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排序方式: 共有195条查询结果,搜索用时 15 毫秒
1.
ABSTRACT: An application of the acoustic Doppler current profiler (ADCP, 153.6 kHz) in combination with a scientific echo sounder (EK60, 38 and 200 kHz) was investigated to estimate the density of krill Euphausia pacifica . The acoustic backscattering strength from sound scattering layers was compared with biomass estimates from midwater trawls. Euphausia pacifica was targeted among mixed species populations in the sound scattering layer in the offshore Funka Bay area of Hokkaido, Japan. The frequency characteristics of acoustic backscattering by krill were calculated using a distorted wave Born approximation scattering model at three frequencies. Krill aggregations identified from the EK60 data were extracted as the mean volume backscattering strength difference between two frequencies. They were then used to identify similar aggregations in the ADCP data by matching observation times and depths for the two methods, which were applied simultaneously. Results from the comparison of the mean volume backscattering strength and the density calculated from the ADCP and EK60 showed that ADCP can be used to measure density and spatial–temporal distribution of krill aggregations. Current speed and direction at the study site were found to be 16.1 cm/s and 187.0°, respectively, and krill speed and direction (including the current component) were found to be 19.8 cm/s and 172.2°, respectively. Based on the ADCP data, the net speed and direction of the krill aggregations were found to be 5.9 cm/s and 128.0°, respectively. 相似文献
2.
Competitive enzyme-linked immunosorbent assay for the detection of the antibodies specific to akabane virus. 总被引:5,自引:0,他引:5
Tomoyuki Tsuda Kazuo Yoshida Tohru Yanase Seiichi Ohashi Makoto Yamakawa 《Journal of veterinary diagnostic investigation》2004,16(6):571-576
A competitive enzyme-linked immunosorbent assay (C-ELISA) using neutralizing monoclonal antibodies (MAbs) against Akabane virus (AKAV) was developed to detect antibodies to AKAV in cattle sera. The performance of the test using 7 different competitor MAbs was evaluated in sequential serum samples and sera from cattle infected with various bovine arboviruses. The dynamics of the antibody response expressed by percentage of inhibition (PI) in C-ELISA coincided with those of neutralizing antibody titers in sequential serum samples from 2 cattle experimentally infected with AKAV. The value of PI in C-ELISA for convalescent sera from cattle infected with arboviruses correlated with the neutralizing antibody titer to AKAV but was unaffected by the antibodies to other arboviruses. In the validation experiment of C-ELISA using 286 bovine sera previously examined for the AKAV antibody by serum neutralization (SN) test, the relative specificity of C-ELISA was more than 98%, whereas the relative sensitivities of individual MAbs ranged from 49% to 82.2%. Overall agreement between C-ELISA and the SN test varied from 72% to 90% depending on the MAb. These results suggest that the C-ELISA is acceptable as a rapid and specific method for detecting antibodies to AKAV and is a potential alternative to the SN test. 相似文献
3.
4.
Twenty plant materials collected from the islands of Java and Kalimantan in Indonesia were extracted with 50% aqueous ethanol
(crude extract). The crude extracts were assayed for antimicrobial activities against Streptococcus sobrinus and for glucosyltransferase (GTase) inhibition. Fourteen extracts inhibited the growth of S. sobrinus by more than 50% and six extracts inhibited GTase activity by more than 50% at a concentration of 100 μg/ml. Koompassia malaccensis (kempas) extracts showed 90% depression of S. sobrinus growth and 80% inhibition of GTase activity at a concentration of 100 μg/ml. Kempas crude extracts were subjected to column
chromatography using Sephadex LH-20 and then preparative high-performance liquid chromatography to isolate four compounds
A, B, C, and D. These compounds were identified as taxifolin and the flavanonol rhamnoside isomers neoastilbin, astilbin,
and isoastilbin, respectively, from 1H and 13C nuclear magnetic resonance (NMR) spectra and other two-dimensional NMR techniques (COSY, HMBC, and HMQC). Each compound
depressed the growth of S. sobrinus over a concentration range of 9.3242.7 μg/ml and showed GTase inhibitory activity with IC50 values in the range 27.4–57.3 μg/ml. Taxifolin and flavanonol rhamnoside isomers isolated for the first time from kempas
could be potent compounds for preventing dental caries.
Part of this report was presented at the 57th Annual Meeting of the Japan Wood Research Society Conference, Hiroshima, 2007 相似文献
5.
