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71.
1% acetylcholine (5.5 10 M--acetylcholine chloride) applied directly to the cortex of conscious non-immobilized rabbits was established to produce neuroglial reaction in motor area. Following 30 min long application the number of astrocytes was significantly increased. Application lasting for 2 hrs resulted in a reverse effect. The above-mentioned changes were observed in surface and deep cortical layers. They were functional and could be attributed to the cell tinctorial properties. 相似文献
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MA Nesmeianova VI Krupianko AE Kalinin LIu Kadyrova 《Canadian Metallurgical Quarterly》1996,61(1):89-99
Natural and mutant alkaline phosphatases with amino acid substitutions in the processing site and N-terminal domain of the mature polypeptide chain Val for Ala(-1), Gln for Glu (+4) and simultaneously Gln for Glu (+4) and Ala for Arg (+1) have been isolated from the periplasm and cultural fluid of E. coli. It has been found that these substitutions have little effect on the dependence of the enzyme activity on pH, ionic strength and temperature but influence its isoenzymic spectrum and decrease (almost twofold) the maximal rate of the enzyme-catalyzed reaction. Extracellular enzymes display, in contrast with periplasmic ones, other catalytic properties (Vmax) and binding activity (Km). After translocation through the outer membrane all the enzymes display decreased Vmax and increased Km. These changes are especially well-pronounced in case of the mutant protein PhoA46 which contains an uncleaved signal peptide due to the impossibility of processing resulting from the substitution of Val for Ala(-1). The Vmax for this protein is decreased 20 times, while the Km is increased 4-fold. The protein also shows a higher (in comparison with other proteins) sensitivity towards proteolytic enzymes and is less resistant upon storage. The experimental data suggest that the changes in the N-end of alkaline phosphatase located at a long distance from its active center influence the enzyme function. 相似文献
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EL Vodovozova GP Gayenko VI Razinkov EY Korchagina NV Bovin JG Molotkovsky 《Canadian Metallurgical Quarterly》1998,44(3):543-553
The overexpression of lectins by malignant cells was applied for in vitro targeting of liposomes equipped with a saccharide vector and loaded in the lipid phase with a lipid derivative of anticancer agent sarcolysine. The lectin specificity of human leukemia HL-60 and human lung adenocarcinoma ACL cells was revealed by tests with fluorescein-labeled sugar probes. With the help of fluorescent lipid dye it was shown that active saccharide ligands increased the level of the vectored liposome binding to malignant cells by 50-80% as compared to liposomes without vector or with inactive one. The degree of liposome/cell membrane fusion was monitored fluorometrically and was shown to be complete and independent of the vectors. The targeted drug-loaded liposomes had the cytotoxic activity 2-4 times higher as compared to the vector-free ones. 相似文献
77.
The investigations of authors concerning infants and their families were generalized on the basis of the observations of infants and their parents with some psychological problems in families. The principles of psychotherapeutic work in above-mentioned groups were formulated. Besides the methods of the diagnosis of psychical deviations development in first year infants as well as peculiarities of alterations in mother-baby system and the main forms of psychic disturbances correction in infants were also described. 相似文献
78.
EI Sinauridze RI Volkova YV Krasotkina VI Sarbash FI Ataullakhanov 《Canadian Metallurgical Quarterly》1998,1425(3):607-616
We have tested whether action potential-evoked Ca2+ influx is required to initiate clathrin-mediated synaptic vesicle endocytosis in the lamprey reticulospinal synapse. Exo- and endocytosis were temporally separated by a procedure involving tonic action potential stimulation and subsequent removal of extracellular Ca2+ (Ca2+e). A low concentration of Ca2+ ([Ca2+]e of 11 microM) was found to be required for the induction of early stages of endocytosis. However, the entire endocytic process, from the formation of clathrin-coated membrane invaginations to the generation of synaptic vesicles, proceeded in the absence of action potential-mediated Ca2+ entry. Our results indicate that the membrane of synaptic vesicles newly incorporated in the plasma membrane is a sufficient trigger of clathrin-mediated synaptic vesicle endocytosis. 相似文献
79.
VI Turilova TD Smirnova MP Samo?lovich TR Sukhikh 《Canadian Metallurgical Quarterly》1998,40(6):536-548
The morphology and Ag-staining of nucleoli in human multiple myeloma cell lines RPMI 8226 and U 266, distinguished from each other in the differentiation degree, were quantitatively studied, and the production of immunoglobulins or their fragments by the line cells was evaluated throughout 7 days after cell seeding. The less differentiated cell line RPMI 8226 and the high differentiated cell line U 266 were revealed to differ in both the initial level of immunoglobulin production and dynamics of immunoglobulin accumulation in culture medium. The total number of Ag-stained nucleolar-organizer regions (AgNORs) per nucleus in cells RPMI 8226 was significantly higher than in cells U 266 in all times after seeding of the cells. In both cell lines changes in the quantity and shape of nucleoli and also in the total number of AgNORs per nucleus and pattern of AgNORs distribution within nucleoli correlated with the cell cycle phase. Relationships between morphofunctional changes in nucleoli and the differentiation degree and proliferative activity of the cells, and also between the number of Ag-positive nucleolar-organizing metaphase chromosomes and the functional activity of interphase AgNORs are discussed. 相似文献
80.
AIM: To study efficacy and tolerance of cardioselective beta-adrenoblocker lokren (betaxolol) in elderly patients with mild and moderate hypertension. MATERIALS AND METHODS: 25 elderly (mean age 70.2 +/- 1.43 years) hypertensive patients received lokren (a single dose of 10 mg daily for 3 months). The examination comprised routine tests, ECG, rheovasography of the ankle, REG of vertebral and carotid arteries, measurements of ejection fraction, total peripheral vascular resistance, myocardial mass, platelet aggregation, external respiration function, blood glucose, total cholesterol, triglycerides, beta-lipoprotein. RESULTS: The treatment produced a significant reduction in systolic (by 32.1% and 32.7% in position, respectively) and diastolic pressure (by 14.2 and 11.8%, respectively). Thickness of the posterior wall of the left ventricular myocardium decreased by 7.7%, ejection fraction by 2.9%, total peripheral vascular resistance went up by 11.5%. Spontaneous and induced platelet aggregation declined. There was an insignificant rise in the levels of cholesterol, beta-lipoproteins, triglycerides, glucose. REG and rheovasography data tended to a small rise. External respiration remained unchanged. The need in nitroglycerin reduced by 58%. CONCLUSION: Lokren (betaxolol) can be recommended as effective hypotensive monotherapy of mild and moderate blood hypertension in elderly patients. 相似文献