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81.
82.
Tomáš Trnka Miloslav Černý Anna Ya. Shmyrina Alexander S. Shashkov Alexander F. Sviridov Oleg S. Chizhov 《Carbohydrate research》1979,76(1):39-44
13C-N.m.r. spectra of all possible 1,6:2,3- and 1,6:3,4-dianhydro-β-D-hexo-pyranoses and their O-acetyl and deoxy derivatives are presented. Relations between chemical shifts of certain carbon atoms and the structure of the dianhydrides are outlined, and their application in structural analysis is discussed. Inversion of configuration of the oxirane ring from the endo to the exo position is associated with typical upfield-shifts for oxirane-ring carbon atoms C-2 or C-4, respectively. Possible inter-relationships between 13C-chemical shifts and steric and polar interactions in the dianhydro derivatives are discussed. 相似文献
83.
84.
The Concanavalin A agglutinating system of cell membranes. 总被引:1,自引:0,他引:1
Nejat Düzgüneş 《Bio Systems》1975,6(4):209-216
The hopes raised by the finding of differential Concanavalin A (Con A) agglutinability of normal and transformed cells in efforts to quantify differences between these cell lines seem not to have been justified. In this paper, the development of information on the mechanism of action of Con A on the cell surface, as well as the theories put forward at each stage of this development are surveyed. In this respect, investigations on Con A constitute a case history in biological research. The involvement of glycoproteins and galactosyltransferases in cell-cell interactions and their relations to Con A are also reviewed. 相似文献
85.
In this study, the simultaneously recorded and selectively averaged evoked potentials in some of the structures of the auditory pathway (acoustical cortex, medial geniculate nucleus, inferior colliculus), in the reticular formation and the hippocampus of the awake cat as well as the simultaneous amplitude frequency characteristics of these structures are given. The power spectral density functions computed from the simultaneously recorded spontaneous activity of these structures are also presented. Using these results, the following analyses are accomplished: (1) determination of the dynamics of potentials simultaneously obtained from various brain structures, in order to evaluate the common features of their system characteristics; (2) determination of the relationship (or interactions) between rhythmic activity and evoked potentials of the brain, and (3) elaboration of a working hypothesis for the dynamics of potentials of the brain. Some suggestions and comments are also made for investigators working toward theories or dynamic models of signal transmission in the brain. 相似文献
86.
Two new species of the genus Quadroppia Jacot, 1939, Quadroppia (Coronoquadroppia) squarrosa sp. n. and Quadroppia (Quadroppia) foveolata sp. n. are described and illustrated from Turkey. They were collected from soil and litter under pear trees (Pyrus communis) and moss on rock, respectively. 相似文献
87.
S. V. Pigoleva N. S. Zakharchenko A. V. Pigolev Yu. A. Trotsenko Ya. I. Buryanov 《Applied Biochemistry and Microbiology》2009,45(6):604-609
The influence of colonization of sugar beet (Beta vulgaris var. saccharifera (Alef) Krass) and white cabbage (Brassica oleracea var. capitata L.) plants by methylotrophic bacteria Methylovorus mays on the growth, rooting, and plant resistance to phytopathogen bacteria Erwinia carotovora was investigated. The colonization by methylobacteria led to their steady association with the plants which had increased
growth speed, root formation and photosynthetic activity. The colonized plants had increased resistance to Erwinia carotovora phytopathogen and were better adapted to greenhouse conditions. The obtained results showed the perspectives for the practical
implementation of methylobacteria in the ecologically clean microbiology substances used as the plant growth stimulators and
for the plant protection from pathogens. 相似文献
88.
89.
90.
O. I. Iatsyna E. O. Stakhovsky Ya. A. Sheremet S. I. Spivak O. E. Stakhovsky O. N. Gavrilyuk Yu. V. Vitruk A. I. Emets Ya. B. Blyum S. V. Vernygorodskyi 《Cytology and Genetics》2011,45(4):201-207
The TUNEL reaction was used to study induced apoptosis in the tumor cells of urinary bladder cancer (UBC) patients. It has
been shown that an increase in the values of induced apoptosis correlates well with the indicators showing a tumor’s corresponding
response to the application of neoadjuvant chemotherapy, using the gemcitabine-cisplatin regimen. It has been concluded that
assessing the level of induced apoptosis in UBC tumor cells using the TUNEL assay enables making a prognosis for the efficacy
of chemotherapy at the single-cell level in patients with this type of cancer. 相似文献