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A test system permitting the detection of influenza virus protein M at a concentration of 0.1-0.5 ng/ml in ELISA has been developed. The use of this system made it possible to detect influenza viruses A and B directly in crude virus-containing material and clinical samples obtained from influenza patients. During the outbreak of influenza in the spring of 1983 ELISA was successfully used for the rapid diagnosis of influenza, and some of its advantages in comparison with the conventional immunofluorescence test were thus demonstrated. To overcome difficulties arising from the low immunogenic potency of protein M, in the process of obtaining diagnostic sera and ascitic fluids the animals were immunized with the conjugate of protein M and polyelectrolite, which ensured considerable activation of humoral immune response.  相似文献   
3.
O A Smirnova  N V Stepanova 《Biofizika》1975,20(6):1095-1098
A mathematical model of autoimmunity is developed. This model is a system of two nonlinear differential equations, which describe the concentration dynamics of tissue cells and agressive lymphocytes. An analysis of the solutions shows that this model reproduces general behaviour of autoimmune diseases.  相似文献   
4.
The antigenic structure of the L-forms of salmonellae (S. typhimurium and S. typhi) in comparison with that of the initial bacterial cultures and revertant cultures was studied with the use of the immunoferritin method. The L-forms of salmonellae were found to retain an insignificant amount of O-antigen, as well as to have K-antigen on the surface of the cytoplasmic membrane, but in a lesser amount than the initial strains. In the cultures reverting from the L-forms of S. typhimurium and S. typhi the quantitative and qualitative characteristics of O- and K-antigens were completely restored.  相似文献   
5.
The content of cytochrome P450 and monooxygenase activity has been studied in the liver of Baikal fishes (Coregonus automnalis, Thymallus articus, Brachymystax lenok and Cottocomphorus greminsky). The administration of 3-methylcholanthrene increases considerably the level of metabolic activity of microsomal fraction and cytochrome P450 content in liver. The data of microsomal fractions of rats and fishes liver electrophoresis have shown that xenobiotic causes the synthesis of similar according to the molecular weight forms of cytochrome P450 in these animals. The induction of microsomal monooxygenase inhibits the lipid peroxidation of microsomal fraction.  相似文献   
6.
The survival rate of Mycobacterium lacticolum and the proportion between its R, S and M variants were studied in the course of 12 months under different conditions of storage (freeze-drying, under vaseline oil, in 0.85% NaCl solution and in distilled water). A high survival rate of the variants was found in cells freeze-dried in a protective medium containing 10% of sucrose +1% of gelatin as well as in a 0.85% solution of NaCl.The survival rate of te variants differed by 2--3 orders of magnitude in cells freeze-dried with sodium glutamate or suspended in distilled water. The proportion between the R, S and M variants in the population noticeable changed after storage under these conditions.  相似文献   
7.
A method of rapid freezing in supercooled Freon 22 (monochlorodifluoromethane) followed by cryoultramicrotomy is described and shown to yield ultrathin sections in which both the cellular ultrastructure and the distribution of diffusible ions across the cell membrane are preserved and intracellular compartmentalization of diffusabler ions can be quantitated. Quantitative electron probe analysis (Shuman, H., A.V. Somlyo, and A.P. Somlyo. 1976. Ultramicros. 1:317-339.) of freeze-dried ultrathin cryto sections was found to provide a valid measure of the composition of cells and cellular organelles and was used to determine the ionic composition of the in situ terminal cisternae of the sarcoplasmic reticulum (SR), the distribution of CI in skeletal muscle, and the effects of hypertonic solutions on the subcellular composition if striated muscle. There was no evidence of sequestered CI in the terminal cisternae of resting muscles, although calcium (66mmol/kg dry wt +/- 4.6 SE) was detected. The values of [C1](i) determined with small (50-100 nm) diameter probes over cytoplasm excluding organelles over nuclei or terminal cisternae were not significantly different. Mitochondria partially excluded C1, with a cytoplasmic/ mitochondrial Ci ratio of 2.4 +/- 0.88 SD. The elemental concentrations (mmol/kg dry wt +/- SD) of muscle fibers measured with 0.5-9-μm diameter electron probes in normal frog striated muscle were: P, 302 +/- 4.3; S, 189 +/- 2.9;C1, 24 +/- 1.1;K, 404 +/- 4.3, and Mg, 39 +/- 2.1. It is concluded that: (a) in normal muscle the "excess CI" measured with previous bulk chemical analyses and flux studies is not compartmentalized in the SR or in other cellular organelles, and (b) the cytoplasmic C1 in low [K](0) solutions exceeds that predicted by a passive electrochemical distribution. Hypertonic 2.2 X NaCl, 2.5 X sucrose, or 2.2 X Na isethionate produced: (a) swollen vacuoles, frequently paired, adjacent to the Z lines and containing significantly higher than cytoplasmic concentrations of Na and Cl or S (isethionate), but no detectable Ca, and (b) granules of Ca, Mg, and P = approximately (6 Ca + 1 Mg)/6P in the longitudinal SR. It is concluded that hypertonicity produces compartmentalized domains of extracellular solutes within the muscle fibers and translocates Ca into the longitudinal tubules.  相似文献   
8.
Toxicity of bleomycetin was studied on 3 animal species (rats, rabbits and dogs). The antibiotic was administered intramuscularly and intravenously in various doses for a prolonged period of time. The death of the rats, rabbits and dogs treated with repeated lethal doses of bleomycetin was due to its toxic effect on the kidneys and probably lungs. The level of urea in the blood of the animals before death increased up to 300--400 mg %. Histological examination of the kidneys revealed the picture of glomerulonephritis. The lungs were highly plethoric and showed areas of alveolar collapse and consolidation consisting mainly of the collapsed alveolar epithelium. The liver was not affected by bleomycetin according to both the results of some functional tests and histological examination. tthe blood sugar level after bleomycetin administration was not altered significantly. The changes in the peripheral blood were not pronounced. An increased P wave, decreased R wave and deep S wave were seen on the ECG. Such deviitions may be due not only to the changes in the myocardium but also to the lung affection. When bleomycetiin was used repeatedly in nonlethal doses (1 mg/kg for rats, 1--2 mg/kg for rabbits and 0.25--0.5 mg/kg for dogs), the above changes were less pronounced or not manifested at all. No inhibitory effect on hemopoiesis is an important positive characteristics of bleomycetin, so that it compares very favourably with most other antitumor drugs.  相似文献   
9.
Contents of histamine, 5-hydroxytryptamine, functional state of heparinic proteoglycan have been studied in the rat peritoneal mast cells during various seasons of the year (January-February, May-June, July). In winter the mast cells have a high content of histamine and 5-hydroxytryptamine, heparinic proteoglycan of their granules is stained with both alcian blue and safranin. In summer (July) content of histamine in the mast cells is sharply decreased in comparison with that of 5-hydroxytryptamine and in May-June the content of both amines is decreased nearly to background values. Both during spring and summer periods heparinic proteoglycan of the mast cell granules is stained only with alcian blue and does not take safranin. A suggestion is made on independence of the seasonal changes of annual rhythmical pattern of histamine and 5-hydroxytryptamine contents in the mast cells. A conclusion is made concerning possible participation of the mast cell system of organs and tissues in the seasonal changes of biogenic amine levels in them.  相似文献   
10.
The methods for chimeric chromosomes' destabilization and the standard tetrad analysis have been used for mapping of the yeast genes XRS2 and HIM1. The genes are localized in the right arm of chromosome IV in the following order: XRS2-31cM-ADE8-28.5cM-HIM1.  相似文献   
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