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951.
952.
The influence of ionizing radiation (gamma-rays 60Co) on aggregation activity of the vascular wall and functional (aggregation) platelet activity was studied in the course of the development of acute radiation sickness. The decrease in the aggregation properties of the vascular wall and high functional activity of platelets were inversely proportional, correlating with the periods of acute radiation sickness development and depending on the radiation dose. It is suggested that the changes detected may play a role in the pathogenesis of the development of the postirradiation thrombohemorrhagic syndrome. 相似文献
953.
Amphotericin B (AmB) increased unidirectional Na transport and net transcellular sodium movements across the skin of the frog, Rana pipiens, when added to the solution bathing the corium side, but not from the outer epidermal surface. The AmB response was prevented with pretreatment with amiloride, ouabain and mucosal sodium substitution. Alteration in pH markedly reduced the permeability changes induced by AmB. AmB did not interfere with the increase in sodium transport induced by antidiuretic hormone. The present study demonstrates that AmB interacts with the skin of the frog, Rana pipiens, from the corium side specifically increasing transepithelial sodium transport. The increase in transport apparently occurs through the existing sodium pathway. 相似文献
954.
N Brinkmann M Malissard M Ramuz U R?mer T Schumacher E G Berger L Elling C Wandrey A Liese 《Bioorganic & medicinal chemistry letters》2001,11(18):2503-2506
The alpha-Gal trisaccharide Gal(alpha)(1-->3)Galbeta(1-->4)GlcNAc 11 was synthesized on a homogeneously soluble polymeric support (polyethylene glycol, PEG) by use of a multi-enzyme system consisting of beta-1,4-galactosyltransferase (EC 2.4.1.38), alpha-1,3-galactosyltransferase (EC 2.4.1.151), sucrose synthase (EC 2.4.1.13) and UDP-glucose-4-epimerase (EC 5.1.3.2). In addition workup was simplified by use of dia-ultrafiltration. Thus the advantages of classic chemistry/enzymology and solid-phase synthesis could be united in one. Subsequent hydrogenolytic cleavage afforded the free alpha-Gal trisaccharide. 相似文献
955.
N V Naryzhnaia L N Maslov Iu G Revinskaia Iu B Lishmanov 《Uspekhi fiziologicheskikh nauk》2001,32(4):73-81
The present paper has analyzed relationship between sympatico-adrenal and opioid systems in the pathogenesis of stress heart damage. Based on the our own results and other investigator data the authors make a conclusion that namely relationship between opioid and sympatico-adrenal systems both on the level of the brain and on the periphery determines a degree of the heart resistance to the injury action of severe stress. Myocardial protection by opioids at stress was found to be mediated by the peripheral mu-opioid receptors and was associated with decrease in an activity of sympatico-adrenal system and a inhibition of its effector part. On contrary central opioid system activation leads to an increase in stress heart damage via an increase in sympathetical influence on the myocardium. 相似文献
956.
Biotechnological processes involving bacteria are strongly nonlinear. Therefore, both their productivity and the final product quality may be considerably improved by applying appropriate control strategies to modulate behavior of the bacteria during transitional states. This requires advance identification of indicative signals by off-line investigation (i.e. experimental analysis) and on-line monitoring, (i.e. real time evaluation). A modular scheme is presented for doing this, which incorporates an Extended Kalman Filter and a prediction filter. If this is based on a suitable process-feature vector, which must be chosen in advance, the system can provide sufficient information to trigger appropriate feedback signals. Thus, it can provide a key element in modular situation control, allowing continuously periodic process management. In this publication the individual modules involved, and their assembly into an integrated system are described. Potential problems concerning selection of the feature vector, and experimental results are also discussed. 相似文献
957.
The lagena (the third otolith endorgan in vertebrates) 总被引:1,自引:1,他引:0
V. I. Khorevin 《Neurophysiology》2008,40(2):142-159
In this review, the structure and functions of the lagena (the third otolith organ) in an evolutionary lineage of the vertebrates
are described and discussed. The lagenar macula appears first in the posterior part of the sacculus of elasmobranchs; in these
animals, the lagena is considered to be involved in the balance support (orientation with respect to the gravitation force).
The lagena as a separate endorgan has been described in teleost fishes; in some species, the lagena is connected with the
sacculus, while in other species the interrelations of these structures can be dissimilar. The lagena supplements the functions
of the sacculus; in fishes (animals with no special organ of hearing), it is involved in discrimination of sound oscillations,
identification of the gravitation vector, and orientation in the course of movements within the vertical plane. In amphibians,
the lagena is localized in the posterior part of the sacculus, near the auditory structures; it performs mostly vestibular
and (to a much lesser extent) auditory functions. In amniotes, the lagena was first separated from the sacculus; it is localized
in the cochlear canal, distally with respect to the hearing organ. Information on the functions of the lagena in amniotes
is rather limited and contradictory. Central projections of this organ have been examined practically only in birds. Lagenar
afferents project to the vestibular nuclei and cerebellum, while some fibers come to the auditory nuclei of the medulla. The
lagena in birds can be related to their navigation abilities (birds are supposed to be capable of orienting within the magnetic
field of the Earth due to the magnetic properties of the lagenar otoconia; this structure can also provide detection of movements
along the vertical axis. The close proximity between the otolithic and auditory endorgans in the cochlear canal of amniotes
can be indicative of the functional significance of these interrelations. This aspect, however, remains at present undiscovered.
In mammals (except Monotremata), there is no lagena as an independent endorgan.
Neirofiziologiya/Neurophysiology, Vol. 40, No. 2, pp. 160–178, March–April, 2008. 相似文献
958.
959.
EEG correlates of two main effects of long-term hyperventilation (cyclic breathing similar to rebirthing), namely, psychotic manifestations and sensations in internal organs, are considered. Standard EEGs of 44 subjects were recorded and subsequently treated by multiparametric methods. It was shown that, in the case of psychotic phenomena (hallucinations, visual and auditory images, different scenes, virtual travels, out-of-body experiences, etc.), the changes in the spatial organization of bioelectric potentials as compared with the baseline have different patterns than in the case of sensations in internal organs. The changes are observed in the frontal regions of the cortex: a decrease in spatial synchronization (linear processes) during an increase in spatial disarray (nonlinear processes) of bioelectric potentials and the intensifying of high-frequency β activity. If sensations in internal organs appear, a decrease in the above parameters was observed in the right hemisphere and in posterior cortical areas. The data are discussed from the viewpoint of qualitative specificity of changes in functional states during an altered state of consciousness with manifestations of different psychovisceral phenomena. 相似文献
960.