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1.
Hugo R. Permingeat Maria V. Romagnoli Juliana I. Sesma Ruben H. Vallejos 《Plant Molecular Biology Reporter》1998,16(1):89-89
An easy, reproducible and fast procedure to isolate DNA from cotton leaves is described. The addition of 0.5 M glucose in the extraction buffer avoids browning by polyphenolic compounds and improves the quality of DNA for molecular analysis. The DNA yield ranged between 150–400 mg per gram of fresh tissue. The DNA was suitable for digestion by restriction enzymes and amplificatiion by Taq DNA polymerase. 相似文献
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Summary Production of trace levels of carbon monoxide was consistently observed in the off-gas of a laboratory anaerobic digester fed Waste Activated Sludge. Inocula from this digester was enriched for acetate and methanol utilizing methanogenic populations. These enriched inocula were then monitored in batch assays for carbon monoxide and hydrogen production. Results demonstrated that carbon monoxide is produced during methanogenesis on both substrates. Subsequent utilization of CO was observed to occur after methane production was essentially complete for the assays conducted with methanol. Carbon monoxide evolution during methanogenesis on acetate displayed a markedly different trend from that observed from methanol. 相似文献
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P Vago S Abdoukhil F Odier H Mion J P Bureau 《Comptes rendus des séances de la Société de biologie et de ses filiales》1987,181(6):658-665
Flow cytometric analysis of cell DNA content in the mouse C 57 BL/6 shows better results with fine needle aspiration than with mechanical dissociation of the tissues. There is no difference fresh and deep frozen stored tissues. In the liver, it has been found two cell populations with different DNA content including diploid and tetraploid cell lines. In the spleen and the thymus, only diploid cells are encountered with different cell cycles belonging to the organ. 相似文献
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The possibility of using the nutritionally versatile bacterium Pseudomonas cepacia to produce poly-β-hydroxyalkanoic acid was evaluated. Chemostat culture showed that growth of P. cepacia became nitrogen limited when the molar carbon-to-nitrogen ratio of the medium fed into the fermentor was above 15. When grown under nitrogen limitation in batch culture with fructose as the sole source of carbon, P. cepacia accumulated poly-β-hydroxybutyric acid (PHB) in excess of 50% of the dry weight of its biomass. In batch culture, almost no PHB was produced until the onset of nitrogen limitation. After this point, PHB was produced at a linear rate of 0.12 g liter−1 h−1 (from a constant value of 1.6 g of cellular protein liter−1). PHB produced by P. cepacia had a weight-average molecular weight of 5.37 × 105 g mol−1 and a polydispersivity index of 3.9. Poly(β-hydroxybutyric acid-β-hydroxyvaleric acid) copolymer was produced with a poly-β-hydroxybutyric acid-poly-β-hydroxyvaleric acid ratio of up to 30% by weight when propionic acid was added to the medium. 相似文献
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Résumé Des micro-organismes présentant les caractères des mycoplasmes ont été observés dans les tissus adipeux et cardiaques de larves
du Coléoptère ScarabeideMelolontha melolontha, soit sur des tissus prélevés directement sur larves, soit maintenus en culture d'organes pendant 15 jours à 3 semaines.
Summary Microorganisms with characteristics usually observed in mycoplasms when examined under the electron microscope have been seen in fat and cardiac cells from larvae ofMelolontha melolontha, [Scarabaeidae Coleoptera]. These observations have been made either on tissues taken directly from larvae or kept in organotypic culture for 15 days to 3 weeks.相似文献
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We applied a modified immunofluorescence and immunoperoxidase method, utilizing labeled Blastomyces dermatitidis antigens, to look for specific antibody-bearing B/ plasma cells in the tissue infiltrates of blastomycosis lesions induced in hamsters. No specific anti-blastomyces antibodies were detectable by this method, although such antibodies were present in blood samples as demonstrated by routine immunodiffusion techniques. These studies suggest that humoral immune reactions do not play a major role in the pathogenesis of lesions of blastomycosis in hamsters. 相似文献