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931.
Relationships between marine diatoms and the bacterium Listeria monocytogenes have been studied by routine algological methods and high-resolution video-enhanced differential interference contrast light microscopy. The study showed that the relationship between the listeria and the benthic diatom Navicula sp. has a parasitic character, whereas the relationship between the listeria and the planktonic diatom Phaeodactylum tricornutum is protocooperative. 相似文献
932.
Nine larvocysts of Echinococcus granulosus isolated from nine patients and one cyst derived from a naturally infested cattle have been examined. Genomic typing was carried out in order to identify strains of E. granulosus. All DNA samples were shown to have the same genotype, E. granulosus G1. 相似文献
933.
Pecherskiĭ AV Semiglazov VF Loran OB Karpishchenko AI Pecherskiĭ VI Mazurov VI 《Tsitologiia》2006,48(10):862-866
This research work is devoted to an important subject--study of the impulse regime of the incretion of a series of hormones among men with partial androgen deficience of aging men (PADAM). The results of this study suggest that PADAM leads to a breakdown of the impulse regime of incretion of a series of hormones, including luteinizing hormone (LH), follicle stimulating hormone (FSH), and somatotropic hormones (STH), as well as cortisol and insulin among men of older age groups. These changes accompany the development of metabolic syndrome (X-syndrome); their development can be inversed through androgen-replacement therapy. 相似文献
934.
Patrushev MV Patrusheva VE Kasymov VA Evdokimovskiĭ EV Ushakova TE Gaziev AI 《Tsitologiia》2006,48(8):684-690
A nessessary condition for normal functioning of mitochondria is the maintenance of certain numbers of intact mtDNA molecules. In the present study, we investigasted changes in the number of mtDNA copies in brain and spleen cells of mice subjected to irradiation. For the first time, we observed the irradiation-induced output of mtDNA fragments into brain and spleen cell cytosol. In the cytosol of these cells, examined in mice 5 h after 5 Gy irradiation, 1841 h.p. mtDNA fragments were detected able to persist for at 3 weeks. In addition, larger fragments of mtDNA (10,090 b.p.) were detected in the cytosol of brain cells of irradiated mice. The occurrence of mtDNA fragments in the cytosol of brain cells is accompanied with an increase in the number of mtDNA copies in the mitochondrial matrix. The induction of mtDNA replication in brain cells of irradiated animals may be considered as a compensatory reaction in response to mtDNA damage. A sharp decrease in the amount of mtDNA copies in the mitochondrial matrix of spleen cells on the first day after irradiation may be considered as apoptosis development. However, the compensatory reaction in brain cells was also noticed but in later terms. 相似文献
935.
A study was made of changes in the rates of respiration, heat production, and membrane characteristics in cells of excised roots of wheat seedlings under the modulation of plasma membrane ion permeability by two membrane active compounds: valinomycin (20 microM (V50)) and chlorpromazine (50 microM (CP50) and 100 microM (CP100)). Both compounds increased the loss of potassium ions, which correlated with the lowering of membrane potential, rate of respiration, and heat production after a 2 h exposure. The differences in alteration of these parameters were due to specific action of either compound on the membrane and to the extent of ion homeostasis disturbance. V20 had a weak effect on the studied parameters. V50 caused an increase of the rate of respiration and heat production, which enhanced following a prolonged action (5 h) and were associated with ion homeostatis restoration. The extent of alteration of membrane characteristics (an increase of potassium loss by roots, and lowering of cell membrane potential) as well as energy expense under the action of CP50 during the first period were more pronounced than in the presence of V50. During a prolonged action of CP50, the increase of respiration intensity and heat production correlated with partial recovery of ion homeostatis in cells. Essential lowering of membrane potential and substantial loss of potassium by cells, starting from the early stages of their response reaction, were followed by inhibition of respiration rate and heat production. Alterations of the structure and functional characteristics of excised root cells indicate the intensification of the membrane-tropic effect of a prolonged action of CP100, and the lack of cell energy resources. 相似文献
936.
937.
