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An experiment layout based on a pulsed capillary microwave torch and making it possible to excite an explosive emission microplasma on a metal surface in open air is implemented for the first time. It is shown that a microrelief in the form of micron-size microcraters forms on the initially smooth surface under the action of microsparks. As a result, the maximum secondary electron emission yield σmax decreases from ~2 for the untreated surface to ~0.4 for the rough treated surface and remains low for a long time when exposed to atmospheric air.  相似文献   
284.
Using the flash photolysis technique the kinetics of recombination of carbon monoxide with ferrocytochrome P-450 LM-2 was investigated. Ferrocytochrome P-450 was incorporated into liposomes prepared from different lipids: from microsomal lipids, phosphatidylcholine from egg yolk, dipalmitoylphosphatidylcholine. It was found that the activity and structure of ferrocytochrome P-450 conformers is affected by the lipid microenvironment. The kinetics of the CO-binding is affected also by the nature of lipids.  相似文献   
285.
The temporal parameters of a process of vacuum gap commutation under exposure to a nanosecond pulse of laser radiation incident on the cathode has been studied depending on the radiation energy. Based on the experiment data, it is suggested that a glow discharge is initially ignited in electrode erosion products under exposure to the laser pulse, which due to development of the ionization-overheating instability undergoes the contraction of current channel and transits to an arc discharge. With the radiation energy exceeding a threshold value, the radiation (incident on the cathode) accelerates directly the instability development and the glow discharge transition to the arc discharge due to the radiation absorption in the discharge plasma.  相似文献   
286.
The analysis of the authors and published data allowed to conclude that the blood-brain barrier was a complex structural-functional system. Its basic components are endothelial cells, basal membrane, pericytes, tissue basophils, and astrocytes. The role of these structural elements in the permeability of blood-brain barrier has been studied. Organ-specific peculiarities of the brain tissue basophils have been established in rats, cats, and dogs. The astrocyte-capillary complexes were found to be very reactive, and at the same time, very plastic CNS structures.  相似文献   
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The correlations between nitric oxide products (NO x ) and the angiotensin-converting enzyme (ACE) activity and malondialdehyde (MDA) were studied in the blood serum of patients with thoracic wounds (the test group) 1, 3, 7, and 14 days after the injury. The severity of a patient's state scored from 8 to 15 on the APACHE II scale. The control group comprised 20 blood donors. One day after wounding, NO x , MDA, and ACE activity significantly increased. Subsequently, NO x and ACE activity decreased, whereas MDA increased. A significant negative correlation was found between NO x and MDA, and a significant positive correlation, between NO x and ACE activity. The correlations observed in the control group were undetectable in the patients one day after wounding but were restored on the third day. Thus, thoracic injury was accompanied by an increase in NO x and MDA, which determine the severity of oxidative stress. The positive correlation between NO x and ACE activity in the control and test groups reflects their concerted action in regulating the physiological functions and metabolism.  相似文献   
289.
The differences in expression of ERCC1 were estimated between tumor specimens embedded into paraffin blocks and surgical biopsy specimens of non-small cell lung cancer as well as breast and ovarian cancers. Concordance or differences not higher than 20% were observed in 73% of the cases. The number of the cases with more significant differences in ERCC1 expression was less than 17%. The results show that ERCC1 detection in surgical biopsy specimens by flow cytometry is the more preferable method due to reduced preanalytical phase of the analysis.  相似文献   
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