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821.
Alkaline sucrose solution was demonstrated to be a good solvent for the solubilization of water-insoluble drugs. At high concentration
and alkaline pH, sucrose solubilizes water-insoluble molecules through intramolecular conformations. Tetracyline and chloramphenicol,
when dissolved in alkaline sucrose solution, retained their bactericidal activity. Gel permeation-chromatography analysis
and atomic-force-microscopy studies confirmed the formation of sucrose-antibiotics complex. 相似文献
822.
A V Martynikhin I V Poliakov A A Timofeev E V Rubakhina 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1985,35(2):232-237
The influence of spatio-temporal factors (spatial heterogeneity of distribution of the numbers sought for in the matrix of data, processes of learning and development of fatigue, periodic attention oscillations) of the character of solving the task of searching the numbers in a matrix of 176 three-figure numbers (16 lines, 11 columns) was studied in 39 operators. The possibility was shown to use the characteristics obtained for evaluation of professionally important abilities of an operator working at the display. 相似文献
823.
Lymphocyte stimulation in Candida albicans infections 总被引:2,自引:0,他引:2
824.
825.
The molecular structure of the mitochondrial glycoprotein capable of forming Ca2+-selective and ruthenium red-sensitive conductance channels when incorporating into a model membrane are studied. The glycoprotein is shown to be a complex consisting of the glycoprotein itself and a low-molecular component which may be attributed to the substance of a peptide nature. A technique is elaborated to divide the complex into constituents. It is found that the channel-forming part of the complex is its peptide component. The glycoprotein component is unable to transport Ca2+ and, probably, fulfills a regulatory function. 相似文献
826.
Development of ovaries in bovine fetuses 总被引:1,自引:0,他引:1
The growth of ovaries, development of germ cells, formation of sex cords, folliculogenesis and dependence of these processes on the gonad morphogenesis stages were studied on 68 embryos and foetuses at the age of 1.5 to 9 months. Sex differentiation of ovaries was shown to take place in 1.5 month old embryo. The cords of connective tissue's cortical stroma appear also in 1.5 month old embryo, they develop in the dorsoventral direction and reach the gonad's covering epithelium in 6 month old foetuses. The formation of the medulla rudiment starts in 1.5 month old embryo when the gonad is separated from mesonephros and connected with it via the ovary gate. In 4 month old foetuses the ovary net transforms into a stellate structure. Important morphogenetic processes, such as the development of the ovary somatic elements, entry of the oocytes into meiotic prophase, formation of the sex cords and folliculogenesis, develop in the dorsoventral direction Germ cells in 9 month old foetuses are enclosed into primordial or, growing follicles. 相似文献
827.
828.
829.
Using fluorimetric and polarographic determination of cell respiration, metabolic reactions of the carotid body of rats to adequate stimulation have been revealed. Functional relationships of the dose--effect type, which were found for these reactions, may be approximated by equations which are similar to those describing the unconditioned reflexes from the carotid chemoreceptors. However, reactions of the metabolics systems of the carotid body account for the perception of not all chemical stimuli, but only of acids and some alkaloids. These data reveal the heteregeneity of the carotid chemosensory system not only in the amphibians (which was known earlier), but in mammals as well. 相似文献
830.