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991.
N. M. Ezhova I. S. Garkushina O. A. Pisarev 《Applied Biochemistry and Microbiology》2011,47(6):635-639
New hydrophilic polymer sorbents comprising reactionary sites which are complementary to a molecule of antibiotic erythromycin
were synthesized by the method of molecular imprinting. A series of similar sorbents without reactionary sites was used for
comparison of sorption characteristics. Sorption of erythromycin on both types of polymer sorbents synthesized was studied
in a wide range of pH and ionic strength. Selectivity of erythromycin sorption on molecularly imprinted cross-linked polymers
was shown to depend on the specific interaction of target molecule with polymer matrix. This type of sorbent is perspective
for the development of antibiotic purification directly from a culture medium Saccharopolyspora erythreus. 相似文献
992.
R. K. Chailakhyan Yu. V. Gerasimov A. I. Kuralesova N. V. Latsinik E. N. Genkina M. R. Chailakhyan 《Biology Bulletin》2001,28(6):575-584
We present the results of a study on the proliferative and differentiation potential of individual clones of stromal fibroblasts growing in monolayer cultures of bone marrow cells. Each precursor cell yielding a large colony in primary culture is capable of up to 34 doublings in vitro. The transplantation of clones or monoclonal strains of stromal fibroblasts into the open system results in the formation of microenvironment consisting of the bone and reticular tissue and is suitable for the differentiation of all three lines of hemopoiesis. Evidence has been obtained that, in a closed system, individual clones are capable of differentiation into the bone, cartilaginous, and reticular tissues. In other words, the adult organism has a common cell precursor for these tissues. 相似文献
993.
994.
Experiments on cyanobacterial cultures showed that initial exposure to copper at concentrations of 0.01–0.05 mg/l not only has a direct toxic effect, but also significantly modifies the copper tolerance of cyanobacteria for repeated exposure. The response to repeated exposure and the mechanism of tolerance depend on the strength of the initial effect of copper and the extent of heterogeneity of the initial cyanobacterial population. 相似文献
995.
996.
V. N. Barai A. I. Zinchenko L. M. Zalashko L. A. Eroshevskaya I. A. Mikhailopulo 《Biotechnology letters》1995,17(6):599-602
Summary The title compound was prepared by a three-stage enzymatic procedure consisting of (i) RNA hydrolysis to a mixture of ribonucleosides using intact mycelium of Spicaria violacea, (ii) transribosylation of exogenous adenine employing whole cells of Escherichia coli as a biocatalyst, and (iii) conversion of formed adenosine into ATP by the enzymes of alcohol fermentation and the kinases extracted from baker's yeast. 相似文献
997.
A frameshift mutation (2869insG) in the second transmembrane domain of the CFTR gene: identification, regional distribution, and clinical presentation.
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998.
Biophysics - The relationship between pandemic morbidity and the shared participation of a pandemic variant in epidemic process has been studied based on the example of the first pandemic wave of... 相似文献
999.
1000.
Immunochemical analysis of the cAMP-dependent protein kinase regulatory subunit type II was performed with the use of two rabbit antisera elicited to a free R-subunit from pig brain and to a RcAMP complex. Quantitative precipitation of the homogeneous antigen revealed six determinants on the R-molecule. Of these at least one is localized in the R-fragment (37 kD), the others--in the N-terminal part of the R-molecule. The antigenic determinants seem to be remoted from the cAMP-binding centers, since the attachment of the affinity purified antibody Fab-fragments to the R-subunit did not influence the cAMP-binding activity of the latter. The antibodies to RcAMP caused dissociation of the holoenzyme. The antibody Fab-fragment binding to the R-subunit prevented its association with the catalytic subunit. The results of immunochemical analysis suggest that the R-subunit adopts different conformations when bound to cAMP or to the catalytic subunit. 相似文献