 5-10 mm), but clearly detected in all follicles with E(2)>5 ng/ml (diameter of >10 mm). The mRNA expression for ANPT-2 was drastically decreased in the follicles with E(2)>5 ng/ml. Tie2 mRNA expression remained unchanged at the different stages of follicular development. The present data show that ANPT-1 becomes predominant in the follicle producing high levels of E(2), indicating the possible switch-over from ANPT-2 (antagonist) to ANPT-1 (agonist). Thus, the result suggests that the ANPT-Tie system in bovine GC may stimulate E(2) secretion rather than angiogenesis in the late stages of follicular development. 相似文献
148.
149.
Mutsumi NAKAMURA Takafumi NAGAMINE Akio TAKENAKA Rustem I. AMINOV Koretsugu OGATA Kiyoshi TAJIMA Hiroki MATSUI Yoshimi BENNO Hisao ITABASHI 《Animal Science Journal》2002,73(5):347-352
A 2.6-kb DNA fragment encoding a xylanase gene ( xyn A) was cloned from the rumen hemicellulolytic bacterium Ruminococcus albus 7. The deduced primary structure of the protein (XynA) was divided into a signal peptide region and 3 domains. Domain A was identified as a family 11 (G) catalytic domain, but one amino acid residue was replaced by another in an active site signature 1 of family 11. Domain B is a stabilizing domain for the catalytic domains of families 10 and 11. Deletion of domain B reduced stability of the xylanase at high temperature and at high and low pH. Domain B may be useful for protein engineering of xylanase. Domain C has sequence similarity to deacetylases and NodB proteins. 相似文献
150.