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41.
V A Berezin E N Zhmarev I A Brodskaia G M Shevchenko L S Zashko 《Biulleten' eksperimental'no? biologii i meditsiny》1985,100(7):68-70
The content of neurospecific proteins S-100, GFA and D2 was measured in malignant cerebral tumors by electrophoresis with the use of monospecific antisera. Concomitant measurement of proteins S-100 and GFA is a more reliable diagnostic criterion as to the tumor histogenesis than study of each protein alone. D2 protein appeared to be the most stable specific marker. 相似文献
42.
All plant cells are provided with the necessary rigidity to withstand the turgor by an exterior cell wall. This wall is composed
of long crystalline cellulose microfibrils embedded in a matrix of other polysaccharides. The cellulose microfibrils are deposited
by mobile membrane bound protein complexes in remarkably ordered lamellar textures. The mechanism by which these ordered textures
arise, however, is still under debate. The geometrical model for cell wall deposition proposed by Emons and Mulder (Proc.
Natl. Acad. Sci. 95, 7215–7219, 1998) provides a detailed approach to the case of cell wall deposition in non-growing cells, where there is no evidence for the
direct influence of other cellular components such as microtubules. The model successfully reproduces even the so-called helicoidal
wall; the most intricate texture observed. However, a number of simplifying assumptions were made in the original calculations.
The present work addresses the issue of the robustness of the model to relaxation of these assumptions, by considering whether
the helicoidal solutions survive when three aspects of the model are varied. These are: (i) the shape of the insertion domain,
(ii) the distribution of lifetimes of individual CSCs, and (iii) fluctuations and overcrowding. Although details of the solutions
do change, we find that in all cases the overall character of the helicoidal solutions is preserved. 相似文献
43.
Cristian A. Acevedo Elizabeth Y. Sanchez Juan G. Reyes Manuel E. Young 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(3-4):449-455
It is known that skin releases volatile organic compounds to the environment, and also that its emission pattern changes with aging of the skin. It could be considered, that these compounds are intermediaries in cell metabolism, since many intermediaries of metabolic pathways have a volatile potential. In this work, a simple and non-destructive method consisting of SPME sampling and GC/MS analysis was developed to identify volatile organic emanations from cell cultures. This technique, applied to skin cells culture, indicates that the cells or cell metabolism produce several skin emissions. Chemometric analysis was performed in order to explore the relationship between a volatile profile and the senescence of cell cultures. Volatile profiles were different for cell cultures in different degrees of senescence, indicating that volatile compound patterns could be used to provide information about the age of skin cells. 相似文献
44.
Sacramento Doralice Rodrigues Coelho Rosalie Reed Rodrigues Wigg Márcia Dutra Toledo Luna Linhares Luiz Fernando de Matos dos Santos Marta Gonçalves Azevedo Soares Semêdo Luzia Teixeira de Ribeiro da Silva Antonio Jorge 《World journal of microbiology & biotechnology》2004,20(3):225-229
A promising producer of bioactive compounds isolated from a Brazilian tropical soil was tested for its range of antimicrobial
activities. Strain 606, classified as Streptomyces sp., could not be identified up to species level, suggesting a possible new taxon. The supernatant and 10 extracts and fractions,
obtained by extraction and chromatographic techniques, presented antimicrobial activity using antibiograms. The methanolic
fraction was highly active against pathogenic bacteria, phytopathogenic fungi and the human pathogenic yeast Candida albicans. It also possessed high antiviral activity inhibiting the propagation of an acyclovir-resistant herpes simplex virus type
1 strain on HEp-2 cells at non-cytotoxic concentration. The strong cytotoxic effect suggests an antitumour action.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
45.
46.
J.G. Roddick 《Phytochemistry》1974,13(1):9-25
The literature relating to chemical, biochemical and biological aspects of the steroidal glycoalkaloid, α-tomatine, is reviewed. The alkaloid, which can be used as a starting compound for the synthesis of steroidal hormones, is toxic to a wide range of living organisms. The significance of tomatine to plants which elaborate it is discussed and some possible uses of the compound are mentioned. 相似文献
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