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11.
By means of retrograde transport methods, CoCl2 and horseradish peroxidase, localization and morphological peculiarities of the CNS neurons, that innervate lips and oral area, have been studied in the pond snail (Gastropoda). The neurons, sending their processes into the anterior and middle labial nerves, are found nearly in all ganglia of the parapharyngeal nervous ring on the distal and ventral surface. In the cerebral ganglia they situate as several symmetrical groups. Among the neurons revealed, there are cells with rather local distribution of the terminal branches of the processes in the CNS neuropil and neurons with vast branching areas in the neuropil not only of its own ganglion, but also of the neighbouring ones. The problem concerning the zones of possible intersensory interaction in the cerebral ganglia is discussed and presence in them, together with complex reflectory arches, of bisegmental reflectory arches is considered.  相似文献   
12.
The density and sedimentation characteristics of ribonucleoproteins (RNP) containing genomic RNA from influenza virus and RNA complementary have been studied. Radioactive RNA from infected cells has been used for analysis. RNA classes of interest were isolated by reannealing with abundant nonradioactive genomic and complementary RNA and separation of resulting duplexes in electrophoresis. The RNP containing antigenomic virus-specific RNA are practically identical to "genomic" RNP for their sedimentation and density characteristics. The "plus" RNP is characterized by the stoichiometric mode of RNA protein interaction.  相似文献   
13.
The assumption is made that ionizing radiation induces cholesterogenesis activation in different cells of mammalian organism as an early reaction to the harmful effect necessary for restoration of biomembranes. Liver cells activate adaptively the cholesterol synthesis in the animal body irradiated with lethal doses in response to the injury to radiosensitive cells in order to make them recover and compensate for their functions (with the gastrointestinal syndrome, for instance, to compensate for the cholesterol-producing function of the intestine and to make it recover). With lethal radiation doses, a change in the lipid content and metabolism of microsomal membrane lipids of the liver is associated with activation of synthetic functions of the liver due to compensation of the injury to radiosensitive tissues.  相似文献   
14.
As a result of chronic stress, anxiety appeared in the rats behaviour, motor activity increased, heart rate quickened, blood pressure raised, conditioned instrumental alimentary reflexes missed, the duration of deep phases of sleep lowered, time of falling asleep became longer, the number of awakening increased. The change in quantitative characteristics of sleep was accompanied by its worsening, especially of rapid sleep. Administration of substance P (SP) eledoisin hexopeptide (EH) (250 mcg/kg), 100-200 mcg/kg of delta sleep peptide and 10 mcg/kg of ethylcrotyl barbiturate improved the rats behaviour and sleep parameters. Calipnon accelerated falling asleep. Delta sleep peptide increased sleep duration. SP and EH restored not only the quantitative characteristics of deep phases of sleep but greatly improved their quality: lowered the blood pressure disrupted tachycardia, normalized the conditioned activity.  相似文献   
15.
16.
The ultrastructural study of man's cytoskeleton of podocytes is carried out. Populations of podocytes with two different types of structure of the cytoskeleton in dependence on age (2, 4, 6, 37 and 65 years) is revealed in kidneys. The first type of cytoskeleton of the podocyte is peculiar for children's age and is characterized by branched, high density microfilament network, expressed by system of microtubules and single myofilaments. The intermediate filaments here are either utterly absent or present so feebly they find themselves "disguised" by other strongly developed components of cytoskeleton and revealing them with the help of technique of electron microscope is impossible. In kidneys of adults, and especially of old aged persons podocytes with other type of organization of the cytoskeleton are mainly identified. The distinctive signs of the last are bundle arrangement of microfilaments, plural bundles of intermediate filaments and individual microtubules. This study permits to make a conclusion that during individual development and growing old in kidneys of high animals and man, probably, physiological changes causing morphological reconstruction of cytoskeleton which is accompanied by intensive development of intermediate filaments' system with simultaneous "involution" of microtubules and microfilaments' systems take place.  相似文献   
17.
A technique of highly selective affinity labelling, which includes covalent modification of the enzyme-T7A2 promoter complex with reactive oligonucleotide derivatives and subsequent elongation of the attached oligonucleotide residue with a radioactive substrate was used to study the product-binding site of E. coli RNA polymerase. Different oligonucleotides complementary to the T7A2 promoter (with lengths ranging from 2 to 8 residues) containing 5'-terminal phosphorylating, alkylating or aldehyde groups were used for the labelling. The procedure resulted in labelling DNA and beta-, beta'- or sigma-subunits of the enzyme, which are therefore believed to contact with growing RNA in the course of initiation. Consideration of the labelling patterns as a functions of the oligonucleotide's length as well as of the structure and chemical specificity of the reactive groups led to a tentative topographic scheme of the RNA polymerase product-binding region.  相似文献   
18.
Multiplex methylation-sensitive PCR and methylation-specific PCR were employed in studying the methylation of CpG islands in the p16/CDKN2A and p14/ARF promoter and the first exon regions in non-small cell lung cancer (54 samples) and acute B-cell lymphoblastic leukemia (61 samples). Differences in methylation were detected between types of neoplasia as well as between CpG islands studied within the same types of tumors. High level of the p16/CDKN2A first exon CpC island methylation was revealed in non-small cell lung cancer (68%) and in acute B-cell lymphoblastic leukemia (55%) and the CpG island of p14/ARF first exon was nonmethylated in these types of tumors. The methylation of CpG-rich fragments of genes p16/CDKN2A and p14/ARF promoters was analysed. As was found out, CpG islands located in 5' areas of one and the same gene can differ in methylation frequencies. The comparison of sensitivity between methylation-specific PCR and methylation-sensitive PCR used in the methylations studies was carried out.  相似文献   
19.
Blood lymphocytes from 26 women were cultivated in RPMI-1640 for 72 hrs with or without dexamethasone, dbcAMP, and TPA. Androstenedione conversion was most often activated by the dbcAMP, then by Dex and TPA. Response to dbcAMP was most obvious in women under 50, whereas response to Dex--in women over 50. Aromatase inhibitor fadrosol displayed a tendency towards prevention of the activation of androstenedione conversion in cultivated lymphocytes. A possibility of aromatase gene induction in cultivated lymphocytes cannot be completely excluded and demands further investigation with the aid of molecular-genetic methods.  相似文献   
20.
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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