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The clousness of membrane of rat brain mitochondria isolated in Krebs-Ringer's solution was broken by suspending the mitochondria in distilled water. Function characteristics of lyzed organells did not decrease but were somewhat higher than those of the organells suspended in Krebs-Ringer's solution. The results were discussed in relation to the question of the role of clousness of the mitochondrial membrane in the mechanism of oxidative phosphorylation.  相似文献   
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With recent advances in DNA technology, questions have arisen as to how this technology should be appropriately used. In this article, results obtained from a survey designed to elicit attitudes of college students to prenatal testing and gene therapy for human attributes and psychiatric conditions are reported. The eleven hypothetical disease phenotypes included schizophrenia, alcoholism, tendency toward violent behavior, attention deficit/hyperactivity disorder, depression requiring medical treatment, obesity, involvement in "dangerous" sports activities, homosexuality, borderline normal IQ (80-100), proportional short stature, and inability to detect perfect pitch. Most students supported prenatal genetic testing for psychiatric disorders and behavior that might result in harm to others (i.e., tendency towards violent behavior) and found prenatal genetic testing for human attributes less desirable. However, the lack of unilateral agreement or disagreement toward any one condition or attribute suggests the potential difficulties ahead in the quest for guidelines for the application of new technologies available to manipulate the human genome.  相似文献   
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This article presents the results of three series of experiments on cats, dogs, and lower primates, performed to investigate the structural, neurophysiological, and mediator mechanisms of the corticostriatal systems involved in the organization of behavior. Morphological studies of corticostriatal connections showed that along with the diffuse distribution of afferent terminals within the striatum, there were also elements of topical organization defined by anteroposterior and mediolateral gradients. Neurophysiological experiments on dogs and lower primates were used to study the spike activity of the prefrontal region of the cortex and the head of the caudate nucleus during training to conditioned first- and second-order reflexes and during the solution of complex problems involving delayed spatial selection. Studies demonstrated that while in dogs, most of the neurons recorded showed a transition to responses to the conditioned signal at a particular stage of carrying out a conditioned response, in monkeys all cells recorded showed specific responses at different periods of solving the task at all stages of the study. Neuropharmacological experiments on dogs showed that agents blocking glutamine receptors in the caudate nucleus had more pronounced effects at the phase of developing conditioned movement reflexes. Administration of these agents during the reflex reinforcement phase affected only the differentiation of inhibition. These results lead to the conclusion that the prefrontal area of the cortex and, to some extent, the caudate nuclei, act on incoming information specifying the current dominant need and the states of the external and internal environments, to carry out programmed actions and assess the results of these actions.  相似文献   
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The megakaryocytic apparatus of bone marrow and platelets are discussed as a common system whose physiological purpose is to ensure hemostasis when the integrity of the vascular wall is impaired. The principle of operation of the megakaryocyte-platelet system is synthesis, accumulation, and organization of a potent hemostatic potential, its distribution and dispersal along the vascular bed, if inactive, and its new formation at the moment of and at the site of required hemostasis. At the same time in its early and late major functional performance, the elements of the system are stable-at the early stages of megakaryocytopoiesis to the extent to the appearance of a promegakaryocyte and at the stage of platelet hemostatic cork. At the intermediate stages-that of the mature megakaryocyte divided by demarcation membranes and that of reversible aggregation of platelets which have not lost their individuality, the elements of the system are in an unstable state that is ready for disintegration or in a state that does not exclude its possibilities. In the central phase of its existence, the system is in a disintegrated state and appears as proplatelets and platelets. The mechanism of the dispersal and combination of elements and hemostatic potential of the megakaryocyte platelet system serves the apparatus of structural and contractile proteins, which acts as its system-forming factor.  相似文献   
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Some components of plasma and granulocyte proteolytic system, granulocyte activation degree were evaluated in 15 patients with nonspecific aortic arteritis (NAA) and 12 hereditary hypercholesterolemia (HHC) patients. Catepsin G activity in blood plasma of NAA and HHC patients was higher than in donors 8-9 and 6-fold, respectively (p < 0.001). Granulocyte collagenase activity, spontaneous NBT test values in them were higher than in donors 6 and 4-fold (p < 0.02 and p < 0.01, respectively), 2-fold (p < 0.005 and p < 0.001, respectively). The data obtained confirm the suggestion on the presence of an inflammatory component not only in pathogenesis of NAA, but also in HHC causation.  相似文献   
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