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551.
The influence of chloropolysporin-C, a new glycopeptide antibiotic, on in vitro activity of Clostridium perfringens isolates and its effects on the intestinal microflora of broiler chickens was examined. The in vitro sensitivity of 88 isolates of C perfringens to four antimicrobial agents, including chloropolysporin-C, was tested by an agar dilution method. The antibiotics used all had minimum inhibitory concentration levels of 6.25 micrograms ml-1 or less against this organism. Changes were examined in the intestinal microflora of broiler chickens fed a diet containing chloropolysporin-C to obtain basic data on the mechanisms by which the antibiotic aided livestock production. No clinical findings were recognised in chickens tested during the period of antibiotic administration. A decrease in viable cells of the clostridia was the principal response recognised during the period of drug administration in feed. Among the other microflora, chloropolysporin-C led to a significant response among Gram-positive bacteria, but no changes in the total bacterial count. 相似文献
552.
Toru Kondo Shin-ichi Fuji Kazuo Yamashita Dong-Kyoon Kang Moo-Ung Chang 《Journal of General Plant Pathology》2005,71(6):441-443
We identified Broad bean wilt virus 2 (BBWV-2) in yams based on particle morphology, test plant symptoms, protein features, aphid transmission, and molecular classification
using nucleotide sequences of coat protein genes. 相似文献
553.
Ali Akbar MASOUDI Kazuyuki UCHIDA Kou YOKOUCHI Keiko MIYADERA Hiroyuki OGAWA Yoshikazu SUGIMOTO Tetsuo KUNIEDA 《Animal Science Journal》2007,78(6):672-675
Forelimb‐girdle muscular anomaly is a hereditary disorder of Japanese Black cattle characterized by tremors and astasia caused by hypoplasia of the forelimb‐girdle muscles. The locus responsible for this disorder has been mapped on a middle region of bovine chromosome 26. In this study, we applied marker‐assisted selection to identify the carriers of this disorder. Four microsatellite markers, DIK4440, BM4505, MOK2602 and IDVGA‐59, linked to the disorder locus were genotyped in 37 unaffected offspring of a carrier sire. Transmission of the mutant or wild‐type allele of the disorder locus of the sire to the 37 offspring was determined by examining the haplotypes of these markers. The results showed that nine and 18 of the 37 animals possessed the paternally transmitted mutant and wild‐type alleles, respectively, and therefore, the nine animals with the mutant allele were identified as carriers. We concluded that the marker‐assisted selection using these four markers can be applied for the identification of the carriers of forelimb‐girdle muscular anomaly of Japanese Black cattle. 相似文献
554.
Cabbage (B. oleracea L. var. capitata L.) plants wore grown for 79 days in cuture solutions obtaining 4 levels of lithium, 0, 0.1, 1. 10 mel) sodium (0, 0.2. 2, 20, or rubidium , 0, 0.05, 0.5) combined with a low or high supply of potassium(0.2 or 2 mcf/l, and the effects of the cations supplied on the growth and ration composition of the plants were studied. The total dry weight of the plants decreased at higher levels of the cations, especially Li in the culture solution, concurrent with an increaie in the contents of each cation in the plants. The decrease in the dry weight at higher levels was smaller in the high K supply, than in the low supply, causing a decrease in the contents of the cations. The critical contents of Li, Na, and which resulted in a 50° decrease in the dry weight or inner leaves due to excess injury were estimated to be about 0.07, 2.5, and 3.0% on a dry basis in the outer leaves and 0.05, 2.0, and 3.0% in the roots, respectively, regardless of the K supply. 相似文献
555.
Takahiro Nishimaki Takayuki Ibi Yoshihiro Tanabe Yoshiyuki Miyazaki Naohiko Kobayashi Tamako Matsuhashi Takayuki Akiyama Emi Yoshida Kazumi Imai Mayu Matsui Keiichi Uemura Naoto Watanabe Tatsuo Fujita Yosuke Saito Tomohiko Komatsu Takahisa Yamada Hideyuki Mannen Shinji Sasazaki Tetsuo Kunieda 《Animal Science Journal》2013,84(8):585-591
Japanese Black cattle are at risk for genetic homogeneity due to intensive use of a few sires. Therefore, assessment of the actual genetic diversity of this breed is important for future breeding plans. In the present study, we investigated the genetic diversity within and among eight subpopulations of Japanese Black cattle using 52 microsatellite markers. The parameters for genetic diversity of Japanese Black cattle were comparable to those of other cattle breeds, suggesting that the relatively high genetic diversity of the breed. However, upon comparison among the eight subpopulations, the Hyogo subpopulation showed markedly low genetic diversity. The results of the pairwise FST values, phylogenetic network and structure analysis indicated that the Hyogo population has remarkably high level of genetic differentiation from other populations, while Yamagata, Niigata, Hiroshima and Kagawa populations have low levels of genetic differentiation. Furthermore, multidimensional scaling plots indicated that individuals in some subpopulations were separated from individuals in the other subpopulations. We conclude that while the overall genetic diversity of Japanese Black cattle is still maintained at a relatively high level, that of a particular subpopulation is significantly reduced, and therefore the effective population size of the breed needs to be controlled by correct mating strategies. 相似文献
556.
