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Identification of differentially expressed genes by restriction endonuclease-based gene expression fingerprinting. 总被引:8,自引:3,他引:5 下载免费PDF全文
A novel method for identification of differentially expressed genes has been developed. It is based on the consecutive restriction digestions of 3' terminal cDNA fragments to produce a fingerprint of gene expression. cDNA molecules are synthesized using a biotinylated oligo(dT) primer, digested with a frequently cutting restriction endonuclease and the 3'-terminal restriction fragments are isolated using streptavidin microbeads. After amplification by PCR, cDNA fragments are immobilized again on streptavidin beads, radiolabeled and treated sequentially with a set of restriction endonucleases. The products of individual enzymatic reactions from two or more different RNA populations are resolved by polyacrylamide gel electrophoresis and compared to reveal differentially expressed genes. This strategy enabled us to identify and clone the fragments of five genes expressed differentially in murine thymus and spleen. One of the genes was found to encode terminal deoxynucleotidyl transferase; others are apparently previously unknown genes. 相似文献
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N G Ivanova 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1984,34(4):657-661
In response to electro-skin stimulation of the left forelimb eliciting its flexion,--an escape instrumental reflex was elaborated in five dogs in the form of extension of the stimulated limb (pressure on the support), i.e. a reaction antagonistic to the inborn one. The reaction was elaborated due to conditioned transformation of the unconditioned flexion: the flexion became gradually inhibited and the new form of reaction, previously not inherent in the animal increased and became stable. Such transformation of one reaction into another is connected with the reorganization of inborn coordinations. 相似文献
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The keeping of guinea pigs in a thermochamber at 37 degrees C for 3 days resulted in increased releasing of neurohormones of the posterior lobe of the hypophysis. By the end of the 3d day there was no substantial difference between the average logarhythm of the volume of cell nuclei of the supraoptic nucleus of experimental animals and that of intact animals. Injection of ACTH after a preliminary three-day presence of the animal in the thermochamber caused a pronounced inhibition of the hypothalamo-hypophyseal neurosecretory system (HHNS). The HHNS of animals subjected to 3-day-long continuous exposure to high temperature, in contrast to the HHNS of intact animals is not capable to increase its activity in responses to stress (immobilization). 相似文献
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Orlova AG Maslennikova AV Golubiatnikov GIu Kamenskiĭ VA Shakhova NM Babaev AA Snopova LB Ivanova IP Plekhanov VI Prianikova TI Turchin IV 《Biofizika》2011,56(2):349-355
The potentialities of diffuse optical spectroscopy for the noninvasive estimation of the oxygen state of experimental tumors have been demonstrated. The distribution of total, oxygenated and deoxygenated hemoglobin, as well as the level oxygen saturation of blood have been shown using two tumor models differing in the histological structure and functional characteristics. The results obtained by the optical method have been verified by immunohistochemical examination of tissue specimens with the exogenous hypoxia marker pimonidazole. 相似文献
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A. G. Orlova A. V. Maslennikova G. Yu. Golubyatnikov V. A. Kamensky N. M. Shakhova A. A. Babaev L. B. Snopova I. P. Ivanova V. I. Plekhanov T. I. Pryanikova I. V. Turchin 《Biophysics》2011,56(2):304-308
The potentialities of diffuse optical spectroscopy for noninvasive estimation of the oxygen status of experimental tumors have been demonstrated. The distribution of total, oxygenated, and deoxygenated hemoglobin, as well as the level of oxygen saturation of blood have been assessed using two tumor models differing in the histological structure and functional characteristics. The results obtained by the optical method have been verified by immunohistochemical examination of tissue specimens with an exogenous hypoxia marker pimonidazole. 相似文献
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A. V. Arutyunyan M. A. Ivanova D. I. Kurlyand Yu. S. Kapshin S. B. Landa S. T. Peshekhonov E. A. Drobchenko I. V. Shevelev 《Biophysics》2011,56(4):644-650
Changes in the rigidity of the polymeric chain of phage λ double-strand DNA have been studied by laser correlation spectroscopy. It was shown that, as the ionic strength increases, the effect of the screening of the hydrodynamic interaction of the links of the polymeric chain specific for polymeric coils arises in a DNA solution. It is assumed that the screening occurs when the threshold of the overlapping of DNA coils is achieved. The overlapping of coils is the result of a previously observed significant rise of DNA coil size from abnormally small DNA coils in low ionic strength buffers (about 10−2 M Na+ or less) to maximum possible large coils in the 5SSC and 5SSC-like buffers. Further analysis of the far interlink interactions in linear lambda phage DNA coils in similar buffers at pH 7 and 4 confirms the earlier proposal about the role of H+ ions in the appearance of abnormally small DNA coils. The abnormal decrease in the DNA coil size in low ionic strength buffers is not a specific feature of λ phage DNA only. 相似文献
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A. B. Shcherbakov V. K. Ivanov N. M. Zholobak O. S. Ivanova E. Yu. Krysanov A. E. Baranchikov N. Ya. Spivak Yu. D. Tretyakov 《Biophysics》2011,56(6):987-1004
Nanocrystalline ceria possesses a unique complex of physical and chemical properties making it highly bioactive material. In this review, modern data on the action of nanocrystalline ceria on cells, micro- and macroorganisms are analyzed. Special attention is paid to the analysis of the factors affecting protective properties of CeO2 with respect to the living systems. 相似文献
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