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31.
Parasporal inclusion proteins produced by Bacillus thuringiensis strain A1470 exhibit strong cytotoxicity against human leukemic T cells when activated by protease treatment. One of the cytotoxic proteins was separated by anion exchange chromatography and gel filtration chromatography and designated Cry45Aa. Its gene was then expressed in recombinant Escherichia coli, in which the Cry45Aa precursor was accumulated in an inclusion body. It was solubilized in sodium carbonate buffer and processed with proteinase K, and cytotoxic activities of the protein against various mammalian cell lines were evaluated using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide assay. The protein exhibited high cytotoxic activity against CACO-2, Sawano, MOLT-4, TCS, and HL60 cells and moderate activity against U-937 DE-4, PC12, and HepG2 cells. On the other hand, the EC50 values against Jurkat, K562, HeLa, A549, Vero, COS-7, NIH3T3, CHO, and four normal tissue cells (human primary hepatocyte cells, UtSMC, MRC-5, and normal T cells) were >2 microg/mL.  相似文献   
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Displacement above the hypocenter of the 2011 Tohoku-Oki earthquake   总被引:3,自引:0,他引:3  
The moment magnitude (M(w)) = 9.0 2011 Tohoku-Oki mega-thrust earthquake occurred off the coast of northeastern Japan. Combining Global Positioning System (GPS) and acoustic data, we detected very large sea-floor movements associated with this event directly above the focal region. An area with more than 20 meters of horizontal displacement, that is, four times larger than those detected on land, stretches several tens of kilometers long along the trench; the largest amount reaches about 24 meters toward east-southeast just above the hypocenter. Furthermore, nearly 3 meters of vertical uplift occurred, contrary to observed terrestrial subsidence.  相似文献   
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Magnetic measurements have shown that nondiamagnetic minerals in a lunar crystalline rock of type B are (free Fe(2)+ in paramagnetic pyroxenes) : (antiferromagnetic FeSiO(3)) : (antiferromagnetic FeTiO(3)) : (ferromagnetic iron) = 4.3 : 7 : 20 : 0.08 in weight percentage. The abundance of ferromagnetic Fe in the lunar fines is about 7.5 times its abundance in the crystalline rock. The natural remanent magnetization of the crystalline rock of 7.5 x 10(-6) emu/ g in intensity may not be attributable to its thermoremanent magnetization.  相似文献   
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ABSTRACT

Cadmium (Cd) has an important impact on agriculture, as the excessive consumption of this element from contaminated food crops leads to toxicity in humans. Rice is the greatest source of dietary Cd intake in populations consuming rice as a staple food. Therefore, reducing the Cd concentration of rice grains for diminishing the potential risk of Cd for human health is a major challenge. This review summarizes the main achievements on Cd accumulation in rice by our research group. Using a positron-emitting tracer imaging system, we succeeded to visualize differences in real-time Cd dynamics from roots to panicles in rice varieties with different Cd accumulation abilities. Several loci or genes responsible for Cd accumulation in rice were found through quantitative trait loci (QTLs) analysis. Using the QTL qCdp7 responsible for efficiently extracting Cd from paddy soils, practical rice varieties for Cd-phytoextraction were developed by DNA marker-assisted breeding. A rice variety named ‘Koshihikari Kan No.1? carrying a mutant allele of OsNramp5 for reducing Cd concentration in rice grains was produced by mutant breeding with ion-beams, and breeding programs have been implemented to transfer this allele into many Japanese rice varieties by DNA marker-assisted breeding. Growing low-Cd varieties aerobically would be a feasible way to simultaneously reduce inorganic arsenic and Cd concentrations in rice grains. These results provide basis for reducing Cd concentration in rice through breeding new varieties.  相似文献   
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The purpose of this study was to assess the extent of genetic erosion of traditional upland germplasm in northern Thailand as a result of gene-flow from distinct strains carrying different genotypes. Even modern variety specific markers have not been developed, there is a comparative population in Laos. Thus, both populations were compared with various characters to evaluate gene-flow from modern variety to landraces. Glutinous and glabrous strains are predominated in Laos. However, such strains were drastically decreased in north–east Thailand. Gene diversity is higher in Thailand, compared to Laos at seven isozyme loci. This was a result of the higher frequencies of Indica strains and heterozygotes in Thailand. Plastid type was also determined by using an INDEL marker. Nearly half of Indica strains carried the Japonica plastid. Heterozygotes also tended to carry Japonica cytoplasm. Such nuclear–cytoplasm substituted strains and heterozygotes were probably generated by natural hybridization. Japonica strains tended to be a maternal donor rather than Indica ones. Or Indica strains would easily release pollens, which grow outside of upland fields.  相似文献   
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A 12-year-old male shih tzu dog was diagnosed as having a calcifying epithelial odontogenic tumour. One and a half years prior to presentation, a mass was noticed on the right mandible by the owners. Radiography revealed irregular, faintly radiopaque material within the tumour. A right hemimandibulectomy was performed, based on the clinical diagnosis of osteosarcoma. Histopathological evaluation of the mandibular mass showed that it was composed of a polyhedral odontogenic epithelial cell nest, fibrous stroma, homogeneous eosinophilic material and rounded calcifying material. The eosinophilic material was visualised by staining with Congo red, and observed under green birefringence by polarisation microscopy. Although the tumour had not recurred 12 months after surgery, the dog was euthanased because of aspiratic pharyngitis. The literature on the clinical behaviour of calcifying epithelial odontogenic tumours in dogs and cats is reviewed.  相似文献   
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Inhalt Möglichkeit einer Chromosomenklassifikation durch eine Trypsin-Giemsa-Bänderungstechnik. Es wird eine modifizierte Trypsin-Giemsa-Bandtechnik für Chromosomen beschrieben, die beim Schwein eine deutliche Bänderung zur Chromosomenidentifikation ergibt. Die Bänderung wird erzielt durch eine Verkärzung der Kolchizineinwirkung auf 30 Minuten und eine Behandlung der 3–5 Tage alten Objektträger mit einer 0,1 % Trypsinlösung (Sörensenpuffer pH 6,8) über eine Dauer von 10–20 Minuten bei 4°C und anschlieβender Färbung mit 2 % Giemsalösung (Phosphatpuffer pH 6,8) für 7–10 Minuten. Mit dieser Technik konnten die 18 autosomalen Chromosomen und die beiden Geschlechtschromosomen des Schweines identifiziert werden. Einzelheiten der G-Bandzeichnung eines jeden Chromosoms dieser Spezies werden beschrieben und in einem Karyotypogramm photographisch und schematisch belegt. Das beschriebene Verfahren kann für Zytogenetiker der Human- und Tiermedizin von Bedeutung sein. Contents In the present paper the authors present a modified trypsin-giemsa chromosomal banding technique showing clear banding patterns for the identification of pig chromosomes. The banding patterns were induced by the reduction of colchicine density or trypsin treatment at a critical temperature of 4°C. Identification of 18 pairs of autosomes and a pair of sex-chromosomes of pig were made successfully. Details of the G-banding patterns of each chromosome were described and illustrated both in a karyotypical photograph and in a schematic diagram. The methods may be of importance to veterinary cytogenetics and genetical pathology, as well as to human medicine.  相似文献   
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