Yasuhiro Tomitaka Tohru Yamashita Kazusato Ohshima 《Journal of General Plant Pathology》2007,73(3):197-208
The genetic structure of the populations of Turnip mosaic virus in Kyushu and central Honshu, Japan was assessed. The host specificity of isolates was determined, and their gene sequences
compared utilizing a population genetic approach. Phylogenetic analysis of partial sequences revealed that 32 of 49 Honshu
isolates (65%) collected during 1997–2001 belonged to the basal-BR group as did 23 of 64 isolates from Kyushu. All these basal-BR
isolates infected both Brassica and Raphanus plants. However, analyses of the positions of recombination sites in five regions of the genome (one third of the full sequence)
showed that at least four intra-lineage recombinants were present in these populations. These analyses showed that Kyushu
and Honshu shared none of these subpopulations, and genetically distinct basal-BR populations were present in the two districts.
We conclude that different basal-BR subpopulations had expanded into those districts.
The nucleotide sequences are deposited in the DDBJ/EMBL/GenBank databases under accession numbers AB267281-AB267376. 相似文献
6.
7.
Keitaro Yamanouchi Katsuyuki Nakamura Shiho Takeuchi Tohru Hosoyama Takashi Matsuwaki Masugi Nishihara 《Animal Science Journal》2021,92(1):e13573
The degree of intramuscular adipose tissue accumulation is one of the factors affecting meat quality. Accumulation of adipocytes is also observed under the pathological condition of skeletal muscle such as muscular dystrophy and sarcopenia. The origin of adipocytes seen in skeletal muscle is mesenchymal progenitor cells that can give rise to both adipocytes and fibroblasts. In the present study, we demonstrated that siRNA-mediated suppression of MyoD expression in rat skeletal muscle progenitor cell culture, which comprises both myogenic satellite cells and mesenchymal progenitor cells, resulted in diminished myotube formation and an unexpected spontaneous appearance of white adipocytes. Suppressing myomaker expression also resulted in complete absence of myotube formation without reducing MyoD expression, but no adipogenesis was seen in this scenario, indicating that decline in MyoD expression rather than decreased myotube formation is necessary to induce adipogenesis. In addition, spontaneous adipogenesis induced by suppressing MyoD expression in culture was inhibited by the conditioned medium from control culture, indicating that anti-adipogenic factor(s) are secreted from MyoD-positive myogenic cells. These results indicate the presence of regulatory mechanism on adipogenesis by myogenic cells. 相似文献
8.
Tohru Watanabe Kohzy Hiramatsu Yasushige Ohmori Young-Ki Paik 《Anatomia, histologia, embryologia》1990,19(3):245-254
The distribution patterns of acetylcholine esterase positive nerve fibers in the goat adrenal gland is described. Some positive cells are observed within the capsule. Terminals were identified in both the medulla and the cortex of the gland. 相似文献
9.
Due to a processing error, first author's name is missing in the HTML version of this article abstract page. The correct authors
are given below:
Jun Mu, Tohru Uehara, Takeshi Furuno
The online version of the original article can be found at 相似文献
10.
Yasutaka Watanabe Rie Mihara Tohru Mitsunaga Tsuyoshi Yoshimura 《Journal of Wood Science》2005,51(5):514-519
Fractions of methanol and ethanol extracts from the heartwood of white cypress pine (Callitris glaucophylla Thompson et Johnson) were investigated for their repellent activity against subterranean termite Coptotermes formosanus Shiraki worker using a two-choice semicircular filter paper test at 0.5% (w/w) concentration. Fraction CY-E2 composed of
(−)-citronellic acid, guaiol, α-, β-, and γ-eudesmol isomers as well as an unknown compound, showed the highest statistically significant repellency (97.8% ± 2.2 SEM)
of all fractions tested. Bioactivity-guided fractionations using high-performance liquid chromatography led to the isolation
of two, oxygenated eudesmane-type sesquiterpenes with α-methylene moieties, both termite-repellent compounds. These compounds were subsequently identified as ilicic acid methyl
ester (IAME) and costic acid by means of spectroscopic analyses, electron impact mass spectrometry, and nuclear magnetic resonance
spectroscopy. We report the isolation of both IAME and costic acid from C. glaucophylla heartwood for the first time.
Part of this paper was presented at the 47th Symposium on the Chemistry of Terpenes, Essential Oils, and Aromatics, Tokyo,
November 2003 相似文献