Kazuhito Ichii Masayuki Kondo Young-Hee Lee Shao-Qiang Wang Joon Kim Masahito Ueyama Hee-Jeong Lim Hao Shi Takashi Suzuki Akihiko Ito Hyojung Kwon Weimin Ju Mei Huang Takahiro Sasai Jun Asanuma Shijie Han Takashi Hirano Ryuichi Hirata Tomomichi Kato Sheng-Gong Li Ying-Nian Li Takahisa Maeda Akira Miyata Yojiro Matsuura Shohei Murayama Yuichiro Nakai Takeshi Ohta Taku M. Saitoh Nobuko Saigusa Kentaro Takagi Yan-Hong Tang Hui-Min Wang Gui-Rui Yu Yi-Ping Zhang Feng-Hua Zhao 《Journal of Forest Research》2013,18(1):13-20
Based on the model–data comparison at the eddy-covariance observation sites from CarboEastAsia datasets, we report the current status of the terrestrial carbon cycle modeling in monsoon Asia. In order to assess the modeling performance and discuss future requirements for both modeling and observation efforts in Asia, we ran eight terrestrial biosphere models at 24 sites from 1901 to 2010. By analyzing the modeled carbon fluxes against the CarboEastAsia datasets, the strengths and weaknesses of terrestrial biosphere modeling over Asia were evaluated. In terms of pattern and magnitude, the carbon fluxes (i.e., gross primary productivity, ecosystem respiration, and net ecosystem exchange) at the temperate and boreal forest sites were simulated best, whereas the simulation results from the tropical forest, cropland, and disturbed sites were poor. The multi-model ensemble mean values showed lower root mean square errors and higher correlations, suggesting that composition of multiple terrestrial biosphere models would be preferable for terrestrial carbon budget assessments in Asia. These results indicate that the current model-based estimation of terrestrial carbon budget has large uncertainties, and future research should further refine the models to permit re-evaluation of the terrestrial carbon budget. 相似文献
557.
Watson FL Püttmann-Holgado R Thomas F Lamar DL Hughes M Kondo M Rebel VI Schmucker D 《Science (New York, N.Y.)》2005,309(5742):1874-1878
558.
HIFalpha targeted for VHL-mediated destruction by proline hydroxylation: implications for O2 sensing 总被引:1,自引:0,他引:1
559.
During animal development, cells become progressively more restricted in the cell types to which they can give rise. In the central nervous system (CNS), for example, multipotential stem cells produce various kinds of specified precursors that divide a limited number of times before they terminally differentiate into either neurons or glial cells. We show here that certain extracellular signals can induce oligodendrocyte precursor cells to revert to multipotential neural stem cells, which can self-renew and give rise to neurons and astrocytes, as well as to oligodendrocytes. Thus, these precursor cells have greater developmental potential than previously thought. 相似文献
560.
Three-dimensional readout of flash x-ray images of living sperm in water by atomic-force microscopy 总被引:4,自引:0,他引:4
T Tomie H Shimizu T Majima M Yamada T Kanayama H Kondo M Yano M Ono 《Science (New York, N.Y.)》1991,252(5006):691-693
The imaging of living specimens in water by x-ray microscopy can be greatly enhanced with the use of an intense flash x-ray source and sophisticated technologies for reading x-ray images. A subnanosecond [corrected] x-ray pulse from a laser-produced plasma was used to record the x-ray image of living sea urchin sperm in an x-ray resist. The resist relief was visualized at high resolution by atomic-force microscopy. Internal structure of the sperm head was evident, and the carbon density in a flagellum was estimated from the relief height. 相似文献