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51.
Subedi R Shneor R Monaghan P Anderson BD Aniol K Annand J Arrington J Benaoum H Benmokhtar F Boeglin W Chen JP Choi S Cisbani E Craver B Frullani S Garibaldi F Gilad S Gilman R Glamazdin O Hansen JO Higinbotham DW Holmstrom T Ibrahim H Igarashi R de Jager CW Jans E Jiang X Kaufman LJ Kelleher A Kolarkar A Kumbartzki G Lerose JJ Lindgren R Liyanage N Margaziotis DJ Markowitz P Marrone S Mazouz M Meekins D Michaels R Moffit B Perdrisat CF Piasetzky E Potokar M Punjabi V Qiang Y Reinhold J Ron G 《Science (New York, N.Y.)》2008,320(5882):1476-1478
The protons and neutrons in a nucleus can form strongly correlated nucleon pairs. Scattering experiments, in which a proton is knocked out of the nucleus with high-momentum transfer and high missing momentum, show that in carbon-12 the neutron-proton pairs are nearly 20 times as prevalent as proton-proton pairs and, by inference, neutron-neutron pairs. This difference between the types of pairs is due to the nature of the strong force and has implications for understanding cold dense nuclear systems such as neutron stars. 相似文献
52.
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
53.
Hiromichi Ohtsuka Hiroki Kobayashi Kumi Kinouchi Miki Kiyono Yousuke Maeda 《Animal Science Journal》2014,85(5):575-580
Japanese Black (JB) calves are more susceptible to infectious diseases compared to Holstein (Hol) calves. To clarify the immunological differences between JB and Hol calves, expression of cytokine messenger RNA (mRNA) was examined using peripheral CD4+, CD8+ and γδ T cells. Healthy calves, 24 from each species, were examined. Blood samples were obtained from calves at 1 week, 1 month and 3 months old, eight calves for each age of each species. Peripheral blood mononuclear cells were stimulated with phytohemagglutin (PHA), and T cell subsets were isolated by positive selection using magnetic cell sorting (MACS). Levels of interlekin (IL)‐2, IL‐4, IL‐10 and interferon (IFN)‐γ mRNA in three T cell subsets were analyzed. WC1‐N1+ γδ T cell percentages were significantly lower in JB calves at 1 week and 1 month of age compared to Hol calves. In addition JB calves had significantly lower IL‐2, IL‐10 and IFN‐γ mRNA in WC1‐N1+ γδ T cells at 1 and 3 months of age, whereas there were no significant differences in cytokine mRNA of CD4+ and CD8+ cells between the two groups. Decreased cytokine mRNA and cell number of peripheral γδ T cells may affect negatively on the immune system of JB calves. 相似文献
54.
Aiko Nakano Hidetoshi Ikeno Toshifumi Kimura Hiromichi Sakamoto Masako Dannoura Yasuhiro Hirano Naoki Makita Leena Finér Mizue Ohashi 《植物养料与土壤学杂志》2012,175(5):775-783
Information related to the growth of fine roots is important for understanding C allocation in trees and the mechanisms of C cycling in ecosystems. Observations using a camera or scanner embedded in the soil enabled us to obtain continuous images of fine‐root‐growth dynamics. However, these methods are still labor‐intensive because the image analysis has to be conducted manually. We developed an automated method for tracking movement or elongation of fine roots using a sequence of scanner images. We also show how data obtained with these methods can be used for calculating fine‐root behavior. Two A4‐size scanners were buried in a mixed forest in Japan and images were taken continuously from within the soil. We preprocessed these images by extracting the fine‐root area from the images and developed an automated calculation plug‐in we named A‐root for tracking growth movement of the tips of fine roots. A‐root and manual‐tracking results were compared using the same images. The results show the A‐root and manual‐tracking methods yielded similar levels of accuracy. The average growth rate of 17 fine roots tracked using the program was 0.16 mm h–1. The observation of the direction of growth in fine roots showed the direction may be influenced by the original root's growth where the fine roots branched, distribution of soil particles, other roots, and the force of gravity. The A‐root analysis also suggested there may be an interaction between speed of growth and changes in direction of growing fine roots. 相似文献
55.
Hiromichi MITAKE Naoto ITO Kota OKADERA Kazuma OKADA Kento NAKAGAWA Tomomi TANAKA Kiyohito KATSURAGI Kasumi KASAHARA Toshihide NIHONGI Hiroshi TSUNEMITSU Makoto SUGIYAMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(2):221-224
A total of 568 normal feces from calves on a beef farm in Fukui Prefecture, Japan, in 2011–2012 were examined by RT-semi-nested PCR for rotavirus A (RVA) VP4 genes. Through partial sequencing and BLAST analyses of 84 VP4-positive specimens, we identified an avian-like RVA strain, N2342, which shares highest nucleotide identity (80.0%) with known avian-like bovine strain 993/83, in one specimen. Phylogenetic analysis also revealed a close genetic relationship between N2342 and avian RVAs, suggesting bird-to-cattle transmission. We observed frequent contact of wild birds with calves in the farm, suggesting that these birds were the source of the virus. 相似文献
56.
57.
K Miyahara S Tose H Sakurai I Igarashi A Saito T Hirose N Suzuki 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(4):629-635
In order to identify mechanisms responsible for the anti-tumor effects of Toxoplasma lysate antigen (TLA), we used an in vitro 51Cr release assay to study the functional properties of plastic-adherent cells during induction of splenic cytotoxic activity by TLA. Cytotoxic activity of non-adherent cells was measured in all experiments after a 6 days incubation. Induction of cytotoxic non-adherent cells by TLA required the presence of plastic-adherent spleen cells. In contrast, rhIL-2 alone was able to induce transformation of cytotoxic non-adherent cells from non-adherent spleen cells. Contact between adherent and non-adherent spleen cells was necessary for successful induction of cytotoxic non-adherent cells by TLA. Treatment of spleen cells with anti-macrophage serum prevented induction of cytotoxic activity by TLA. Biologically active IL-2 was not detected in culture supernatants of spleen cells exposed to TLA. These findings suggest that contact between TLA-sensitized non-adherent cells and macrophages is necessary for induction of cytotoxic cells in the presence of TLA. This contact, however, is not necessary for generation of IL-2-induced killer cells. 相似文献
58.
59.
H Sakurai Y Fujii Y Maki I Igarashi Y Omata A Saito K Ono N Suzuki 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1991,53(5):823-831
Novel synthetic Obiopeptide (Obi-1), Glycil-penta-Glutamate, as an immunoregulator, injected intramuscularly to methylcholanthrene (MC) induced tumour bearing mice at 30-100 micrograms per mouse weekly, significantly inhibited tumour growth, compared to that of the untreated control. Numbers of mononuclear cells (MNC) in the spleen obtained from Obi-1 treated and untreated mice were reduced to 64% and 10% of the normal levels, respectively. In histopathological findings, variations of MNC in the spleen was observed in colonies of large MNC and lymphocytes in Obi-1 treated red marrow, while untreated one showed only scattered number of small lymphocytes. A significant O2- production was noted in monolayers of normal macrophages incubated with 0.5 mg Obi-1/ml for 48 hr. Cytotoxicity of spleen MNC cultured with Obi-1 against MC-tumour, Meth A, P-815 and YAC-1 target cells showed less than 10% cytotoxic activity in almost all experiments. 相似文献