Spivak IM Smirnova TIu Gruzdev NV Shneĭder OV Abramchenko VV Spivak DL 《Tsitologiia》2006,48(10):875-882
The paper presents results of a pilot study of genetic correlates of adaptive strategies characteristic for religious and (or) spiritual people in stress, induced by unusual and (or) extreme conditions. Birth stress, experienced by 79 young normal female urban dwellers Ss in the course of late pregnancy, giving birth, and the immediately following period post partum, was chosen as model of stress in general. Their state, as well as the state of the child, was monitored in each case by professional physicians, and assessed according to standard obstetric procedures. 3 kinds of standard psychological tests, providing assessment of neurotization, creativity, and the scope of religious/spiritual sensations, were conducted. The latter formed focal point of our research. As in has recently been supposed, religious/spiritual people tend to be more adaptive in illness and stress, which is quite important for clinical practice. The first aim of our study was to test whether religious/spiritual sensations in stress tend to occur as part of general neurotization; or, as part of creative response in the service of the ego; or, finally, they form a specific dimension of adaptive strategies. In home to simultaneously assess possible genetic determination of each of these options, we have introduced intro our study a module of assessment of genetic I/D polymorphisms of ACE gene, primarily linked to the status of the renin-angiotensin system. As a result of factor analysis, existence of 3 strong trends was demonstrated. 1. Neurotization, creativity, religious/spiritual processes tend to form 3 independent aspects of response of normal humans to birth stress. 2. Frequency of occurrence of D-allele tends to reveal strong correlation with only one of these 3 options, which is the generall level of neurotization. The latter conclusion corresponds well to what is currently known about the role of renin-angiotensin system primarily in regulation of cardiovascular system, and probably adaptation to stress. 3. Frequency of occurrence of D-allele in the mother tends to reveal inverse correlation with the Apgar index of the child (assessment of its physiological state in the course of the first several minutes after birth, based upon such characteristics as heart beat rate, ability to independent breathing, state of the skin, etc.), and is not linked to usual standard biometric parameters of newborn children. Continuing to work on this model, we intend to formally assess possible impact of heredity via other genes upon psychological, especially religious and spiritual aspects of adaptation to stress of women in birth; and also approach to possible genetic correlates of the state of newborn children. 相似文献
938.
Polypeptides with cytostatic activity are known to be present in animal tissues during winter dormancy. A 1-10 kDa polypeptide fraction with cytostatic activity was obtained from brain tissue of hibernating ground squirrels and cold-adapted Yakut horses. The pattern of cytostatic activity of this fraction towards tumor cells is of great interest. We present results testifying to cytostatic activity of this fraction towards the Ehrlich ascitic carcinoma cells. The cytostatic effect is realized in tumor cells at the genetic level. 相似文献
939.
Pavlova IV Levshina IP Vanetsian GL Pavlov IuV Shuĭkin NN Ziablitseva EA 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2006,56(1):65-74
Different behavioral reactivity of rabbit groups differentiated by locomotor activity in the "open field" was revealed during exposure to emotional stimuli (rustle, loud sound, pressuring on back of the neck, vibroacoustic tactile stimulation of an ear). In passive rabbits, the active locomotor reactions were induced harder and freezing was obtained easier than in active animals. During exposure to sound stimuli, passive rabbits increased their locomotion more rarely than active animals, pressing on back of the neck produced longer freezing, a threshold of defensive ear shaking in response to a vibroacoustic stimulus in passive animals was highest. Training to mild immobilization increased the threshold of defensive responses in active rabbits and animals of the intermediate type. Changes in respiratory parameters were correlated with behavioral reactions to emotional stimuli. The duration of exhalation and respiratory cycle increased during freezing and increased during enhanced locomotion. The duration of inhalation decreased in response to emotional stimuli irrespective of a behavioral reaction. The respiratory reactions to emotional stimuli differed in rabbits of different groups. The respiratory rate more frequently changed in passive rabbits than in animals of other groups. Passive animals reacted mainly by exhalation, active rabbits and animals from the intermediate group predominantly responded by inhalation. 相似文献
940.
Golimbet VE Alfimova MV Gritsenko IK Ebshteĭn RP 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2006,56(4):457-463
Dopamine neurotransmissin is thought to play a relevant role in behavioral reinforcement system. Polymorphism of the genes involved in dopamine system has been reported for association with psychological traits related to impulsive and sensation seeking behaviors. The study was aimed at a search for association of catechol-O-metyltransferase (COMT) and dopamine receptor D4 (DRD4) gene polymorphism with personality traits in Russian population. A sample comprised 130 subjects. It was found that carriers of the Met/Met COMT genotype had higher scores of novelty seeking as compared to those with the Val/Val and Met/Met genotypes. The association was observed in women only. In the presence of the C allele of the DRD4 gene, females with the Met/Met genotype demonstrated higher scores on extraversion and hypomania. The results are consistent with the current theoretical concepts on the regulation of dopamine neurotransmission in the brain. 相似文献